if - "use" a Perl module if a condition holds (also can "no" a module) The "if" module is used to conditionally load or unload another module. The construct will load MODULE only if CONDITION evaluates to true. The above statement has no effect unless "CONDITION" is true. If the CONDITION does evaluate to true, then the above line has the same effect as: The use of "=>" above provides necessary quoting of "MODULE". If you don't use the fat comma (eg you % select — synchronous I/O multiplexing #include int select(int nfds, fd_set *restrict readfds, fd_set *restrict writefds, fd_set *restrict errorfds, struct timeval *restrict timeout); Refer to pselect(). % time - time a simple command or give resource usage time [options] command [arguments...] The time command runs the specified program command with the given arguments. When command finishes, time writes a message to standard error giving timing statistics about this program run. These statis‐ tics consist of (i) the elapsed real time between invocation and termination, (ii) the user CPU time (the pathname (something like /usr/bin/time). % alias — define or display aliases alias [alias-name[=string]...] The alias utility shall create or redefine alias definitions or write the values of existing alias defi‐ nitions to standard output. An alias definition provides a string value that shall replace a command name An alias definition shall affect the current shell execution environment and the execution environments % bg — run jobs in the background bg [job_id...] If job control is enabled (see the description of set −m), the bg utility shall resume suspended jobs ground jobs. If the job specified by job_id is already a running background job, the bg utility shall have no effect and shall exit successfully. Using bg to place a job into the background shall cause its process ID to become ``known in the current % bind — bind a name to a socket #include int bind(int socket, const struct sockaddr *address, socklen_t address_len); The bind() function shall assign a local socket address address to a socket identified by descriptor socket that has no local socket address assigned. Sockets created with the socket() function are ini‐ tially unnamed; they are identified only by their address family. % break — exit from for, while, or until loop break [n] The break utility shall exit from the smallest enclosing for, while, or until loop, if any; or from the nth enclosing loop if n is specified. The value of n is an unsigned decimal integer greater than or equal outermost enclosing loop shall be exited. Execution shall continue with the command immediately following the loop. % cd — change the working directory cd [−L|−P] [directory] cd − The cd utility shall change the working directory of the current shell execution environment (see Section the symbol curpath represents an intermediate value used to simplify the description of the algorithm used by cd. There is no requirement that curpath be made visible to the application.) % command — execute a simple command command [−p] command_name [argument...] command [−p][−v|−V] command_name The command utility shall cause the shell to treat the arguments as a simple command, suppressing the If the command_name is the same as the name of one of the special built-in utilities, the special proper‐ % continue — continue for, while, or until loop continue [n] The continue utility shall return to the top of the smallest enclosing for, while, or until loop, or to while or until loop or performing the next assignment of a for loop, and re-executing the loop if appro‐ priate. % echo - display a line of text echo [SHORT-OPTION]... [STRING]... echo LONG-OPTION Echo the STRING(s) to standard output. -n do not output the trailing newline -e enable interpretation of backslash escapes -E disable interpretation of backslash escapes (default) --help display this help and exit % eval — construct command by concatenating arguments eval [argument...] The eval utility shall construct a command by concatenating arguments together, separating each with a character. The constructed command shall be read and executed by the shell. None. % exec — execute commands and open, close, or copy file descriptors exec [command [argument...]] The exec utility shall open, close, and/or copy file descriptors as specified by any redirections as part of the command. are opened with associated redirection statements, it is unspecified whether those file descriptors remain open when the shell invokes another utility. Scripts concerned that child shells could misuse % exit — cause the shell to exit exit [n] The exit utility shall cause the shell to exit with the exit status specified by the unsigned decimal undefined. A trap on EXIT shall be executed before the shell terminates, except when the exit utility is invoked in % export — set the export attribute for variables export name[=word]... export −p The shell shall give the export attribute to the variables corresponding to the specified names, which shall cause them to be in the environment of subsequently executed commands. If the name of a variable is followed by =word, then the value of that variable shall be set to word. % false - do nothing, unsuccessfully false [ignored command line arguments] false OPTION Exit with a status code indicating failure. --help display this help and exit --version output version information and exit Please refer to your shell's documentation for details about the options it supports. % fc — process the command history list fc [−r] [−e editor] [first [last]] fc −l [−nr] [first [last]] fc −s [old=new] [first] The fc utility shall list, or shall edit and re-execute, commands previously entered to an interactive sh. % fg — run jobs in the foreground fg [job_id] If job control is enabled (see the description of set −m), the fg utility shall move a background job Using fg to place a job into the foreground shall remove its process ID from the list of those ``known in % getopts — parse utility options getopts optstring name [arg...] The getopts utility shall retrieve options and option-arguments from a list of parameters. It shall sup‐ Each time it is invoked, the getopts utility shall place the value of the next option in the shell vari‐ able specified by the name operand and the index of the next argument to be processed in the shell vari‐ % hash — remember or report utility locations hash [utility...] hash −r The hash utility shall affect the way the current shell environment remembers the locations of utilities fied, it shall add utility locations to its list of remembered locations or it shall purge the contents of the list. When no arguments are specified, it shall report on the contents of the list. % history - GNU History Library Many programs read input from the user a line at a time. The GNU History library is able to keep track of those lines, associate arbitrary data with each line, and utilize information from previous lines in composing new ones. HISTORY EXPANSION The history library supports a history expansion feature that is identical to the history expansion in History expansions introduce words from the history list into the input stream, making it easy to repeat commands, insert the arguments to a previous command into the current input line, or fix errors in previ‐ ous commands quickly. % jobs — display status of jobs in the current session jobs [−l|−p] [job_id...] The jobs utility shall display the status of jobs that were started in the current shell environment; see When jobs reports the termination status of a job, the shell shall remove its process ID from the list of % kill - terminate a process kill [-signal|-s signal|-p] [-q value] [-a] [--] pid|name... kill -l [number] | -L The command kill sends the specified signal to the specified processes or process groups. If no signal caught. Most modern shells have a builtin kill function, with a usage rather similar to that of the command described here. The --all, --pid, and --queue options, and the possibility to specify processes by com‐ mand name, are local extensions. If signal is 0, then no actual signal is sent, but error checking is still performed. % login, logout - write utmp and wtmp entries #include void login(const struct utmp *ut); int logout(const char *ut_line); Link with -lutil. The utmp file records who is currently using the system. The wtmp file records all logins and logouts. The function login() takes the supplied struct utmp, ut, and writes it to both the utmp and the wtmp file. % printf - format and print data printf FORMAT [ARGUMENT]... printf OPTION Print ARGUMENT(s) according to FORMAT, or execute according to OPTION: --help display this help and exit --version output version information and exit FORMAT controls the output as in C printf. Interpreted sequences are: \" double quote % pwd - print name of current/working directory pwd [OPTION]... Print the full filename of the current working directory. -L, --logical use PWD from environment, even if it contains symlinks -P, --physical avoid all symlinks --help display this help and exit --version % read — read a line from standard input read [−r] var... The read utility shall read a single line from standard input. By default, unless the −r option is specified, shall act as an escape character. An unescaped shall preserve the literal value of the following character, with the exception of a . If a follows the , the read utility shall interpret this as line continua‐ tion. The and shall be removed before splitting the input into fields. All other % readonly — set the readonly attribute for variables readonly name[=word]... readonly −p The variables whose names are specified shall be given the readonly attribute. The values of variables with the readonly attribute cannot be changed by subsequent assignment, nor can those variables be unset by the unset utility. If the name of a variable is followed by =word, then the value of that variable shall be set to word. % return — return from a function or dot script return [n] The return utility shall cause the shell to stop executing the current function or dot script. If the shell is not currently executing a function or dot script, the results are unspecified. None. % set — set or unset options and positional parameters set [−abCefhmnuvx] [−o option] [argument...] set [+abCefhmnuvx] [+o option] [argument...] set −− [argument...] set −o set +o % shift — shift positional parameters shift [n] the new number of positional parameters. The value n shall be an unsigned decimal integer less than or equal to the value of the special parameter % test - check file types and compare values test EXPRESSION test [ EXPRESSION ] [ ] [ OPTION Exit with the status determined by EXPRESSION. --help display this help and exit --version output version information and exit % times — write process times times The times utility shall write the accumulated user and system times for the shell and for all of its child processes, in the following POSIX locale format: "%dm%fs %dm%fs\n%dm%fs %dm%fs\n", , , , , , % trap — trap signals trap n [condition...] trap [action condition...] If the first operand is an unsigned decimal integer, the shell shall treat all operands as conditions, and shall reset each condition to the default value. Otherwise, if there are operands, the first is treated as an action and the remaining as conditions. If action is '−', the shell shall reset each condition to the default value. If action is null (""), the % true - do nothing, successfully true [ignored command line arguments] true OPTION Exit with a status code indicating success. --help display this help and exit --version output version information and exit Please refer to your shell's documentation for details about the options it supports. % type — write a description of command type type name... The type utility shall indicate how each argument would be interpreted if used as a command name. None. OPERANDS % ulimit — set or report file size limit ulimit [−f] [blocks] The ulimit utility shall set or report the file-size writing limit imposed on files written by the shell increase the limit. % umask — get or set the file mode creation mask umask [−S] [mask] The umask utility shall set the file mode creation mask of the current shell execution environment (see affect the initial value of the file permission bits of subsequently created files. If umask is called in a subshell or separate utility execution environment, such as one of the following: % unalias — remove alias definitions unalias alias-name... unalias −a Substitution. The aliases shall be removed from the current shell execution environment; see Section % unset — unset values and attributes of variables and functions unset [−fv] name... Each variable or function specified by name shall be unset. If −v is specified, name refers to a variable name and the shell shall unset it and remove it from the environment. Read-only variables cannot be unset. If −f is specified, name refers to a function and the shell shall unset the function definition. % wait — await process completion wait [pid...] last command in each element of the asynchronous list shall become known in the current shell execution If the wait utility is invoked with no operands, it shall wait until all process IDs known to the invok‐ ing shell have terminated and exit with a zero exit status. % timedatectl - Control the system time and date The following options are understood: --no-ask-password Do not query the user for authentication for privileged operations. --adjust-system-clock % iptables-save — dump iptables rules to stdout ip6tables-save — dump iptables rules to stdout iptables-save [-M modprobe] [-c] [-t table] ip6tables-save [-M modprobe] [-c] [-t table] iptables-save and ip6tables-save are used to dump the contents of IP or IPv6 Table in easily parseable format to STDOUT. Use I/O-redirection provided by your shell to write to a file. -M, --modprobe modprobe_program Specify the path to the modprobe program. By default, iptables-save will inspect /proc/sys/ker‐ nel/modprobe to determine the executable's path. % c_rehash - Create symbolic links to files named by the hash values c_rehash [-old] [-h] [-n] [-v] [ directory...] c_rehash scans directories and calculates a hash value of each ".pem", ".crt", ".cer", or ".crl" file in the specified directory list and creates symbolic links for each file, where the name of the link is the as many programs that use OpenSSL require directories to be set up like this in order to find certificates. If any directories are named on the command line, then those are processed in turn. If not, then the SSL_CERT_DIR environment variable is consulted; this shold be a colon-separated list of directories, like the Unix PATH variable. If that is not set then the default directory (installation-specific but often /usr/local/ssl/certs) is processed. % gdbm_load - re-create a GDBM database from a dump file. [--block-size=NUM] [--cache-size=NUM] [--mmap=NUM] [--mode=MODE] [--no-meta] [--replace] gdbm_load [-Vh] [--help] [--usage] [--version] Create a gdbm database file DB_FILE from the dump file FILE. If the FILE argument is not supplied, out‐ put the created database to the standard error. If the input file is in ASCII dump format, the mode and ownership of the created database are restored % yes - output a string repeatedly until killed yes [STRING]... yes OPTION Repeatedly output a line with all specified STRING(s), or 'y'. --help display this help and exit --version output version information and exit Written by David MacKenzie. % named-checkconf - named configuration file syntax checking tool named-checkconf [-h] [-v] [-j] [-t directory] {filename} [-p] [-x] [-z] named-checkconf checks the syntax, but not the semantics, of a named configuration file. The file is parsed and checked for syntax errors, along with all files included by it. If no file is specified, /etc/named.conf is read by default. run, even if named-checkconf was successful. named-checkconf can be run on these files explicitly, however. -h % grotty - groff driver for typewriter-like devices grotty [ -bBcdfhioruUv ] [ -Fdir ] [ files... ] It is possible to have whitespace between the -F option and its parameter. grotty translates the output of GNU troff into a form suitable for typewriter-like devices. Normally the standard input. A filename of - also causes grotty to read the standard input. Output is written to the standard output. foreground colors; additionally, bold and italic attributes can be used at the same time (by using the BI % systemd-machine-id-setup - Initialize the machine ID in /etc/machine-id systemd-machine-id-setup information about this file. If the tool is invoked without the --commit switch, /etc/machine-id is initialized with a valid, new machined ID if it is missing or empty. The new machine ID will be acquired in the following fashion: used to initialize the machine ID in /etc/machine-id. % bridge - show / manipulate bridge addresses and devices OBJECT := { link | fdb | mdb | vlan | monitor } bridge link set dev DEV [ cost COST ] [ priority PRIO ] [ state STATE] [ guard { on | off } ] [ hairpin { on | off } ] [ fastleave { on | off } ] [ root_block { on | off } ] [ learning { on | off } ] [ learning_sync { on | off } ] [ flood { on | off } ] [ hwmode { vepa | veb } ] [ self ] [ master ] bridge link [ show ] [ dev DEV ] bridge fdb { add | append | del | replace } LLADDR dev DEV { local | static | dynamic } [ self ] [ master ] [ router ] [ use ] [ dst IPADDR ] [ vni VNI ] [ port PORT ] [ via DEVICE ] % grub-mkrelpath - make a system path relative to its root grub-mkrelpath [OPTION...] PATH Transform a system filename into GRUB one. -?, --help give this help list --usage give a short usage message -V, --version print program version % vgrename — rename a volume group will refuse to run or give warning messages. a Volume Group with the same name as the Volume Group containing your root filesystem the machine might not even boot correctly. However, the two Volume Groups should have different UUIDs (unless the disk was cloned) so you can rename one of the conflicting Volume Groups with vgrename. % rename - rename files rename [options] expression replacement file... rename will rename the specified files by replacing the first occurrence of expression in their name by replacement. -s, --symlink Do not rename a symlink but its target. -v, --verbose Show which files where renamed, if any. -V, --version % grub-install - install GRUB to a device grub-install [OPTION...] [OPTION] [INSTALL_DEVICE] Install GRUB on your drive. --compress=no|xz|gz|lzo compress GRUB files [optional] -d, --directory=DIR use images and modules under DIR [default=/usr/lib/grub/] --fonts=FONTS install FONTS [default=unicode] % pvck — check physical volume metadata calVolume [PhysicalVolume...] pvck checks physical volume LVM metadata for consistency. --labelsector sector parameter allows you to specify a different starting sector for the scan and is useful for recov‐ ery situations. For example, suppose the partition table is corrupted or lost on /dev/sda, but % xfs_copy - copy the contents of an XFS filesystem xfs_copy -V argument must be the pathname of the device or file containing the XFS filesystem. The remaining argu‐ ments specify one or more target devices or file names. If the pathnames specify devices, a copy of the source XFS filesystem is created on each device. The target can also be the name of a regular file, in xfs_copy creates the file. The length of the resulting file is equal to the size of the source filesys‐ tem. However, if the file is created on an XFS filesystem, the file consumes roughly the amount of space actually used in the source filesystem by the filesystem and the XFS log. The space saving is because xfs_copy seeks over free blocks instead of copying them and the XFS filesystem supports sparse files efficiently. % pacman - package manager utility pacman [options] [targets] Pacman is a package management utility that tracks installed packages on a Linux system. It features dependency support, package groups, install and uninstall scripts, and the ability to sync your local machine with a remote repository to automatically upgrade packages. Pacman packages are a zipped tar format. Invoking pacman involves specifying an operation with any potential options and targets to operate on. A target is usually a package name, file name, URL, or a search string. Targets can be provided as command line arguments. Additionally, if stdin is not from a terminal and a single hyphen (-) is passed as an % ip - show / manipulate routing, devices, policy routing and tunnels ip [ -force ] -batch filename OBJECT := { link | address | addrlabel | route | rule | neigh | ntable | tunnel | tuntap | maddress | flush-attempts } | -o[neline] | -rc[vbuf] [size] | -t[imestamp] | -ts[hort] | -n[etns] name | -a[ll] | -c[olor] } -V, -Version % mk_cmds - error table compiler mk_cmds file Mk_cmds converts a table listing command names and associated help messages into a C source file suitable The source file name must end with a suffix of ``.ct''; the file consists of a declaration supplying the name of the command table: command_table name followed by entries of the form: [ request | unimplemented ] name, " string "[, abbrev]...; % uniq - report or omit repeated lines uniq [OPTION]... [INPUT [OUTPUT]] Filter adjacent matching lines from INPUT (or standard input), writing to OUTPUT (or standard output). With no options, matching lines are merged to the first occurrence. Mandatory arguments to long options are mandatory for short options too. -c, --count prefix lines by the number of occurrences -d, --repeated only print duplicate lines, one for each group % ldattach - attach a line discipline to a serial line The ldattach daemon opens the specified device file (which should refer to a serial device) and attaches the line discipline ldisc to it for processing of the sent and/or received data. It then goes into the background keeping the device open so that the line discipline stays loaded. With no arguments, ldattach prints usage information. LINE DISCIPLINES % gawk - pattern scanning and processing language gawk [ POSIX or GNU style options ] -f program-file [ -- ] file ... gawk [ POSIX or GNU style options ] [ -- ] program-text file ... Gawk is the GNU Project's implementation of the AWK programming language. It conforms to the definition AWK Programming Language, by Aho, Kernighan, and Weinberger. Gawk provides the additional features found in the current version of Brian Kernighan's awk and a number of GNU-specific extensions. The command line consists of options to gawk itself, the AWK program text (if not supplied via the -f or --file options), and values to be made available in the ARGC and ARGV pre-defined AWK variables. When gawk is invoked with the --profile option, it starts gathering profiling statistics from the execu‐ tion of the program. Gawk runs more slowly in this mode, and automatically produces an execution profile % lookbib - search bibliographic databases lookbib [ -v ] [ -istring ] [ -tn ] filename... lookbib prints a prompt on the standard error (unless the standard input is not a terminal), reads from the standard input a line containing a set of keywords, searches the bibliographic databases filename... for references containing those keywords, prints any references found on the standard output, and repeats this process until the end of input. For each database filename to be searched, if an index filename.i It is possible to have whitespace between a command line option and its parameter. -v Print the version number. % size - list section sizes and total size. size [-A|-B|--format=compatibility] [--help] [-d|-o|-x|--radix=number] [--common] [-t|--totals] [--target=bfdname] [-V|--version] [objfile...] The GNU size utility lists the section sizes---and the total size---for each of the object or archive files objfile in its argument list. By default, one line of output is generated for each object file or each module in an archive. objfile... are the object files to be examined. If none are specified, the file "a.out" will be used. % join - join lines of two files on a common field For each pair of input lines with identical join fields, write a line to standard output. The default join field is the first, delimited by blanks. -a FILENUM -e EMPTY replace missing input fields with EMPTY % idle - make process 0 idle #include int idle(void); idle() is an internal system call used during bootstrap. It marks the process's pages as swappable, low‐ ers its priority, and enters the main scheduling loop. idle() never returns. EPERM. RETURN VALUE % refer - preprocess bibliographic references for groff refer [ -benvCPRS ] [ -an ] [ -cfields ] [ -fn ] [ -ifields ] [ -kfield ] [ -lm,n ] [ -pfilename ] [ -sfields ] [ -tn ] [ -Bfield.macro ] [ filename... ] refer copies the contents of filename... to the standard output, except that lines between .[ and .] are are to be processed. Each citation specifies a reference. The citation can specify a reference that is contained in a biblio‐ graphic database by giving a set of keywords that only that reference contains. Alternatively it can specify a reference by supplying a database record in the citation. A combination of these alternatives is also possible. % xzmore, lzmore - view xz or lzma compressed (text) files xzmore [file...] lzmore [file...] time on a soft-copy terminal. To use a pager other than the default more, set environment variable PAGER to the name of the desired program. The name lzmore is provided for backward compatibility with LZMA Utils. e or q When the prompt --More--(Next file: file) is printed, this command causes xzmore to exit. s When the prompt --More--(Next file: file) is printed, this command causes xzmore to skip the next file and continue. % sserver [ -p port ] [ -S keytab ] [ server_port ] sserver, it performs a Kerberos authentication, and then sserver returns to sclient the Kerberos princi‐ pal which was used for the Kerberos authentication. It makes a good test that Kerberos has been success‐ fully installed on a machine. The service name used by sserver and sclient is sample. Hence, sserver will require that there be a The -S option allows for a different keytab than the default. % wc - print newline, word, and byte counts for each file wc [OPTION]... [FILE]... wc [OPTION]... --files0-from=F Print newline, word, and byte counts for each FILE, and a total line if more than one FILE is specified. A word is a non-zero-length sequence of characters delimited by white space. With no FILE, or when FILE is -, read standard input. word, character, byte, maximum line length. -c, --bytes print the byte counts % calc_tickadj - Calculates optimal value for tick given ntp drift file. calc_tickadj [-flags] [-flag [value]] [--option-name[[=| ]value]] All arguments must be options. The calc_tickadj script uses provided ntp drift file to generate optimal tick value. Generally, ntpd can do better job if the drift value is the smallest possible number. The example output of $ ./calc_tickadj 9999 usec; 9999779 nsec $ cat /etc/ntp/drift % pcap-config - write libpcap compiler and linker flags to standard output pcap-config [ --static ] [ --cflags | --libs | --additional-libs ] When run with the --cflags option, pcap-config writes to the standard output the -I compiler flags required to include libpcap's header files. When run with the --libs option, pcap-config writes to the standard output the -L and -l linker flags required to link with libpcap, including -l flags for libraries required by libpcap. When run with the --additional-libs option, pcap-config writes to the standard output the -L and -l flags for libraries required by libpcap, but not the -lpcap flag to link with libpcap itself. By default, it writes flags appropriate for compiling with a dynamically-linked version of libpcap; the --static flag causes it to write flags appropriate for compiling with a statically-linked version of libpcap. % xfs_logprint - print the log of an XFS filesystem xfs_logprint [ options ] device the partition or logical volume containing the filesystem. The device can be a regular file if the -f option is used. The contents of the filesystem remain undisturbed. There are two major modes of opera‐ tion in xfs_logprint. One mode is better for filesystem operation debugging. It is called the transactional view and is enabled through the -t option. The transactional view prints only the portion of the log that pertains to tries to display each transaction without regard to how they are split across log records. The second mode starts printing out information from the beginning of the log. Some error blocks might % kswitch - switch primary ticket cache kswitch {-c cachename|-p principal} kswitch makes the specified credential cache the primary cache for the collection, if a cache collection is available. -c cachename Directly specifies the credential cache to be made primary. -p principal Causes the cache collection to be searched for a cache containing credentials for principal. If one is found, that collection is made primary. % hexdump - display file contents in hexadecimal, decimal, octal, or ascii hexdump [options] file... The hexdump utility is a filter which displays the specified files, or standard input if no files are specified, in a user-specified format. -b, --one-byte-octal One-byte octal display. Display the input offset in hexadecimal, followed by sixteen space-sepa‐ rated, three-column, zero-filled bytes of input data, in octal, per line. % btrfs - a toolbox to manage btrfs filesystems btrfs [] The btrfs utility is a toolbox for managing btrfs filesystems. There are command groups to work with There are also standalone tools for some tasks like btrfs-convert or btrfstune that were separate historically and/or haven’t been merged to the main utility. See section STANDALONE TOOLS for more details. Any command name can be shortened as far as it stays unambiguous, however it is recommended to use full % xzdec, lzmadec - Small .xz and .lzma decompressors xzdec [option...] [file...] lzmadec [option...] [file...] xzdec is a liblzma-based decompression-only tool for .xz (and only .xz) files. xzdec is intended to work xz --decompress --stdout (and possibly a few other commonly used options) to decompress .xz files. lzmadec is identical to xzdec except that lzmadec supports .lzma files instead of .xz files. To reduce the size of the executable, xzdec doesn't support multithreading or localization, and doesn't read options from XZ_DEFAULTS and XZ_OPT environment variables. xzdec doesn't support displaying inter‐ process instead of displaying progress information. % mii-tool - view, manipulate media-independent interface status mii-tool [-v, --verbose] [-V, --version] [-R, --reset] [-r, --restart] [-w, --watch] [-l, --log] [-A, --advertise=media,...] [-F, --force=media] [-p, --phy=addr] interface ... Most fast ethernet adapters use an MII to autonegotiate link speed and duplex setting. Most intelligent network devices use an autonegotiation protocol to communicate what media technologies they support, and then select the fastest mutually supported media technology. The -A or --advertise options can be used to tell the MII to only advertise a subset of its capabilities. Some passive devices, such as single-speed hubs, are unable to autonegotiate. To handle such devices, the MII proto‐ -F or --force options can be used to force the MII to operate in one mode, instead of autonegotiating. The -A and -F options are mutually exclusive. % lsblk - list block devices lsblk [options] [device...] lsblk lists information about all available or the specified block devices. The lsblk command reads the sysfs filesystem and udev db to gather information. The command prints all block devices (except RAM disks) in a tree-like format by default. Use lsblk --help to get a list of all available columns. The default output, as well as the default output from options like --fs and --topology, is subject to change. So whenever possible, you should avoid using default outputs in your scripts. Always explicitly define expected columns by using --output columns-list in environments where a stable output is required. % watch - execute a program periodically, showing output fullscreen watch [options] command run until interrupted. -d, --differences [permanent] Highlight the differences between successive updates. Option will read optional argument that changes highlight to be permanent, allowing to see what has changed at least once since first iteration. -n, --interval seconds % slattach - attach a network interface to a serial line slattach [-dehlLmnqv] [-c command] [-p proto] [-s speed] [tty] Slattach is a tiny little program that can be used to put a normal terminal ("serial") line into one of several "network" modes, thus allowing you to use it for point-to-point links to other computers. tty Path to a serial device like /dev/ttyS*, /dev/cua* or /dev/ptmx to spawn a new pseudo tty. [-c command] tions when a link goes down. [-d] Enable debugging output. Useful when determining why a given setup doesn't work. % systemd-notify - Notify service manager about start-up completion and other daemon status changes used to send arbitrary information, encoded in an environment-block-like list of strings. Most importantly, it can be used for start-up completion notification. set for the service unit this command is called from. % xzgrep - search compressed files for a regular expression xzgrep [grep_options] [-e] pattern file... xzegrep ... xzfgrep ... lzgrep ... lzegrep ... lzfgrep ... % xfs_io - debug the I/O path of an XFS filesystem xfs_io [ -adfmrRstxT ] [ -c cmd ] ... [ -p prog ] file xfs_io -V than the raw XFS volume itself. These code paths include not only the obvious read/write/mmap interfaces for manipulating files, but also cover all of the XFS extensions (such as space preallocation, additional inode flags, etc). gram exits. % pkttyagent - Textual authentication helper pkttyagent [--version] [--help] pkttyagent [--process { pid | pid,pid-start-time } | --system-bus-name busname] [--notify-fd fd] [--fallback] pkttyagent is used to start a textual authentication agent for the subject specified by either --process or --system-bus-name. If neither of these options are given, the parent process is used. To get notified when the authentication agent has been registered either listen to the Changed D-Bus signal or use --notify-fd to pass the number of a file descriptor that has been passed to the program. If --fallback is used, the textual authentication agent will not replace an existing authentication % more - file perusal filter for crt viewing more [options] file... Options are also taken from the environment variable MORE (make sure to precede them with a dash (-)) but command-line options will override those. -d Prompt with "[Press space to continue, 'q' to quit.]", and display "[Press 'h' for instructions.]" instead of ringing the bell when an illegal key is pressed. -l Do not pause after any line containing a ^L (form feed). % head - output the first part of files head [OPTION]... [FILE]... header giving the file name. With no FILE, or when FILE is -, read standard input. Mandatory arguments to long options are mandatory for short options too. -c, --bytes=[-]NUM print the first NUM bytes of each file; with the leading '-', print all but the last NUM bytes of each file % expr - evaluate expressions expr EXPRESSION expr OPTION --help display this help and exit --version output version information and exit Print the value of EXPRESSION to standard output. A blank line below separates increasing precedence % ipset — administration tool for IP sets | version | - } -file filename } % objdump - display information from object files. objdump [-a|--archive-headers] [-b bfdname|--target=bfdname] [-C|--demangle[=style] ] [-d|--disassemble] [-D|--disassemble-all] [-z|--disassemble-zeroes] [-EB|-EL|--endian={big | little }] [-f|--file-headers] [-F|--file-offsets] [--file-start-context] [-g|--debugging] [-e|--debugging-tags] [-h|--section-headers|--headers] [-i|--info] % gresource - GResource tool gresource [--section SECTION] list FILE [PATH] gresource [--section SECTION] details FILE [PATH] gresource [--section SECTION] extract FILE PATH gresource sections FILE gresource offers a simple commandline interface to GResource. It lets you list and extract resources that have been compiled into a resource file or included in an elf file (a binary or a shared library). % lvmdiskscan scans all SCSI, (E)IDE disks, multiple devices and a bunch of other block devices in the sys‐ tem looking for LVM physical volumes. The size reported is the real device size. Define a filter in -l, --lvmpartition Only reports Physical Volumes. % numfmt - Convert numbers from/to human-readable strings numfmt [OPTION]... [NUMBER]... Reformat NUMBER(s), or the numbers from standard input if none are specified. Mandatory arguments to long options are mandatory for short options too. --debug print warnings about invalid input -d, --delimiter=X use X instead of whitespace for field delimiter --field=FIELDS % logsave - save the output of a command in a logfile logsave [ -asv ] logfile cmd_prog [ ... ] The logsave program will execute cmd_prog with the specified argument(s), and save a copy of its output to logfile. If the containing directory for logfile does not exist, logsave will accumulate the output in memory until it can be written out. A copy of the output will also be written to standard output. If cmd_prog is a single hyphen ('-'), then instead of executing a program, logsave will take its input from standard input and save it in logfile logsave is useful for saving the output of initial boot scripts until the /var partition is mounted, so the output can be written to /var/log. % certtool - GnuTLS certificate tool certtool [-flags] [-flag [value]] [--option-name[[=| ]value]] All arguments must be options. or non interactively by specifying the template command line option. provide it using the environment variables GNUTLS_PIN and GNUTLS_SO_PIN. -d number, --debug=number % systemd-socket-activate - Test socket activation of daemons connection. The daemon to launch and its options should be specified after options intended for systemd-socket-activate. If the --inetd option is given, the socket file descriptor will be used as the standard input and output of the launched process. Otherwise, standard input and output will be inherited, and sockets will be systemd-socket-activate will be passed through to the daemon, in the original positions. Other sockets % losetup - set up and control loop devices Get info: losetup loopdev losetup -l [-a] losetup -j file [-o offset] Detach a loop device: losetup -d loopdev... Detach all associated loop devices: % passwd - change user password passwd [options] [LOGIN] the account or associated password validity period. Password Changes and compared against the stored password. The user has only one chance to enter the correct password. The After the password has been entered, password aging information is checked to see if the user is permitted to change the password at this time. If not, passwd refuses to change the password and exits. % unicode_stop - revert keyboard and console from unicode mode unicode_stop The unicode_stop command will more-or-less undo the effect of unicode_start. It puts the keyboard in % sudo, sudoedit — execute a command as another user sudo -h | -K | -k | -V sudo -v [-AknS] [-a type] [-g group] [-h host] [-p prompt] [-u user] sudo -l [-AknS] [-a type] [-g group] [-h host] [-p prompt] [-U user] [-u user] [command] sudo [-AbEHnPS] [-a type] [-C num] [-c class] [-g group] [-h host] [-p prompt] [-r role] [-t type] [-u user] [VAR=value] [-i | -s] [command] sudoedit [-AknS] [-a type] [-C num] [-c class] [-g group] [-h host] [-p prompt] [-u user] file ... sudo allows a permitted user to execute a command as the superuser or another user, as specified by the security policy. The invoking user's real (not effective) user ID is used to determine the user name with which to query the security policy. sudo supports a plugin architecture for security policies and input/output logging. Third parties can develop and distribute their own policy and I/O logging plugins to work seamlessly with the sudo front end. % groff - front-end for the groff document formatting system groff [-abcegijklpstzCEGNRSUVXZ] [-d cs] [-D arg] [-f fam] [-F dir] [-I dir] [-K arg] [-L arg] [-m name] [-M dir] [-n num] [-o list] [-P arg] [-r cn] [-T dev] [-w name] [-W name] [file ...] groff -h | --help groff -v | --version [option ...] The groff program and macro suite is the implementation of a roff(7) system within the free software col‐ lection GNU ⟨http://www.gnu.org⟩. The groff system has all features of the classical roff, but adds many extensions. % tzselect - select a timezone tzselect The tzselect program asks the user for information about the current location, and outputs the resulting timezone description to standard output. The output is suitable as a value for the TZ environment vari‐ able. All interaction with the user is done via standard input and standard error. The exit status is zero if a timezone was successfully obtained from the user, nonzero otherwise. ENVIRONMENT % modprobe - Add and remove modules from the Linux Kernel modprobe [-v] [-V] [-C config-file] [-n] [-i] [-q] [-b] [modulename] [module parameters...] modprobe [-r] [-v] [-n] [-i] [modulename...] modprobe [-c] modprobe [--dump-modversions] [filename] modprobe intelligently adds or removes a module from the Linux kernel: note that for convenience, there is no difference between _ and - in module names (automatic underscore conversion is performed). modprobe looks in the module directory /lib/modules/`uname -r` for all the modules and other files, modprobe will also use module options specified on the kernel command line in the form of % systemd-hwdb - hardware database management tool systemd-hwdb [options] update systemd-hwdb [options] query modalias systemd-hwdb expects a command and command specific arguments. It manages the binary hardware database. -h, --help Print help text. --usr Generate in /usr/lib/udev instead of /etc/udev. % named - Internet domain name server [-M option] [-m flag] [-n #cpus] [-p port] [-s] [-S #max-socks] [-t directory] [-U #listeners] [-u user] [-v] [-V] [-X lock-file] [-x cache-file] When invoked without arguments, named will read the default configuration file /etc/named.conf, read any initial data, and listen for queries. % systemctl - Control the systemd system and service manager manages. The following options are understood: -t, --type= The argument should be a comma-separated list of unit types such as service and socket. If one of the arguments is a unit type, when listing units, limit display to certain unit types. % geouplookup6 - look up country using IP Address or hostname geouplookup6 [-d directory] [-f filename] [-v] geouplookup6 uses the GeoIP library and database to find the Country that an IP address or hostname orig‐ inates from. You must install a database suitable for geoiplookup6. IE: GeoIPv6.dat For example: geoiplookup6 ipv6.google.com % external-journal ] [ -E extended_options ] [ -z undo_file ] device use a journal, if the system has been shut down uncleanly without any errors, normally, after replaying the committed transactions in the journal, the file system should be marked as clean. Hence, for indicates that further checking is required. -n option is specified, and -c, -l, or -L options are not specified. However, even if it is safe to do % unshare - run program with some namespaces unshared from parent unshare [options] program [arguments] Unshares the indicated namespaces from the parent process and then executes the specified program. The namespaces can optionally be made persistent by bind mounting /proc/pid/ns/type files to a filesystem The namespaces to be unshared are indicated via options. Unshareable namespaces are: mount namespace Mounting and unmounting filesystems will not affect the rest of the system (CLONE_NEWNS flag), except for filesystems which are explicitly marked as shared (with mount --make-shared; see % mechanisms which use the standard libsasl database of user secrets. the -d (delete user) flag. % pinky - lightweight finger pinky [OPTION]... [USER]... -l produce long format output for the specified USERs -b omit the user's home directory and shell in long format -h omit the user's project file in long format -p omit the user's plan file in long format -s do short format output, this is the default -f omit the line of column headings in short format % tic - the terminfo entry-description compiler The tic command translates a terminfo file from source format into compiled format. The compiled format hashed database (one record per entry). The tic command writes only one type of entry, depending on how it was built: · For directory trees, the top-level directory, e.g., /usr/share/terminfo, specifies the location of the database. · For hashed databases, a filename is needed. If the given file is not found by that name, but can be % python - an interpreted, interactive, object-oriented programming language python [ -B ] [ -b ] [ -d ] [ -E ] [ -h ] [ -i ] [ -I ] [ -m module-name ] [ -q ] [ -O ] [ -OO ] [ -s ] [ -S ] [ -u ] [ -v ] [ -V ] [ -W argument ] [ -x ] [ [ -X option ] -? ] [ -c command | script | - ] [ arguments ] Python is an interpreted, interactive, object-oriented programming language that combines remarkable power with very clear syntax. For an introduction to programming in Python, see the Python Tutorial. The Python Library Reference documents built-in and standard types, constants, functions and modules. Finally, the Python Reference Manual describes the syntax and semantics of the core language in (perhaps installed on your system as well.) Python's basic power can be extended with your own modules written in C or C++. On most systems such % troff - the troff processor of the groff text formatting system troff [-abcivzCERU] [-d cs] [-f fam] [-F dir] [-I dir] [-m name] [-M dir] [-n num] [-o list] [-r cn] [-T name] [-w name] [-W name] [file ...] appropriate order and with the appropriate options. It is possible to have whitespace between a command line option and its parameter. -a Generate an ASCII approximation of the typeset output. % gtester - test running utility gtester [OPTION...] [testprogram] gtester is a utility to run unit tests that have been written using the GLib test framework. When called with the -o option, gtester writes an XML report of the test results, which can be converted into HTML using the gtester-report utility. -h, --help print help and exit -v, --version print version information and exit % lexgrog - parse header information in man pages lexgrog [-m|-c] [-dfw?V] [-E encoding] file ... lexgrog is an implementation of the traditional “groff guess” utility in lex. It reads the list of files on its command line as either man page source files or preformatted “cat” pages, and displays their name and description as used by apropos and whatis, the list of preprocessing filters required by the man page before it is passed to nroff or troff, or both. grams that need to check man pages for correctness. If one of lexgrog's input files is “-”, it will read from standard input; if any input file is compressed, a decompressed version will be read automatically. -d, --debug % lvscan — scan (all disks) for Logical Volumes lockingfailure] [-P|--partial] [--reportformat {basic|json}] [-v|--verbose] lvscan scans all known volume groups or all supported LVM block devices in the system for defined Logical Volumes. The output consists of one line for each Logical Volume indicating whether or not it is active, obtain more-comprehensive information about the Logical Volumes. --all Include information in the output about internal Logical Volumes that are components of normally- accessible Logical Volumes, such as mirrors, but which are not independently accessible (e.g. not % msggrep - pattern matching on message catalog msggrep [OPTION] [INPUTFILE] Extracts all messages of a translation catalog that match a given pattern or belong to some given source files. Mandatory arguments to long options are mandatory for short options too. Input file location: INPUTFILE input PO file -D, --directory=DIRECTORY add DIRECTORY to list for input files search % lvmconf — LVM configuration modifier lvmconf [--disable-cluster] [--enable-cluster] [--enable-halvm] [--disable-halvm] [--file ] [--lockinglib ] [--lockinglibdir ] [--services] [--mirrorservice] [--startstopservices] lvmconf is a script that modifies the locking configuration in an lvm configuration file. See lvm configuration if needed. --disable-cluster Set locking_type to the default non-clustered type. Also reset lvmetad use to its default. --enable-cluster Set locking_type to the default clustered type on this system. Also disable lvmetad use as it is % colrm - remove columns from a file colrm [first [last]] colrm removes selected columns from a file. Input is taken from standard input. Output is sent to stan‐ dard output. If called with one parameter the columns of each line will be removed starting with the specified first column. If called with two parameters the columns from the first column to the last column will be removed. -V, --version % ntpdc - vendor-specific NTPD control program ntpdc [-flags] [-flag [value]] [--option-name[[=| ]value]] [ host ...] using a much more sane interface. either in interactive mode or controlled using command line arguments. Extensive state and statistics information is available through the ntpdc interface. In addition, nearly all the configuration options ntpdc. % paste - merge lines of files paste [OPTION]... [FILE]... Write lines consisting of the sequentially corresponding lines from each FILE, separated by TABs, to standard output. With no FILE, or when FILE is -, read standard input. Mandatory arguments to long options are mandatory for short options too. -d, --delimiters=LIST reuse characters from LIST instead of TABs -s, --serial % vgsplit — split a volume group into two vgsplit [--alloc AllocationPolicy] [-A|--autobackup {y|n}] [-c|--clustered {y|n}] [--commandprofile Pro‐ [-p|--maxphysicalvolumes MaxPhysicalVolumes] [--[vg]metadatacopies NumberOfCopies|unmanaged|all] [PhysicalVolumePath...] The physical volumes moved can be specified either explicitly via PhysicalVolumePath, or implicitly by -n moved. for the new volume group can be specified with --alloc, --clustered, --maxlogicalvolumes, --metadatatype, % makepkg - package build utility makepkg [options] [ENVVAR=value] [ENVVAR+=value] ... makepkg is a script to automate the building of packages. The requirements for using the script are a build-capable *nix platform and a custom build script for each package you wish to build (known as a The advantage to a script-based build is that the work is only done once. Once you have the build script for a package, makepkg will do the rest: download and validate source files, check dependencies, configure the build-time settings, build the package, install the package into a temporary root, make customizations, generate meta-info, and package the whole thing up for pacman to use. makepkg uses your current locale by default and does not unset it when building packages. If you wish % mev - a program to report mouse events mev [ options ] The `mev' program is part of the gpm package. The information below is extracted from the texinfo file, which is the preferred source of information. The mev program is modeled after xev. It prints to stdout the mouse console events it gets. mev's default behaviour is to get anything, but command line switches can be used to set the various fields in the Gpm_Connect structure, in order to customize the program's behaviour. I'm using mev to han‐ dle mouse events to Emacs. Command line switches for mev are the following: % last, lastb - show a listing of last logged in users last [options] [username...] [tty...] lastb [options] [username...] [tty...] last searches back through the /var/log/wtmp file (or the file designated by the -f option) and displays a list of all users logged in (and out) since that file was created. One or more usernames and/or ttys be abbreviated, thus last 0 is the same as last tty0. When catching a SIGINT signal (generated by the interrupt key, usually control-C) or a SIGQUIT signal, terminate. The pseudo user reboot logs in each time the system is rebooted. Thus last reboot will show a log of all % mandb - create or update the manual page index caches mandb [-dqsucpt?V] [-C file] [manpath] mandb [-dqsut] [-C file] -f filename ... mandb is used to initialise or manually update index database caches that are usually maintained by man. The caches contain information relevant to the current state of the manual page system and the informa‐ tion stored within them is used by the man-db utilities to enhance their speed and functionality. When creating or updating an index, mandb will warn of bad ROFF .so requests, bogus manual page filenames and manual pages from which the whatis cannot be parsed. Supplying mandb with an optional colon-delimited path will override the internal system manual page hier‐ archy search path, determined from information found within the man-db configuration file. % showconsolefont - Show the current EGA/VGA console screen font showconsolefont [ -V ] [ -v ] [ -C console ] The showconsolefont command outputs the current console font to stdout. The option -v prints additional -C allows one to indicate the console involved. Its argument is a pathname. % lnstat - unified linux network statistics lnstat [options] lnstat is a generalized and more feature-complete replacement for the old rtstat program. It is commonly used to periodically print a selection of statistical values exported by the kernel. In addition to routing cache statistics, it supports any kind of statistics the linux kernel exports via a file in /proc/net/stat/. Each file in /proc/net/stat/ contains a header line listing the column names. These names are used by lnstat as keys for selecting which statistics to print. For every CPU present in the system, a line fol‐ lows which lists the actual values for each column of the file. lnstat sums these values up (which in fact are counters) before printing them. After each interval, only the difference to the last value is % gzexe - compress executable files in place gzexe name ... The gzexe utility allows you to compress executables in place and have them automatically uncompress and execute when you run them (at a penalty in performance). For example if you execute ``gzexe /usr/bin/gdb'' it will create the following two files: /usr/bin/gdb~ is the original file and /usr/bin/gdb is the self-uncompressing executable file. You can remove /usr/bin/gdb~ once you are sure that /usr/bin/gdb works properly. % recode-sr-latin - convert Serbian text from Cyrillic to Latin script recode-sr-latin [OPTION] Recode Serbian text from Cyrillic to Latin script. The input text is read from standard input. The con‐ verted text is output to standard output. Informative output: -h, --help display this help and exit -V, --version output version information and exit % nice - run a program with modified scheduling priority the process). Mandatory arguments to long options are mandatory for short options too. -n, --adjustment=N --help display this help and exit % zforce - force a '.gz' extension on all gzip files zforce [ name ... ] % lwresd - lightweight resolver daemon lwresd [-c config-file] [-C config-file] [-d debug-level] [-f] [-g] [-i pid-file] [-m flag] [-n #cpus] lwresd is the daemon providing name lookup services to clients that use the BIND 9 lightweight resolver library. It is essentially a stripped-down, caching-only name server that answers queries using the BIND 9 lightweight resolver protocol rather than the DNS protocol. is used for lightweight resolver requests and responses. Incoming lightweight resolver requests are decoded by the server which then resolves them using the DNS protocol. When the DNS lookup completes, lwresd encodes the answers in the lightweight resolver format % tput, reset - initialize a terminal or query terminfo database tput [-Ttype] capname [parms ... ] tput [-Ttype] init tput [-Ttype] reset tput [-Ttype] longname tput -S << tput -V The tput utility uses the terminfo database to make the values of terminal-dependent capabilities and name of the requested terminal type. The result depends upon the capability's type: string tput writes the string to the standard output. No trailing newline is supplied. % xfs_estimate - estimate the space that an XFS filesystem will take xfs_estimate [ -h ] [ -b blocksize ] [ -i logsize ] [ -e logsize ] [ -v ] directory ... xfs_estimate -V For each directory argument, xfs_estimate estimates the space that directory would take if it were copied to an XFS filesystem. xfs_estimate does not cross mount points. The following definitions are used: The xfs_estimate options are: -b blocksize % request-key - Handle key instantiation callback requests from the kernel /sbin/request-key [] available. The kernel creates a partially set up key and then calls out to this program to instantiate it. It is not intended to be called directly. ERRORS All errors will be logged to the syslog. FILES /etc/request-key.conf Instantiation handler configuration file. /etc/request-key.d/.conf Keytype specific configuration file. % vlock - Virtual Console lock program vlock vlock [ -a,--all ] [ -c,--current ] [ -h,--help ] [ -v,--version ] sion(s) while still allowing other users to use the system on other virtual consoles. If desired, the By default, only the current VC (virtual console) is locked. With the -a,-all option all VCs are locked. The locked VCs cannot be unlocked without the invoker's password. And, for the paranoid, vlock makes it a trying experience for those attempting to guess the password, so unauthorized access to session(s) is highly unlikely. % psfxtable - handle Unicode character tables for console fonts psfxtable [-i infont] [-o outfont] [-it intable] [-ot outtable] [-nt] psfxtable handles the embedded Unicode character table for .psf format console fonts. It reads a font and are links to it. standard input. If no -it or -o or -ot option is given, no input table is read or no output font or out‐ put table is written. By default the output font (if any) will have a Unicode table when either the input font has one, or an explicit table (which overrides an input font table) has been provided. The option -nt causes output of % kmod - Program to manage Linux Kernel modules kmod is a multi-call binary which implements the programs used to control Linux Kernel modules. Most users will only run it using its other names. -V --version Show the program version and exit. -h --help Show the help message. % vimdiff - edit two, three or four versions of a file with Vim and show differences gvimdiff Vimdiff starts Vim on two (or three or four) files. Each file gets its own window. The differences version to another version of the same file. When started as gvimdiff the GUI will be started, if available. In each window the 'diff' option will be set, which causes the differences to be highlighted. % dnssec-verify - DNSSEC zone verification tool dnssec-verify [-c class] [-E engine] [-I input-format] [-o origin] [-v level] [-V] [-x] [-z] {zonefile} dnssec-verify verifies that a zone is fully signed for each algorithm found in the DNSKEY RRset for the -c class Specifies the DNS class of the zone. -E engine Specifies the cryptographic hardware to use, when applicable. % vgcreate — create a volume group vgcreate [--addtag Tag] [--alloc AllocationPolicy] [-A|--autobackup {y|n}] [-c|--clustered {y|n}] [--com‐ datacopies NumberOfCopies|unmanaged|all] [-s|--physicalextentsize PhysicalExtentSize[bBsSkKmMgGtTpPeE]] [--reportformat {basic|json}] [--shared] [--systemid SystemID] [-t|--test] [-v|--verbose] [--version] cePath. % expiry - check and enforce password expiration policy expiry option The expiry command checks (-c) the current password expiration and forces (-f) changes when required. It is callable as a normal user command. The options which apply to the expiry command are: -c, --check Check the password expiration of the current user. -f, --force Force a password change if the current user has an expired password. % vconfig [lots of long options] The vconfig program allows you to create and remove vlan-devices on a vlan enabled kernel. Vlan-devices are virtual ethernet devices which represents the virtual lans on the physical lan. add [interface-name] [vlan-id] Creates a vlan-device on [interface-name]. The resulting vlan-device will be called according to the nameing convention set. rem [vlan-device] Removes the named vlan-device. % lvmetad — LVM metadata cache daemon lvmetad [-l level[,level...]] [-p pidfile_path] [-s socket_path] [-t timeout_value] [-f] [-h] [-V] [-?] The lvmetad daemon caches LVM metadata so that LVM commands can read metadata from the cache rather than the normal work of the system. lvmetad can be a disadvantage when disk event notifications from the sys‐ tem are unreliable. lvmetad does not read metadata from disks itself. Instead, it relies on an LVM command, like pvscan --cache, to read metadata from disks and send it to lvmetad to be cached. New LVM disks that appear on the system must be scanned before lvmetad knows about them. If lvmetad does not know about a disk, then LVM commands using lvmetad will also not know about it. When disks are added or removed from the system, lvmetad must be updated. % repo-add - package database maintenance utility repo-add [options] [ ...] repo-remove [options] [ ...] repo-add and repo-remove are two scripts to help build a package database for packages built with repo-add will update a package database by reading a built package or package delta file. Multiple packages and/or deltas to add can be specified on the command line. If a matching “.sig” file is found alongside a package file, the signature will automatically be embedded into the database. % c++filt - Demangle C++ and Java symbols. c++filt [-_|--strip-underscore] [-n|--no-strip-underscore] [-p|--no-params] [-t|--types] [-i|--no-verbose] [-s format|--format=format] [--help] [--version] [symbol...] The C++ and Java languages provide function overloading, which means that you can write many functions with the same name, providing that each function takes parameters of different types. In order to be able to distinguish these similarly named functions C++ and Java encode them into a low-level assembler % pkexec - Execute a command as another user pkexec [--version] [--disable-internal-agent] [--help] pkexec allows an authorized user to execute PROGRAM as another user. If PROGRAM is not specified, the default shell will be run. If username is not specified, then the program will be executed as the administrative super user, root. RETURN VALUE Upon successful completion, the return value is the return value of PROGRAM. If the calling process is not authorized or an authorization could not be obtained through authentication or an error occured, % du - estimate file space usage du [OPTION]... [FILE]... du [OPTION]... --files0-from=F Summarize disk usage of the set of FILEs, recursively for directories. Mandatory arguments to long options are mandatory for short options too. -0, --null end each output line with NUL, not newline -a, --all write counts for all files, not just directories % There is an additional drawing command available: \D'R dh dv' Draw a rule (solid black rectangle), with one corner at the current position, and the diagonally opposite corner at the current position +(dh,dv). Afterwards the current position will be at the % gperl - groff preprocessor for Perl parts in roff files gperl [-] [--] [ filespec ....] gperl -h|--help gperl -v|--version Perl part can be stored in groff strings or numerical registers based on the arguments at a final line of a Perl part. So far, there are only filespec or breaking options. filespec are file names or the minus character - character for standard input. As usual, the argument -- can be used in order to let all fowllowing arguments mean file names, even if the names begin with a % git - the stupid content tracker git [--version] [--help] [-C ] [-c =] [--exec-path[=]] [--html-path] [--man-path] [--info-path] [-p|--paginate|--no-pager] [--no-replace-objects] [--bare] [--git-dir=] [--work-tree=] [--namespace=] [] Git is a fast, scalable, distributed revision control system with an unusually rich command set that provides both high-level operations and full access to internals. See gittutorial(7) to get started, then see giteveryday(7) for a useful minimum set of commands. The Git After you mastered the basic concepts, you can come back to this page to learn what commands Git offers. % igawk - gawk with include files igawk [ all gawk options ] -f program-file [ -- ] file ... igawk [ all gawk options ] [ -- ] program-text file ... @include getopt.awk in your program to include the file getopt.awk from either the current directory or one of the other directories in the search path. % nl-classid-lookup - Lookup classid definitions nl-classid-lookup [-hv] [-r] [--raw] name nl-classid-lookup searches the classid database for a matching entry. It is used to resolve qdisc/class names to classid values and vice versa. -h or --help Print help text to console and exit. -v or --version Print versioning information to console and exit. -r or --reverse % host - DNS lookup utility {name} [server] host is a simple utility for performing DNS lookups. It is normally used to convert names to IP addresses and vice versa. When no arguments or options are given, host prints a short summary of its command line arguments and options. address. server is an optional argument which is either the name or IP address of the name server that host should query instead of the server or servers listed in /etc/resolv.conf. % stty - change and print terminal line settings stty [-F DEVICE | --file=DEVICE] [SETTING]... stty [-F DEVICE | --file=DEVICE] [-a|--all] stty [-F DEVICE | --file=DEVICE] [-g|--save] Print or change terminal characteristics. Mandatory arguments to long options are mandatory for short options too. -a, --all print all current settings in human-readable form -g, --save print all current settings in a stty-readable form % rarpd - answer RARP REQUESTs arping [-aAvde] [-b bootdir] [interface] is found in /etc/ethers database and obtained host name is resolvable to an IP address appropriate for attached network, rarpd answers to client with RARPD reply carrying an IP address. To allow multiple boot servers on the network rarpd optionally checks for presence Sun-like bootable im‐ WARNING % swapon, swapoff - enable/disable devices and files for paging and swapping swapon [options] [specialfile...] swapoff [-va] [specialfile...] swapon is used to specify devices on which paging and swapping are to take place. to indicate a device by label or uuid. Calls to swapon normally occur in the system boot scripts making all swap devices available, so that the paging and swapping activity is interleaved across several devices and files. swapoff disables swapping on the specified devices and files. When the -a flag is given, swapping is disabled on all known swap devices and files (as found in /proc/swaps or /etc/fstab). % dnssec-settime - set the key timing metadata for a DNSSEC key dnssec-settime [-f] [-K directory] [-L ttl] [-P date/offset] [-P sync date/offset] [-A date/offset] [-R date/offset] [-I date/offset] [-D date/offset] [-D sync date/offset] [-h] [-V] [-v level] [-E engine] {keyfile} dnssec-settime reads a DNSSEC private key file and sets the key timing metadata as specified by the -P, -A, -R, -I, and -D options. The metadata can then be used by dnssec-signzone or other signing software to determine when a key is to be published, whether it should be used for signing a zone, etc. If none of these options is set on the command line, then dnssec-settime simply prints the key timing metadata already stored in the key. When key metadata fields are changed, both files of a key pair (Knnnn.+aaa+iiiii.key and Knnnn.+aaa+iiiii.private) are regenerated. Metadata fields are stored in the private file. A % systemd-path - List and query system and user paths file-hierarchy(7) available for querying. When invoked without arguments, a list of known paths and their current values is shown. When at least one argument is passed, the path with this name is queried and its value shown. The variables whose name begins with "search-" do not refer to individual paths, but instead to a list of colon-separated search paths, in their order of precedence. The following options are understood: % cfdisk - display or manipulate a disk partition table cfdisk [options] [device] cfdisk is a curses-based program for partitioning any block device. The default device is /dev/sda. functionality for CHS (Cylinder-Head-Sector) addressing. CHS has never been important for Linux, and this addressing concept does not make any sense for new devices. % setsid - run a program in a new session setsid [options] program [arguments] setsid runs a program in a new session. -c, --ctty Set the controlling terminal to the current one. -w, --wait Wait for the execution of the program to end, and return the exit value of this program as the return value of setsid. -V, --version % xfs_freeze - suspend access to an XFS filesystem xfs_freeze [ -f | -u ] mount-point xfs_freeze -V xfs_freeze halts new access to the filesystem and creates a stable image on disk. xfs_freeze is intended to be used with volume managers and hardware RAID devices that support the creation of snapshots. The mount-point argument is the pathname of the directory where the filesystem is mounted. The filesys‐ The -f flag requests the specified XFS filesystem to be frozen from new modifications. When this is selected, all ongoing transactions in the filesystem are allowed to complete, new write system calls are % dc - an arbitrary precision calculator dc [-V] [--version] [-h] [--help] [-e scriptexpression] [--expression=scriptexpression] [-f scriptfile] [--file=scriptfile] [file ...] dc is a reverse-polish desk calculator which supports unlimited precision arithmetic. It also allows you to define and call macros. Normally dc reads from the standard input; if any command arguments are given to it, they are filenames, and dc reads and executes the contents of the files before reading from stan‐ dard input. All normal output is to standard output; all error output is to standard error. A reverse-polish calculator stores numbers on a stack. Entering a number pushes it on the stack. Arith‐ metic operations pop arguments off the stack and push the results. % xfs_mdrestore - restores an XFS metadump image to a filesystem image xfs_mdrestore [ -g ] source target xfs_mdrestore -V filesystem. The source argument specifies the location of the metadump image and the target argument specifies the destination for the filesystem image. If the source is -, then the metadata image is read rected to xfs_mdrestore. The target can be either a file or a device. xfs_mdrestore should not be used to restore metadata onto an existing filesystem unless you are com‐ pletely certain the target can be destroyed. % ssh-keyscan — gather ssh public keys ssh-keyscan is a utility for gathering the public ssh host keys of a number of hosts. It was designed to aid in building and verifying ssh_known_hosts files. ssh-keyscan provides a minimal interface suitable for use by shell and perl scripts. ssh-keyscan uses non-blocking socket I/O to contact as many hosts as possible in parallel, so it is very those hosts are down or do not run ssh. For scanning, one does not need login access to the machines that are being scanned, nor does the scanning process involve any encryption. The options are as follows: % RR in it and it will create a .ds file with the DS RR in it. It prints out the basename for this file (K++). -f Ignore SEP flag (i.e. make DS records for any key) -n Write the result DS Resource Record to stdout instead of a file % rev - reverse lines characterwise rev [option] [file...] The rev utility copies the specified files to standard output, reversing the order of characters in every line. If no files are specified, standard input is read. -V, --version Display version information and exit. -h, --help Display help text and exit. % hostnamectl - Control the system hostname all kinds of special characters (e.g. "Lennart's Laptop"), the static hostname which is used to initialize the kernel hostname at boot (e.g. "lennarts-laptop"), and the transient hostname which is a fallback value received from network configuration. If a static hostname is set, and is valid (something other than localhost), then the transient hostname is not used. transient hostnames are limited to the usually accepted characters of Internet domain names. % vim - Vi IMproved, a programmers text editor vim [options] [file ..] vim [options] - vim [options] -t tag vim [options] -q [errorfile] ex view gvim gview evim eview rvim rview rgvim rgview Vim is a text editor that is upwards compatible to Vi. It can be used to edit all kinds of plain text. It is especially useful for editing programs. % dnssec-signzone - DNSSEC zone signing tool dnssec-signzone [-a] [-c class] [-d directory] [-D] [-E engine] [-e end-time] [-f output-file] [-g] [-h] [-K directory] [-k key] [-L serial] [-l domain] [-M domain] [-i interval] [-I input-format] [-j jitter] [-N soa-serial-format] [-o origin] [-O output-format] [-P] [-p] [-Q] [-R] [-r randomdev] [-S] [-s start-time] [-T ttl] [-t] [-u] [-v level] [-V] dnssec-signzone signs a zone. It generates NSEC and RRSIG records and produces a signed version of the zone. The security status of delegations from the signed zone (that is, whether the child zones are secure or not) is determined by the presence or absence of a keyset file for each child zone. -a Verify all generated signatures. % nl-pktloc-lookup - Lookup packet location definitions nl-pktloc-lookup name nl-pktloc-lookup --list nl-pktloc-lookup searches the packet location database for a matching entry. It is used to resolve packet location aliases to their definition, i.e. alignment, layer, offset, and mask. -h or --help Print help text to console and exit. -v or --version Print versioning information to console and exit. % strip - Discard symbols from object files. strip [-F bfdname |--target=bfdname] [-I bfdname |--input-target=bfdname] [-O bfdname |--output-target=bfdname] [-s|--strip-all] [-S|-g|-d|--strip-debug] [--strip-dwo] [-K symbolname |--keep-symbol=symbolname] [-N symbolname |--strip-symbol=symbolname] [-w|--wildcard] [-x|--discard-all] [-X |--discard-locals] [-R sectionname |--remove-section=sectionname] [-o file] [-p|--preserve-dates] [-D|--enable-deterministic-archives] [-U|--disable-deterministic-archives] % ldns-keyfetcher - retrieve the DNSSEC DNSKEYs for a zone ldns-keyfetcher is used to retrieve the DNSKEYs of a zone. First it finds all authoritative nameservers of the zone by tracing it from the root down. All authorita‐ tive nameservers are then queried (using TCP) for the DNSKEY RRset of the zone apex. If the results are all the same, the key resource record set is printed. -6 Only use IPv6 % makepkg-template - package build templating utility makepkg-template [options] makepkg-template is a script to ease the work of maintaining multiple similar PKGBUILDs. It allows you to move most of the code from the PKGBUILD into a template file and uses markers to allow in-place updating of existing PKGBUILDs if the template has been changed. Template files can contain any code allowed in a PKGBUILD. You can think of them like external files included with "." or "source", but they will be inlined into the PKGBUILD by makepkg-template so you do not depend on the template file when building the package. Markers are bash comments in the form of: % chpasswd - update passwords in batch mode chpasswd [options] The chpasswd command reads a list of user name and password pairs from standard input and uses this information to update a group of existing users. Each line is of the format: user_name:password By default the passwords must be supplied in clear-text, and are encrypted by chpasswd. Also the password age will be updated, if present. By default, passwords are encrypted by PAM, but (even if not recommended) you can select a different encryption method with the -e, -m, or -c options. % autoheader - Create a template header for configure autoheader [OPTION]... [TEMPLATE-FILE] Create a template file of C `#define' statements for `configure' to use. To this end, scan TEM‐ PLATE-FILE, or `configure.ac' if present, or else `configure.in'. -h, --help print this help, then exit -V, --version print version number, then exit -v, --verbose verbosely report processing % ldns-gen-zone - read a zonefile and print it while adding DS records and extra RR's ldns-gen-zone ZONEFILE ldns-gen-zone reads a DNS zone file and prints it. It is build for speed, not for a nice formatting. The output has one resource record per line and no pretty-printing makeup. Existing DS records are also not stripped. The idea is to use this tool for quickly generating a representative artificial zonefile from a real zonefile, to use it for testing purposes. % infocmp - compare or print out terminfo descriptions [-v n] [-s d| i| l| c] [-R subset] [-w width] [-A directory] [-B directory] [termname...] infocmp can be used to compare a binary terminfo entry with other terminfo entries, rewrite a terminfo description to take advantage of the use= terminfo field, or print out a terminfo description from the lowed by the numeric fields, followed by the string fields. Default Options If no options are specified and zero or one termnames are specified, the -I option will be assumed. If more than one termname is specified, the -d option will be assumed. % xz, unxz, xzcat, lzma, unlzma, lzcat - Compress or decompress .xz and .lzma files xz [option...] [file...] unxz is equivalent to xz --decompress. xzcat is equivalent to xz --decompress --stdout. lzma is equivalent to xz --format=lzma. unlzma is equivalent to xz --format=lzma --decompress. lzcat is equivalent to xz --format=lzma --decompress --stdout. When writing scripts that need to decompress files, it is recommended to always use the name xz with appropriate arguments (xz -d or xz -dc) instead of the names unxz and xzcat. % damaged filesystem. requirement can be overridden using the -f option, but the resulting image file is very likely not going % cksum - checksum and count the bytes in a file cksum [FILE]... cksum [OPTION] Print CRC checksum and byte counts of each FILE. --help display this help and exit --version output version information and exit Written by Q. Frank Xia. % the system. See the various sub commands below. The following global options can be used: -v, --verbose Run in verbose mode with debug output. -q, --quiet % -a number -s salt Use the given salt for the hash calculation. Salt value should be in hexadecimal format. -t count Use count iterations for the hash calculation. % pkgdelta - package delta generation utility pkgdelta is used to create package delta files between two versions of the same package. These files are with the previous versions of packages (in the package cache) to synthesize the upgraded version of the --max-delta-size Only create delta files if the delta is smaller than ratio * package_size. Possible values: 0.0 to % visudo — edit the sudoers file visudo [-chqsV] [-f sudoers] [-x output_file] against multiple simultaneous edits, provides basic sanity checks, and checks for parse errors. If the sudoers file is currently being edited you will receive a message to try again later. honor the VISUAL or EDITOR environment variables unless they contain an editor in the aforementioned edi‐ tors list. However, if visudo is configured with the --with-env-editor option or the env_editor Default be a security hole since it allows the user to execute any program they wish simply by setting VISUAL or EDITOR. % fsck - check and repair a Linux filesystem fsck [-lsAVRTMNP] [-r [fd]] [-C [fd]] [-t fstype] [filesystem...] [--] [fs-specific-options] fsck is used to check and optionally repair one or more Linux filesystems. filesys can be a device name handle filesystems on different physical disk drives in parallel to reduce the total amount of time needed to check all of them. If no filesystems are specified on the command line, and the -A option is not specified, fsck will The exit code returned by fsck is the sum of the following conditions: % zcmp, zdiff - compare compressed files Zcmp and zdiff are used to invoke the cmp or the diff program on files compressed via gzip. All options fed to cmp or diff. The input files are not modified. The exit status from cmp or diff is preserved. BUGS % chattr - change file attributes on a Linux file system chattr [ -RVf ] [ -v version ] [ -p project ] [ mode ] files... chattr changes the file attributes on a Linux file system. The format of a symbolic mode is +-=[aAcCdDeijsStTu]. The operator '+' causes the selected attributes to be added to the existing attributes of the files; '-' causes them to be removed; and '=' causes them to be the only attributes that the files have. The letters 'aAcCdDeijsStTu' select the new attributes for the files: append only (a), no atime updates (A), compressed (c), no copy on write (C), no dump (d), synchronous directory updates (D), extent format (e), immutable (i), data journalling (j), project hierarchy (P), secure deletion (s), synchronous updates (S), no tail-merging (t), top of directory hierarchy (T), and undeletable (u). % scmp_sys_resolver - Resolve system calls in the optional ARCH argument. If the architecture is not supplied on the command line then the native architecture is used. If the "-t" argument is specified along with a system call name, then the system call will be translated as necessary for the given architecture. The "-t" argument has no effect if a system call number is specified. In some combinations of architecture and system call, a negative system call number will be displayed. A negative system call number indicates that the system call is not defined for the given architecture and is treated in a special manner by libseccomp depending on the operation. -a ARCH % pfbtops - translate a PostScript font in .pfb format to ASCII pfbtops [ -v ] [ pfb_file ] pfbtops translates a PostScript font in .pfb format to ASCII, splitting overlong lines in text packets into smaller chunks. If pfb_file is omitted the pfb file will be read from the standard input. The ASCII format PostScript font will be written on the standard output. PostScript fonts for MS-DOS are normally supplied in .pfb format. The resulting ASCII format PostScript font can be used with groff. It must first be listed in -v Print the version number. % fsck.xfs - do nothing, successfully fsck.xfs [ filesys ... ] exits with a zero exit status. If you wish to check the consistency of an XFS filesystem, or repair a damaged or corrupt XFS filesystem, FILES /etc/fstab. % getfattr - get extended attributes of filesystem objects getfattr [-hRLP] -n name [-e en] pathname... getfattr [-hRLP] -d [-e en] [-m pattern] pathname... For each file, getfattr displays the file name, and the set of extended attribute names (and optionally values) which are associated with that file. The output format of getfattr -d is as follows: % gdbmtool - examine and modify a GDBM database gdbmtool [-lmNnqrs] [-b SIZE] [-c SIZE] [-f FILE] [--block-size=SIZE] [--cache-size=SIZE] [--file FILE] [--newdb] [--no-lock] [--no-mmap] [--norc] [--quiet] [--read-only] [--synchronize] [DBFILE] gdbmtool [-Vh] ][--help] [--usage] [--version] The gdbmtool utility allows you to view and modify an existing GDBM database or to create a new one. The DBFILE argument supplies the name of the database to open. If not supplied, the default name junk.gdbm is used instead. If the named database does not exist, it will be created. An existing data‐ base can be cleared (i.e. all records removed from it) using the --newdb option (see below). % logrotate ‐ rotates, compresses, and mails system logs logrotate [-dv] [-f|--force] [-s|--state file] config_file .. logrotate is designed to ease administration of systems that generate large numbers of log files. It daily, weekly, monthly, or when it grows too large. Normally, logrotate is run as a daily cron job. It will not modify a log more than once in one day unless the criterion for that log is based on the log's size and logrotate is being run more than once each day, or unless the -f or --force option is used. given in earlier files, so the order in which the logrotate config files are listed is important. Nor‐ mally, a single config file which includes any other config files which are needed should be used. See % kadmin [-O|-N] [-r realm] [-p principal] [-q query] [[-c cache_name]|[-k [-t keytab]]|-n] [-w password] [-s admin_server[:port]] kadmin.local [-r realm] [-p principal] [-q query] [-d dbname] [-e enc:salt ...] [-m] [-x db_args] vide nearly identical functionalities; the difference is that kadmin.local directly accesses the KDC man page will use "kadmin" to refer to both versions. kadmin provides for the maintenance of Kerberos principals, password policies, and service key tables (keytabs). The remote kadmin client uses Kerberos to authenticate to kadmind using the service principal kad‐ min/ADMINHOST (where ADMINHOST is the fully-qualified hostname of the admin server) or kadmin/admin. If % grub-editenv - edit GRUB environment block Tool to edit environment block. Commands: create Create a blank environment block file. list List the current variables. Set variables. % pwd - print name of current/working directory pwd [OPTION]... Print the full filename of the current working directory. -L, --logical use PWD from environment, even if it contains symlinks -P, --physical avoid all symlinks --help display this help and exit --version % setleds - set the keyboard leds setleds [-v] [-L] [-D] [-F] [{+|-}num] [{+|-}caps] [{+|-}scroll] Setleds reports and changes the led flag settings of a VT (namely NumLock, CapsLock and ScrollLock). Without arguments, setleds prints the current settings. With arguments, it sets or clears the indicated flags (and leaves the others unchanged). The settings before and after the change are reported if the -v flag is given. The led flag settings are specific for each VT (and the VT corresponding to stdin is used). by the keyboard leds). With option -D, setleds will change both the VT flags and their default settings (so that a subsequent % jfs_mkfs - create a JFS formatted partition jfs_mkfs [options] device [ blocks ] jfs_mkfs is used to create (format) a JFS partition. jfs_mkfs must be run as root. system and/or JFS journal will be created. blocks is the number of blocks to be used for the file sys‐ tem. If omitted, jfs_mkfs automatically figures the file system size. WARNING jfs_mkfs will destroy all data on the specified device! % getopt - parse command options (enhanced) getopt optstring parameters getopt [options] [--] optstring parameters getopt [options] -o|--options optstring [options] [--] parameters getopt is used to break up (parse) options in command lines for easy parsing by shell procedures, and to The parameters getopt is called with can be divided into two parts: options which modify the way getopt is not an option argument, or after the first occurrence of '--'. If no '-o' or '--options' option is found in the first part, the first parameter of the second part is used as the short options string. % lvchange — change attributes of a logical volume lvchange [-a|--activate [a][e|s|l]{y|n}] [--activationmode {complete|degraded|partial}] [--addtag Tag] [-K|--ignoreactivationskip] [-k|--setactivationskip {y|n}] [--alloc AllocationPolicy] [-A|--autobackup {y|n}] [--rebuild PhysicalVolume] [--cachemode {passthrough|writeback|writethrough}] [--cachepolicy Pol‐ [--deltag Tag] [--detachprofile] [--discards {ignore|nopassdown|passdown}] [--errorwhenfull {y|n}] [-h|-?|--help] [--ignorelockingfailure] [--ignoremonitoring] [--ignoreskippedcluster] [--metadataprofile {y|n} [--major Major] [--minor Minor]] [--poll {y|n}] [--[raid]maxrecoveryrate Rate] [--[raid]minrecov‐ eryrate Rate] [--[raid]syncaction {check|repair}] [--[raid]writebehind IOCount] [--[raid]writemostly PhysicalVolume[:{y|n|t}]] [-r|--readahead {ReadAheadSectors|auto|none}] [--refresh] [--reportformat {basic|json}] [--resync] [-S|--select Selection] [--sysinit] [-t|--test] [-v|--verbose] [-Z|--zero {y|n}] [LogicalVolumePath...] % df - report file system disk space usage df [OPTION]... [FILE]... file system containing each file name argument. If no file name is given, the space available on all If an argument is the absolute file name of a disk device node containing a mounted file system, df shows version of df cannot show the space available on unmounted file systems, because on most kinds of systems doing so requires very nonportable intimate knowledge of file system structures. % depmod - Generate modules.dep and map files. depmod [-b basedir] [-e] [-E Module.symvers] [-F System.map] [-n] [-v] [-A] [-P prefix] [-w] [version] depmod [-e] [-E Module.symvers] [-F System.map] [-m] [-n] [-v] [-P prefix] [-w] [version] [filename...] Linux kernel modules can provide services (called "symbols") for other modules to use (using one of the EXPORT_SYMBOL variants in the code). If a second module uses this symbol, that second module clearly depends on the first module. These dependencies can get quite complex. depmod creates a list of module dependencies by reading each module under /lib/modules/version and determining what symbols it exports and what symbols it needs. By default, this list is written to modules.dep, and a binary hashed version named modules.dep.bin, in the same directory. If filenames are given on the command line, only those modules are examined (which is rarely useful unless all modules are listed). depmod also creates a list of symbols provided by modules in the file named modules.symbols and % peekfd - peek at file descriptors of running processes [-h,--help] pid [fd] [fd] ... peekfd attaches to a running process and intercepts all reads and writes to file descriptors. You can specify the desired file descriptor numbers or dump all of them. -n Do not display headers indicating the source of the bytes dumped. -c Also dump the requested file descriptor activity in any new child processes that are created. % faillog - display faillog records or set login failure limits faillog [options] faillog displays the contents of the failure log database (/var/log/faillog). It can also set the failure counters and limits. When faillog is run without arguments, it only displays the faillog records of the users who had a login failure. The options which apply to the faillog command are: -a, --all Display (or act on) faillog records for all users having an entry in the faillog database. The range of users can be restricted with the -u option. % btrfs-inspect-internal - query various internal information btrfs inspect-internal simple UI to an ioctl or a more complex query that assembles the result from several internal structures. The latter usually requires calls to privileged ioctls. dump-super [options] [device...] (replaces the standalone tool btrfs-show-super) Show btrfs superblock information stored on given devices in textual form. By default the first superblock is printed, more details about all copies or additional backup data can be printed. % login - begin session on the system login [ -p ] [ -h host ] [ -H ] [ -f username | username ] login is used when signing onto a system. If no argument is given, login prompts for the username. The user is then prompted for a password, where approprate. Echoing is disabled to prevent revealing the password. Only a small number of password failures are permitted before login exits and the communica‐ tions link is severed. proceeding. He will be forced to provide his old password and the new password before continuing. The user and group ID will be set according to their values in the /etc/passwd file. There is one excep‐ % grub-mknetdir - prepare a GRUB netboot directory. grub-mknetdir [OPTION...] --compress=no|xz|gz|lzo compress GRUB files [optional] -d, --directory=DIR use images and modules under DIR [default=/usr/lib/grub/] --fonts=FONTS install FONTS [default=unicode] --install-modules=MODULES install only MODULES and their dependencies [default=all] % Reads an EQN equation (one line) as input; produces an image file (by default in Portable Network Graph‐ ics format) suitable for the Web as output. macros; nor do you need to have dollar-sign or other delimiters around the equation. The output image will be clipped to the smallest possible bounding box that contains all the black pix‐ border, force the background transparent, set the image's pixel density, or perform other useful trans‐ formations. % shutdown - Halt, power-off or reboot the machine wall message to be sent to all logged-in users before going down. specified number of minutes m from now. "now" is an alias for "+0", i.e. for triggering an immediate % hddtemp - Utility to monitor hard drive temperature hddtemp [options] [type:]disk... hddtemp will give you the temperature of your hard drive by reading Self-Monitoring Analysis and Report‐ ing Technology (S.M.A.R.T.) information on drives that support this feature. Only modern hard drives have a temperature sensor. hddtemp supports reading S.M.A.R.T. information from SCSI drives too. hddtemp can work as simple command line tool or as a daemon. You can specify one or more device drive path, where each path can be prefixed with a type like PATA, SATA or SCSI to force hddtemp too use one of these type (because detection can fail). The program follows the usual GNU command line syntax, with long options starting with two dashes (`-'). A summary of options is included below. % dhcpcd — a DHCP client [-F, --fqdn FQDN] [-f, --config file] [-h, --hostname hostname] [-I, --clientid clientid] [-i, --vendorclassid vendorclassid] [-j, --logfile logfile] [-l, --leasetime seconds] [-m, --metric metric] [-O, --nooption option] [-o, --option option] [-Q, --require option] [-r, --request address] [-S, --static value] [-s, --inform address[/cidr]] [--inform6] [-t, --timeout seconds] [-u, --userclass class] [-v, --vendor code, value] [-X, --blacklist address[/cidr]] [-Z, --denyinterfaces pattern] [-z, --allowinterfaces pattern] [--inactive] [interface] [...] dhcpcd -n, --rebind [interface] dhcpcd -k, --release [interface] dhcpcd -U, --dumplease interface dhcpcd --version dhcpcd -x, --exit [interface] % grodvi - convert groff output to TeX dvi format grodvi [ -dlv ] [ -Fdir ] [ -ppapersize ] [ -wn ] [ files... ] It is possible to have whitespace between a command line option and its parameter. grodvi is a driver for groff that produces TeX dvi format. Normally it should be run by groff -Tdvi. The dvi file generated by grodvi can be printed by any correctly-written dvi driver. The troff drawing \D commands will not produce any output. There is an additional drawing command available: % znew - recompress .Z files to .gz files znew [ -ftv9PK] [ name.Z ... ] Znew recompresses files from .Z (compress) format to .gz (gzip) format. If you want to recompress a file already in gzip format, rename the file to force a .Z extension then apply znew. -f Force recompression from .Z to .gz format even if a .gz file already exists. -t Tests the new files before deleting originals. -v Verbose. Display the name and percentage reduction for each file compressed. -9 Use the slowest compression method (optimal compression). % od - dump files in octal and other formats od [OPTION]... [FILE]... od [-abcdfilosx]... [FILE] [[+]OFFSET[.][b]] od --traditional [OPTION]... [FILE] [[+]OFFSET[.][b] [+][LABEL][.][b]] Write an unambiguous representation, octal bytes by default, of FILE to standard output. With more than one FILE argument, concatenate them in the listed order to form the input. With no FILE, or when FILE is -, read standard input. If first and second call formats both apply, the second format is assumed if the last operand begins with at first byte printed, incremented when dump is progressing. For OFFSET and LABEL, a 0x or 0X prefix % thin_ls - List thin volumes within a pool. thin_ls [options] {metadata device} thin_ls Displays infomation about thin volumes in a pool. Pass the metadata device on the command line, not the pool device. -o, --format Give a comma separated list of the fields to be output. Valid fields are: DEV, MAPPED_BLOCKS, EXCLUSIVE_BLOCKS, SHARED_BLOCKS, MAPPED_SECTORS, EXCLUSIVE_SECTORS, SHARED_SECTORS, MAPPED_BYTES, EXCLUSIVE_BYTES, SHARED_BYTES, MAPPED, EXCLUSIVE, SHARED, TRANSACTION CREATE_TIME, SNAP_TIME % pwconv, pwunconv, grpconv, grpunconv - convert to and from shadow passwords and groups pwconv [options] pwunconv [options] grpconv [options] grpunconv [options] The pwconv command creates shadow from passwd and an optionally existing shadow. The pwunconv command creates passwd from passwd and shadow and then removes shadow. The grpconv command creates gshadow from group and an optionally existing gshadow. % pivot_root - change the root filesystem pivot_root new_root put_old pivot_root moves the root file system of the current process to the directory put_old and makes new_root the latter for further details. pivot_root and chroot are in the current PATH: cd new_root pivot_root . put_old exec chroot . command % | --defcktname | --cflags | --libs [libraries]] installed Kerberos libraries. --all prints the version, vendor, prefix, and exec-prefix. --version prints the version number of the Kerberos installation. % chcon - change file security context chcon [OPTION]... CONTEXT FILE... chcon [OPTION]... [-u USER] [-r ROLE] [-l RANGE] [-t TYPE] FILE... chcon [OPTION]... --reference=RFILE FILE... Change the SELinux security context of each FILE to CONTEXT. With --reference, change the security con‐ text of each FILE to that of RFILE. Mandatory arguments to long options are mandatory for short options too. --dereference affect the referent of each symbolic link (this is the default), rather than the symbolic link itself % curl - transfer a URL curl [options] [URL...] curl is a tool to transfer data from or to a server, using one of the supported protocols (DICT, FILE, SMTP, SMTPS, TELNET and TFTP). The command is designed to work without user interaction. curl offers a busload of useful tricks like proxy support, user authentication, FTP upload, HTTP post, SSL connections, cookies, file transfer resume, Metalink, and more. As you will see below, the number of features will make your head spin! URL % setkeycodes - load kernel scancode-to-keycode mapping table entries setkeycodes scancode keycode ... The setkeycodes command reads its arguments two at a time, each pair of arguments consisting of a scan‐ code (given in hexadecimal) and a keycode (given in decimal). For each such pair, it tells the kernel keyboard driver to map the specified scancode to the specified keycode. duce scancodes that the kernel does not recognize. THEORY The usual PC keyboard produces a series of scancodes for each key press and key release. (Scancodes are stream of keycodes (key press/release events). (Keycodes are shown by showkey.) Apart from a few scan‐ % tar — manipulate tape archives tar [bundled-flags ⟨args⟩] [⟨file⟩ | ⟨pattern⟩ ...] tar {-c} [options] [files | directories] tar {-r | -u} -f archive-file [options] [files | directories] tar {-t | -x} [options] [patterns] zip, jar, ar, xar, rpm, 7-zip, and ISO 9660 cdrom images and can create tar, pax, cpio, ar, zip, 7-zip, and shar archives. torical implementations. See COMPATIBILITY below for details. The other synopsis forms show the preferred usage. The first option to tar is a mode indicator from the % idnconv - codeset converter for named.conf and zone master files idnconv [options..] [file...] idnconv is a codeset converter for named configuration files and zone master files. idnconv performs codeset conversion specified either by the command-line arguments or by the configuration file, and writes the converted text to stdout. If file name is specified, idnconv converts the contents of the file. Otherwise, idnconv converts stdin. able as a general codeset converter. OPERATION MODES idnconv has two operation modes. % pkcheck - Check whether a process is authorized pkcheck [--version] [--help] pkcheck [--list-temp] pkcheck [--revoke-temp] pkcheck --action-id action {--process { pid | pid,pid-start-time | pid,pid-start-time,uid } | --system-bus-name busname} [--allow-user-interaction] [--enable-internal-agent] [--detail key value...] pkcheck is used to check whether a process, specified by either --process (see below) or --system-bus-name, is authorized for action. The --detail option can be used zero or more times to pass details about action. If --allow-user-interaction is passed, pkcheck blocks while waiting for % ldns-walk - Retrieve the contents of a DNSSEC signed zone ldns-walk [ OPTION ] ZONE ldns-walk is used to retrieve the contents of a DNSSEC signed zone. It does this through NSEC-walking (following the chain of NSEC records) and 'guessing' the next non-existent owner name for each NSEC. can be circumvented by querying the authoritative nameserver directly (with the @ argument). Of course the nameserver that is used must be DNSSEC-aware. % ddns-confgen - ddns key generation tool tsig-keygen [-a algorithm] [-h] [-r randomfile] [name] ddns-confgen [-a algorithm] [-h] [-k keyname] [-q] [-r randomfile] [-s name | -z zone] tsig-keygen and ddns-confgen are invocation methods for a utility that generates keys for use in TSIG signing. The resulting keys can be used, for example, to secure dynamic DNS updates to a zone or for the rndc command channel. When run as tsig-keygen, a domain name can be specified on the command line which will be used as the name of the generated key. If no name is specified, the default is tsig-key. When run as ddns-confgen, the generated key is accompanied by configuration text and instructions that can be used with nsupdate and named when setting up dynamic DNS, including an example update-policy % gio - GIO commandline tool gio version gio cat LOCATION... gio copy [OPTION...] SOURCE... DESTINATION gio info [OPTION...] LOCATION... gio list [OPTION...] [LOCATION...] gio mime MIMETYPE [HANDLER] % dbus-daemon - Message bus daemon dbus-daemon dbus-daemon [--version] [--session] [--system] [--config-file=FILE] [--print-address [=DESCRIPTOR]] [--print-pid [=DESCRIPTOR]] [--fork] dbus-daemon is the D-Bus message bus daemon. See http://www.freedesktop.org/software/dbus/ for more information about the big picture. D-Bus is first a library that provides one-to-one communication between any two applications; dbus-daemon is an application that uses this library to implement a message bus daemon. Multiple programs connect to the message bus daemon and can exchange messages with one another. There are two standard message bus instances: the systemwide message bus (installed on many systems as the "messagebus" init service) and the per-user-login-session message bus (started each time a user logs % thin_check - validate thin provisioning metadata on device or file thin_check [options] {device|file} thin_check checks thin provisioning metadata created by the device-mapper thin provisioning target on a device or file. -q, --quiet Suppress output messages, return only exit code. -h, --help Print help and exit. % jfs_fsck - initiate replay of the JFS transaction log, and check and repair a JFS formatted device jfs_fsck [ -afnpvV ] [ -j journal_device ] [ --omit_journal_replay ] [ --replay_journal_only ] device jfs_fsck is used to replay the JFS transaction log, check a JFS formatted device for errors, and fix any errors found. jfs_fsck must be run as root. WARNING jfs_fsck should only be used to check an unmounted file system or a file system that is mounted READ ONLY. Using jfs_fsck to check a file system mounted other than READ ONLY could seriously damage the file system! % cache_restore - restore cache metadata file to device or file cache_restore [options] -i {device|file} -o {device|file} cache_restore restores cache metadata created by the respective device-mapper target dumped into an XML device or file. If restored to a metadata device , the metadata can be processed by the device-mapper target. -i, --input {device|file} Input file or device with metadata. -o, --output {device|file} % btrfstune - tune various filesystem parameters btrfstune [options] [...] btrfstune can be used to enable, disable or set various filesystem parameters. The filesystem must be unmounted. have kernel support for the features. You can find a complete list of features and kernel version of their introduction at https://btrfs.wiki.kernel.org/index.php/Changelog#By_feature . Also, the manual Some of the features could be enabled on a mounted filesystem. Please refer to the respective section in % script - make typescript of terminal session script [options] [file] script makes a typescript of everything displayed on your terminal. It is useful for students who need a hardcopy record of an interactive session as proof of an assignment, as the typescript file can be If the argument file is given, script saves the dialogue in this file. If no filename is given, the dia‐ logue is saved in the file typescript. -a, --append Append the output to file or to typescript, retaining the prior contents. % btrfs-find-root - filter to find btrfs root btrfs-find-root [options] btrfs-find-root is used to find the satisfied root, you can filter by root tree’s objectid, generation, level. -a Search through all the metadata extents, even the root is already found. -g Filter root tree by it’s original transaction id, tree root’s generation in default. -o % rshd - Remote shell server rshd [OPTION...] Remote shell server. -a, --verify-hostname ask hostname for verification -l, --no-rhosts ignore .rhosts file -L, --log-sessions log successful logins % free - Display amount of free and used memory in the system free [options] free displays the total amount of free and used physical and swap memory in the system, as well as the buffers and caches used by the kernel. The information is gathered by parsing /proc/meminfo. The dis‐ played columns are: total Total installed memory (MemTotal and SwapTotal in /proc/meminfo) used Used memory (calculated as total - free - buffers - cache) free Unused memory (MemFree and SwapFree in /proc/meminfo) shared Memory used (mostly) by tmpfs (Shmem in /proc/meminfo) % tfmtodit - create font files for use with groff -Tdvi tfmtodit [ -sv ] [ -ggf_file ] [ -kskewchar ] tfm_file map_file font tfmtodit creates a font file for use with groff -Tdvi. tfm_file is the name of the TeX font metric file for the font. map_file is a file giving the groff names for characters in the font; this file should consist of a sequence of lines of the form: groff names of the character. If a character has no groff names but exists in the tfm file, then it will be put in the groff font file as an unnamed character. font is the name of the groff font file. The groff font file is written to font. % smartd - SMART Disk Monitoring Daemon smartd [options] other platforms.] smartd is a daemon that monitors the Self-Monitoring, Analysis and Reporting Technology (SMART) system built into most ATA/SATA and SCSI/SAS hard drives and solid-state drives. The purpose of SMART is to monitor the reliability of the hard drive and predict drive failures, and to carry out different types of lier standards (see REFERENCES below). smartd will attempt to enable SMART monitoring on ATA devices (equivalent to smartctl -s on) and polls % lscpu - display information about the CPU architecture lscpu [-a|-b|-c] [-x] [-s directory] [-e[=list]|-p[=list]] lscpu -h|-V lscpu gathers CPU architecture information from sysfs, /proc/cpuinfo and any applicable architecture-spe‐ cific libraries (e.g. librtas on Powerpc). The command output can be optimized for parsing or for easy readability by humans. The information includes, for example, the number of CPUs, threads, cores, sock‐ ets, and Non-Uniform Memory Access (NUMA) nodes. There is also information about the CPU caches and cache sharing, family, model, bogoMIPS, byte order, and stepping. In virtualized environments, the CPU architecture information displayed reflects the configuration of the guest operating system which is typically different from the physical (host) system. On architectures that support retrieving physical topology information, lscpu also displays the number of physical sock‐ ets, chips, cores in the host system. % ldns-mx - print out the mx record(s) for a domain ldns-mx DOMAIN ldns-mx is used to print out mx information of a domain. ldns-mx has no options. Written by the ldns team as an example for ldns usage. REPORTING BUGS Report bugs to . % bash - GNU Bourne-Again SHell bash [options] [command_string | file] Bash is an sh-compatible command language interpreter that executes commands read from the standard input or from a file. Bash also incorporates useful features from the Korn and C shells (ksh and csh). Bash is intended to be a conformant implementation of the Shell and Utilities portion of the IEEE POSIX All of the single-character shell options documented in the description of the set builtin command can % fortune - print a random, hopefully interesting, adage fortune [-acefilosw] [-n length] [ -m pattern] [[n%] file/dir/all] When fortune is run with no arguments it prints out a random epigram. Epigrams are divided into several categories, where each category is sub-divided into those which are potentially offensive and those which are not. Options The options are as follows: -a Choose from all lists of maxims, both offensive and not. (See the -o option for more information on offensive fortunes.) -c Show the cookie file from which the fortune came. % ldns-chaos - give some information about a nameserver ldns-chaos retrieves all the addresses of the nameserver and then queries each address for its ver‐ sion.bind and hostname.bind. ldns-chaos is a bit more complex than ldns-mx. ldns-chaos has no options. Written by the ldns team as an example for ldns usage. % utmpdump - dump UTMP and WTMP files in raw format utmpdump [options] [filename] utmpdump is a simple program to dump UTMP and WTMP files in raw format, so they can be examined. utmp‐ dump reads from stdin unless a filename is passed. -f, --follow Output appended data as the file grows. -o, --output file Write command output to file instead of standard output. -r, --reverse % halt, poweroff, reboot - Halt, power-off or reboot the machine The following options are understood: --help Print a short help text and exit. % dmesg - print or control the kernel ring buffer dmesg [options] dmesg --clear dmesg --read-clear [options] dmesg --console-level level dmesg --console-on dmesg --console-off dmesg is used to examine or control the kernel ring buffer. The default action is to display all messages from the kernel ring buffer. % git-receive-pack - Receive what is pushed into the repository git-receive-pack Invoked by git send-pack and updates the repository with the information fed from the remote end. send-pack side, and the program pair is meant to be used to push updates to remote repository. For pull speaking, it is the local end git-receive-pack runs, but to the user who is sitting at the send-pack end, it is updating the remote. Confused?) There are other real-world examples of using update and post-update hooks found in the % efibootmgr - manipulate the EFI Boot Manager ... ] [ -O ] [ -p PART ] [ -q ] [ -t seconds ] [ -T ] [ -u ] [ -v ] [ -V ] [ -w ] [ -@ file ] efibootmgr is a userspace application used to modify the Intel Extensible Firmware Interface (EFI) Boot running boot option, and more. /sys/firmware/efi/vars or /sys/firmware/efi/efivars/. % link - call the link function to create a link to a file link OPTION --help display this help and exit --version output version information and exit Written by Michael Stone. % external-journal ] [ -E extended_options ] [ -z undo_file ] device use a journal, if the system has been shut down uncleanly without any errors, normally, after replaying the committed transactions in the journal, the file system should be marked as clean. Hence, for indicates that further checking is required. -n option is specified, and -c, -l, or -L options are not specified. However, even if it is safe to do % which - shows the full path of (shell) commands. which [options] [--] programname [...] Which takes one or more arguments. For each of its arguments it prints to stdout the full path of the executables that would have been executed when this argument had been entered at the shell prompt. It does this by searching for an executable or script in the directories listed in the environment variable --all, -a Print all matching executables in PATH, not just the first. % git-shell - Restricted login shell for Git-only SSH access chsh -s $(command -v git-shell) git clone @localhost:/path/to/repo.git ssh @localhost server-side Git commands implementing the pull/push functionality, plus custom commands present in a subdirectory named git-shell-commands in the user’s home directory. git shell accepts the following commands after the -c option: git receive-pack , git upload-pack , git upload-archive Call the corresponding server-side command to support the client’s git push, git fetch, or git % lnstat - unified linux network statistics lnstat [options] lnstat is a generalized and more feature-complete replacement for the old rtstat program. It is commonly used to periodically print a selection of statistical values exported by the kernel. In addition to routing cache statistics, it supports any kind of statistics the linux kernel exports via a file in /proc/net/stat/. Each file in /proc/net/stat/ contains a header line listing the column names. These names are used by lnstat as keys for selecting which statistics to print. For every CPU present in the system, a line fol‐ lows which lists the actual values for each column of the file. lnstat sums these values up (which in fact are counters) before printing them. After each interval, only the difference to the last value is % update-leap - leap-seconds file manager/updater update-leap [-flags] [-flag [value]] [--option-name[[=| ]value]] All arguments must be options. update-leap will validate the file currently on the local system and if necessary, updates leap-second definition file. tion can be specified on the command line. If the file does not exist, is not valid, has expired, or is expiring soon, a new copy will be down‐ loaded. If the new copy validates, it is installed and NTP is (optionally) restarted. % idn [OPTION]... [STRINGS]... Command line interface to the internationalized domain name library. All strings are expected to be encoded in the preferred charset used by your locale. Use `--debug' to find out what this charset is. You can override the charset used by setting environment variable CHARSET. To process a string that starts with `-', for example `-foo', use `--' to signal the end of parameters, as in `idn --quiet -a -- -foo'. % will NOT list all the users in /etc/passwd, shadow, PAM, etc. only those created by SASL (via -f file use file for sasldb % xzdec, lzmadec - Small .xz and .lzma decompressors xzdec [option...] [file...] lzmadec [option...] [file...] xzdec is a liblzma-based decompression-only tool for .xz (and only .xz) files. xzdec is intended to work xz --decompress --stdout (and possibly a few other commonly used options) to decompress .xz files. lzmadec is identical to xzdec except that lzmadec supports .lzma files instead of .xz files. To reduce the size of the executable, xzdec doesn't support multithreading or localization, and doesn't read options from XZ_DEFAULTS and XZ_OPT environment variables. xzdec doesn't support displaying inter‐ process instead of displaying progress information. % hdparm - get/set SATA/IDE device parameters hdparm [options] [device ...] hdparm provides a command line interface to various kernel interfaces supported by the Linux rectly only with the latest kernels. When no options are given, -acdgkmur is assumed. For "Get/set" options, a query without the optional parameter (e.g. -d) will query (get) the device state, and with a parameter (e.g., -d0) will set the device state. % mkreiserfs - The create tool for the Linux ReiserFS filesystem. mkreiserfs [ -dfV ] [ -b | --block-size N ] [ -h | --hash HASH ] [ -u | --uuid UUID ] [ -l | --label LABEL ] [ --format FORMAT ] [ -q | --quiet ] [ -j | --journal-device FILE ] [ -s | --journal-size N ] [ -o | --journal-offset N ] [ -t | --transaction-max-size N ] [ -B | --badblocks file ] device [ filesys‐ tem-size ] mkreiserfs creates a Linux ReiserFS filesystem on a device (usually a disk partition). device is the special file corresponding to a device or to a partition (e.g /dev/hdXX for an IDE disk partition or /dev/sdXX for a SCSI disk partition). filesystem-size is the size in blocks of the filesystem. If omitted, mkreiserfs will automatically set it. % isc-config.sh - Get information about the installed version of ISC BIND isc-config.sh [--cflags] [--exec-prefix] [--libs] [--prefix] [--version] [libraries...] isc-config.sh prints information related to the installed version of ISC BIND, such as the compiler and linker flags required to compile and link programs that use ISC BIND libraries. The optional libraries are used to report specific details for compiling and linking for the listed listed on the command line. (Some libraries require other libraries, so are implied.) --cflags Prints the compiler command line options required to compile files that use ISC BIND. Use the libraries command line argument(s) to print additional specific flags to pass to the C compiler. % ping - send ICMP ECHO_REQUEST to network hosts [-M pmtudisc_option] [-N nodeinfo_option] [-w deadline] [-W timeout] [-p pattern] [-Q tos] [-s packetsize] [-S sndbuf] [-t ttl] [-T timestamp option] [hop]... {destination} ping uses the ICMP protocol's mandatory ECHO_REQUEST datagram to elicit an ICMP ECHO_RESPONSE from a host or gateway. ECHO_REQUEST datagrams (``pings'') have an IP and ICMP header, followed by a struct timeval and then an arbitrary number of ``pad'' bytes used to fill out the packet. -6. % and GNUTLS_SO_PIN. % grops - PostScript driver for groff grops [-glmv] [-b n] [-c n] [-F dir] [-I dir] [-p papersize] [-P prologue] [-w n] [files ...] grops translates the output of GNU troff to PostScript. Normally grops should be invoked by using the groff command with a -Tps option. (Actually, this is the default for groff.) If no files are given, grops reads the standard input. A filename of - also causes grops to read the standard input. Post‐ Script output is written to the standard output. When grops is run by groff options can be passed to grops using groff's -P option. vention) if called with multiple file arguments. To print such concatenated output it is necessary to deactivate DSC handling in the printing program or previewer. See section FONT INSTALLATION below for a guide how to install fonts for grops. % setarch - change reported architecture in new program environment and set personality flags setarch arch [options] [program [argument...]] arch [options] [program [argument...]] setarch --list|-h|-V various personality options. The default program is /bin/sh. --list List the architectures that setarch knows about. Whether setarch can actually set each of these architectures depends on the running kernel. % reiserfsck - The checking tool for the ReiserFS filesystem. reiserfsck [ -aprVy ] [ --rebuild-sb | --check | --fix-fixable | --rebuild-tree | --clean-attributes ] [ -j | --journal device ] [ -z | --adjust-size ] [ -n | --nolog ] [ -B | --badblocks file ] [ -l | --log‐ file file ] [ -q | --quiet ] [ -y | --yes ] [ -f | --force ] [ -S | --scan-whole-partition ] [ --no-jour‐ nal-available ] device Reiserfsck searches for a Reiserfs filesystem on a device, replays any necessary transactions, and either checks or repairs the file system. device is the special file corresponding to a device or to a partition (e.g /dev/hdXX for an IDE disk partition or /dev/sdXX for a SCSI disk partition). --rebuild-sb % autoreconf - Update generated configuration files autoreconf [OPTION]... [DIRECTORY]... Run `autoconf' (and `autoheader', `aclocal', `automake', `autopoint' (formerly `gettextize'), and `libtoolize' where appropriate) repeatedly to remake the GNU Build System files in specified DIRECTORIES and their subdirectories (defaulting to `.'). By default, it only remakes those files that are older than their sources. If you install new versions of the GNU Build System, you can make `autoreconf' remake all of the files by giving it the `--force' option. Operation modes: -h, --help print this help, then exit % crond - daemon to execute scheduled commands crond [-c | -h | -i | -n | -p | -P | -s | -m] crond -x [ext,sch,proc,pars,load,misc,test,bit] systemd is enabled, then unit file is installed into /lib/systemd/system/crond.service and daemon is started by systemctl start crond.service command. It returns immediately, thus, there is no need to need to start it with the '&' parameter. Cron searches /var/spool/cron for crontab files which are named after accounts in /etc/passwd; The found crontabs are loaded into the memory. Cron also searches for /etc/anacrontab and any files in the and checks each job to see if it needs to be run in the current minute. When executing commands, any output is mailed to the owner of the crontab (or to the user specified in the MAILTO environment variable % rmdir - remove empty directories rmdir [OPTION]... DIRECTORY... Remove the DIRECTORY(ies), if they are empty. --ignore-fail-on-non-empty ignore each failure that is solely because a directory is non-empty -p, --parents remove DIRECTORY and its ancestors; e.g., 'rmdir -p a/b/c' is similar to 'rmdir a/b/c a/b a' % addftinfo - add information to troff font files for use with groff addftinfo [ -v ] [ param-option value.... ] res unitwidth font addftinfo reads a troff font file and adds some additional font-metric information that is used by the groff system. The font file with the information added is written on the standard output. The informa‐ tion added is guessed using some parametric information about the font and assumptions about the tradi‐ tional troff names for characters. The main information added is the heights and depths of characters. The res and unitwidth arguments should be the same as the corresponding parameters in the DESC file; font is the name of the file describing the font; if font ends with I the font will be assumed to be italic. –v prints the version number. All other options change one of the parameters that are used to derive the heights and depths. Like the % write - send a message to another user write user [ttyname] write allows you to communicate with other users, by copying lines from your terminal to theirs. When you run the write command, the user you are writing to gets a message of the form: Message from yourname@yourhost on yourtty at hh:mm ... Any further lines you enter will be copied to the specified user's terminal. If the other user wants to reply, they must run write as well. When you are done, type an end-of-file or interrupt character. The other user will see the message EOF indicating that the conversation is over. % msgexec - process translations of message catalog reads a translation from standard input. It is invoked once for each translation. Its output becomes msgexec's output. msgexec's return code is the maximum return code across all invocations. A special builtin command called '0' outputs the translation, followed by a null byte. The output of "msgexec 0" is suitable as input for "xargs -0". Command input: --newline add newline at the end of input % code. The tool has originally been developed as a second implementation for Libgcrypt to allow comparing against the primary implementation and to be used for internal consistency checks. It should not be used for sensitive data because no mechanisms to clear the stack etc are used. The code has been written in a highly portable manner and requires only a few standard definitions to be provided in a config.h file. % [-b bfdname|--target=bfdname] [-C|--demangle[=style]] [-e filename|--exe=filename] [-f|--functions] [-s|--basename] [-i|--inlines] [-p|--pretty-print] [-j|--section=name] [-H|--help] [-V|--version] [addr addr ...] offset in a section of a relocatable object, it uses the debugging information to figure out which file % systemd-ask-password - Query the user for a system password message specified on the command line. When run from a TTY it will query a password on the TTY and print it to standard output. When run with no TTY or with --no-tty it will query the password system-wide and allow active users to respond via several agents. The latter is only available to privileged processes. The purpose of this tool is to query system-wide passwords — that is passwords not attached to a specific user account. Examples include: unlocking encrypted hard disks when they are plugged in or at boot, entering an SSL certificate passphrase for web and VPN servers. Existing agents are: % pkg-config - Return metainformation about installed libraries [--short-errors] [--silence-errors] [--errors-to-stdout] [--debug] [--cflags] [--libs] [--libs-only-L] provides] [--print-requires] [--print-requires-private] [LIBRARIES...] The pkg-config program is used to retrieve information about installed libraries in the system. It is typically used to compile and link against one or more libraries. Here is a typical usage scenario in a Makefile: program: program.c cc program.c $(pkg-config --cflags --libs gnomeui) % pwconv, pwunconv, grpconv, grpunconv - convert to and from shadow passwords and groups pwconv [options] pwunconv [options] grpconv [options] grpunconv [options] The pwconv command creates shadow from passwd and an optionally existing shadow. The pwunconv command creates passwd from passwd and shadow and then removes shadow. The grpconv command creates gshadow from group and an optionally existing gshadow. % pacman-key - manage pacman's list of trusted keys pacman-key [options] operation [targets] pacman-key is a wrapper script for GnuPG used to manage pacman’s keyring, which is the collection of PGP keys used to check signed packages and databases. It provides the ability to import and export keys, fetch keys from keyservers and update the key trust database. More complex keyring management can be achieved using GnuPG directly combined with the --homedir option pointing at the pacman keyring (located in /etc/pacman.d/gnupg by default). Invoking pacman-key consists of supplying an operation with any potential options and targets to operate OPERATIONS % umount - unmount file systems umount -a [-dflnrv] [-t fstype] [-O option...] umount [-dflnrv] {directory|device}... umount -h|-V The umount command detaches the mentioned file system(s) from the file hierarchy. A file system is spec‐ ified by giving the directory where it has been mounted. Giving the special device on which the file on more than one directory. it, or when some process has its working directory there, or when a swap file on it is in use. The % pam_tally - The login counter (tallying) module pam_tally.so [file=/path/to/counter] [onerr=[fail|succeed]] [magic_root] [even_deny_root_account] [deny=n] [lock_time=n] [unlock_time=n] [per_user] [no_lock_time] [no_reset] [audit] [silent] [no_log_info] pam_tally [--file /path/to/counter] [--user username] [--reset[=n]] [--quiet] many attempts fail. deprecated and will be removed in a future release. pam_tally comes in two parts: pam_tally.so and pam_tally. The former is the PAM module and the latter, a % psfaddtable - add a Unicode character table to a console font psfaddtable fontfile tablefile outfile psfaddtable takes a console font in .psf format given by fontfile and merges it with the Unicode charac‐ ter table given by tablefile to produce a font file with an embedded character table, which is written to outfile. An input file name of "-" denotes standard input, and an output file name of "-" denotes stan‐ dard output. If the fontfile already contains an embedded character table, it is ignored. TABLE FILE FORMAT Each line in the tablefile should be either blank, contain a comment (preceded by #), or contain a sequence of numbers in either decimal (default), octal (preceded by 0), or hexadecimal (preceded by 0x) format, separated by spaces or tabs. The first number on each line indicates the glyph slot in the font % fstrim - discard unused blocks on a mounted filesystem fstrim [-a] [-o offset] [-l length] [-m minimum-size] [-v] mountpoint fstrim is used on a mounted filesystem to discard (or "trim") blocks which are not in use by the filesys‐ behavior based on range or size, as explained below. The mountpoint argument is the pathname of the directory where the filesystem is mounted. Running fstrim frequently, or even using mount -o discard, might negatively affect the lifetime of poor- quality SSD devices. For most desktop and server systems a sufficient trimming frequency is once a week. % rm - remove files or directories rm [OPTION]... [FILE]... not remove directories. If the -I or --interactive=once option is given, and there are more than three files or the -r, -R, or --recursive are given, then rm prompts the user for whether to proceed with the entire operation. If the response is not affirmative, the entire command is aborted. Otherwise, if a file is unwritable, standard input is a terminal, and the -f or --force option is not given, or the -i or --interactive=always option is given, rm prompts the user for whether to remove the file. If the response is not affirmative, the file is skipped. % ddns-confgen - ddns key generation tool tsig-keygen [-a algorithm] [-h] [-r randomfile] [name] ddns-confgen [-a algorithm] [-h] [-k keyname] [-q] [-r randomfile] [-s name | -z zone] tsig-keygen and ddns-confgen are invocation methods for a utility that generates keys for use in TSIG signing. The resulting keys can be used, for example, to secure dynamic DNS updates to a zone or for the rndc command channel. When run as tsig-keygen, a domain name can be specified on the command line which will be used as the name of the generated key. If no name is specified, the default is tsig-key. When run as ddns-confgen, the generated key is accompanied by configuration text and instructions that can be used with nsupdate and named when setting up dynamic DNS, including an example update-policy % mklost+found - create a lost+found directory on a mounted Linux second extended file system mklost+found mklost+found is used to create a lost+found directory in the current working directory on a Linux second extended file system. There is normally a lost+found directory in the root directory of each filesystem. recover a filesystem, it does not need to allocate blocks in the filesystem to store a large number of recovery. There are none. % efivar - Tool to manipulate UEFI variables efivar [OPTION...] -L, --list-guids list guids efivar knows about -l, --list list current variables -p, --print print variable specified by --name -n, --name= % pr - convert text files for printing pr [OPTION]... [FILE]... Paginate or columnate FILE(s) for printing. With no FILE, or when FILE is -, read standard input. Mandatory arguments to long options are mandatory for short options too. +FIRST_PAGE[:LAST_PAGE], --pages=FIRST_PAGE[:LAST_PAGE] begin [stop] printing with page FIRST_[LAST_]PAGE -COLUMN, --columns=COLUMN output COLUMN columns and print columns down, unless -a is used. Balance number of lines in the % netctl - Control the netctl network profile manager netctl [--help | --version] manager. The following commands are understood: list List all available profiles. Active profiles will be marked with a ‘*’. % vgmknodes — recreate volume group directory and logical volume special files ones and removes unused ones. --refresh manually without a clustered lock manager. % killall - kill processes by name killall [-Z, --context pattern] [-e, --exact] [-g, --process-group] [-i, --interactive] [-o, --older-than TIME] [-q, --quiet] [-r, --regexp] [-s, --signal SIGNAL, -SIGNAL] [-u, --user user] [-v, --verbose] killall -l killall -V, --version killall sends a signal to all processes running any of the specified commands. If no signal name is specified, SIGTERM is sent. If the command name is not regular expression (option -r) and contains a slash (/), processes executing that particular file will be selected for killing, independent of their name. % ebrowse - create a class hierarchy database ebrowse [options] [FILES...] format. ebrowse is used to create the database used by the class browser in Emacs. The program follows the usual GNU command line syntax, with long options starting with two dashes ("-"). -a, --append append output to existing file % prlimit - get and set process resource limits prlimit [options] [--resource[=limits] [--pid PID] prlimit [options] [--resource[=limits] command [argument...] Given a process id and one or more resources, prlimit tries to retrieve and/or modify the limits. When command is given, prlimit will run this command with the given arguments. The limits parameter is composed of a soft and a hard value, separated by a colon (:), in order to modify the existing values. If no limits are given, prlimit will display the current values. If one of the values is not given, then the existing one will be used. To specify the unlimited or infinity limit % zsoelim - satisfy .so requests in roff input zsoelim [-CVh] [file ...] zsoelim parses file arguments, or if none are specified, its standard input for lines of the form: .so These requests are replaced by the contents of the filename specified. If the request cannot be met, ported depending upon compile time options. If the request can be met by a compressed file, this file is decompressed using an appropriate decompressor and its output is used to satisfy the request. Traditionally, soelim programs were used to allow roff preprocessors to be able to preprocess the files % [lock_time=n] [unlock_time=n] [root_unlock_time=n] [serialize] [audit] [silent] [no_log_info] [debug] many attempts fail. manipulate the counter file. It can display user counts, set individual counts, or clear all counts. % etags, ctags - generate tag file for Emacs, vi etags [-aCDGIQRVh] [-i file] [-l language] [-o tagfile] [-r regexp] [--parse-stdin=file] [--append] [--no-defines] [--globals] [--no-globals] [--no-line-directive] [--include=file] [--ignore-indentation] [--language=language] [--members] [--no-members] [--output=tagfile] [--class-qualify] [--regex=regexp] [--no-regex] [--help] [--version] file ... ctags [-aCdgIQRVh] [-BtTuvwx] [-l language] [-o tagfile] [-r regexp] [--parse-stdin=file] [--append] [--backward-search] [--cxref] [--no-defines] [--globals] [--no-globals] [--no-line-directive] [--ignore-indentation] [--language=language] [--members] [--no-members] [--class-qualify] [--output=tagfile] [--regex=regexp] [--update] [--help] [--version] file ... % Compare three files line by line. Mandatory arguments to long options are mandatory for short options too. -A, --show-all output all changes, bracketing conflicts -e, --ed output ed script incorporating changes from OLDFILE to YOURFILE into MYFILE -E, --show-overlap % iconvconfig - create iconv module configuration cache iconvconfig [options] [directory]... tion file is used to determine the needed modules for a conversion. Loading and parsing such a configu‐ The iconvconfig program reads iconv module configuration files and writes a fast-loading gconv module configuration cache file. In addition to the system provided gconv modules, the user can specify custom gconv module directories with the environment variable GCONV_PATH. However, iconv module configuration caching is used only when the environment variable GCONV_PATH is not set. % msginit - initialize a message catalog msginit [OPTION] Creates a new PO file, initializing the meta information with values from the user's environment. Mandatory arguments to long options are mandatory for short options too. Input file location: -i, --input=INPUTFILE input POT file If no input file is given, the current directory is searched for the POT file. If it is -, standard input is read. % autoconf - Generate configuration scripts autoconf [OPTION]... [TEMPLATE-FILE] Generate a configuration script from a TEMPLATE-FILE if given, or `configure.ac' if present, or else `configure.in'. Output is sent to the standard output if TEMPLATE-FILE is given, else into `configure'. Operation modes: -h, --help print this help, then exit -V, --version print version number, then exit -v, --verbose % update-ca-trust - manage consolidated and dynamic configuration of CA certificates and associated trust Authority (CA) certificates and associated trust. The feature is available for new applications that read the consolidated configuration files found in the Parts of the new feature are also provided in a way to make it useful for legacy applications. Many legacy applications expect CA certificates and trust configuration in a fixed location, contained in % resizepart - tell the kernel about the new size of a partition resizepart device partition length resizepart tells the Linux kernel about the new size of the specified partition. The command is a simple wrapper around the "resize partition" ioctl. PARAMETERS device The disk device. partition The partition number. % unix_chkpwd [...] unix_chkpwd is a helper program for the pam_unix module that verifies the password of the current user. It also checks password and account expiration dates in shadow. It is not intended to be run directly from the command line and logs a security violation if done so. It is typically installed setuid root or setgid shadow. The interface of the helper - command line options, and input/output data format are internal to the pam_unix module and it should not be called directly from applications. % getfacl - get file access control lists getfacl [-aceEsRLPtpndvh] file ... getfacl [-aceEsRLPtpndvh] - For each file, getfacl displays the file name, owner, the group, and the Access Control List (ACL). If a directory has a default ACL, getfacl also displays the default ACL. Non-directories cannot have default ACLs. If getfacl is used on a file system that does not support ACLs, getfacl displays the access permissions defined by the traditional file mode permission bits. The output format of getfacl is as follows: % vimtutor - the Vim tutor vimtutor [-g] [language] Vimtutor starts the Vim tutor. It copies the tutor file first, so that it can be modified without chang‐ ing the original file. The Vimtutor is useful for people that want to learn their first Vim commands. The optional argument -g starts vimtutor with gvim rather than vim, if the GUI version of vim is avail‐ able, or falls back to Vim if gvim is not found. The optional [language] argument is the two-letter name of a language, like "it" or "es". If the [lan‐ guage] argument is missing, the language of the current locale will be used. If a tutor in this language is available, it will be used. Otherwise the English version will be used. % partx - tell the kernel about the presence and numbering of on-disk partitions partx [-a|-d|-P|-r|-s|-u] [-t type] [-n M:N] [-] disk partx [-a|-d|-P|-r|-s|-u] [-t type] partition [disk] Given a device or disk-image, partx tries to parse the partition table and list its contents. It can also tell the kernel to add or remove partitions from its bookkeeping. The disk argument is optional when a partition argument is provided. To force scanning a partition as if it were a whole disk (for example to list nested subpartitions), use the argument "-" (hyphen-minus). For example: % glib-compile-schemas - GSettings schema compiler glib-compile-schemas [OPTION...] {DIRECTORY} glib-compile-schemas compiles all the GSettings XML schema files in DIRECTORY into a binary file with the name gschemas.compiled that can be used by GSettings. The XML schema files must have the filename extension .gschema.xml. For a detailed description of the XML file format, see the GSettings documentation. specified in the XDG_DATA_DIRS environment variable. The usual location to install schema files is In addition to schema files, glib-compile-schemas reads 'vendor override' files, which are key files that can override default values for keys in the schemas. The group names in the key files are the schema id, % nl-qdisc-{add|list|delete} - Manage queueing disciplines The nl-qdisc tools allow to manage and configure queueing disciplines (qdiscs) in the kernel. -h or --help Print help text to console and exit. -v or --version % top - display Linux processes top -hv|-bcHiOSs -d secs -n max -u|U user -p pid -o fld -w [cols] The traditional switches `-' and whitespace are optional. The top program provides a dynamic real-time view of a running system. It can display system summary information as well as a list of processes or threads currently being managed by the Linux kernel. The types of system summary information shown and the types, order and size of information displayed for pro‐ cesses are all user configurable and that configuration can be made persistent across restarts. The program provides a limited interactive interface for process manipulation as well as a much more extensive interface for personal configuration -- encompassing every aspect of its operation. And while top is referred to throughout this document, you are free to name the program anything you wish. That new name, possibly an alias, will then be reflected on top's display and used when reading and writ‐ % systemd-nspawn - Spawn a namespace container for debugging, testing and building as the process tree, the various IPC subsystems and the host and domain name. --directory= command line option. By using the --machine= option an OS tree is automatically searched for in a couple of locations, most importantly in /var/lib/machines, the suggested directory to place container images installed on the system. % readlink - print resolved symbolic links or canonical file names readlink [OPTION]... FILE... Print value of a symbolic link or canonical file name -f, --canonicalize canonicalize by following every symlink in every component of the given name recursively; all but the last component must exist -e, --canonicalize-existing canonicalize by following every symlink in every component of the given name recursively, all com‐ ponents must exist -m, --canonicalize-missing % insmod - Simple program to insert a module into the Linux Kernel insmod [filename] [module options...] instead, which is more clever and can handle module dependencies. Only the most general of error messages are reported: as the work of trying to link the module is now done inside the kernel, the dmesg usually gives more information about errors. others. % bashbug - report a bug in bash bashbug [--version] [--help] [email-address] bashbug is a shell script to help the user compose and mail bug reports concerning bash in a standard format. bashbug invokes the editor specified by the environment variable EDITOR on a temporary copy of the bug report format outline. The user must fill in the appropriate fields and exit the editor. bashbug then mails the completed report to bug-bash@gnu.org, or email-address. If the report cannot be mailed, it is saved in the file dead.bashbug in the invoking user's home directory. The bug report format outline consists of several sections. The first section provides information about the machine, operating system, the bash version, and the compilation environment. The second section should be filled in with a description of the bug. The third section should be a description of how to reproduce the bug. The optional fourth section is for a proposed fix. Fixes are encouraged. % comm - compare two sorted files line by line % xargs - build and execute command lines from standard input xargs [-0prtx] [-E eof-str] [-e[eof-str]] [--eof[=eof-str]] [--null] [-d delimiter] [--delimiter delimiter] [-I replace-str] [-i[replace-str]] [--replace[=replace-str]] [-l[max-lines]] [-L max-lines] [--max-lines[=max-lines]] [-n max-args] [--max-args=max-args] [-s max-chars] [--max-chars=max-chars] [-P max-procs] [--max-procs=max-procs] [--process-slot-var=name] [--interactive] [--verbose] [--exit] [--no-run-if-empty] [--arg-file=file] [--show-limits] [--version] [--help] [command [initial-arguments]] ed by blanks (which can be protected with double or single quotes or a backslash) or newlines, and exe‐ cutes the command (default is /bin/echo) one or more times with any initial-arguments followed by items read from standard input. Blank lines on the standard input are ignored. The command line for command is built up until it reaches a system-defined limit (unless the -n and -L options are used). The specified command will be invoked as many times as necessary to use up the list % blkdeactivate — utility to deactivate block devices blkdeactivate [-d dm_options] [-e] [-h] [-l lvm_options] [-m mpath_options] [-u] [-v] [device] blkdeactivate utility deactivates block devices. If a device is mounted, the utility can unmount it auto‐ matically before trying to deactivate. The utility currently supports device-mapper devices (DM), includ‐ -d, --dmoption dm_options % usb-devices - print USB device details usb-devices usb-devices is a (bash) shell script that can be used to display details of USB buses in the system and the devices connected to them. The output of the script is similar to the usb/devices file available either under /proc/bus (if usbfs is mounted), or under /sys/kernel/debug (if debugfs is mounted there). The script is primarily intended to be used if the file is not available. In contrast to the usb/devices file, this script only lists active interfaces (those marked with a "*" in the usb/devices file) and their endpoints. Be advised that there can be differences in the way information is sorted, as well as in the format of % systemd-tty-ask-password-agent - List or process pending systemd password requests systemd-tty-ask-password-agent is a password agent that handles password requests of the system, for example for hard disk encryption passwords or SSL certificate passwords that need to be queried at boot-time or during runtime. The following options are understood: --list Lists all currently pending system password requests. % tail - output the last part of files tail [OPTION]... [FILE]... header giving the file name. With no FILE, or when FILE is -, read standard input. Mandatory arguments to long options are mandatory for short options too. -c, --bytes=[+]NUM output the last NUM bytes; or use -c +NUM to output starting with byte NUM of each file -f, --follow[={name|descriptor}] % dmstats — device-mapper statistics management dmsetup stats command [options] dmstats command [device_name |--uuid uuid|--major major --minor minor] dmstats clear device_name [--allprograms|--programid id] [--allregions|--regionid id] dmstats create [device_name... |file_path...] [--alldevices] [--areas nr_areas|--areasize area_size] [--bounds histogram_boundaries] [--filemap] [--nogroup] [--precise] [--start start_sector --length length|--segments] [--userdata user_data] [--programid id] dmstats delete [device_name] [--alldevices] [--allprograms|--programid id] [--allregions|--regionid id] dmstats group [device_name] [--alias name] [--alldevices] [--regions regions] dmstats help [-c|-C|--columns] dmstats list [device_name] [--histogram] [--allprograms|--programid id] [--units units] [--area] [--region] [--group] [--nosuffix] [--notimesuffix] [-v|--verbose[-v|--verbose]] dmstats print [device_name] [--clear] [--allprograms|--programid id] [--allregions|--regionid id] dmstats report [device_name] [--interval seconds] [--count count] [--units units] [--histogram] % systemd-cgls - Recursively show control group contents systemd-cgls recursively shows the contents of the selected Linux control group hierarchy in a tree. If arguments are specified, shows all member processes of the specified control groups plus all their assumed in the systemd control group hierarchy. If no argument is specified and the current working directory is beneath the control group mount point /sys/fs/cgroup, shows the contents of the control group the working directory refers to. Otherwise, the full systemd control group hierarchy is shown. By default, empty control groups are not shown. The following options are understood: % groupdel - delete a group groupdel [options] GROUP The groupdel command modifies the system account files, deleting all entries that refer to GROUP. The named group must exist. The options which apply to the groupdel command are: -h, --help Display help message and exit. -R, --root CHROOT_DIR Apply changes in the CHROOT_DIR directory and use the configuration files from the CHROOT_DIR % tftpd - Trivial File Transfer Protocol server tftpd {directory} requested via TFTP protocol, effectively chrooting tftpd to this directory. File names are validated not It is in difference of variants of tftpd usually distributed with unix-like systems, which take a list of directories and match file names to start from one of given prefixes or to some random default, when no arguments were given. There are two reasons not to behave in this way: first, it is inconvenient, clients are not expected to know something about layout of filesystem on server host. And second, TFTP protocol % git-upload-pack - Send objects packed back to git-fetch-pack git-upload-pack [--[no-]strict] [--timeout=] [--stateless-rpc] [--advertise-refs] Invoked by 'git fetch-pack', learns what objects the other side is missing, and sends them after packing. The UI for the protocol is on the 'git fetch-pack' side, and the program pair is meant to be used to pull updates from a remote repository. For push operations, see 'git send-pack'. % shuf - generate random permutations shuf [OPTION]... [FILE] shuf -e [OPTION]... [ARG]... shuf -i LO-HI [OPTION]... Write a random permutation of the input lines to standard output. With no FILE, or when FILE is -, read standard input. Mandatory arguments to long options are mandatory for short options too. -e, --echo treat each ARG as an input line % lsattr - list file attributes on a Linux second extended file system lsattr [ -RVadlpv ] [ files... ] the attributes and what they mean. -R Recursively list attributes of directories and their contents. -V Display the program version. -a List all files in directories, including files that start with `.'. -d List directories like other files, rather than listing their contents. % thin_delta - Print the differences in the mappings between two thin devices. thin_delta [options] {device|file} thin_delta allows you to compare the mappings in two thin volumes (snapshots allow common blocks between thin volumes). The numeric identifier for the first thin volume to diff. The numeric identifier for the second thin volume to diff. % test - check file types and compare values test EXPRESSION test [ EXPRESSION ] [ ] [ OPTION Exit with the status determined by EXPRESSION. --help display this help and exit --version output version information and exit % The options -v and --version print the version information of the program to standard output and exit. The options -h and --help print a usage information of the program to standard output and stop the pro‐ gram instantly. All other options are assumed to be groffer options. They are internally passed to groffer. They over‐ ride the behavior of the program. The options are optional, they can be omitted. The filespec arguments correspond to the filespec arguments of groffer. So they are either the names of % resolvconf — a framework for managing multiple DNS configurations resolvconf -I resolvconf [-m metric] [-p] [-x] -a interface[.protocol] ] [] [--] [...] graph, showing information related to each commit, and the files in the trees of each revision. To control which revisions to show, gitk supports most options applicable to the git rev-list command. It also supports a few options applicable to the git diff-* commands to control how the changes each commit introduces are shown. Finally, it supports some gitk-specific options. gitk generally only understands options with arguments in the sticked form (see gitcli(7)) due to limitations in the command-line parser. % device. label. % fsck.minix - check consistency of Minix filesystem fsck.minix [options] device fsck.minix performs a consistency check for the Linux MINIX filesystem. The program assumes the filesystem is quiescent. fsck.minix should not be used on a mounted device unless you can be sure nobody is writing to it. Remember that the kernel can write to device when it searches for files. The device name will usually have the following form: % lslogins - display information about known users in the system lslogins [options] [-s|-u[=UID]] [-g groups] [-l logins] Examine the wtmp and btmp logs, /etc/shadow (if necessary) and /etc/passwd and output the desired data. The default action is to list info about all the users in the system. Mandatory arguments to long options are mandatory for short options too. -a, --acc-expiration for more info). (Requires root privileges.) % w - Show who is logged on and what they are doing. w [options] user [...] w displays information about the users currently on the machine, and their processes. The header shows, in this order, the current time, how long the system has been running, how many users are currently The following entries are displayed for each user: login name, the tty name, the remote host, login time, idle time, JCPU, PCPU, and the command line of their current process. The JCPU time is the time used by all processes attached to the tty. It does not include past background jobs, but does include currently running background jobs. The PCPU time is the time used by the current process, named in the "what" field. % compile_et - error table compiler compile_et file Compile_et converts a table listing error-code names and associated messages into a C source file suit‐ The source file name must end with a suffix of ``.et''; the file consists of a declaration supplying the name (up to four characters long) of the error-code table: error_table name error_code name, " string " % gzip, gunzip, zcat - compress or expand files gunzip [ -acfhklLnNrtvV ] [-S suffix] [ name ... ] zcat [ -fhLV ] [ name ... ] Gzip reduces the size of the named files using Lempel-Ziv coding (LZ77). Whenever possible, each file is replaced by one with the extension .gz, while keeping the same ownership modes, access and modification files are specified, or if a file name is "-", the standard input is compressed to the standard output. Gzip will only attempt to compress regular files. In particular, it will ignore symbolic links. If the compressed file name is too long for its file system, gzip truncates it. Gzip attempts to trun‐ name consists of small parts only, the longest parts are truncated. For example, if file names are lim‐ % attr - extended attributes on XFS filesystem objects attr [ -LRSq ] -s attrname [ -V attrvalue ] pathname attr [ -LRSq ] -g attrname pathname attr [ -LRSq ] -r attrname pathname attr [ -LRSq ] -l pathname Extended attributes implement the ability for a user to attach name:value pairs to objects within the XFS filesystem. name. It is thus aimed specifically at users of the XFS filesystem - for filesystem independent extended % genl-ctrl-list - List available kernel-side Generic Netlink families genl-ctrl-list [-d] Queries the Generic Netlink controller in kernel and prints a list of all registered Generic Netlink fam‐ ilies including the version of the interface that has been registered. -h or --help Print help text to console and exit. -v or --version Print versioning information to console and exit. -d or --details % ldns-test-edns - test if dns cache supports EDNS and DNSSEC. ldns-test-edns [ -i ] { ip } ldns-test-edns tests a DNS cache and checks if it supports EDNS0 and DNSSEC types so that it can be used as a dnssec-enabled DNS cache. It sends two queries to the cache, one for the root key and one for a DS record. These must succeed, the answer must have EDNS, that type and signatures. If the IP address is good for DNSSEC, it is printed with 'OK'. Otherwise short description is given of the failure. If OK is given, the cache should be good to use as a cache for a local configured DNSSEC validator. The tool assumes the root is signed and Sweden is signed. Also, the queries are sent with the CD flag, the tool does not check that the results are validated, but that they can be validated. % ldns-update - send a dynamic update packet ldns-update [ zone ] ip [ tsig_name tsig_als tsig_hmac ] ldns-update is used to send a dynamic update packet. zone Use this zone instead of trying to read it from the zonefile's SOA record. ip Send the update to this IP address tsig_name tsig_alg tsig_hmac % kprop [-r realm] [-f file] [-d] [-P port] [-s keytab] slave_host -r realm Specifies the realm of the master server. -f file Specifies the filename where the dumped principal database file is to be found; by default the % zmore - file perusal filter for crt viewing of compressed text zmore [ name ... ] Zmore is a filter which allows examination of compressed or plain text files one screenful at a time on a soft-copy terminal. zmore works on files compressed with compress, pack or gzip, and also on uncom‐ pressed files. If a file does not exist, zmore looks for a file of the same name with the addition of a .gz, .z or .Z suffix. Zmore normally pauses after each screenful, printing --More-- at the bottom of the screen. If the user then types a carriage return, one more line is displayed. If the user hits a space, another screenful is displayed. Other possibilities are enumerated later. Zmore looks in the file /etc/termcap to determine terminal characteristics, and to determine the default % aclocal [OPTION]... --automake-acdir=DIR --system-acdir=DIR directory holding third-party system-wide files % thin_rmap - output reverse map of a thin provisioned region of blocks from metadata device or file thin_rmap [options] {device|file} thin_rmap outputs the reverse mapping stored in the metadata on a device or file between a region of thin provisioned pool blocks and the associated thin provisioned devices. --region output reverse map -h, --help Print help and exit. % msgunfmt - uncompile message catalog from binary format msgunfmt [OPTION] [FILE]... Convert binary message catalog to Uniforum style .po file. Mandatory arguments to long options are mandatory for short options too. Operation mode: -j, --java Java mode: input is a Java ResourceBundle class --csharp C# mode: input is a .NET .dll file % external-journal ] [ -E extended_options ] [ -z undo_file ] device use a journal, if the system has been shut down uncleanly without any errors, normally, after replaying the committed transactions in the journal, the file system should be marked as clean. Hence, for indicates that further checking is required. -n option is specified, and -c, -l, or -L options are not specified. However, even if it is safe to do % tsort - perform topological sort tsort [OPTION] [FILE] Write totally ordered list consistent with the partial ordering in FILE. With no FILE, or when FILE is -, read standard input. --help display this help and exit --version output version information and exit Written by Mark Kettenis. % gpgsm - CMS encryption and signing tool gpgsm [--homedir dir] [--options file] [options] command [args] and the CMS protocol. It is mainly used as a backend for S/MIME mail processing. gpgsm includes a full featured certificate management and complies with all rules defined for the German Sphinx project. Commands are not distinguished from options except for the fact that only one command is allowed. Commands not specific to the function --version % fsadm — utility to resize or check filesystem on a device fsadm [options] check device fsadm [options] resize device [new_size] -e|--ext-offline -f|--force Bypass some sanity checks. % pgrep, pkill - look up or signal processes based on name and other attributes pgrep [options] pattern pkill [options] pattern pgrep looks through the currently running processes and lists the process IDs which match the selection criteria to stdout. All the criteria have to match. For example, $ pgrep -u root sshd will only list the processes called sshd AND owned by root. On the other hand, $ pgrep -u root,daemon will list the processes owned by root OR daemon. % Process macros in FILEs. If no FILE or if FILE is `-', standard input is read. Mandatory or optional arguments to long options are mandatory or optional for short options too. Operation modes: --help display this help and exit --version output version information and exit -E, --fatal-warnings % xzcmp, xzdiff, lzcmp, lzdiff - compare compressed files from which the compression format suffix has been stripped. If two files are specified, then they are served. The names lzcmp and lzdiff are provided for backward compatibility with LZMA Utils. % msgfmt - compile message catalog to binary format msgfmt [OPTION] filename.po ... Generate binary message catalog from textual translation description. Mandatory arguments to long options are mandatory for short options too. Similarly for optional argu‐ ments. Input file location: filename.po ... input files -D, --directory=DIRECTORY add DIRECTORY to list for input files search % nscd - name service cache daemon Nscd is a daemon that provides a cache for the most common name service requests. The default configura‐ There are two caches for each database: a positive one for items found, and a negative one for items not --help will give you a list with all options and what they do. % xzless, lzless - view xz or lzma compressed (text) files xzless [file...] lzless [file...] xzless is a filter that displays text from compressed files to a terminal. It works on files compressed The command named lzless is provided for backward compatibility with LZMA Utils. ENVIRONMENT % and improves the file access speed. mount point of it and reduces fragmentation of all files in this mount point. -c Get a current fragmentation count and an ideal fragmentation count, and calculate fragmentation % factor - factor numbers factor [NUMBER]... factor OPTION Print the prime factors of each specified integer NUMBER. If none are specified on the command line, read them from standard input. --help display this help and exit --version output version information and exit Written by Paul Rubin, Torbjorn Granlund, and Niels Moller. % strfile - create a random access file for storing strings unstr - dump strings in pointer order strfile [-iorsx] [-c char] sourcefile [outputfile] unstr [-c char] datafile[.ext] [outputfile] strfile reads a file containing groups of lines separated by a line containing a single percent `%' sign (or other specified delimiter character) and creates a data file which contains a header structure and a The output file, if not specified on the command line, is named sourcefile.dat. The purpose of unstr is to undo the work of strfile. It prints out the strings contained in the source‐ file, which is datafile.ext without its extension, or datafile if no extension is specified (in this % rtcwake - enter a system sleep state until specified wakeup time rtcwake [options] [-d device] [-m standby_mode] {-s seconds|-t time_t} specified time. It uses any RTC framework driver that supports standard driver model wakeup flags. disk). Not all systems have persistent media that are appropriate for such suspend modes. % grog — guess options for a following groff command grog [-C] [--run] [--warnings] [--ligatures] [ groff-option ....] [--] [ filespec ....] grog -h | --help grog -v | --version to perform the input with the groff program. The corresponding groff command is usually displayed in standard output. With the option --run, the generated line is output into standard error and the generated groff command is run on the standard output. The option -v or --version prints information on the version number. Also -h or --help prints usage % blocks-per-group ] [ -G number-of-groups ] [ -i bytes-per-inode ] [ -I inode-size ] [ -j ] [ -J journal- options ] [ -N number-of-inodes ] [ -n ] [ -m reserved-blocks-percentage ] [ -o creator-os ] [ -O [^]fea‐ ture[,...] ] [ -q ] [ -r fs-revision-level ] [ -E extended-options ] [ -v ] [ -F ] [ -L volume-label ] [ -M last-mounted-directory ] [ -S ] [ -t fs-type ] [ -T usage-type ] [ -U UUID ] [ -V ] [ -e errors-behav‐ ior ] [ -z undo_file ] device [ fs-size ] size ] by device. % nl - number lines of files nl [OPTION]... [FILE]... Write each FILE to standard output, with line numbers added. With no FILE, or when FILE is -, read standard input. Mandatory arguments to long options are mandatory for short options too. -b, --body-numbering=STYLE use STYLE for numbering body lines -d, --section-delimiter=CC use CC for separating logical pages % git-cvsserver - A CVS server emulator for Git SSH: export CVS_SERVER="git cvsserver" cvs -d :ext:user@server/path/repo.git co pserver (/etc/inetd.conf): cvspserver stream tcp nowait nobody /usr/bin/git-cvsserver git-cvsserver pserver git-cvsserver [options] [pserver|server] [ ...] % ocsptool - GnuTLS OCSP tool ocsptool [-flags] [-flag [value]] [--option-name[[=| ]value]] All arguments must be options. Ocsptool is a program that can parse and print information about OCSP requests/responses, generate requests and verify responses. -d number, --debug=number constrained to being: in the range 0 through 9999 % grub-macbless - bless a mac file/directory Mac-style bless on HFS or HFS+ -p, --ppc bless for ppc-based macs -v, --verbose print verbose messages. % iptables-restore — Restore IP Tables ip6tables-restore — Restore IPv6 Tables iptables-restore [-chntv] [-M modprobe] [-T name] [file] ip6tables-restore [-chntv] [-M modprobe] [-T name] [file] iptables-restore and ip6tables-restore are used to restore IP and IPv6 Tables from data specified on STDIN or in file. Use I/O redirection provided by your shell to read from a file or specify file as an argument. -c, --counters restore the values of all packet and byte counters % tbl - format tables for troff tbl [-Cv] [files ...] tbl compiles descriptions of tables embedded within troff input files into commands that are understood by troff. Normally, it should be invoked using the -t option of groff. It is highly compatible with Unix tbl. The output generated by GNU tbl cannot be processed with Unix troff; it must be processed with GNU troff. If no files are given on the command line or a filename of - is given, the standard input is read. -C Enable compatibility mode to recognize .TS and .TE even when followed by a character other than space or newline. Leader characters (\a) are handled as interpreted. % networkctl - Query the status of network links configuration syntax. The following options are understood: -a --all Show all links with status. -h, --help % gtester-report - test report formatting utility gtester-report [option...] [gtester-log] gtester-report is a script which converts the XML output generated by gtester into HTML. -h, --help print help and exit -v, --version print version information and exit -s, --subunit Output subunit. Needs python-subunit. % bzcat - decompresses files to stdout bzcat [ -s ] [ filenames ... ] coding. Compression is generally considerably better than that achieved by more conventional The command-line options are deliberately very similar to those of GNU gzip, but they are not identical. % watchgnupg - Read and print logs from a socket watchgnupg [--force] [--verbose] socketname Most of the main utilities are able to write their log files to a Unix Domain socket if configured that way. watchgnupg is a simple listener for such a socket. It ameliorates the output with a time stamp and available for Windows. watchgnupg is commonly invoked as watchgnupg --force ~/.gnupg/S.log watchgnupg understands these options: % sudo, sudoedit — execute a command as another user sudo -h | -K | -k | -V sudo -v [-AknS] [-a type] [-g group] [-h host] [-p prompt] [-u user] sudo -l [-AknS] [-a type] [-g group] [-h host] [-p prompt] [-U user] [-u user] [command] sudo [-AbEHnPS] [-a type] [-C num] [-c class] [-g group] [-h host] [-p prompt] [-r role] [-t type] [-u user] [VAR=value] [-i | -s] [command] sudoedit [-AknS] [-a type] [-C num] [-c class] [-g group] [-h host] [-p prompt] [-u user] file ... sudo allows a permitted user to execute a command as the superuser or another user, as specified by the security policy. The invoking user's real (not effective) user ID is used to determine the user name with which to query the security policy. sudo supports a plugin architecture for security policies and input/output logging. Third parties can develop and distribute their own policy and I/O logging plugins to work seamlessly with the sudo front end. % vercmp - version comparison utility vercmp is used to determine the relationship between two given version numbers. It outputs values as follows: Version comparison operates as follows: % xxd - make a hexdump or do the reverse. xxd -h[elp] xxd [options] [infile [outfile]] xxd -r[evert] [options] [infile [outfile]] xxd creates a hex dump of a given file or standard input. It can also convert a hex dump back to its `mail-safe' ASCII representation, but has the advantage of decoding to standard output. Moreover, it can be used to perform binary file patching. If no infile is given, standard input is read. If infile is specified as a `-' character, then input is taken from standard input. If no outfile is given (or a `-' character is in its place), results are sent to standard output. % tailf - follow the growth of a log file tailf [option] file days it's safe to use tail -f (from coreutils), in contrast to what the original documentation below says. updating the access time for the file, so a filesystem flush does not occur periodically when no log activity is happening. tailf is extremely useful for monitoring log files on a laptop when logging is infrequent and the user wishes the hard disk to spin down to conserve battery life. % fallocate - preallocate or deallocate space to a file fallocate [-c|-p|-z] [-o offset] -l length [-n] filename fallocate -d [-o offset] [-l length] filename fallocate is used to manipulate the allocated disk space for a file, either to deallocate or preallocate it. For filesystems which support the fallocate system call, preallocation is done quickly by allocating creating a file by filling it with zeroes. % colcrt - filter nroff output for CRT previewing colcrt [options] [file...] colcrt provides virtual half-line and reverse line feed sequences for terminals without such capability, and on which overstriking is destructive. Half-line characters and underlining (changed to dashing `-') are placed on new lines in between the normal output lines. -, --no-underlining Causes all half-lines to be printed, effectively double spacing the output. Normally, a minimal % halt, poweroff, reboot - Halt, power-off or reboot the machine The following options are understood: --help Print a short help text and exit. % mkfs.bfs - make an SCO bfs filesystem mkfs.bfs [options] device [block-count] mkfs.bfs creates an SCO bfs filesystem on a block device (usually a disk partition or a file accessed via the loop device). The block-count parameter is the desired size of the filesystem, in blocks. If nothing is specified, the entire partition will be used. -N, --inodes number % vipw, vigr - edit the password or group file vipw [options] vigr [options] vipw edits the password file after setting the appropriate locks, and does any necessary processing after the password file is unlocked. If the password file is already locked for editing by another user, vipw file in the same manner as vipw does the passwd file. ENVIRONMENT If the following environment variable exists, it will be utilized by vipw and vigr: % gapplication - D-Bus application launcher gapplication version gapplication list-apps gapplication launch APPID gapplication launch APPID [FILE...] gapplication list-actions APPID gapplication action APPID ACTION [PARAMETER] % gettext - translate message gettext [OPTION] [[TEXTDOMAIN] MSGID] gettext [OPTION] -s [MSGID]... The gettext program translates a natural language message into the user's language, by looking up the translation in a message catalog. Display native language translation of a textual message. -d, --domain=TEXTDOMAIN retrieve translated messages from TEXTDOMAIN -e enable expansion of some escape sequences % veritysetup - manage dm-verity (block level verification) volumes veritysetup Veritysetup is used to configure dm-verity managed device-mapper mappings. Device-mapper verity target provides read-only transparent integrity checking of block devices using ker‐ nel crypto API. The dm-verity devices are always read-only. Veritysetup supports these operations: format % btrfs-map-logical - map btrfs logical extent to physical extent btrfs-map-logical btrfs-map-logical can be used to find out what the physical offsets are on the mirrors, the result is dumped into stdout in default. Mainly used for debug purpose. -l|--logical Logical extent to map. -c|--copy % diff - compare files line by line diff [OPTION]... FILES Compare FILES line by line. Mandatory arguments to long options are mandatory for short options too. --normal output a normal diff (the default) -q, --brief report only when files differ -s, --report-identical-files % psktool - GnuTLS PSK tool psktool [-flags] [-flag [value]] [--option-name[[=| ]value]] All arguments must be options. Program that generates random keys for use with TLS-PSK. The keys are stored in hexadecimal format in a key file. -d number, --debug=number constrained to being: in the range 0 through 9999 % AS - the portable GNU assembler. as [-a[cdghlns][=file]] [--alternate] [-D] [--compress-debug-sections] [--nocompress-debug-sections] [--debug-prefix-map old=new] [--defsym sym=val] [-f] [-g] [--gstabs] [--help] [-I dir] [-J] [-K] [-L] [--listing-lhs-width=NUM] [--listing-cont-lines=NUM] [--keep-locals] [--no-pad-sections] [-o objfile] [-R] [--hash-size=NUM] [--reduce-memory-overheads] [--statistics] [-v] [-version] [--version] % mkfs.minix - make a Minix filesystem mkfs.minix [options] device [size-in-blocks] mkfs.minix creates a Linux MINIX filesystem on a device (usually a disk partition). The device is usually of the following form: on a character device :-). % id - print real and effective user and group IDs id [OPTION]... [USER] Print user and group information for the specified USER, or (when USER omitted) for the current user. -a ignore, for compatibility with other versions -Z, --context print only the security context of the process -g, --group print only the effective group ID -G, --groups % xmlwf - Determines if an XML document is well-formed xmlwf [-s] [-n] [-p] [-x] [-e encoding] [-w] [-d output-dir] [-c] [-m] [-r] [-t] [-v] [file ...] xmlwf uses the Expat library to determine if an XML document is well-formed. It is non-validating. If you do not specify any files on the command-line, and you have a recent version of xmlwf, the input file will be read from standard input. A well-formed document must adhere to the following rules: xmlwf does not currently check for a valid XML declaration. % wipefs - wipe a signature from a device wipefs [-ahnpqtV] [-o offset] device... wipefs can erase filesystem, raid or partition-table signatures (magic strings) from the specified device to make the signatures invisible for libblkid. wipefs does not erase the filesystem itself nor any other data from the device. When used without any options, wipefs lists all visible filesystems and the offsets of their basic signatures. wipefs calls the BLKRRPART ioctl when it has erased a partition-table signature to inform the kernel about the change. command lists only the first offset where a magic string has been detected. The device is not scanned % Wget - The non-interactive network downloader. wget [option]... [URL]... GNU Wget is a free utility for non-interactive download of files from the Web. It supports HTTP, HTTPS, and FTP protocols, as well as retrieval through HTTP proxies. Wget is non-interactive, meaning that it can work in the background, while the user is not logged on. contrast, most of the Web browsers require constant user's presence, which can be a great hindrance when transferring a lot of data. Wget can follow links in HTML, XHTML, and CSS pages, to create local versions of remote web sites, fully downloading." While doing that, Wget respects the Robot Exclusion Standard (/robots.txt). Wget can be % vgs — report information about volume groups [-d|--debug] [-h|-?|--help] [--ignorelockingfailure] [--ignoreskippedcluster] [--logonly] [--namepre‐ fixes] [--noheadings] [--nosuffix] [-P|--partial] [--reportformat {basic|json}] [--rows] [--separator Separator] [--unbuffered] [--units hHbBsSkKmMgGtTpPeE] [--unquoted] [-v|--verbose] [--version] [Vol‐ vgs produces formatted output about volume groups. --all List all volume groups. Equivalent to not specifying any volume groups. % hwclock - read or set the hardware clock (RTC) hwclock [function] [option...] hwclock is a tool for accessing the Hardware Clock. It can: display the Hardware Clock time; set the Hardware Clock to a specified time; set the Hardware Clock from the System Clock; set the System Clock from the Hardware Clock; compensate for Hardware Clock drift; correct the System Clock timescale; set the kernel's timezone, NTP timescale, and epoch (Alpha only); compare the System and Hardware Clocks; and predict future Hardware Clock values based on its drift rate. option --update-drift was added. See their respective descriptions below. FUNCTIONS The following functions are mutually exclusive, only one can be given at a time. If none is given, the % xfs_rtcp - XFS realtime copy command xfs_rtcp [ -e extsize ] [ -p ] source ... target xfs_rtcp -V xfs_rtcp copies a file to the realtime partition on an XFS filesystem. If there is more than one source and target, the final argument (the target) must be a directory which already exists. -e extsize Sets the extent size of the destination realtime file. -p Use if the size of the source file is not an even multiple of the block size of the destination filesystem. When -p is specified xfs_rtcp will pad the destination file to a size which is an even % iptables [-t table] {-A|-C|-D} chain rule-specification ip6tables [-t table] {-A|-C|-D} chain rule-specification iptables [-t table] -I chain [rulenum] rule-specification iptables [-t table] -R chain rulenum rule-specification iptables [-t table] -D chain rulenum iptables [-t table] -S [chain [rulenum]] iptables [-t table] {-F|-L|-Z} [chain [rulenum]] [options...] % texindex - sort Texinfo index files texindex [OPTION]... FILE... Generate a sorted index for each TeX output FILE. Usually FILE... is specified as `foo.??' for a docu‐ ment `foo.texi'. -h, --help display this help and exit --version display version information and exit -- end option processing % xfs_mkfile - create an XFS file xfs_mkfile [ -v ] [ -n ] [ -p ] size[k|b|m|g] filename ... xfs_mkfile -V xfs_mkfile creates one or more files. The file is padded with zeroes by default. The default size is in bytes, but it can be flagged as kilobytes, blocks, megabytes, or gigabytes with the k, b, m, or g suf‐ fixes, respectively. -v Verbose. Report the names and sizes of created files. -n No bytes. Create a holey file - that is, do not write out any data, just seek to end of file and write a block. % autopoint - copies standard gettext infrastructure autopoint [OPTION]... Copies standard gettext infrastructure files into a source package. --help print this help and exit --version print version information and exit -f, --force force overwriting of files that already exist % kbd_mode - report or set the keyboard mode kbd_mode [ -a | -u | -k | -s ] [ -C CONSOLE ] Without argument, kbd_mode prints the current keyboard mode (RAW, MEDIUMRAW or XLATE). With argument, it sets the keyboard mode as indicated: -s: scancode mode (RAW), -k: keycode mode (MEDIUMRAW), -a: ASCII mode (XLATE), % pam_timestamp_check - Check to see if the default timestamp is valid pam_timestamp_check [-k] [-d] [target_user] With no arguments pam_timestamp_check will check to see if the default timestamp is valid, or optionally remove it. -k -d Instead of returning validity using an exit status, loop indefinitely, polling regularly and printing the status on standard output. % chroot - run command or interactive shell with special root directory chroot OPTION --groups=G_LIST --userspec=USER:GROUP specify user and group (ID or name) to use --skip-chdir do not change working directory to '/' % lsns - list namespaces lsns [options] [namespace] lsns lists information about all the currently accessible namespaces or about the given namespace. The namespace identifier is an inode number. The default output is subject to change. So whenever possible, you should avoid using default outputs in your scripts. Always explicitly define expected columns by using the --output option together with a columns list in environments where a stable output is required. (see unshare --mount-proc for more details). lsns is not able to see persistent namespaces without pro‐ % lvmsadc — LVM system activity data collector lvmsadc % lzmainfo - show information stored in the .lzma file header lzmainfo [--help] [--version] [file...] fied file, decodes the header, and prints it to standard output in human readable format. If no files are given or file is -, standard input is read. Usually the most interesting information is the uncompressed size and the dictionary size. Uncompressed size can be shown only if the file is in the non-streamed .lzma format variant. The amount of memory required to decompress the file is a few dozen kilobytes plus the dictionary size. lzmainfo is included in XZ Utils primarily for backward compatibility with LZMA Utils. % lnstat - unified linux network statistics lnstat [options] lnstat is a generalized and more feature-complete replacement for the old rtstat program. It is commonly used to periodically print a selection of statistical values exported by the kernel. In addition to routing cache statistics, it supports any kind of statistics the linux kernel exports via a file in /proc/net/stat/. Each file in /proc/net/stat/ contains a header line listing the column names. These names are used by lnstat as keys for selecting which statistics to print. For every CPU present in the system, a line fol‐ lows which lists the actual values for each column of the file. lnstat sums these values up (which in fact are counters) before printing them. After each interval, only the difference to the last value is % envsubst - substitutes environment variables in shell format strings envsubst [OPTION] [SHELL-FORMAT] Substitutes the values of environment variables. Operation mode: -v, --variables output the variables occurring in SHELL-FORMAT Informative output: -h, --help display this help and exit -V, --version % iconv - convert text from one character encoding to another iconv [options] [-f from-encoding] [-t to-encoding] [inputfile]... The iconv program reads in text in one encoding and outputs the text in another encoding. If no input files are given, or if it is given as a dash (-), iconv reads from standard input. If no output file is given, iconv writes to standard output. If no from-encoding is given, the default is derived from the current locale's character encoding. If no to-encoding is given, the default is derived from the current locale's character encoding. -f from-encoding, --from-code=from-encoding Use from-encoding for input characters. % kpropd [-r realm] [-A admin_server] [-a acl_file] [-f slave_dumpfile] [-F principal_database] [-p program. If incremental propagation is enabled, it periodically requests incremental updates from the master KDC. When the slave receives a kprop request from the master, kpropd accepts the dumped KDC database and database to the slave servers. Upon a successful download of the KDC database file, the slave Kerberos server will have an up-to-date KDC database. % pgrep, pkill - look up or signal processes based on name and other attributes pgrep [options] pattern pkill [options] pattern pgrep looks through the currently running processes and lists the process IDs which match the selection criteria to stdout. All the criteria have to match. For example, $ pgrep -u root sshd will only list the processes called sshd AND owned by root. On the other hand, $ pgrep -u root,daemon will list the processes owned by root OR daemon. % fold - wrap each input line to fit in specified width fold [OPTION]... [FILE]... Wrap input lines in each FILE, writing to standard output. With no FILE, or when FILE is -, read standard input. Mandatory arguments to long options are mandatory for short options too. -b, --bytes count bytes rather than columns -s, --spaces break at spaces % chrt - manipulate the real-time attributes of a process chrt [options] priority command [argument...] chrt [options] -p [priority] pid chrt sets or retrieves the real-time scheduling attributes of an existing pid, or runs command with the given attributes. POLICIES -o, --other -f, --fifo Set scheduling policy to SCHED_FIFO. % sync - Synchronize cached writes to persistent storage sync [OPTION] [FILE]... Synchronize cached writes to persistent storage If one or more files are specified, sync only them, or their containing file systems. -d, --data sync only file data, no unneeded metadata -f, --file-system sync the file systems that contain the files --help display this help and exit % lvconvert — change LV type and other utilities lvconvert [OPTION]... VolumeGroup/LogicalVolume -b, --background --cachepolicy Policy --cachesettings Key=Value -c, --chunksize ChunkSize[b|B|s|S|k|K|m|M|g|G] --corelog --discards {ignore|nopassdown|passdown} -i, --interval Seconds --merge --mirrorlog {disk|core|mirrored} -m, --mirrors Number % dpa - DNS Packet Analyzer. Analyze DNS packets in ip trace files dpa [ OPTION ] TRACEFILE uniques (i.e. count all different occurences). -c expressionlist Count occurrences of matching expressions -f expression Filter: only process packets that match the expression -h Show usage % unlink - call the unlink function to remove the specified file unlink FILE unlink OPTION Call the unlink function to remove the specified FILE. --help display this help and exit --version output version information and exit Written by Michael Stone. % ss - another utility to investigate sockets ss [options] [ FILTER ] ss is used to dump socket statistics. It allows showing information similar to netstat. It can display more TCP and state informations than other tools. established connection. -h, --help Show summary of options. -V, --version % split - split a file into pieces split [OPTION]... [FILE [PREFIX]] With no FILE, or when FILE is -, read standard input. Mandatory arguments to long options are mandatory for short options too. -a, --suffix-length=N --additional-suffix=SUFFIX append an additional SUFFIX to file names % dconf - Simple tool for manipulating a dconf database dconf read KEY dconf list DIR dconf write KEY VALUE dconf reset [-f] PATH dconf compile OUTPUT KEYFILEDIR dconf update dconf watch PATH % iptables-restore — Restore IP Tables ip6tables-restore — Restore IPv6 Tables iptables-restore [-chntv] [-M modprobe] [-T name] [file] ip6tables-restore [-chntv] [-M modprobe] [-T name] [file] iptables-restore and ip6tables-restore are used to restore IP and IPv6 Tables from data specified on STDIN or in file. Use I/O redirection provided by your shell to read from a file or specify file as an argument. -c, --counters restore the values of all packet and byte counters % tset, reset - terminal initialization tset [-IQVcqrsw] [-] [-e ch] [-i ch] [-k ch] [-m mapping] [terminal] reset [-IQVcqrsw] [-] [-e ch] [-i ch] [-k ch] [-m mapping] [terminal] mination is done as follows, using the first terminal type found. ting TERM according to the type passed to it by /etc/inittab.) % getent [option]... database key... are configured in /etc/nsswitch.conf. If one or more key arguments are provided, then only the entries that match the supplied keys will be displayed. Otherwise, if no key is provided, all entries will be displayed (unless the database does not support enumeration). enumerating each socket address structure returned. % rndc - name server control utility rndc [-b source-address] [-c config-file] [-k key-file] [-s server] [-p port] [-q] [-r] [-V] [-y key_id] {command} rndc controls the operation of a name server. It supersedes the ndc utility that was provided in old BIND releases. If rndc is invoked with no command line options or arguments, it prints a short summary of the supported commands and the available options and their arguments. rndc communicates with the name server over a TCP connection, sending commands authenticated with digital signatures. In the current versions of rndc and named, the only supported authentication algorithms are command request and the name server's response. All commands sent over the channel must be signed by a key_id known to the server. % arping - send ARP REQUEST to a neighbour host arping [-AbDfhqUV] [-c count] [-w deadline] [-s source] {-I interface} {destination} Ping destination on device interface by ARP packets, using source address source. -A The same as -U, but ARP REPLY packets used instead of ARP REQUEST. -b Send only MAC level broadcasts. Normally arping starts from sending broadcast, and switch to uni‐ cast after reply received. Stop after sending count ARP REQUEST timeout expires. % gobject-query - display a tree of types gobject-query froots [OPTION...] gobject-query tree [OPTION...] gobject-query is a small utility that draws a tree of types. gobject-query takes a mandatory argument that specifies whether it should iterate over the fundamental types or print a type tree. froots iterate over fundamental roots % dbus-cleanup-sockets - clean up leftover sockets in a directory dbus-cleanup-sockets [DIRECTORY] The dbus-cleanup-sockets command cleans up unused D-Bus connection sockets. See http://www.freedesktop.org/software/dbus/ for more information about the big picture. If given no arguments, dbus-cleanup-sockets cleans up sockets in the standard default socket directory for the per-user-login-session message bus; this is usually /tmp. Optionally, you can pass a different directory on the command line. On Linux, this program is essentially useless, because D-Bus defaults to using "abstract sockets" that exist only in memory and don't have a corresponding file in /tmp. % lvrename — rename a logical volume [-v|--verbose] [--version] [-f|--force] [--noudevsync] [--reportformat {basic|json}] {OldLogicalVol‐ lvrename renames an existing logical volume or an existing historical logical volume from OldLogicalVol‐ --noudevsync Disable udev synchronisation. The process will not wait for notification from udev. It will con‐ tinue irrespective of any possible udev processing in the background. You should only use this if % msgattrib - attribute matching and manipulation on message catalog msgattrib [OPTION] [INPUTFILE] Filters the messages of a translation catalog according to their attributes, and manipulates the attributes. Mandatory arguments to long options are mandatory for short options too. Input file location: INPUTFILE input PO file -D, --directory=DIRECTORY add DIRECTORY to list for input files search % isc-hmac-fixup - fixes HMAC keys generated by older versions of BIND isc-hmac-fixup {algorithm} {secret} Versions of BIND 9 up to and including BIND 9.6 had a bug causing HMAC-SHA* TSIG keys which were longer incompatible with other DNS implementations. versions of BIND, when using long keys. isc-hmac-fixup modifies those keys to restore compatibility. To modify a key, run isc-hmac-fixup and specify the key's algorithm and secret on the command line. If % rcp - Remote copy rcp [OPTION...] SOURCE DEST rcp [OPTION...] SOURCE... DIRECTORY rcp [OPTION...] --target-directory=DIRECTORY SOURCE... Remote copy SOURCE to DEST, or multiple SOURCE(s) to DIRECTORY. -6, --ipv6 use only IPv6 -d, --target-directory[=DIRECTORY] % sed - stream editor for filtering and transforming text sed [OPTION]... {script-only-if-no-other-script} [input-file]... Sed is a stream editor. A stream editor is used to perform basic text transformations on an input stream (a file or input from a pipeline). While in some ways similar to an editor which permits scripted edits (such as ed), sed works by making only one pass over the input(s), and is consequently more efficient. But it is sed's ability to filter text in a pipeline which particularly distinguishes it from other types of editors. -n, --quiet, --silent suppress automatic printing of pattern space -e script, --expression=script % run-parts - run scripts or programs in a directory run-parts [--test] [--verbose] [--report] [--lsbsysinit] [--regex=RE] [--umask=umask] [--arg=argument] [--exit-on-error] [--help] [--version] [--list] [--reverse] [--] DIRECTORY run-parts -V run-parts runs all the executable files named within constraints described below, found in directory directory. Other files and directories are silently ignored. If neither the --lsbsysinit option nor the --regex option is given then the names must consist entirely If the --lsbsysinit option is given, then the names must not end in .dpkg-old or .dpkg-dist or .dpkg-new or .dpkg-tmp, and must belong to one or more of the following namespaces: the LANANA-assigned namespace % ssh — OpenSSH SSH client (remote login program) [-l login_name] [-m mac_spec] [-O ctl_cmd] [-o option] [-p port] [-Q query_option] [-R address] [-S ctl_path] [-W host:port] [-w local_tun[:remote_tun]] [user@]hostname [command] ssh (SSH client) is a program for logging into a remote machine and for executing commands on a remote machine. It is intended to provide secure encrypted communications between two untrusted hosts over an the secure channel. ssh connects and logs into the specified hostname (with optional user name). The user must prove his/her identity to the remote machine using one of several methods (see below). % flex - the fast lexical analyser generator Generates programs that perform pattern-matching on text. Table Compression: -Ca, --align trade off larger tables for better memory alignment -Ce, --ecs construct equivalence classes -Cf do not compress tables; use -f representation % trust - Tool for operating on the trust policy store trust list trust extract --filter= --format= /path/to/destination trust anchor /path/to/certificate.crt trust is a command line tool to examine and modify the shared trust policy store. See the various sub commands below. The following global options can be used: -v, --verbose Run in verbose mode with debug output. % preconv - convert encoding of input files to something GNU troff understands preconv [-dr] [-e encoding] [files ...] preconv -h | --help preconv -v | --version It is possible to have whitespace between the -e command line option and its parameter. standard output. Currently, this means ASCII characters and ‘\[uXXXX]’ entities, where ‘XXXX’ is a hexa‐ decimal number with four to six digits, representing a Unicode input code. Normally, preconv should be invoked with the -k and -K options of groff. -d Emit debugging messages to standard error (mainly the used encoding). % dircolors - color setup for ls dircolors [OPTION]... [FILE] Output commands to set the LS_COLORS environment variable. Determine format of output: -b, --sh, --bourne-shell output Bourne shell code to set LS_COLORS -c, --csh, --c-shell output C shell code to set LS_COLORS -p, --print-database output defaults % thin_dump - dump thin provisioning metadata from device or file to standard output thin_dump [options] {device|file} thin_dump dumps binary thin provisioning metadata (optionally from alternate block; see option --meta‐ data-snap) created by the device-mapper thin provisioning target on a device or file to standard output for analysis or postprocessing in either XML or human readable format. XML formated metadata can be fed device-mapper target) or file. -f, --format {xml|human_readable} Print output in XML or human readable format. % iptables-save — dump iptables rules to stdout ip6tables-save — dump iptables rules to stdout iptables-save [-M modprobe] [-c] [-t table] ip6tables-save [-M modprobe] [-c] [-t table] iptables-save and ip6tables-save are used to dump the contents of IP or IPv6 Table in easily parseable format to STDOUT. Use I/O-redirection provided by your shell to write to a file. -M, --modprobe modprobe_program Specify the path to the modprobe program. By default, iptables-save will inspect /proc/sys/ker‐ nel/modprobe to determine the executable's path. % thin_repair - repair thin provisioning binary metadata from device/file to device/file thin_repair [options] -i {device|file} -o {device|file} thin_repair reads binary thin provisioning metadata created by the respective device-mapper target from one device or file , repairs it and writes it to another device or file. If written to a metadata device , the metadata can be processed by the device-mapper target. -i, --input {device|file} Input file or device with binary metadata. -o, --output {device|file} Output file or device for repaired binary metadata. If a file is used then it must be preallo‐ % msgcat - combines several message catalogs msgcat [OPTION] [INPUTFILE]... Concatenates and merges the specified PO files. Find messages which are common to two or more of the extracted comments, and file positions will be cumulated, except that if --use-first is specified, they will be taken from the first PO file to define them. Mandatory arguments to long options are mandatory for short options too. Input file location: INPUTFILE ... % whatis - display one-line manual page descriptions whatis [-dlv?V] [-r|-w] [-s list] [-m system[,...]] [-M path] [-L locale] [-C file] name ... Each manual page has a short description available within it. whatis searches the manual page names and displays the manual page descriptions of any name matched. sary to quote the name or escape (\) the special characters to stop the shell from interpreting them. index databases are used during the search, and are updated by the mandb program. Depending on your pages have been installed. To produce an old style text whatis database from the relative index data‐ base, issue the command: % dnssec-importkey - import DNSKEY records from external systems so they can be managed dnssec-importkey [-K directory] [-L ttl] [-P date/offset] [-P sync date/offset] [-D date/offset] [-D sync date/offset] [-h] [-v level] [-V] {keyfile} dnssec-importkey {-f filename} [-K directory] [-L ttl] [-P date/offset] [-P sync date/offset] [-D date/offset] [-D sync date/offset] [-h] [-v level] [-V] [dnsname] dnssec-importkey reads a public DNSKEY record and generates a pair of .key/.private files. The DNSKEY .private files will be generated. The newly-created .private file does not contain private key data, and cannot be used for signing. However, having a .private file makes it possible to set publication (-P) and deletion (-D) times for the % logname - print user's login name logname [OPTION] Print the name of the current user. --help display this help and exit --version output version information and exit Written by FIXME: unknown. REPORTING BUGS % cat - concatenate files and print on the standard output cat [OPTION]... [FILE]... Concatenate FILE(s) to standard output. With no FILE, or when FILE is -, read standard input. -A, --show-all equivalent to -vET -b, --number-nonblank number nonempty output lines, overrides -n -e equivalent to -vE % openvt - start a program on a new virtual terminal (VT). openvt will find the first available VT, and run on it the given command with the given command options, standard input, output and error are directed to that terminal. The current search path ($PATH) is used to find the requested command. If no command is specified then the environment variable $SHELL is used. -c, --console=VTNUMBER plied VT for this to work; -f, --force Force opening a VT without checking whether it is already in use; % msgmerge - merge message catalog and template msgmerge [OPTION] def.po ref.pot Merges two Uniforum style .po files together. The def.po file is an existing PO file with translations which will be taken over to the newly created file as long as they still match; comments will be pre‐ served, but extracted comments and file positions will be discarded. The ref.pot file is the last cre‐ ated PO file with up-to-date source references but old translations, or a PO Template file (generally created by xgettext); any translations or comments in the file will be discarded, however dot comments and file positions will be preserved. Where an exact match cannot be found, fuzzy matching is used to produce better results. Mandatory arguments to long options are mandatory for short options too. Input file location: % grep, egrep, fgrep - print lines matching a pattern grep searches the named input FILEs for lines containing a match to the given PATTERN. If no files are specified, or if the file “-” is given, grep searches standard input. By default, grep prints the matching lines. In addition, the variant programs egrep and fgrep are the same as grep -E and grep -F, respectively. These variants are deprecated, but are provided for backward compatibility. Generic Program Information --help Output a usage message and exit. % tc - show / manipulate traffic control settings dle qdisc-id ] qdisc [ qdisc specific parameters ] qdisc [ qdisc specific parameters ] protocol prio priority filtertype [ filtertype specific parameters ] flowid flow-id % systemd-inhibit - Execute a program with an inhibition lock taken lock will be acquired before the specified command line is executed and released afterwards. being recorded, or similar operations that should not be interrupted. % thin_trim - Issue discard requests for free pool space (offline tool). thin_trim [options] {device|file} thin_trim sends discard requests to the pool device for unprovisioned areas. --pool-inactive Indicates you are aware the pool should be inactive. Suppresses a warning message and prompt. -h, --help Print help and exit. % Run each Texinfo or (La)TeX FILE through TeX in turn until all cross-references are resolved, building all indices. The directory containing each FILE is searched for included files. The suffix of FILE is used to determine its language ((La)TeX or Texinfo). To process (e)plain TeX files, set the environment variable LATEX=tex. General options: -b, --batch % users - print the user names of users currently logged in to the current host users [OPTION]... [FILE] Output who is currently logged in according to FILE. If FILE is not specified, use /var/run/utmp. /var/log/wtmp as FILE is common. --help display this help and exit --version output version information and exit Written by Joseph Arceneaux and David MacKenzie. % nsenter - run program with namespaces of other processes nsenter [options] [program [arguments]] Enters the namespaces of one or more other processes and then executes the specified program. Enterable namespaces are: mount namespace Mounting and unmounting filesystems will not affect the rest of the system (CLONE_NEWNS flag), except for filesystems which are explicitly marked as shared (with mount --make-shared; see /proc /self/mountinfo for the shared flag). UTS namespace Setting hostname or domainname will not affect the rest of the system. (CLONE_NEWUTS flag) % tion to check how many free blocks are present as contiguous and aligned free space. The percentage of contiguous free blocks of size and of alignment chunk_kb is reported. It also displays the minimum/maxi‐ tion can be used to gauge the level of free space fragmentation in the filesystem. -c chunk_kb available in units of kilobytes (Kb). The chunk size must be a power of two and be larger than % bzcat - decompresses files to stdout bzcat [ -s ] [ filenames ... ] coding. Compression is generally considerably better than that achieved by more conventional The command-line options are deliberately very similar to those of GNU gzip, but they are not identical. % cache_repair - repair cache binary metadata from device/file to device/file cache_repair [options] -i {device|file} -o {device|file} cache_repair reads binary cache metadata created by the respective device-mapper target from one device or file , repairs it and writes it to another device or file. If written to a metadata device , the metadata can be processed by the device-mapper target. -i, --input {device|file} Input file or device with binary metadata. -o, --output {device|file} Output file or device for repaired binary metadata. If a file is used then it must be preallo‐ % GNU Parted - a partition manipulation program parted [options] [device [command [options...]...]] parted is a program to manipulate disk partitions. It supports multiple partition table formats, includ‐ ing MS-DOS and GPT. It is useful for creating space for new operating systems, reorganising disk usage, and copying data to new hard disks. Info format. -h, --help displays a help message % dig - DNS lookup utility dig [@server] [-b address] [-c class] [-f filename] [-k filename] [-m] [-p port#] [-q name] [-t type] dig [-h] dig [global-queryopt...] [query...] dig (domain information groper) is a flexible tool for interrogating DNS name servers. It performs DNS lookups and displays the answers that are returned from the name server(s) that were queried. Most DNS administrators use dig to troubleshoot DNS problems because of its flexibility, ease of use and clarity of output. Other lookup tools tend to have less functionality than dig. Although dig is normally used with command-line arguments, it also has a batch mode of operation for % dmsetup — low level logical volume management dmsetup clear device_name dmsetup create device_name [-u|--uuid uuid] [--addnodeoncreate|--addnodeonresume] [-n|--notable|--table {table|table_file}] [--readahead {[+]sectors|auto|none}] dmsetup deps [-o options] [device_name] dmsetup help [-c|-C|--columns] dmsetup info [device_name] dmsetup info -c|-C|--columns [--count count] [--interval seconds] [--nameprefixes] [--noheadings] [-o fields] [-O|--sort sort_fields] [--separator separator] [device_name] dmsetup load device_name [--table {table|table_file}] dmsetup ls [--target target_type] [--exec command] [--tree] [-o options] dmsetup mangle [device_name] dmsetup message device_name sector message dmsetup mknodes [device_name] dmsetup reload device_name [--table {table|table_file}] % mv - move (rename) files mv [OPTION]... [-T] SOURCE DEST mv [OPTION]... SOURCE... DIRECTORY mv [OPTION]... -t DIRECTORY SOURCE... Rename SOURCE to DEST, or move SOURCE(s) to DIRECTORY. Mandatory arguments to long options are mandatory for short options too. --backup[=CONTROL] make a backup of each existing destination file -b like --backup but does not accept an argument % grub-reboot - set the default boot entry for GRUB, for the next boot only grub-reboot [OPTION] MENU_ENTRY Set the default boot menu entry for GRUB, for the next boot only. -h, --help print this message and exit -V, --version print the version information and exit --boot-directory=DIR expect GRUB images under the directory DIR/grub instead of the /boot/grub directory % pldd - display dynamic shared objects linked into a process pldd pid pldd option The pldd command displays a list of the dynamic shared objects that are linked into the process with the -?, --help Display program help message. --usage Display a short usage message. % ldns-zsplit - split up a zone file -n NUMBER Split after NUMBER RRs, ldns-zsplit will not split in the middle of an RRs. Each part is saved with a numerical suffix, starting with .000. The largest suffix is thus .999. -o ORIGIN use ORIGIN as origin when reading the zonefile. -z Sort the zone before splitting. % gsettings - GSettings configuration tool gsettings get SCHEMA [:PATH] KEY gsettings monitor SCHEMA [:PATH] [KEY] gsettings writable SCHEMA [:PATH] KEY gsettings range SCHEMA [:PATH] KEY gsettings describe SCHEMA [:PATH] KEY gsettings set SCHEMA [:PATH] KEY VALUE gsettings reset SCHEMA [:PATH] KEY % lsipc - show information on IPC facilities currently employed in the system lsipc [options] lsipc shows information on the inter-process communication facilities for which the calling process has read access. -i, --id id bined with one of the three resource options: -m, -q or -s. It is possible to override the default output format for this option with the --list, --raw, --json or --export option. -g, --global % resize_reiserfs - resizer tool for the ReiserFS filesystem resize_reiserfs [ -s [+|-]size[K|M|G] ] [ -j dev ] [ -fqv ] device The resize_reiserfs tool resizes an unmounted reiserfs file system. It enlarges or shrinks an reiserfs file system located on a device so that it will have size bytes or size=old_size +(-) size bytes if the + or - prefix is used. If the -s option is not specified, the filesystem will be resized to fill the given ter is given in kilo-, mega-, gigabytes respectively. The resize_reiserfs program does not manipulate the size of the device. If you wish to enlarge a filesys‐ titions, by deleting the partition and recreating it with a larger size (assuming there is free space after the partition in question). Make sure you re-create it with the same starting disk cylinder as % ldns-keygen - generate a DNSSEC key pair ldns-keygen [ OPTION ] DOMAIN with the public DNSKEY, a .private file with the private keydata and a .ds with the DS record of the DNSKEY record. ldns-keygen can also be used to create symmetric keys (for TSIG) by selecting the appropriate algorithm: file. ldns-keygen prints the basename for the key files: K++ % -c, --iteration-count=NUM -l, --buflen=NUM Length of generated hash -s, --salt=NUM Length of salt % The options -v and --version print the version information of the program to standard output and exit. The options -h and --help print a usage information of the program to standard output and stop the pro‐ gram instantly. All other options are assumed to be groffer options. They are internally passed to groffer. They over‐ ride the behavior of the program. The options are optional, they can be omitted. The filespec arguments correspond to the filespec arguments of groffer. So they are either the names of % nameif - name network interfaces based on MAC addresses nameif [-c configfile] [-s] nameif [-c configfile] [-s] {interface macaddress} nameif renames network interfaces based on mac addresses. When no arguments are given /etc/mactab is read. Each line of it contains an interface name and a Ethernet MAC address. Comments are allowed start‐ ing with #. Otherwise the interfaces specified on the command line are processed. nameif looks for the interface with the given MAC address and renames it to the name given. When the -s argument is given all error messages go to the syslog. When the -c argument is given with a file name that file is read instead of /etc/mactab. % ranlib - generate index to archive. ranlib [--plugin name] [-DhHvVt] archive ranlib generates an index to the contents of an archive and stores it in the archive. The index lists each symbol defined by a member of an archive that is a relocatable object file. An archive with such an index speeds up linking to the library and allows routines in the library to call each other without regard to their placement in the archive. The GNU ranlib program is another form of GNU ar; running ranlib is completely equivalent to executing ar -s. % jfs_fscklog - extract a JFS fsck service log into a file and/or format and display the extracted file jfs_fscklog [ -d ] [ -e device ] [ -f output.file ] [ -p ] [ -V ] jfs_fscklog with option -e device extracts the contents of either the most recent or immediately prior (specified with option -p) JFS fsck service log from the specified device, and writes the output to a If the -p option is used, the default file name is fscklog.old. jfs_fscklog with option -d formats and displays the contents of the extracted file. jfs_fscklog with options -d and -e device extracts and displays the JFS fsck service log. -d Format and display a previously extracted JFS fsck service log. % makeinfo [OPTION]... TEXINFO-FILE... Translate Texinfo source documentation to various other formats, by default Info files suitable for read‐ ing online with Emacs or standalone GNU Info. not depend on the installed name. General options: --document-language=STR locale to use in translating Texinfo keywords for the output document (default C). --error-limit=NUM % psfgettable - extract the embedded Unicode character table from a console font psfgettable fontfile [outfile] psfgettable extracts the embedded Unicode character table from a .psf format console font into a human the font is read from standard input. % iptables-xml — Convert iptables-save format to XML iptables-xml [-c] [-v] iptables-xml is used to convert the output of iptables-save into an easily manipulatable XML format to STDOUT. Use I/O-redirection provided by your shell to write to a file. -c, --combine combine consecutive rules with the same matches but different targets. iptables does not currently support more than one target per match, so this simulates that by collecting the targets from con‐ secutive iptables rules into one action tag, but only when the rule matches are identical. Termi‐ nating actions like RETURN, DROP, ACCEPT and QUEUE are not combined with subsequent targets. -v, --verbose Output xml comments containing the iptables line from which the XML is derived % fgconsole - print the number of the active VT. fgconsole [--help|--version|--next-available] If the active Virtual Terminal is /dev/ttyN, then prints N on standard output. If the console is a serial console, then "serial" is printed instead. --next-available Will show the next unallocated virtual terminal. Normally 6 virtual terminals are allocated, with % whoami - print effective userid whoami [OPTION]... Print the user name associated with the current effective user ID. Same as id -un. --help display this help and exit --version output version information and exit Written by Richard Mlynarik. REPORTING BUGS % firewall-offline-cmd - firewalld offline command line client firewall-offline-cmd is an offline command line client of the firewalld daemon. It should be used only if the firewalld service is not running. For example to migrate from system-config-firewall/lokkit or in the install environment to configure firewall settings with kickstart. Some lokkit options can not be automatically converted for firewalld, they will result in an error or with custom rules, modules and masquerading. Check the firewall configuration after using this tool. % pcretest - a program for testing Perl-compatible regular expressions. pcretest [options] [input file [output file]] pcretest was written as a test program for the PCRE regular expression library itself, but it can also be gram; for details of the regular expressions themselves, see the pcrepattern documentation. For details The input for pcretest is a sequence of regular expression patterns and strings to be matched, as described below. The output shows the result of each match. Options on the command line and the patterns control PCRE options and exactly what is output. As PCRE has evolved, it has acquired many different features, and as a result, pcretest now has rather a lot of obscure options for testing every possible feature. Some of these options are specifically % btrfs-select-super - overwrite primary superblock with a backup copy btrfs-select-super -s number for example when write barriers were disabled during a power failure and not all superblocks were written, or if the primary superblock is damaged, eg. accidentally overwritten. The filesystem specified by device must not be mounted. Prior to overwriting the primary superblock, please make sure that the backup copies are valid! To dump a superblock use the btrfs inspect-internal dump-super command, or the obsolete command btrfs-show-super. % localedef - compile locale definition files localedef [options] outputpath localedef --list-archive [options] localedef --delete-from-archive [options] localename ... localedef --add-to-archive [options] compiledpath localedef --version localedef --help localedef --usage The localedef program reads the indicated charmap and input files, compiles them to a binary form quickly put in outputpath. The outputpath argument is interpreted as follows: % bzcat - decompresses files to stdout bzcat [ -s ] [ filenames ... ] coding. Compression is generally considerably better than that achieved by more conventional The command-line options are deliberately very similar to those of GNU gzip, but they are not identical. % Run each Texinfo or (La)TeX FILE through TeX in turn until all cross-references are resolved, building all indices. The directory containing each FILE is searched for included files. The suffix of FILE is used to determine its language ((La)TeX or Texinfo). To process (e)plain TeX files, set the environment variable LATEX=tex. General options: -b, --batch % vim - Vi IMproved, a programmers text editor vim [options] [file ..] vim [options] - vim [options] -t tag vim [options] -q [errorfile] ex view gvim gview evim eview rvim rview rgvim rgview Vim is a text editor that is upwards compatible to Vi. It can be used to edit all kinds of plain text. It is especially useful for editing programs. % raw - bind a Linux raw character device raw /dev/raw/raw raw /dev/raw/raw /dev/ raw -q /dev/raw/raw raw -qa kernel module later). raw is used in two modes: it either sets raw device bindings, or it queries existing bindings. When set‐ % grolbp [ -l ] [ --landscape ] [ -v ] [ --version ] [ -cn ] [ --copies=numcopies ] [ -ppaper_size ] [ --papersize=paper_size ] [ -oorientation ] [ --orientation=orientation ] [ -wwidth ] [ --linewidth=width ] [ -Fdir ] [ --fontdir=dir ] [ -h ] [ --help ] [ files... ] \D'R dh dv' Draw a rule (i.e. a solid black rectangle), with one corner at the current position, and the diag‐ onally opposite corner at the current position +(dh,dv). % vipw, vigr - edit the password or group file vipw [options] vigr [options] vipw edits the password file after setting the appropriate locks, and does any necessary processing after the password file is unlocked. If the password file is already locked for editing by another user, vipw file in the same manner as vipw does the passwd file. ENVIRONMENT If the following environment variable exists, it will be utilized by vipw and vigr: % captest - a program to demonstrate capabilities captest [ --drop-all | --drop-caps | --id ] [ --init-grp ] [ --lock ] [ --text ] captest is a program that demonstrates and prints out the current process capabilities. Each option prints the same report. It will output current capabilities. then it will try to access /etc/shadow directly to show if that can be done. Then it creates a child process that attempts to read /etc/shadow and outputs the results of that. Then it outputs the capabilities that a child process would have. You can also apply file system capabilities to this program to study how they work. For example, filecap /usr/bin/captest chown. Then run captest as a normal user. Another interesting test is to make captest suid root so that you can see what the interaction is between root's credentials and capabilities. For lation is possible. But do not leave this app setuid root after you are don testing so that an attacker cannot take advantage of it. % rmmod - Simple program to remove a module from the Linux Kernel rmmod [-f] [-s] [-v] [modulename] rmmod is a trivial program to remove a module (when module unloading support is provided) from the -v, --verbose Print messages about what the program is doing. Usually rmmod prints messages only if something goes wrong. -f, --force when the kernel was compiled. With this option, you can remove modules which are being used, or which % ipcs - show information on IPC facilities ipcs [options] ipcs shows information on the inter-process communication facilities for which the calling process has read access. By default it shows information about all three resources: shared memory segments, message queues, and semaphore arrays. -i, --id id bined with one of the three resource options: -m, -q or -s. -h, --help Display help text and exit. % routel - list routes with pretty output format routef - flush routes routel [tablenr [raw ip args...]] routef The routel script will list routes in a format that some might consider easier to interpret then the ip route list equivalent. The routef script does not take any arguments and will simply flush the routing table down the drain. FILES /usr/bin/routef /usr/bin/routel % Mandatory arguments to long options are mandatory for short options too. -c, --check checks the syntax only -o, --output=FILE output file -h, --help % uptime - Tell how long the system has been running. uptime [options] uptime gives a one line display of the following information. The current time, how long the system has System load averages is the average number of processes that are either in a runnable or uninterruptable state. A process in a runnable state is either using the CPU or waiting to use the CPU. A process in uninterruptable state is waiting for some I/O access, eg waiting for disk. The averages are taken over the three time intervals. Load averages are not normalized for the number of CPUs in a system, so a load % xz, unxz, xzcat, lzma, unlzma, lzcat - Compress or decompress .xz and .lzma files xz [option...] [file...] unxz is equivalent to xz --decompress. xzcat is equivalent to xz --decompress --stdout. lzma is equivalent to xz --format=lzma. unlzma is equivalent to xz --format=lzma --decompress. lzcat is equivalent to xz --format=lzma --decompress --stdout. When writing scripts that need to decompress files, it is recommended to always use the name xz with appropriate arguments (xz -d or xz -dc) instead of the names unxz and xzcat. % msguniq - unify duplicate translations in message catalog msguniq [OPTION] [INPUTFILE] Unifies duplicate translations in a translation catalog. Finds duplicate translations of the same mes‐ sage ID. Such duplicates are invalid input for other programs like msgfmt, msgmerge or msgcat. By default, duplicates are merged together. When using the --repeated option, only duplicates are output, and all other messages are discarded. Comments and extracted comments will be cumulated, except that if --use-first is specified, they will be taken from the first translation. File positions will be cumu‐ lated. When using the --unique option, duplicates are discarded. Mandatory arguments to long options are mandatory for short options too. Input file location: INPUTFILE % newgrp - log in to a new group newgrp [group] logged in, and the current directory is unchanged, but calculations of access permissions to files are performed with respect to the new group ID. If no group is specified, the GID is changed to the login GID. FILES /etc/group /etc/passwd % nl-qdisc-{add|list|delete} - Manage queueing disciplines The nl-qdisc tools allow to manage and configure queueing disciplines (qdiscs) in the kernel. -h or --help Print help text to console and exit. -v or --version % gnutls-cli - GnuTLS client gnutls-cli [-flags] [-flag [value]] [--option-name[[=| ]value]] [hostname] Simple client program to set up a TLS connection to some other computer. It sets up a TLS connection and forwards data from the standard input to the secured socket and vice versa. -d number, --debug=number constrained to being: in the range 0 through 9999 % xfs_repair - repair an XFS filesystem xfs_repair [ -dfLnPv ] [ -m maxmem ] [ -c subopt=value ] [ -o subopt[=value] ] [ -t interval ] [ -l logdev ] [ -r rtdev ] device xfs_repair -V the device argument which should be the device name of the disk partition or volume containing the filesystem. If given the name of a block device, xfs_repair will attempt to find the raw device associ‐ ated with the specified block device and will use the raw device instead. inconsistent or corrupt. % addgnupghome - Create .gnupg home directories If GnuPG is installed on a system with existing user accounts, it is sometimes required to populate the GnuPG home directory with existing files. Especially a ‘trustlist.txt’ and a keybox with some initial ‘/etc/skel/.gnupg’ to the home directories of the accounts given on the command line. It takes care not to overwrite existing GnuPG home directories. addgnupghome is invoked by root as: % realpath - print the resolved path realpath [OPTION]... FILE... Print the resolved absolute file name; all but the last component must exist -e, --canonicalize-existing all components of the path must exist -m, --canonicalize-missing no path components need exist or be a directory -L, --logical resolve '..' components before symlinks % pvcreate — initialize a disk or partition for use by LVM [-f[f]|--force [--force]] [-y|--yes] [--labelsector] [--bootloaderareasize size] [-M|--metadatatype type] [--[pv]metadatacopies NumberOfCopies] [--metadatasize size] [--metadataignore {y|n}] [--dataalignment alignment] [--dataalignmentoffset alignment_offset] [--restorefile file] [--norestorefile] [--reportfor‐ mat {basic|json}] [--setphysicalvolumesize size] [-u|--uuid uuid] [-Z|--zero {y|n}] PhysicalVolume [Phys‐ icalVolume...] pvcreate initializes PhysicalVolume for later use by the Logical Volume Manager (LVM). Each PhysicalVol‐ ume can be a disk partition, whole disk, meta device, or loopback file. For DOS disk partitions, the first sector with: % stat - display file or file system status stat [OPTION]... FILE... Display file or file system status. Mandatory arguments to long options are mandatory for short options too. -L, --dereference follow links -f, --file-system display file system status instead of file status -c --format=FORMAT % lvmsar — LVM system activity reporter lvmsar % nsupdate - Dynamic DNS update utility nsupdate [-d] [-D] [-L level] [[-g] | [-o] | [-l] | [-y [hmac:]keyname:secret] | [-k keyfile]] [-t timeout] [-u udptimeout] [-r udpretries] [-R randomdev] [-v] [-T] [-P] [-V] [filename] allows resource records to be added or removed from a zone without manually editing the zone file. A single update request can contain requests to add or remove more than one resource record. Zones that are under dynamic control via nsupdate or a DHCP server should not be edited by hand. Manual edits could conflict with dynamic updates and cause data to be lost. The resource records that are dynamically added or removed with nsupdate have to be in the same zone. record. % grub-mkimage - make a bootable image of GRUB grub-mkimage [OPTION...] [OPTION]... [MODULES] Make a bootable image of GRUB. -c, --config=FILE embed FILE as an early config -C, --compression=(xz|none|auto) choose the compression to use for core image -d, --directory=DIR use images and modules under DIR [default=/usr/lib/grub/] % getcap - examine file capabilities getcap [-v] [-r] [-h] filename [ ... ] getcap displays the name and capabilities of each specified -r enables recursive search. -v enables to display all searched entries, even if it has no file-capabilities. -h prints quick usage. filename One file per line. % firewall-config - firewalld GUI configuration tool firewall-config is a GUI configuration tool for firewalld. firewall-config does not support any special options. The only options that can be used are the general options that Gtk uses for Gtk application initialization. For more information on these options, please have a look at the runtime documentation for Gtk. The following options are supported: -h, --help Prints a short help text and exists. % rtmon - listens to and monitors RTnetlink rtmon [ options ] file FILE [ all | LISTofOBJECTS ] rtmon listens on netlink socket and monitors routing table changes. rtmon can be started before the first network configuration command is issued. For example if you insert: rtmon file /var/log/rtmon.log in a startup script, you will be able to view the full history later. Certainly, it is possible to start rtmon at any time. It prepends the history with the state snapshot dumped at the moment of starting. % mkfs.cramfs - make compressed ROM file system mkfs.cramfs [options] directory file Files on cramfs file systems are zlib-compressed one page at a time to allow random read access. The metadata is not compressed, but is expressed in a terse representation that is more space-efficient than conventional file systems. The file system is intentionally read-only to simplify its design; random write access for compressed files is difficult to implement. cramfs ships with a utility (mkcramfs) to pack files into new cramfs images. % named-rrchecker - syntax checker for individual DNS resource records named-rrchecker [-h] [-o origin] [-p] [-u] [-C] [-T] [-P] named-rrchecker read a individual DNS resource record from standard input and checks if it is syntactically correct. The -h prints out the help menu. The -o origin option specifies a origin to be used when interpreting the record. The -p prints out the resulting record in canonical form. If there is no canonical form defined then the record will be printed in unknown record format. The -u prints out the resulting record in unknown record form. % ing, otherwise the expansion of the FILES. together with all the previous files. Operation modes: % pvchange — change attributes of a physical volume [--deltag Tag] [--metadataignore {y|n}] [-h|-?|--help] [--reportformat {basic|json}] [-S|--select Selec‐ tion] [-t|--test] [-v|--verbose] [-a|--all] [-x|--allocatable {y|n}] [-u|--uuid] [PhysicalVolumePath...] pvchange allows you to change the allocation permissions of one or more physical volumes. -a, --all If PhysicalVolumePath is not specified on the command line all physical volumes are searched for and used. % Generate Makefile.in for configure from Makefile.am. Operation modes: --help print this help, then exit --version print version number, then exit -v, --verbose verbosely list files processed % ctrlaltdel - set the function of the Ctrl-Alt-Del combination ctrlaltdel hard|soft Based on examination of the linux/kernel/reboot.c code, it is clear that there are two supported func‐ tions that the Ctrl-Alt-Del sequence can perform. is the default. soft Make the kernel send the SIGINT (interrupt) signal to the init process (this is always the process version that you are currently using. % file — determine file type file [-bcdEhiklLNnprsvzZ0] [--apple] [--extension] [--mime-encoding] [--mime-type] [-e testname] [-F separator] [-f namefile] [-m magicfiles] [-P name=value] file ... file -C [-m magicfiles] file [--help] file tests each argument in an attempt to classify it. There are three sets of tests, performed in this order: filesystem tests, magic tests, and language tests. The first test that succeeds causes the file type to be printed. The type printed will usually contain one of the words text (the file contains only printing characters and a few common control characters and is probably safe to read on an ASCII terminal), executable (the file % firewall-cmd - firewalld command line client firewall-cmd is the command line client of the firewalld daemon. It provides interface to manage runtime and permanent configuration. things can get changed in the runtime or permanent configuration. The following options are supported: General Options -h, --help % Reads a PIC program as input; produces an image file (by default in Portable Network Graphics format) images of mathematical formulae. PIC is a rather expressive graphics minilanguage suitable for producing box-and-arrow diagrams of the kind frequently used in technical papers and textbooks. The language is sufficiently flexible to be quite useful for state charts, Petri-net diagrams, flow charts, simple circuit schematics, jumper lay‐ outs, and other kinds of illustration involving repetitive uses of simple geometric forms and splines. Because PIC descriptions are procedural and object-based, they are both compact and easy to modify. The PIC language is fully documented in Making Pictures With GNU PIC, a document which is part of the % gpasswd - administer /etc/group and /etc/gshadow gpasswd [option] group The gpasswd command is used to administer /etc/group, and /etc/gshadow. Every group can have administrators, members and a password. System administrators can use the -A option to define group administrator(s) and the -M option to define members. They have all rights of group administrators and members. gpasswd called by a group administrator with a group name only prompts for the new password of the group. the password. % fmt - simple optimal text formatter fmt [-WIDTH] [OPTION]... [FILE]... Reformat each paragraph in the FILE(s), writing to standard output. The option -WIDTH is an abbreviated form of --width=DIGITS. With no FILE, or when FILE is -, read standard input. Mandatory arguments to long options are mandatory for short options too. -c, --crown-margin preserve indentation of first two lines -p, --prefix=STRING % lvmdump [-a] [-c] [-d directory] [-h] [-l] [-m] [-p] [-s] [-u] for submission along with a problem report. The content of the tarball is as follows: - dmsetup info - table of currently running processes - recent entries from /var/log/messages (containing system messages) - complete lvm configuration and cache (content of /etc/lvm) - list of device nodes present under /dev - list of files present /sys/block - list of files present /sys/devices/virtual/block % ldns-notify - notify DNS servers that updates are available ldns-notify [options] -z zone servers the master servers. It can perform TSIG signatures and it can add a SOA serial number of the updated zone. If a server already has that serial number it will disregard the message. -z zone The zone that is updated. -h Show usage and exit -v Show the version and exit % mmroff - cross reference preprocessor mmroff [ -x ] groff_arguments mmroff is a simple preprocessor for groff, it is used for expanding cross references in mm, see to do the real processing when the cross reference file is up to date. isn't always needed to have accurate cross references and by using this option groff will only be run once. FILES % readelf - Displays information about ELF files. readelf [-a|--all] [-h|--file-header] [-l|--program-headers|--segments] [-S|--section-headers|--sections] [-g|--section-groups] [-t|--section-details] [-e|--headers] [-s|--syms|--symbols] [--dyn-syms] [-n|--notes] [-r|--relocs] [-u|--unwind] [-d|--dynamic] [-V|--version-info] % dumpkeys - dump keyboard translation tables dumpkeys [ -hilfn -ccharset --help --short-info --long-info --numeric --full-table --funcs-only --keys-only --compose-only --charset=charset ] dumpkeys writes, to the standard output, the current contents of the keyboard driver's translation Using the various options, the format of the output can be controlled and also other information from the -h --help Prints the program's version number and a short usage message to the program's standard error out‐ put and exits. % external-journal ] [ -E extended_options ] [ -z undo_file ] device use a journal, if the system has been shut down uncleanly without any errors, normally, after replaying the committed transactions in the journal, the file system should be marked as clean. Hence, for indicates that further checking is required. -n option is specified, and -c, -l, or -L options are not specified. However, even if it is safe to do % numastat numastat - Show per-NUMA-node memory statistics for processes and the operating system numastat numastat [-V] numastat [|...] numastat [-c] [-m] [-n] [-p |] [-s[]] [-v] [-z] [|...] numastat with no command options or arguments at all, displays per-node NUMA hit and miss system statis‐ previous long-standing numastat perl script, written by Andi Kleen. The default numastat statistics shows per-node numbers (in units of pages of memory) in these categories: % jfs_logdump - dump a JFS formatted device's journal log jfs_logdump [ -a ] device jfs_logdump dumps the contents of the journal log from the specified JFS formatted device into output file ./jfslog.dmp. device is the special file name corresponding to the actual device from which the journal log will be jfs_logdump must be run as root. -a Dump the entire contents of the journal log instead of just the committed transactions since the last synch point. % man - an interface to the on-line reference manuals man [-C file] [-d] [-D] [--warnings[=warnings]] [-R encoding] [-L locale] [-m system[,...]] [-M path] [-S list] [-e extension] [-i|-I] [--regex|--wildcard] [--names-only] [-a] [-u] [--no-subpages] [-P pager] [-r prompt] [-7] [-E encoding] [--no-hyphenation] [--no-justification] [-p string] [-t] [-T[device]] [-H[browser]] [-X[dpi]] [-Z] [[section] page ...] ... man -k [apropos options] regexp ... man -K [-w|-W] [-S list] [-i|-I] [--regex] [section] term ... man -f [whatis options] page ... man -l [-C file] [-d] [-D] [--warnings[=warnings]] [-R encoding] [-L locale] [-P pager] [-r prompt] [-7] [-E encoding] [-p string] [-t] [-T[device]] [-H[browser]] [-X[dpi]] [-Z] file ... man -w|-W [-C file] [-d] [-D] page ... man -c [-C file] [-d] [-D] page ... man [-?V] % scp — secure copy (remote file copy program) needed for authentication. file names containing ‘:’ as host specifiers. Copies between two remote hosts are also permitted. The options are as follows: % xfs_quota - manage use of quota on XFS filesystems xfs_quota [ -x ] [ -p prog ] [ -c cmd ] ... [ -d project ] ... [ -D projects_file ] [ -P projid_file ] [ path ... ] xfs_quota -V xfs_quota is a utility for reporting and editing various aspects of filesystem quota. The options to xfs_quota are: gram exits. -p prog Set the program name for prompts and some error messages, the default value is xfs_quota. % talk - Talk client talk [OPTION...] person [ttyname] Talk to another user. -?, --help give this help list --usage give a short usage message -V, --version print program version % With no FILE, or when FILE is -, read standard input. Mandatory arguments to long options are mandatory for short options too. -d, --decode decode data -i, --ignore-garbage when decoding, ignore non-alphabet characters % addpart - tell the kernel about the existence of a partition addpart device partition start length addpart tells the Linux kernel about the existence of the specified partition. The command is a simple wrapper around the "add partition" ioctl. PARAMETERS device The disk device. partition The partition number. % pvremove — remove a physical volume [-f[f]|--force [--force]] [--reportformat {basic|json}] [-y|--yes] PhysicalVolume [PhysicalVolume...] pvremove wipes the label on a device so that LVM will no longer recognise it as a physical volume. -ff, --force --force Force the removal of a physical volume belonging to an existing volume group. Normally vgre‐ by some active logical volume. % pwconv, pwunconv, grpconv, grpunconv - convert to and from shadow passwords and groups pwconv [options] pwunconv [options] grpconv [options] grpunconv [options] The pwconv command creates shadow from passwd and an optionally existing shadow. The pwunconv command creates passwd from passwd and shadow and then removes shadow. The grpconv command creates gshadow from group and an optionally existing gshadow. % sleep - delay for a specified amount of time sleep NUMBER[SUFFIX]... sleep OPTION trary floating point number. Given two or more arguments, pause for the amount of time specified by the sum of their values. --help display this help and exit --version output version information and exit % vgcfgrestore — restore volume group descriptor area vgcfgbackup. You can specify a backup file with --file. If no backup file is specified, the most recent -l, --list % rtpr - replace backslashes with newlines. rtpr is a trivial bash script which converts backslashes in standard input to newlines. It's sole purpose is to be fed with input from ip when executed with it's --oneline flag. ip --oneline address show | rtpr Undo oneline converted ip-address output. Stephen Hemminger % useradd - create a new user or update default new user information useradd [options] LOGIN useradd -D useradd -D [options] When invoked without the -D option, the useradd command creates a new user account using the values specified on the command line plus the default values from the system. Depending on command line options, initial files. By default, a group will also be created for the new user (see -g, -N, -U, and USERGROUPS_ENAB). % dnssec-keyfromlabel - DNSSEC key generation tool [-D sync date/offset] [-E engine] [-f flag] [-G] [-I date/offset] [-i interval] [-k] [-K directory] [-L ttl] [-n nametype] [-P date/offset] [-P sync date/offset] [-p protocol] [-R date/offset] [-S key] [-t type] [-v level] [-V] [-y] {name} dnssec-keyfromlabel generates a key pair of files that referencing a key object stored in a cryptographic hardware service module (HSM). The private key file can be used for DNSSEC signing of zone data as if it were a conventional signing key created by dnssec-keygen, but the key material is stored within the HSM, and the actual signing takes place there. key is being generated. % xzgrep - search compressed files for a regular expression xzgrep [grep_options] [-e] pattern file... xzegrep ... xzfgrep ... lzgrep ... lzegrep ... lzfgrep ... % chcpu - configure CPUs chcpu -c|-d|-e|-g cpu-list chcpu -p mode chcpu -r|-h|-V chcpu can modify the state of CPUs. It can enable or disable CPUs, scan for new CPUs, change the CPU dispatching mode of the underlying hypervisor, and request CPUs from the hypervisor (configure) or return CPUs to the hypervisor (deconfigure). Some options have a cpu-list argument. Use this argument to specify a comma-separated list of CPUs. The % nologin - politely refuse a login nologin [-V] [-h] nologin displays a message that an account is not available and exits non-zero. It is intended as a replacement shell field to deny login access to an account. If the file /etc/nologin.txt exists, nologin displays its contents to the user instead of the default message. -h, --help Display help text and exit. % pvs — report information about physical volumes [-d|--debug] [-h|-?|--help] [--ignorelockingfailure] [--ignoreskippedcluster] [--logonly] [--namepre‐ fixes] [--noheadings] [--nosuffix] [-P|--partial] [--reportformat {basic|json}] [--rows] [--segments] [--separator Separator] [--unbuffered] [--units hHbBsSkKmMgGtTpPeE] [--unquoted] [-v|--verbose] [--ver‐ sion] [PhysicalVolume [PhysicalVolume...]] pvs produces formatted output about physical volumes. % agetty - alternative Linux getty agetty [options] port [baud_rate...] [term] agetty opens a tty port, prompts for a login name and invokes the /bin/login command. It is normally agetty has several non-standard features that are useful for hardwired and for dial-in lines: when it reads a login name. The program can handle 7-bit characters with even, odd, none or space Control-U (kill); DEL and backspace (erase); carriage return and line feed (end of line). See also the --erase-chars and --kill-chars options. % ldns-revoke - sets the revoke bit of a DNSKEY ldns-revoke file ldns-revoke is used to revoke a public DNSKEY RR. When run it will read file with a DNSKEY RR in it, sets the revoke bit and write back the output to file . -n Write the result to stdout instead of a file Written by the ldns team as an example for ldns usage. REPORTING BUGS Report bugs to . % ebtables [-t table ] -[ACDI] chain rule specification [match extensions] [watcher extensions] target ebtables [-t table ] -P chain ACCEPT | DROP | RETURN ebtables [-t table ] -F [chain] ebtables [-t table ] -Z [chain] ebtables [-t table ] -N chain [-P ACCEPT | DROP | RETURN] ebtables [-t table ] -X [chain] ebtables [-t table ] -E old-chain-name new-chain-name ebtables [-t table ] --init-table ebtables [-t table ] [--atomic-file file] --atomic-commit ebtables [-t table ] [--atomic-file file] --atomic-init ebtables [-t table ] [--atomic-file file] --atomic-save % yacc - GNU Project parser generator yacc [OPTION]... FILE information. Written by Paul Eggert. REPORTING BUGS Report bugs to . % systemd-analyze - Analyze system boot-up performance % dnssec-revoke - set the REVOKED bit on a DNSSEC key dnssec-revoke [-hr] [-v level] [-V] [-K directory] [-E engine] [-f] [-R] {keyfile} creates a new pair of key files containing the now-revoked key. -h Emit usage message and exit. -K directory Sets the directory in which the key files are to reside. -r % lspci - list all PCI devices lspci [options] lspci is a utility for displaying information about PCI buses in the system and devices connected to them. By default, it shows a brief list of devices. Use the options described below to request either a more verbose output or output intended for parsing by other programs. If you are going to report bugs in PCI device drivers or in lspci itself, please include output of "lspci -vvx" or even better "lspci -vvxxx" (however, see below for possible caveats). Some parts of the output, especially in the highly verbose modes, are probably intelligible only to expe‐ rienced PCI hackers. For exact definitions of the fields, please consult either the PCI specifications or % screen [ -options ] [ cmd [ args ] ] screen -r [[pid.]tty[.host]] screen -r sessionowner/[[pid.]tty[.host]] Screen is a full-screen window manager that multiplexes a physical terminal between several processes dards (e.g. insert/delete line and support for multiple character sets). There is a scrollback history buffer for each virtual terminal and a copy-and-paste mechanism that allows moving text regions between windows. When screen is called, it creates a single window with a shell in it (or the specified command) and then gets out of your way so that you can use the program as you normally would. Then, at any time, you can % kernel-install - Add and remove kernel and initramfs images to and from /boot kernel-install is used to install and remove kernel and initramfs images to and from /boot. kernel-install will execute the files located in the directory /usr/lib/kernel/install.d/ and the local administration directory /etc/kernel/install.d/. All files are collectively sorted and executed in lexical order, regardless of the directory in which they live. However, files with identical filenames replace each other. Files in /etc/kernel/install.d/ take precedence over files with the same name in if needed; a symbolic link in /etc/kernel/install.d/ with the same name as an executable in /usr/lib/kernel/install.d/, pointing to /dev/null, disables the executable entirely. Executables must have the extension ".install"; other extensions are ignored. % setterm - set terminal attributes setterm [options] setterm writes to standard output a character string that will invoke the specified terminal capabili‐ ties. Where possible terminfo is consulted to find the string to use. Some options however (marked minal type is "con" or "linux" the string that invokes the specified capabilities on the PC Minix virtual console driver is output. Options that are not implemented by the terminal are ignored. For boolean options (on or off), the default is on. % mapscrn - load screen output mapping table mapscrn [-v] [-o map.orig] mapfile The mapscrn command is obsolete - its function is now built-in into setfont. However, for backwards com‐ patibility it is still available as a separate command. The mapscrn command loads a user defined output character mapping table into the console driver. The con‐ character set. When the -o option is given, the old map is saved in map.orig. USE There are two kinds of mapping tables: direct-to-font tables, that give a font position for each user byte value, and user-to-unicode tables that give a unicode value for each user byte. The corresponding % lvcreate - create a logical volume in an existing volume group lvcreate [-a|--activate [a][e|l|s]{y|n}] [--addtag Tag] [--alloc AllocationPolicy] [-A|--autobackup {y|n}] [-H|--cache] [--cachemode {passthrough|writeback|writethrough}] [--cachepolicy Policy] [--cachepool CachePoolLogicalVolume] [--cachesettings Key=Value] [-c|--chunksize ChunkSize] [--command‐ [--errorwhenfull {y|n}] [{-l|--extents LogicalExtentsNumber[%{FREE|PVS|VG}] | -L|--size LogicalVolume‐ Size} [-i|--stripes Stripes [-I|--stripesize StripeSize]]] [-h|-?|--help] [-K|--ignoreactivationskip] Mirrors [--corelog|--mirrorlog {disk|core|mirrored}] [--nosync] [-R|--regionsize MirrorLogRegionSize]] [--monitor {y|n}] [-n|--name LogicalVolume] [--noudevsync] [-p|--permission {r|rw}] [-M|--persistent {y|n}] [--poolmetadatasize MetadataVolumeSize] [--poolmetadataspare {y|n}] [--[raid]maxrecoveryrate Rate] [--[raid]minrecoveryrate Rate] [-r|--readahead {ReadAheadSectors|auto|none}] [--reportformat {basic|json}] [-k|--setactivationskip {y|n}] [-s|--snapshot] [-V|--virtualsize VirtualSize] [-t|--test] [-T|--thin] [--thinpool ThinPoolLogicalVolume] [--type SegmentType] [-v|--verbose] [-W|--wipesignatures {y|n}] [-Z|--zero {y|n}] [VolumeGroup | {ExternalOrigin|Origin|Pool}LogicalVolume % renice - alter priority of running processes renice [-n] priority [-g|-p|-u] identifier... renice alters the scheduling priority of one or more running processes. The first argument is the prior‐ ity value to be used. The other arguments are interpreted as process IDs (by default), process group IDs, user IDs, or user names. renice'ing a process group causes all processes in the process group to have their scheduling priority altered. renice'ing a user causes all processes owned by the user to have their scheduling priority altered. -n, --priority priority Specify the scheduling priority to be used for the process, process group, or user. Use of the option -n or --priority is optional, but when used it must be the first argument. % eqn - format equations for troff or MathML eqn [-rvCNR] [-d xy] [-T name] [-M dir] [-f F] [-s n] [-p n] [-m n] [files...] eqn compiles descriptions of equations embedded within troff input files into commands that are under‐ stood by troff. Normally, it should be invoked using the -e option of groff. The syntax is quite com‐ patible with Unix eqn. The output of GNU eqn cannot be processed with Unix troff; it must be processed with GNU troff. If no files are given on the command line, the standard input is read. A filename of - causes the standard input to be read. eqn searches for the file eqnrc in the directories given with the -M option first, then in /usr/lib/groff/site-tmac, /usr/share/groff/site-tmac, and finally in the standard macro directory option prevents this. % who - show who is logged on Print information about users who are currently logged in. -a, --all same as -b -d --login -p -r -t -T -u -b, --boot time of last system boot -d, --dead print dead processes % vgconvert - convert volume group metadata format tor] [--bootloaderareasize size] [-M|--metadatatype type] [--pvmetadatacopies NumberOfCopies] [--meta‐ into the same space. Examples % zgrep - search possibly compressed files for a regular expression zgrep [ grep_options ] [ -e ] pattern filename... Zgrep invokes grep on compressed or gzipped files. All options specified are passed directly to grep. If no file is specified, then the standard input is decompressed if necessary and fed to grep. Otherwise the given files are uncompressed if necessary and fed to grep. If the GREP environment variable is set, zgrep uses it as the grep program to be invoked. BUGS The following grep options are not supported: --dereference-recursive (-R), --directories (-d), % fdisk - manipulate disk partition table fdisk [options] device fdisk -l [device...] fdisk is a dialog-driven program for creation and manipulation of partition tables. It understands GPT, MBR, Sun, SGI and BSD partition tables. in the partition table, usually found in sector 0 of the disk. (In the BSD world one talks about `disk slices' and a `disklabel'.) All partitioning is driven by device I/O limits (the topology) by default. fdisk is able to optimize the % truncate - shrink or extend the size of a file to the specified size truncate OPTION... FILE... Shrink or extend the size of each FILE to the specified size A FILE argument that does not exist is created. If a FILE is larger than the specified size, the extra data is lost. If a FILE is shorter, it is extended and the extended part (hole) reads as zero bytes. Mandatory arguments to long options are mandatory for short options too. -c, --no-create do not create any files % gpinyin - Chinese European-like writing within groff gpinyin [-] [--] [ filespec ....] gpinyin -h|--help gpinyin -v|--version groff(7) files. Breaking Options An option is breaking, when the program just writes the information that was asked for and then stops. All other arguments will be ignored by that. The breaking options are here -h | --help % neqn - format equations for ascii output neqn [eqn options] device. for very simple input). % rndc-confgen - rndc key generation tool rndc-confgen [-a] [-A algorithm] [-b keysize] [-c keyfile] [-h] [-k keyname] [-p port] [-r randomfile] [-s address] [-t chrootdir] [-u user] rndc-confgen generates configuration files for rndc. It can be used as a convenient alternative to writing the rndc.conf file and the corresponding controls and key statements in named.conf by hand. Alternatively, it can be run with the -a option to set up a rndc.key file and avoid the need for a rndc.conf file and a controls statement altogether. -a specified as when BIND was built) that is read by both rndc and named on startup. The rndc.key file defines a default command channel and authentication key allowing rndc to communicate with named on % setarch - change reported architecture in new program environment and set personality flags setarch arch [options] [program [argument...]] arch [options] [program [argument...]] setarch --list|-h|-V various personality options. The default program is /bin/sh. --list List the architectures that setarch knows about. Whether setarch can actually set each of these architectures depends on the running kernel. % pathchk - check whether file names are valid or portable Diagnose invalid or unportable file names. -p check for most POSIX systems -P check for empty names and leading "-" --portability check for all POSIX systems (equivalent to -p -P) --help display this help and exit % -b print the blocks which are reserved as bad in the filesystem. -o superblock=superblock by a filesystem wizard who is examining the remains of a very badly corrupted filesystem. % arp - manipulate the system ARP cache arp [-vn] [-H type] [-i if] [-ae] [hostname] arp [-v] [-i if] -d hostname [pub] arp [-v] [-H type] [-i if] -s hostname hw_addr [temp] arp [-v] [-H type] [-i if] -s hostname hw_addr [netmask nm] pub arp [-v] [-H type] [-i if] -Ds hostname ifname [netmask nm] pub arp [-vnD] [-H type] [-i if] -f [filename] % nl-qdisc-{add|list|delete} - Manage queueing disciplines The nl-qdisc tools allow to manage and configure queueing disciplines (qdiscs) in the kernel. -h or --help Print help text to console and exit. -v or --version % iptables [-t table] {-A|-C|-D} chain rule-specification ip6tables [-t table] {-A|-C|-D} chain rule-specification iptables [-t table] -I chain [rulenum] rule-specification iptables [-t table] -R chain rulenum rule-specification iptables [-t table] -D chain rulenum iptables [-t table] -S [chain [rulenum]] iptables [-t table] {-F|-L|-Z} [chain [rulenum]] [options...] % false - do nothing, unsuccessfully false [ignored command line arguments] false OPTION Exit with a status code indicating failure. --help display this help and exit --version output version information and exit Please refer to your shell's documentation for details about the options it supports. % objcopy - copy and translate object files objcopy [-F bfdname|--target=bfdname] [-I bfdname|--input-target=bfdname] [-O bfdname|--output-target=bfdname] [-B bfdarch|--binary-architecture=bfdarch] [-S|--strip-all] [-g|--strip-debug] [-K symbolname|--keep-symbol=symbolname] [-N symbolname|--strip-symbol=symbolname] [--strip-unneeded-symbol=symbolname] [-G symbolname|--keep-global-symbol=symbolname] [--localize-hidden] [-L symbolname|--localize-symbol=symbolname] [--globalize-symbol=symbolname] [-W symbolname|--weaken-symbol=symbolname] % Set up images to boot from DEVICE. You should not normally run this program directly. Use grub-install instead. -a, --allow-floppy make the drive also bootable as floppy (default for fdX devices). May break on some BIOSes. -b, --boot-image=FILE use FILE as the boot image [default=boot.img] -c, --core-image=FILE % xtotroff - convert X font metrics into GNU troff font metrics xtotroff [ -rresolution ] [ -spoint-size ] [ -v ] FontMap fonts listed. Each line in FontMap consists of GNU troff font name and an X font name (XLFD) pattern, separated by whitespace. Example: The wildcards in the patterns are filled with the arguments to the -r and -s switches. If a font name is still ambiguous, xtotroff aborts. It is possible to have whitespace between a command line option and its parameter. % lvm [command|file] If lvm is invoked with no arguments it presents a readline prompt (assuming it was compiled with readline If lvm is invoked with argv[0] set to the name of a specific LVM command (for example by using a hard or soft link) it acts as that command. On invocation, lvm requires that only the standard file descriptors stdin, stdout and stderr are avail‐ % sulogin - single-user login sulogin [options] [tty] sulogin is invoked by init when the system goes into single-user mode. The user is prompted: Give root password for system maintenance (or type Control-D for normal startup): If the root account is locked and --force is specified, no password is required. sulogin will be connected to the current terminal, or to the optional tty device that can be specified on the command line (typically /dev/console). % mail -h | --help mail [-BDdEFintv~] [-A account] [-a attachment] [-b bcc-addr] [-c cc-addr] [-q quote-file] [-r from-addr] [-S variable[=value]] [-s subject] [-X cmd] [-.] to-addr ... [-- mta-option ...] mail [-BDdEeHiNnRv~#] [-A account] [-L spec-list] [-r from-addr] [-S variable[=value]] [-X cmd] -f [file] [-- mta-option ...] mail [-BDdEeHiNnRv~#] [-A account] [-L spec-list] [-r from-addr] [-S variable[=value]] [-u user] [-X cmd] [-- mta-option ...] % curl-config - Get information about a libcurl installation curl-config [options] curl-config displays information about the curl and libcurl installation. --ca Displays the built-in path to the CA cert bundle this libcurl uses. --cc Displays the compiler used to build libcurl. --cflags Set of compiler options (CFLAGS) to use when compiling files that use libcurl. Currently that is only the include path to the curl include files. % grn - groff preprocessor for gremlin files grn [ -Cv ] [ -Tdev ] [ -Mdir ] [ -Fdir ] [ file... ] grn is a preprocessor for including gremlin pictures in groff input. grn writes to standard output, pro‐ cessing only input lines between two that start with .GS and .GE. Those lines must contain grn commands (see below). These commands request a gremlin file, and the picture in that file is converted and placed justify the whole gremlin picture (default justification is center). If no file is mentioned, the stan‐ dard input is read. At the end of the picture, the position on the page is the bottom of the gremlin picture. If the grn entry is ended with .GF instead of .GE, the position is left at the top of the pic‐ ture. Please note that currently only the -me macro package has support for .GS, .GE, and .GF. % lvreduce — reduce the size of a logical volume [-v|--verbose] [--version] [-f|--force] [--noudevsync] {-l|--extents [-]LogicalExtentsNum‐ ber[%{VG|LV|FREE|ORIGIN}] | -L|--size [-]LogicalVolumeSize[bBsSkKmMgGtTpPeE]} [-n|--nofsck] [--reportfor‐ lvreduce allows you to reduce the size of a logical volume. Be careful when reducing a logical volume's size, because data in the reduced part is lost!!! You should therefore ensure that any filesystem on the volume is resized before running lvreduce so that the extents that are to be removed are not in use. Sizes will be rounded if necessary - for example, the volume size must be an exact number of extents and the size of a striped segment must be a multiple of the number of stripes. % grub-glue-efi - generate a fat binary for EFI -o, --output=FILE % lkbib - search bibliographic databases lkbib [ -v ] [ -ifields ] [ -pfilename ] [ -tn ] key... lkbib searches bibliographic databases for references that contain the keys key... and prints any refer‐ ences found on the standard output. lkbib will search any databases given by -p options, and then a default database. The default database is taken from the REFER environment variable if it is set, other‐ wise it is /usr/dict/papers/Ind. For each database filename to be searched, if an index filename.i cre‐ It is possible to have whitespace between a command line option and its parameter. -v Print the version number. % should give you access to the complete manual. % delpart - tell the kernel to forget about a partition delpart device partition delpart asks the Linux kernel to forget about the specified partition (a number) on the specified device. The command is a simple wrapper around the "del partition" ioctl. AVAILABILITY The delpart command is part of the util-linux package and is available from ftp://ftp.ker‐ nel.org/pub/linux/utils/util-linux/. % zramctl - set up and control zram devices Get info: zramctl [options] Reset zram: zramctl -r zramdev... Print name of first unused zram device: zramctl -f Set up a zram device: % gpg-connect-agent - Communicate with a running agent gpg-connect-agent [options][commands] The gpg-connect-agent is a utility to communicate with a running gpg-agent. It is useful to check out the commands gpg-agent provides using the Assuan interface. It might also be useful for scripting simple applications. Input is expected at stdin and out put gets printed to stdout. It is very similar to running gpg-agent in server mode; but here we connect to a running instance. -v --verbose Output additional information while running. % gxditview - display groff intermediate output files gxditview [-toolkitoption ...] [-option ...] [filename] several ways to use gxditview. gxditview filename. If filename is -, gxditview will read the standard input; filename cannot be omit‐ ted. The groff intermediate output is different for all devices. gxditview can view it for all devices, but the quality is device dependent. The best results are achieved with the X* devices for groff's option -T. There are four X* devices: % wdctl - show hardware watchdog status wdctl [options] [device...] Show hardware watchdog status. The default device is /dev/watchdog. If more than one device is speci‐ fied then the output is separated by one blank line. -f, --flags list Print only the specified flags. -F, --noflags Do not print information about flags. % grub-mkstandalone - make a memdisk-based GRUB image grub-mkstandalone [OPTION...] [OPTION] SOURCE... Generate a standalone image (containing all modules) in the selected format --compress=no|xz|gz|lzo compress GRUB files [optional] -d, --directory=DIR use images and modules under DIR [default=/usr/lib/grub/] --fonts=FONTS install FONTS [default=unicode] % nslookup - query Internet name servers interactively nslookup [-option] [name | -] [server] Nslookup is a program to query Internet domain name servers. Nslookup has two modes: interactive and non-interactive. Interactive mode allows the user to query name servers for information about various hosts and domains or to print a list of hosts in a domain. Non-interactive mode is used to print just the name and requested information for a host or domain. % grub-render-label - generate a .disk_label for Apple Macs. Render Apple .disk_label. -b, --bgcolor=COLOR use COLOR for background -c, --color=COLOR use COLOR for text -f, --font=FILE % ar - create, modify, and extract from archives The GNU ar program creates, modifies, and extracts from archives. An archive is a single file holding a collection of other files in a structure that makes it possible to retrieve the original individual files (called members of the archive). The original files' contents, mode (permissions), timestamp, owner, and group are preserved in the archive, and can be restored on extraction. GNU ar can maintain archives whose members have names of any length; however, depending on how ar is % btrfs-image - create/restore an image of the filesystem btrfs-image [options] btrfs-image is used to create an image of a btrfs filesystem. All data will be zeroed, but metadata and the like is preserved. Mainly used for debugging purposes. In the dump mode, source is the btrfs device/file and target is the output file (use - for stdout). In the restore mode (option -r), source is the dumped image and target is the btrfs device/file. -r primary device, so that file system can be restored by running tree log reply if possible. To restore % jfs_mkfs - create a JFS formatted partition jfs_mkfs [options] device [ blocks ] jfs_mkfs is used to create (format) a JFS partition. jfs_mkfs must be run as root. system and/or JFS journal will be created. blocks is the number of blocks to be used for the file sys‐ tem. If omitted, jfs_mkfs automatically figures the file system size. WARNING jfs_mkfs will destroy all data on the specified device! % vim - Vi IMproved, a programmers text editor vim [options] [file ..] vim [options] - vim [options] -t tag vim [options] -q [errorfile] ex view gvim gview evim eview rvim rview rgvim rgview Vim is a text editor that is upwards compatible to Vi. It can be used to edit all kinds of plain text. It is especially useful for editing programs. % btrfs-inspect-internal - query various internal information btrfs inspect-internal simple UI to an ioctl or a more complex query that assembles the result from several internal structures. The latter usually requires calls to privileged ioctls. dump-super [options] [device...] (replaces the standalone tool btrfs-show-super) Show btrfs superblock information stored on given devices in textual form. By default the first superblock is printed, more details about all copies or additional backup data can be printed. % vdir - list directory contents vdir [OPTION]... [FILE]... List information about the FILEs (the current directory by default). Sort entries alphabetically if none of -cftuvSUX nor --sort is specified. Mandatory arguments to long options are mandatory for short options too. -a, --all do not ignore entries starting with . -A, --almost-all do not list implied . and .. % ul - do underlining ul [options] [file...] ul reads the named files (or standard input if none are given) and translates occurrences of underscores to the sequence which indicates underlining for the terminal in use, as specified by the environment variable TERM. The terminfo database is read to determine the appropriate sequences for underlining. If the terminal is incapable of underlining but is capable of a standout mode, then that is used instead. terminal cannot underline, underlining is ignored. -i, --indicated Underlining is indicated by a separate line containing appropriate dashes `-'; this is useful when you want to look at the underlining which is present in an nroff output stream on a crt-terminal. % systool - view system device information by bus, class, and topology systool [options [device]] Calling systool without parameters will present all available bus types, device classes, and root devices. When device is supplied, the information reqested by options is shown only for the specified device, oth‐ erwise all present devices are displayed. systool uses APIs provided by libsysfs to gather information. systool runs only on Linux systems running -a Show attributes of the requested resource % udevadm - udev management tool udevadm [--debug] [--version] [--help] udevadm info options udevadm trigger [options] udevadm settle [options] udevadm control command udevadm monitor [options] udevadm test [options] devpath % true - do nothing, successfully true [ignored command line arguments] true OPTION Exit with a status code indicating success. --help display this help and exit --version output version information and exit Please refer to your shell's documentation for details about the options it supports. % loadunimap - load the kernel unicode-to-font mapping table loadunimap [ -C console ] [ -o oldmap ] [ map ] The loadunimap command is obsolete - its function is now built-in into setfont. However, for backwards compatibility it is still available as a separate command. The program loadunimap loads the specified map in the kernel unicode-to-font mapping table. If no map is given def is assumed. The default extension (that can be omitted) is .uni. If the -o oldmap option is given, the old map is saved in the file specified. Usually one does not call loadunimap directly - its function is also built into setfont. % keytab. operation must be one of the following: list Lists the keys in a keytab showing version number and principal name. change Uses the kadmin protocol to update the keys in the Kerberos database to new randomly-generated keys, and updates the keys in the keytab to match. If a key's version number doesn't match the version number stored in the Kerberos server's database, then the operation will fail. Old keys are retained in the keytab so that existing tickets continue to work. If the -i flag is given, % hostid - print the numeric identifier for the current host hostid [OPTION] Print the numeric identifier (in hexadecimal) for the current host. --help display this help and exit --version output version information and exit Written by Jim Meyering. REPORTING BUGS % kdestroy - destroy Kerberos tickets kdestroy [-A] [-q] [-c cache_name] The kdestroy utility destroys the user's active Kerberos authorization tickets by overwriting and delet‐ ing the credentials cache that contains them. If the credentials cache is not specified, the default credentials cache is destroyed. -A Destroys all caches in the collection, if a cache collection is available. -q Run quietly. Normally kdestroy beeps if it fails to destroy the user's tickets. The -q flag sup‐ presses this behavior. -c cache_name % sysctl - configure kernel parameters at runtime sysctl [options] [variable[=value]] [...] sysctl -p [file or regexp] [...] sysctl is used to modify kernel parameters at runtime. The parameters available are those listed under /proc/sys/. Procfs is required for sysctl support in Linux. You can use sysctl to both read and write sysctl data. PARAMETERS variable The name of a key to read from. An example is kernel.ostype. The '/' separator is also accepted in place of a '.'. variable=value % ldns-testns - simple fake nameserver tool ldns-testns [ OPTION ] datafile ldns-testns can be used to provide answers to DNS queries for testing. The answers are premade, and can be tailored to testing needs. The answers can be wildly invalid or unparseable. ldns-testns is not meant for production use. % ipcrm - remove certain IPC resources ipcrm [options] ipcrm {shm|msg|sem} id... ipcrm removes System V interprocess communication (IPC) objects and associated data structures from the system. In order to delete such objects, you must be superuser, or the creator or owner of the object. System V IPC objects are of three types: shared memory, message queues, and semaphores. Deletion of a message queue or semaphore object is immediate (regardless of whether any process still holds an IPC identifier for the object). A shared memory object is only removed after all currently attached pro‐ Two syntax styles are supported. The old Linux historical syntax specifies a three-letter keyword indi‐ % ptx - produce a permuted index of file contents ptx [OPTION]... [INPUT]... (without -G) ptx -G [OPTION]... [INPUT [OUTPUT]] Output a permuted index, including context, of the words in the input files. With no FILE, or when FILE is -, read standard input. Mandatory arguments to long options are mandatory for short options too. -A, --auto-reference output automatically generated references -G, --traditional % awk — pattern scanning and processing language awk [−F sepstring] [−v assignment]... program [argument...] awk [−F sepstring] −f progfile [−f progfile]... [−v assignment]... [argument...] The awk utility shall execute programs written in the awk programming language, which is specialized for textual data manipulation. An awk program is a sequence of patterns and corresponding actions. When input is read that matches a pattern, the action associated with that pattern is carried out. % ln - make links between files ate hard links by default, symbolic links with --symbolic. By default, each destination (name of new link) should not already exist. When creating hard links, each TARGET must exist. Symbolic links can hold arbitrary text; if later resolved, a relative link is interpreted in relation to its parent direc‐ tory. Mandatory arguments to long options are mandatory for short options too. % dbus-test-tool - D-Bus traffic generator and test tool --empty] [--payload=S | --stdin | --message-stdin | --random-size] dbus-test-tool is a multi-purpose tool for debugging and profiling D-Bus. dbus-test-tool black-hole connects to D-Bus, optionally requests a name, then does not reply to messages. It normally reads and discards messages from its D-Bus socket, but can be configured to sleep forever without reading. % switch_root - switch to another filesystem as the root of the mount tree switch_root [-hV] switch_root newroot init [arg...] switch_root moves already mounted /proc, /dev, /sys and /run to newroot and makes newroot the new root filesystem and starts init process. WARNING: switch_root removes recursively all files and directories on the current root filesystem. -h, --help Display help text and exit. % isc-config.sh - Get information about the installed version of ISC BIND isc-config.sh [--cflags] [--exec-prefix] [--libs] [--prefix] [--version] [libraries...] isc-config.sh prints information related to the installed version of ISC BIND, such as the compiler and linker flags required to compile and link programs that use ISC BIND libraries. The optional libraries are used to report specific details for compiling and linking for the listed listed on the command line. (Some libraries require other libraries, so are implied.) --cflags Prints the compiler command line options required to compile files that use ISC BIND. Use the libraries command line argument(s) to print additional specific flags to pass to the C compiler. % xfs_bmap - print block mapping for an XFS file xfs_bmap [ -adlpv ] [ -n num_extents ] file xfs_bmap -V xfs_bmap prints the map of disk blocks used by files in an XFS filesystem. The map lists each extent used by the file, as well as regions in the file that do not have any corresponding blocks (holes). Each line of the listings takes the following form: extent: [startoffset..endoffset]: startblock..endblock Holes are marked by replacing the startblock..endblock with hole. All the file offsets and disk blocks % c99 — compile standard C programs c99 [options...] pathname [[pathname] [−I directory] [−L directory] [−l library]]... The c99 utility is an interface to the standard C compilation system; it shall accept source code con‐ forming to the ISO C standard. The system conceptually consists of a compiler and link editor. The input files referenced by pathname operands and −l option-arguments shall be compiled and linked to produce an executable file. (It is unspecified whether the linking occurs entirely within the operation of c99; some % lvmconfig, lvm dumpconfig, lvm config — Display LVM configuration lvmconfig [-f|--file Filename] [--type {current|default|diff|full|list|missing|new|profilable|profilable- command|profilable-metadata}] [--atversion Version] [--sinceversion Version] [--ignoreadvanced] [--ignoreunsupported] [--ignorelocal] [-l|--list] [--config ConfigurationString] [--commandprofile Pro‐ [--showunsupported] [--validate] [--withsummary] [--withcomments] [--withspaces] [--withversions] [Con‐ figurationNode...] lvmconfig produces formatted output from the LVM configuration tree. The command was added in release -f, --file Filename Send output to a file named 'filename'. % ntp-wait - Wait for ntpd to stabilize the system clock ntp-wait [-flags] [-flag [value]] [--option-name[[=| ]value]] All arguments must be options. the boot sequence until after ntpd -g has set the time. -n number, --tries=number % mtr - a network diagnostic tool [--raw] [--csv] [--json] [--split] [--no-dns] [--show-ips] [-o FIELDS] [-y IPINFO] [--aslookup] [-i INTERVAL] [-c COUNT] [-s PACKETSIZE] [-B BITPATTERN] [-G GRACEPERIOD] [-Q TOS] [--mpls] [-a ADDRESS] [-f FIRST-TTL] [-m MAX-TTL] [-U MAX-UNKNOWN] [--udp] [--tcp] [-P PORT] [-L LOCALPORT] [-Z TIMEOUT] mtr combines the functionality of the traceroute and ping programs in a single network diagnostic tool. ing packets with purposely low TTLs. It continues to send packets with low TTL, noting the response time a bad (or simply overloaded) link. % runcon - run command with specified security context by one or more of LEVEL, ROLE, TYPE, and USER. If none of -c, -t, -u, -r, or -l, is specified, the first argument is used as the complete context. Any rent security context. % reiserfstune - The tunning tool for the ReiserFS filesystem. reiserfstune [ -f ] [ -h | --help ] [ -j | --journal-device FILE ] [ --no-journal-available ] [ --jour‐ nal-new-device FILE ] [ --make-journal-standard ] [ -s | --journal-new-size N ] [ -o | --journal-new-off‐ set N ] [ -t | --max-transaction-size N ] [ -b | --add-badblocks file ] [ -B | --badblocks file ] [ -u | --uuid UUID ] [ -l | --label LABEL ] [ -c | --check-interval interval-in-days ] [ -C | --time-last- checked timestamp ] [ -m | --max-mnt-count count ] [ -M | --mnt-count count ] device reiserfstune is used for tuning the ReiserFS. It can change two journal parameters (the journal size and the maximum transaction size), and it can move the journal's location to a new specified block device. the relocated journal was implemented for a special release of ReiserFS, and was not expected to be put you must apply a special patch. Without this patch the kernel will refuse to mount the newly modified % With no FILE, or when FILE is -, read standard input. -b, --binary read in binary mode -c, --check --tag create a BSD-style checksum % psfstriptable - remove the embedded Unicode character table from a console font psfstriptable fontfile outfile psfstriptable reads a .psf format console font from fontfile, removes the embedded Unicode font table if there is one, and writes the result to outfile. An input file name of "-" denotes standard input, and an output file name of "-" denotes standard output. % btrfs-convert [options] Warning The conversion utilizes free space of the original filesystem. The exact estimate of the required space cannot be foretold. The final btrfs metadata might occupy several gigabytes on a hundreds-gigabyte filesystem. % The options -v and --version print the version information of the program to standard output and exit. The options -h and --help print a usage information of the program to standard output and stop the pro‐ gram instantly. All other options are assumed to be groffer options. They are internally passed to groffer. They over‐ ride the behavior of the program. The options are optional, they can be omitted. The filespec arguments correspond to the filespec arguments of groffer. So they are either the names of % kvno - print key version numbers of Kerberos principals kvno acquires a service ticket for the specified Kerberos principals and prints out the key version num‐ bers of each. -c ccache Specifies the name of a credentials cache to use (if not the default) -e etype Specifies the enctype which will be requested for the session key of all the services named on the % strfile - create a random access file for storing strings unstr - dump strings in pointer order strfile [-iorsx] [-c char] sourcefile [outputfile] unstr [-c char] datafile[.ext] [outputfile] strfile reads a file containing groups of lines separated by a line containing a single percent `%' sign (or other specified delimiter character) and creates a data file which contains a header structure and a The output file, if not specified on the command line, is named sourcefile.dat. The purpose of unstr is to undo the work of strfile. It prints out the strings contained in the source‐ file, which is datafile.ext without its extension, or datafile if no extension is specified (in this % msgcmp - compare message catalog and template msgcmp [OPTION] def.po ref.pot Compare two Uniforum style .po files to check that both contain the same set of msgid strings. The def.po file is an existing PO file with the translations. The ref.pot file is the last created PO file, lated each and every message in your program. Where an exact match cannot be found, fuzzy matching is used to produce better diagnostics. Mandatory arguments to long options are mandatory for short options too. Input file location: def.po translations % anacron - runs commands periodically anacron [-s] [-f] [-n] [-d] [-q] [-t anacrontab] [-S spooldir] [job] anacron [-S spooldir] -u [-t anacrontab] [job] anacron [-V|-h] anacron -T [-t anacrontab] does not assume that the machine is running continuously. Hence, it can be used on machines that are not contains the list of jobs that Anacron controls. Each job entry specifies a period in days, a delay in minutes, a unique job identifier, and a shell command. % cut - remove sections from each line of files cut OPTION... [FILE]... Print selected parts of lines from each FILE to standard output. With no FILE, or when FILE is -, read standard input. Mandatory arguments to long options are mandatory for short options too. -b, --bytes=LIST select only these bytes -c, --characters=LIST select only these characters % pactree - package dependency tree viewer pactree [options] package Pactree produces a dependency tree for a package. By default, a tree-like output is generated, but with the --graph option, a Graphviz description is generated. -a, --ascii Use ASCII characters for tree formatting. By default, pactree will use Unicode line drawing characters if it is able to detect that the locale supports them. -b, --dbpath % zic - timezone compiler zic [ -v ] [ -d directory ] [ -l localtime ] [ -p posixrules ] [ -L leapsecondfilename ] [ -s ] [ -y com‐ mand ] [ filename ... ] Zic reads text from the file(s) named on the command line and creates the time conversion information files specified in this input. If a filename is -, the standard input is read. These options are available: -d directory Create time conversion information files in the named directory rather than in the standard direc‐ tory named below. -l timezone % sfdisk - display or manipulate a disk partition table sfdisk [options] device [-N partition-number] sfdisk [options] command sfdisk is a script-oriented tool for partitioning any block device. functionality for CHS (Cylinder-Head-Sector) addressing. CHS has never been important for Linux, and this addressing concept does not make any sense for new devices. tive sizes are specified, or when the default values are used. % groupmod - modify a group definition on the system groupmod [options] GROUP The groupmod command modifies the definition of the specified GROUP by modifying the appropriate entry in the group database. The options which apply to the groupmod command are: -g, --gid GID The group ID of the given GROUP will be changed to GID. option is used. % lessecho - expand metacharacters lessecho [-ox] [-cx] [-pn] [-dn] [-mx] [-nn] [-ex] [-a] file ... lessecho is a program that simply echos its arguments on standard output. But any metacharacter in the output is preceded by an "escape" character, which by default is a backslash. A summary of options is included below. -ex Specifies "x", rather than backslash, to be the escape char for metachars. If x is "-", no escape char is used and arguments containing metachars are surrounded by quotes instead. -ox Specifies "x", rather than double-quote, to be the open quote character, which is used if the -e- option is specified. % mcookie - generate magic cookies for xauth mcookie [options] usage: xauth add :0 . `mcookie` the sources /dev/urandom, /dev/random, or the libc pseudo-random functions, in this preference order. -f, --file file Use this file as an additional source of randomness. When file is '-', characters are read from % haveged - Generate random numbers and feed linux random device. haveged [options] haveged generates an unpredictable stream of random numbers harvested from the indirect effects of hard‐ ware events on hidden processor state (caches, branch predictors, memory translation tables, etc) using the HAVEGE (HArdware Volatile Entropy Gathering and Expansion) algorithm. The algorithm operates in user space, no special privilege is required for file system access to the output stream. Linux pools randomness for distribution by the /dev/random and /dev/urandom device interfaces. The stan‐ fill the /dev/random pool whenever the supply of random bits in /dev/random falls below the low water mark of the device. % pluginviewer - list loadable SASL plugins and their properties pluginviewer [-a] [-s] [-c] [-b min=N,max=N] [-e ssf=N,id=ID] [-m MECHS] [-x AUXPROP_MECH] [-f FLAGS] [-p PATH] pluginviewer can be used by a server administrator to troubleshoot SASL installations. The utility can list loadable (properly configured) client and server side plugins, as well as auxprop plugins. -a List auxprop plugins. -s List server authentication (SASL) plugins. -c List client authentication (SASL) plugins. % date - print or set the system date and time date [OPTION]... [+FORMAT] date [-u|--utc|--universal] [MMDDhhmm[[CC]YY][.ss]] Display the current time in the given FORMAT, or set the system date. Mandatory arguments to long options are mandatory for short options too. -d, --date=STRING display time described by STRING, not 'now' -f, --file=DATEFILE like --date; once for each line of DATEFILE % uuidgen - create a new UUID value uuidgen [options] library. The new UUID can reasonably be considered unique among all UUIDs created on the local system, and among UUIDs created on other systems in the past and in the future. There are two types of UUIDs which uuidgen can generate: time-based UUIDs and random-based UUIDs. By default uuidgen will generate a random-based UUID if a high-quality random number generator is present. Otherwise, it will choose a time-based UUID. It is possible to force the generation of one of these two UUID types by using the -r or -t options. -r, --random % glib-mkenums - C language enum description generation utility glib-mkenums [OPTION...] [FILE...] glib-mkenums is a small perl-script utility that parses C code to extract enum definitions and produces enum descriptions based on text templates specified by the user. Most frequently this script is used to produce C code that contains enum values as strings so programs can provide value name strings for introspection. glib-mkenums takes a list of valid C code files as input. The options specified control the text that is output, certain substitutions are performed on the text templates for keywords enclosed in @ characters. Production text substitutions Certain keywords enclosed in @ characters will be substituted in the emitted text. For the substitution examples of the keywords below, the following example enum definition is assumed: % deallocvt - deallocate unused virtual consoles deallocvt [N ...] The command deallocvt deallocates kernel memory and data structures for all unused virtual consoles. If one or more arguments N ... are given, only the corresponding consoles /dev/ttyN are deallocated. A virtual console is unused if it is not the foreground console, and no process has it open for reading or writing, and no text has been selected on its screen. % ssh-agent — authentication agent ssh-agent [-c | -s] [-Dd] [-a bind_address] [-E fingerprint_hash] [-t life] [command [arg ...]] ssh-agent [-c | -s] -k ssh-agent is usually started in the beginning of an X-session or a login session, and all other windows or programs are started as clients to the ssh-agent program. Through use of environment variables the agent to query the keys that are held in one. % sum - checksum and count the blocks in a file sum [OPTION]... [FILE]... Print checksum and block counts for each FILE. With no FILE, or when FILE is -, read standard input. -s, --sysv --help display this help and exit % cryptsetup-reencrypt - tool for offline LUKS device re-encryption cryptsetup-reencrypt Cryptsetup-reencrypt can be used to change reencryption parameters which otherwise require full on-disk data change (re-encryption). You can regenerate volume key (the real key used in on-disk encryption unclocked by passphrase), cipher, cipher mode. Cryptsetup-reencrypt reencrypts data on LUKS device in-place. During reencryption process the LUKS device is marked unavailable. WARNING: The cryptsetup-reencrypt program is not resistant to hardware or kernel failures during reen‐ % msgconv - character set conversion for message catalog msgconv [OPTION] [INPUTFILE] Converts a translation catalog to a different character encoding. Mandatory arguments to long options are mandatory for short options too. Input file location: INPUTFILE input PO file -D, --directory=DIRECTORY add DIRECTORY to list for input files search % partprobe - inform the OS of partition table changes partprobe [-d] [-s] [devices...] partprobe is a program that informs the operating system kernel of partition table changes. -d, --dry-run Don't update the kernel. -s, --summary % loginctl - Control the systemd login manager The following options are understood: --no-ask-password Do not query the user for authentication for privileged operations. -p, --property= When showing session/user/seat properties, limit display to certain properties as specified as % halt, poweroff, reboot - Halt, power-off or reboot the machine The following options are understood: --help Print a short help text and exit. % sntp - standard Simple Network Time Protocol client program sntp [-flags] [-flag [value]] [--option-name[[=| ]value]] [ hostname-or-IP ...] sntp can be used as an SNTP client to query a NTP or SNTP server and either display the time or set the local system's time (given suitable privilege). It can be run as an interactive command or from a cron job. NTP (the Network Time Protocol) and SNTP (the Simple Network Time Protocol) are defined and The default is to write the estimated correct local date and time (i.e. not UTC) to the standard output % xzcmp, xzdiff, lzcmp, lzdiff - compare compressed files from which the compression format suffix has been stripped. If two files are specified, then they are served. The names lzcmp and lzdiff are provided for backward compatibility with LZMA Utils. % ngettext - translate message and choose plural form ngettext [OPTION] [TEXTDOMAIN] MSGID MSGID-PLURAL COUNT The ngettext program translates a natural language message into the user's language, by looking up the translation in a message catalog, and chooses the appropriate plural form, which depends on the number COUNT and the language of the message catalog where the translation was found. Display native language translation of a textual message whose grammatical form depends on a number. -d, --domain=TEXTDOMAIN retrieve translated message from TEXTDOMAIN -e enable expansion of some escape sequences % lastlog - reports the most recent login of all users or of a given user lastlog [options] lastlog formats and prints the contents of the last login log /var/log/lastlog file. The login-name, port, and last login time will be printed. The default (no flags) causes lastlog entries to be printed, sorted by their order in /etc/passwd. The options which apply to the lastlog command are: -b, --before DAYS Print only lastlog records older than DAYS. -C, --clear % lvresize — resize a logical volume [-I|--stripesize StripeSize]] {-l|--extents [+|-]LogicalExtentsNumber[%{VG|LV|PVS|FREE|ORIGIN}] | -L|--size [+|-]LogicalVolumeSize[bBsSkKmMgGtTpPeE]} [--poolmetadatasize [+]MetadataVolumeSize[bBsSkKm‐ [PhysicalVolumePath[:PE[-PE]]...] lvresize allows you to resize a logical volume. Be careful when reducing a logical volume's size, because data in the reduced part is lost!!! You should therefore ensure that any filesystem on the vol‐ ume is shrunk first so that the extents that are to be removed are not in use. Resizing snapshot logical % keyctl - Key management facility control keyctl --version keyctl show [-x] [] keyctl add keyctl padd keyctl request [] keyctl update keyctl pupdate keyctl newring keyctl revoke keyctl clear keyctl link keyctl unlink [] % capsh - capability shell wrapper capsh [OPTION]... handy wrapper for certain types of capability testing and environment creation. It also provides some debugging features useful for summarizing capability state. The tool takes a number of optional arguments, acting on them in the order they are provided. They are as follows: --print Display prevailing capability and related state. % systemd-firstboot, systemd-firstboot.service - Initialize basic system settings on or before the first boot-up of a system systemd-firstboot.service systemd-firstboot initializes the most basic system settings interactively on the first boot, or · The system locale, more specifically the two locale variables LANG= and LC_MESSAGES · The system time zone · The system host name % gettextize - install or upgrade gettext infrastructure gettextize [OPTION]... [package-dir] Prepares a source package to use gettext. --help print this help and exit --version print version information and exit -f, --force force writing of new files even if old exist % lt-recode [OPTION]... [ [CHARSET] | REQUEST [FILE]... ] Free `recode' converts files between various character sets and surfaces. If a long option shows an argument as mandatory, then it is mandatory for the equivalent short option also. Similarly for optional arguments. Listings: -l, --list[=FORMAT] list one or all known charsets and aliases -k, --known=PAIRS restrict charsets according to known PAIRS list % elfedit - Update the ELF header of ELF files. elfedit [--input-mach=machine] [--input-type=type] [--input-osabi=osabi] --output-mach=machine --output-type=type --output-osabi=osabi [-v|--version] [-h|--help] elffile... elfedit updates the ELF header of ELF files which have the matching ELF machine and file types. The options control how and which fields in the ELF header should be updated. % grub-fstest - debug tool for GRUB filesystem drivers Debug tool for filesystem driver. Commands: blocklist FILE Display blocklist of FILE. cat FILE Copy FILE to standard output. cmp FILE LOCAL % grep, egrep, fgrep - print lines matching a pattern grep searches the named input FILEs for lines containing a match to the given PATTERN. If no files are specified, or if the file “-” is given, grep searches standard input. By default, grep prints the matching lines. In addition, the variant programs egrep and fgrep are the same as grep -E and grep -F, respectively. These variants are deprecated, but are provided for backward compatibility. Generic Program Information --help Output a usage message and exit. % ldns-config - show compiler and linker flags for ldns usage. When writing programs using ldns, you have to tell the compiler where to look for include files and what libraries from which location to link to. ldns-config can be used to find out what flags to use with the C compiler and the linker. --cflags Show the C compiler flags needed to compile with ldns --libs Show the flags to be used to link with ldns --version % pmap - report memory map of a process pmap [options] pid [...] The pmap command reports the memory map of a process or processes. -x, --extended Show the extended format. -d, --device Show the device format. -q, --quiet Do not display some header or footer lines. % The options -v and --version print the version information of the program to standard output and exit. The options -h and --help print a usage information of the program to standard output and stop the pro‐ gram instantly. All other options are assumed to be groffer options. They are internally passed to groffer. They over‐ ride the behavior of the program. The options are optional, they can be omitted. The filespec arguments correspond to the filespec arguments of groffer. So they are either the names of % dnssec-keymgr - Ensures correct DNSKEY coverage for a zone based on a defined policy dnssec-keymgr [-K directory] [-c file] [-f] [-k] [-q] [-v] [-z] [-g path] [-r path] [-s path] [zone...] dnssec-keymgr is a high level Python wrapper to facilitate the key rollover process for zones handled by BIND. It uses the BIND commands for manipulating DNSSEC key metadata: dnssec-keygen and dnssec-settime. DNSSEC policy can be read from a configuration file (default /etc/dnssec-policy.conf), from which the key parameters, publication and rollover schedule, and desired coverage duration for any given zone can be default policy used for all zones. When dnssec-keymgr runs, it examines the DNSSEC keys for one or more zones, comparing their timing metadata against the policies for those zones. If key settings do not conform to the DNSSEC policy (for example, because the policy has been changed), they are automatically corrected. % apropos - search the manual page names and descriptions apropos [-dalv?V] [-e|-w|-r] [-s list] [-m system[,...]] [-M path] [-L locale] [-C file] keyword ... Each manual page has a short description available within it. apropos searches the descriptions for instances of keyword. cial characters to stop the shell from interpreting them. The standard matching rules allow matches to be made against the page name and word boundaries in the description. The database searched by apropos is updated by the mandb program. Depending on your installation, this % dbus-binding-tool - C language GLib bindings generation utility. dbus-binding-tool [--force] [--help] [--ignore-unsupported] [--mode=pretty|glib-client|glib-server] [--output=file] [--prefix=symbol-prefix] [--version] [file...] dbus-binding-tool is used to expose a GObject via D-Bus. As input, dbus-binding-tool uses a D-Bus Intro‐ header file which eases the use of a remote D-Bus object. Output is sent to standard out or to the file‐ name specified with the --output argument. The following is a sample D-Bus Introspection XML file which describes an object that exposes one method, named ManyArgs: % readprofile - read kernel profiling information readprofile [options] The readprofile command uses the /proc/profile information to print ascii data on standard output. The output is organized in three columns: the first is the number of clock ticks, the second is the name of the C function in the kernel where those many ticks occurred, and the third is the normalized `load' of the procedure, calculated as a ratio between the number of ticks and the length of the procedure. The output is filled with blanks to ease readability. -a, --all % rsync - a fast, versatile, remote (and local) file-copying tool Access via remote shell: Pull: rsync [OPTION...] [USER@]HOST:SRC... [DEST] Push: rsync [OPTION...] SRC... [USER@]HOST:DEST Access via rsync daemon: Pull: rsync [OPTION...] [USER@]HOST::SRC... [DEST] rsync [OPTION...] rsync://[USER@]HOST[:PORT]/SRC... [DEST] Push: rsync [OPTION...] SRC... [USER@]HOST::DEST rsync [OPTION...] SRC... rsync://[USER@]HOST[:PORT]/DEST % clockdiff - measure clock difference between hosts -o Use IP TIMESTAMP with ICMP ECHO instead of ICMP TIMESTAMP messages. It is useful with some desti‐ dresses instead of four term one. What flavor works better depends on target host. Particularly, -o is better for Linux. % vgscan — scan all disks for volume groups and rebuild caches [--notifydbus] [-P|--partial] [--reportformat {basic|json}] [-v|--verbose] vgscan scans all SCSI, (E)IDE disks, multiple devices and a bunch of other disk devices in the system to avoid a CD ROM, for example. hardware. % delv - DNS lookup and validation utility [-q name] [-t type] [-x addr] [name] [type] [class] [queryopt...] delv [-h] delv [-v] delv [queryopt...] [query...] delv (Domain Entity Lookup & Validation) is a tool for sending DNS queries and validating the results, using the same internal resolver and validator logic as named. delv will send to a specified name server all queries needed to fetch and validate the requested data; % pscap - a program to see capabilities pscap [ -a ] pscap is a program that prints out a report of process capabilities. If the application has any capabili‐ ties, it will be in the report with the exception of init. By giving the -a command line option, init will be included, too. If a process is not in the report, it has dropped all capabilities. If the process has partial capabilities, it is further examined to see if it has an open-ended bounding set. If this is found to be true, a '+' symbol is added. Steve Grubb % dirname - strip last component from file name output '.' (meaning the current directory). -z, --zero end each output line with NUL, not newline --help display this help and exit --version output version information and exit % zcmp, zdiff - compare compressed files Zcmp and zdiff are used to invoke the cmp or the diff program on files compressed via gzip. All options fed to cmp or diff. The input files are not modified. The exit status from cmp or diff is preserved. BUGS % named-journalprint - print zone journal in human-readable form named-journalprint {journal} named-journalprint prints the contents of a zone journal file in a human-readable form. Journal files are automatically created by named when changes are made to dynamic zones (e.g., by nsupdate). They record each addition or deletion of a resource record, in binary format, allowing the changes to be re-applied to the zone when the server is restarted after a shutdown or crash. By default, the name of the journal file is formed by appending the extension .jnl to the name of the corresponding zone file. named-journalprint converts the contents of a given journal file into a human-readable text format. Each line begins with "add" or "del", to indicate whether the record was added or deleted, and continues with the resource record in master-file format. % debugreiserfs - The debugging tool for the ReiserFS filesystem. device debugreiserfs sometimes helps to solve problems with reiserfs filesystems. When run without options it prints the super block of the ReiserFS filesystem found on the device. device is the special file corresponding to the device (e.g /dev/hdXX for an IDE disk partition or /dev/sdXX for a SCSI disk partition). -j device prints the contents of the journal. The option -p allows it to pack the journal with other meta‐ % thin_metadata_size - thin provisioning metadata device/file size calculator. thin_metadata_size [options] thin_metadata_size calculates the size of the thin provisioning metadata based on the block size of the thin provisioned devices, the size of the thin provisioning pool and the maximum number of all thin pri‐ sioned devices and snapshots. Because thin provisioning pools are holding widely variable contents, this tool is needed to provide sensible initial default size. -b, --block-size BLOCKSIZE[bskKmMgGtTpPeEzZyY] Block size of thin provisioned devices in units of bytes, sectors, kibibytes, kilobytes, ... respectively. Default is in sectors without a block size unit specifier. Size/number option % findmnt - find a filesystem findmnt [options] findmnt [options] device|mountpoint findmnt [options] [--source] device [--target|--mountpoint] mountpoint findmnt will list all mounted filesytems or search for a filesystem. The findmnt command is able to search in /etc/fstab, /etc/mtab or /proc/self/mountinfo. If device or mountpoint is not given, all filesystems are shown. mountpoint (and vice versa) if the --target, --mountpoint or --source options are not specified. % The options -v and --version print the version information of the program to standard output and exit. The options -h and --help print a usage information of the program to standard output and stop the pro‐ gram instantly. All other options are assumed to be groffer options. They are internally passed to groffer. They over‐ ride the behavior of the program. The options are optional, they can be omitted. The filespec arguments correspond to the filespec arguments of groffer. So they are either the names of % last, lastb - show a listing of last logged in users last [options] [username...] [tty...] lastb [options] [username...] [tty...] last searches back through the /var/log/wtmp file (or the file designated by the -f option) and displays a list of all users logged in (and out) since that file was created. One or more usernames and/or ttys be abbreviated, thus last 0 is the same as last tty0. When catching a SIGINT signal (generated by the interrupt key, usually control-C) or a SIGQUIT signal, terminate. The pseudo user reboot logs in each time the system is rebooted. Thus last reboot will show a log of all % ethtool - query or control network driver and hardware settings ethtool devname ethtool -h|--help ethtool --version ethtool -a|--show-pause devname ethtool -A|--pause devname [autoneg on|off] [rx on|off] [tx on|off] ethtool -c|--show-coalesce devname ethtool -C|--coalesce devname [adaptive-rx on|off] [adaptive-tx on|off] [rx-usecs N] [rx-frames N] [rx-usecs-irq N] [rx-frames-irq N] [tx-usecs N] [tx-frames N] [tx-usecs-irq N] [tx-frames-irq N] % groupmems - administer members of a user's primary group groupmems -a user_name | -d user_name | [-g group_name] | -l | -p The groupmems command allows a user to administer his/her own group membership list without the requirement of superuser privileges. The groupmems utility is for systems that configure its users to be in their own name sake primary group (i.e., guest / guest). Only the superuser, as administrator, can use groupmems to alter the memberships of other groups. The options which apply to the groupmems command are: -a, --add user_name Add a user to the group membership list. % decoded structures. -b, --benchmark perform a benchmark on decoding -s, --strict use strict DER decoding -h, --help display this help and exit % mkfs.xfs - construct an XFS filesystem mkfs.xfs [ -b block_size ] [ -m global_metadata_options ] [ -d data_section_options ] [ -f ] [ -i inode_options ] [ -l log_section_options ] [ -n naming_options ] [ -p protofile ] [ -q ] [ -r real‐ time_section_options ] [ -s sector_size ] [ -L label ] [ -N ] [ -K ] device mkfs.xfs -V mkfs.xfs constructs an XFS filesystem by writing on a special file using the values found in the argu‐ In its simplest (and most commonly used form), the size of the filesystem is determined from the disk driver. As an example, to make a filesystem with an internal log on the first partition on the first SCSI disk, use: % new_inode_size ] [ -j ] [ -J journal-options ] [ -m reserved-blocks-percentage ] [ -o [^]mount- options[,...] ] [ -p mmp_update_interval ] [ -r reserved-blocks-count ] [ -s sparse-super-flag ] [ -u user ] [ -g group ] [ -C mount-count ] [ -E extended-options ] [ -L volume-name ] [ -M last-mounted- directory ] [ -O [^]feature[,...] ] [ -Q quota-options ] [ -T time-last-checked ] [ -U UUID ] [ -z undo_file ] device % lsusb - list USB devices lsusb [ options ] lsusb is a utility for displaying information about USB buses in the system and the devices connected to them. -v, --verbose configuration descriptors for the device's current speed. Class descriptors will be shown, when available, for USB device classes including hub, audio, HID, communications, and chipcard. -s [[bus]:][devnum] % cpio — copy files to and from archives cpio -i [options] [pattern ...] [< archive] cpio -o [options] < name-list [> archive] cpio -p [options] dest-dir < name-list zip, jar, ar, and ISO 9660 cdrom images and can create tar, pax, cpio, ar, and shar archives. The first option to cpio is a mode indicator from the following list: -i Input. Read an archive from standard input (unless overridden) and extract the contents to disk or (if the -t option is specified) list the contents to standard output. If one or more file patterns are specified, only files matching one of the patterns will be extracted. -o Output. Read a list of filenames from standard input and produce a new archive on standard output (unless overridden) containing the specified items. % systemd, init - systemd system and service manager systemd is a system and service manager for Linux operating systems. When run as first process on boot telinit and pass all command line arguments unmodified. That means init and telinit are mostly equivalent When run as a system instance, systemd interprets the configuration file system.conf and the files in system.conf.d directories; when run as a user instance, systemd interprets the configuration file % nstat, rtacct - network statistics tools. nstat and rtacct are simple tools to monitor kernel snmp counters and network interface statistics. -h, --help Print help -V, --version Print version -z, --zero Dump zero counters too. By default they are not shown. % autoscan - Generate a preliminary configure.in autoscan [OPTION]... [SRCDIR] Examine source files in the directory tree rooted at SRCDIR, or the current directory if none is given. Search the source files for common portability problems, check for incompleteness of `configure.ac', and create a file `configure.scan' which is a preliminary `configure.ac' for that package. -h, --help print this help, then exit -V, --version print version number, then exit -v, --verbose % vgchange — change attributes of a volume group vgchange [--addtag Tag] [--alloc AllocationPolicy] [-A|--autobackup {y|n}] [-a|--activate [a|e|s|l] {y|n}] [--activationmode {complete|degraded|partial}] [-K|--ignoreactivationskip] [--monitor {y|n}] Tag] [--detachprofile] [-h|--help] [--ignorelockingfailure] [--ignoremonitoring] [--ignoreskippedcluster] [--sysinit] [--noudevsync] [--lock-start] [--lock-stop] [--lock-type LockType] [-l|--logicalvolume Max‐ datacopies NumberOfCopies|unmanaged|all] [-P|--partial] [-s|--physicalextentsize PhysicalExtent‐ Size[bBsSkKmMgGtTpPeE]] [--reportformat {basic|json}] [-S|--select Selection] [--systemid SystemID] vgchange allows you to change the attributes of one or more volume groups. Its main purpose is to acti‐ groups are subject to changes and allow access to their logical volumes. [Not yet implemented: During % systemd-run - Run programs in transient scope or service or timer units If a command is run as transient service unit, it will be started and managed by the service manager like any other service, and thus shows up in the output of systemctl list-units like any other unit. It will run in a clean and detached execution environment, with the service manager as its parent process. In this mode, systemd-run will start the service asynchronously in the background and return after the command has begun execution. % netcat - GNU Netcat Manual netcat [options] hostname port [port] ... netcat -l -p port [options] [hostname] [port] ... netcat -L hostname:port -p port [options] ... Netcat is a simple Unix utility which reads and writes data across network connections, using TCP or UDP protocol. It is designed to be a reliable "back-end" tool that can be used directly or easily driven by other programs and scripts. At the same time, it is a feature-rich network debugging and exploration tool, since it can create almost any kind of connection you would need and has several interesting built- in capabilities. Netcat, or "nc" as the original program was named, should have been supplied long ago as another one of those cryptic but standard Unix tools. % telnet - User interface to TELNET telnet [OPTION...] [HOST [PORT]] Login to remote system HOST (optionally, on service port PORT) General options: -6, --ipv6 use only IPv6 % If the output filename is present, the output is written there. If it is - or absent the output is writ‐ ten to the standard output. the BUGS section below. % grub-mkconfig - generate a GRUB configuration file grub-mkconfig [OPTION] Generate a grub config file -o, --output=FILE output generated config to FILE [default=stdout] -h, --help print this message and exit -v, --version print the version information and exit % arpd - userspace arp daemon. rate ] [ ] The arpd daemon collects gratuitous ARP information, saving it on local disk and feeding it to the kernel on demand to avoid redundant broadcasting due to limited size of the kernel ARP cache. -h -? Print help -l Dump the arpd database to stdout and exit. The output consists of three columns: the interface index, the IP address of the interface, and the MAC address of the interface. Negative entries for a colon and the most recent time when the fact that the host is dead was proven. % soelim - interpret .so requests in groff input soelim [-Crtv] [-I dir] [files ...] It is possible to have whitespace between the -I command line option and its parameter. soelim reads files and replaces lines of the form .so file by the contents of file. It is useful if files included with .so need to be preprocessed. Normally, soelim should be invoked with the -s option of groff. To embed ‘\’ in the file name, write ‘\\’ or ‘\e’. To embed a space, write ‘\ ’. Any other escape sequence in file makes soelim ignore the whole line. % gpg-error-config - Script to get information about the installed version of libgpg-error gpg-error-config [options] gpg-error-config is a tool that is used to configure to determine the compiler and linker flags that macros for GNU autoconf that are included with Libgpg-error. gpg-error-config accepts the following options: --mt Provide output appropriate for multithreaded programs. --mt is only useful when combined with other options, and must be the first option if present. --version % autoupdate - Update a configure.in to a newer Autoconf autoupdate [OPTION]... [TEMPLATE-FILE]... Update each TEMPLATE-FILE if given, or `configure.ac' if present, or else `configure.in', to the syntax of the current version of Autoconf. The original files are backed up. Operation modes: -h, --help print this help, then exit -V, --version print version number, then exit -v, --verbose % ldns-verify-zone - read a DNSSEC signed zone and verify it. ldns-verify-zone ZONEFILE ldns-verify-zone reads a DNS zone file and verifies it. RRSIG resource records are checked against the DNSKEY set at the zone apex. -h Show usage and exit -a Apex only, check only the zone apex % xz, unxz, xzcat, lzma, unlzma, lzcat - Compress or decompress .xz and .lzma files xz [option...] [file...] unxz is equivalent to xz --decompress. xzcat is equivalent to xz --decompress --stdout. lzma is equivalent to xz --format=lzma. unlzma is equivalent to xz --format=lzma --decompress. lzcat is equivalent to xz --format=lzma --decompress --stdout. When writing scripts that need to decompress files, it is recommended to always use the name xz with appropriate arguments (xz -d or xz -dc) instead of the names unxz and xzcat. % info - read Info documents info [OPTION]... [MENU-ITEM...] Read documentation in Info format. -a, --all use all matching manuals. -k, --apropos=STRING look up STRING in all indices of all manuals. -d, --directory=DIR add DIR to INFOPATH. % netstat - Print network connections, routing tables, interface statistics, masquerade connections, and multicast memberships [--rfcomm|-f] [--listening|-l] [--all|-a] [--numeric|-n] [--numeric-hosts] [--numeric-ports] [--numeric-users] [--symbolic|-N] [--extend|-e[--extend|-e]] [--timers|-o] [--program|-p] [--verbose|-v] [--continuous|-c] [--wide|-W] netstat {--route|-r} [address_family_options] [--extend|-e[--extend|-e]] [--verbose|-v] [--numeric|-n] [--numeric-hosts] [--numeric-ports] [--numeric-users] [--continuous|-c] netstat {--interfaces|-i} [--all|-a] [--extend|-e[--extend|-e]] [--verbose|-v] [--program|-p] [--numeric|-n] [--numeric-hosts] [--numeric-ports] [--numeric-users] [--continuous|-c] netstat {--groups|-g} [--numeric|-n] [--numeric-hosts] [--numeric-ports] [--numeric-users] [--continu‐ ous|-c] % ldns-zcat - reunite (z)split up a zone files ldns-zcat zonefiles ldns-zcat will read in a bunch of (z)split up zonefiles and creates a new larger zone file. The SOA record in the first part is used as the SOA record in the generated zone. The resulted zone file is printed to standard output. -o ORIGIN use ORIGIN when reading in the zone -v show the version number and exit % chem - groff preprocessor for producing chemical structure diagrams chem [option ....] [--] [filespec ....] chem -h | --help chem -v | --version There are no other options than -h, --help, -v, and --version; these options provoke the printing of a version or usage information, respectively, and all filespec arguments are ignored. A filespec argument is either a file name of an existing file or a minus character -, meaning standard input. If no argument is specified then standard input is taken automatically. chem produces chemical structure diagrams. Today's version is best suited for organic chemistry (bonds, % seq - print a sequence of numbers seq [OPTION]... LAST seq [OPTION]... FIRST LAST seq [OPTION]... FIRST INCREMENT LAST Print numbers from FIRST to LAST, in steps of INCREMENT. Mandatory arguments to long options are mandatory for short options too. -f, --format=FORMAT use printf style floating-point FORMAT -s, --separator=STRING use STRING to separate numbers (default: \n) % groups - display current group names groups [user] The groups command displays the current group names or ID values. If the value does not have a corresponding entry in /etc/group, the value will be displayed as the numerical group value. The optional user parameter will display the groups for the named user. Systems which do not support concurrent group sets will have the information from /etc/group reported. The user must use newgrp or sg to change his current real and effective group ID. FILES /etc/group Group account information. % ifconfig - configure a network interface ifconfig [-v] [-a] [-s] [interface] ifconfig [-v] interface [aftype] options | address ... Ifconfig is used to configure the kernel-resident network interfaces. It is used at boot time to set up interfaces as necessary. After that, it is usually only needed when debugging or when system tuning is needed. If no arguments are given, ifconfig displays the status of the currently active interfaces. If a single interface argument is given, it displays the status of the given interface only; if a single -a argument is given, it displays the status of all interfaces, even those that are down. Otherwise, it configures an interface. Address Families % vgdisplay — display attributes of volume groups {basic|json}] [-s|--short] [-S|--select Selection] [-v|--verbose] [-d|--debug] [-h|--help] [--ignorelock‐ ingfailure] [--ignoreskippedcluster] [--nosuffix] [-P|--partial] [--units hHbBsSkKmMgGtTpPeE] [--version] [-d|--debug] [-h|-?|--help] [--ignorelockingfailure] [--ignoreskippedcluster] [--logonly] [--noheadings] [--nosuffix] [-P|--partial] [--reportformat {basic|json}] [--separator Separator] [--unbuffered] [--units with it's physical and logical volumes and their sizes etc. % dnssec-dsfromkey - DNSSEC DS RR generation tool [-A] [-v level] {dnsname} dnssec-dsfromkey [-h] [-V] % blocks-per-group ] [ -G number-of-groups ] [ -i bytes-per-inode ] [ -I inode-size ] [ -j ] [ -J journal- options ] [ -N number-of-inodes ] [ -n ] [ -m reserved-blocks-percentage ] [ -o creator-os ] [ -O [^]fea‐ ture[,...] ] [ -q ] [ -r fs-revision-level ] [ -E extended-options ] [ -v ] [ -F ] [ -L volume-label ] [ -M last-mounted-directory ] [ -S ] [ -t fs-type ] [ -T usage-type ] [ -U UUID ] [ -V ] [ -e errors-behav‐ ior ] [ -z undo_file ] device [ fs-size ] size ] by device. % ftpd - File Transfer Protocol server. ftpd [OPTION...] File Transfer Protocol daemon. -6, --ipv6 restrict daemon to IPv6 -a, --auth=AUTH use AUTH for authentication % col - filter reverse line feeds from input col [options] col filters out reverse (and half-reverse) line feeds so the output is in the correct order, with only forward and half-forward line feeds. It also replaces any whitespace characters with tabs where possi‐ col reads from standard input and writes to standard output. -b, --no-backspaces Do not output any backspaces, printing only the last character written to each column position. -f, --fine % unhide — forensic tool to find hidden processes unhide-posix proc | sys unhide is a forensic tool to find processes hidden by rootkits, Linux kernel modules or by other tech‐ niques. It detects hidden processes using six techniques. Options are only available for unhide-linux not for unhide-posix. -d Do a double check in brute test to avoid false positive. -f Write a log file (unhide-linux.log) in the current directory. % blocks-per-group ] [ -G number-of-groups ] [ -i bytes-per-inode ] [ -I inode-size ] [ -j ] [ -J journal- options ] [ -N number-of-inodes ] [ -n ] [ -m reserved-blocks-percentage ] [ -o creator-os ] [ -O [^]fea‐ ture[,...] ] [ -q ] [ -r fs-revision-level ] [ -E extended-options ] [ -v ] [ -F ] [ -L volume-label ] [ -M last-mounted-directory ] [ -S ] [ -t fs-type ] [ -T usage-type ] [ -U UUID ] [ -V ] [ -e errors-behav‐ ior ] [ -z undo_file ] device [ fs-size ] size ] by device. % route - show / manipulate the IP routing table [irtt I] [reject] [mod] [dyn] [reinstate] [[dev] If] route [-V] [--version] [-h] [--help] Route manipulates the kernel's IP routing tables. Its primary use is to set up static routes to specific When the add or del options are used, route modifies the routing tables. Without these options, route % setfont - load EGA/VGA console screen font setfont [-O font+umap.orig] [-o font.orig] [-om cmap.orig] [-ou umap.orig] [-N] [font.new ...] [-m cmap] [-u umap] [-C console] [-hH] [-v] [-V] The setfont command reads a font from the file font.new and loads it into the EGA/VGA character genera‐ tor, and optionally outputs the previous font. It can also load various mapping tables and output the previous versions. and load the union. Typical use: setfont Load a default font. % python - an interpreted, interactive, object-oriented programming language python [ -B ] [ -b ] [ -d ] [ -E ] [ -h ] [ -i ] [ -I ] [ -m module-name ] [ -q ] [ -O ] [ -OO ] [ -s ] [ -S ] [ -u ] [ -v ] [ -V ] [ -W argument ] [ -x ] [ [ -X option ] -? ] [ -c command | script | - ] [ arguments ] Python is an interpreted, interactive, object-oriented programming language that combines remarkable power with very clear syntax. For an introduction to programming in Python, see the Python Tutorial. The Python Library Reference documents built-in and standard types, constants, functions and modules. Finally, the Python Reference Manual describes the syntax and semantics of the core language in (perhaps installed on your system as well.) Python's basic power can be extended with your own modules written in C or C++. On most systems such % flock - manage locks from shell scripts flock [options] file|directory command [arguments] flock [options] file|directory -c command flock [options] number The first and second of the above forms wrap the lock around the execution of a command, in a manner sim‐ priate permissions) if it does not already exist. By default, if the lock cannot be immediately acquired, flock waits until the lock is available. The third form uses an open file by its file descriptor number. See the examples below for how that can be used. % With no FILE, or when FILE is -, read standard input. Mandatory arguments to long options are mandatory for short options too. -d, --decode decode data -i, --ignore-garbage when decoding, ignore non-alphabet characters % Mandatory arguments to long options are mandatory for short options too. -c, --check checks the syntax only -o, --output=FILE output file % infotocap - convert a terminfo description into a termcap description infotocap looks in each given text file for terminfo descriptions. For each terminfo description found, an equivalent termcap description is written to standard output. Terminfo use capabilities are trans‐ lated directly to termcap tc capabilities. -v print out tracing information on standard error as the program runs. -V print out the version of the program in use on standard error and exit. line to a maximum width of 60 characters. % setfattr - set extended attributes of filesystem objects setfattr [-h] -n name [-v value] pathname... setfattr [-h] -x name pathname... setfattr [-h] --restore=file The setfattr command associates a new value with an extended attribute name for each specified file. -n name, --name=name Specifies the name of the extended attribute to set. -v value, --value=value Specifies the new value of the extended attribute. There are three methods available for encoding the value. If the given string is enclosed in double quotes, the inner string is treated as text. In % kadmind [-x db_args] [-r realm] [-m] [-nofork] [-proponly] [-port port-number] [-P pid_file] [-p kadmind starts the Kerberos administration server. kadmind typically runs on the master Kerberos server, which stores the KDC database. If the KDC database uses the LDAP module, the administration server and the KDC server need not run on the same machine. kadmind accepts remote requests from programs such as kadmind requires a number of configuration files to be set up in order for it to work: The KDC configuration file contains configuration information for the KDC and admin servers. kad‐ mind uses settings in this file to locate the Kerberos database, and is also affected by the % btrfs-check - check or repair an unmounted btrfs filesystem btrfs check [options] The filesystem checker is used to verify structural integrity of a filesystem and attempt to repair it if requested. The filesystem must be unmounted. By default, btrfs check will not modify the device but you can reaffirm that by the option --readonly. btrfsck is an alias of btrfs check command and is now deprecated. Warning Do not use --repair unless you are advised to by a developer, an experienced user or accept the fact that fsck cannot possibly fix all sorts of damage that could happen to a filesystem because of software and hardware bugs. % lsinitcpio - Examine an initramfs lsinitcpio [action] [options] image Examines the contents of an initcpio image. Without any options, lsinitcpio simply lists the contents of an image. ACTIONS -a, --analyze Analyze the contents of the specified image and print output in human readable form. -c, --config Show the configuration file the given image was built with. -l, --list % eject - eject removable media eject [options] device|mountpoint eject allows removable media (typically a CD-ROM, floppy disk, tape, JAZ, ZIP or USB disk) to be ejected under software control. The command can also control some multi-disc CD-ROM changers, the auto-eject feature supported by some devices, and close the disc tray of some CD-ROM drives. The device corresponding to device or mountpoint is ejected. If no name is specified, the default name '/dev/sda'), UUID=uuid or LABEL=label tags. There are four different methods of ejecting, depending on whether the device is a CD-ROM, SCSI device, removable floppy, or tape. By default eject tries all four methods in order until it succeeds. % clear - clear the terminal screen clear bility is defined). clear looks in the environment for the terminal type and then in the terminfo data‐ base to determine how to clear the screen. % rsh - Remote shell client remote shell -6, --ipv6 use only IPv6 allows an eight-bit input data path at all times % crontab - maintains crontab files for individual users crontab [-u user] file crontab [-u user] [-l | -r | -e] [-i] [-s] crontab -n [ hostname ] crontab -c Crontab is the program used to install a crontab table file, remove or list the existing tables used to /var/spool/, they are not intended to be edited directly. For SELinux in MLS mode, you can define more In this version of Cron it is possible to use a network-mounted shared /var/spool/cron across a cluster of hosts and specify that only one of the hosts should run the crontab jobs in the particular directory % netctl-auto - Control automatic selection of wireless netctl profiles netctl-auto [--help | --version] netctl-auto@.service file. See netctl.special(7) for details about the service file. The following commands are understood: list List all profiles which are currently available for automatic selection. Active profiles will be marked with a ‘*’, disabled profiles will be marked with a ‘!’. % setfacl - set file access control lists setfacl [-bkndRLPvh] [{-m|-x} acl_spec] [{-M|-X} acl_file] file ... setfacl --restore=file of commands is followed by a sequence of files (which in turn can be followed by another sequence of com‐ mands, ...). The options -m, and -x expect an ACL on the command line. Multiple ACL entries are separated by comma characters (`,'). The options -M, and -X read an ACL from a file or from standard input. The ACL entry format is described in Section ACL ENTRIES. The --set and --set-file options set the ACL of a file or a directory. The previous ACL is replaced. ACL % mkreiserfs - The create tool for the Linux ReiserFS filesystem. mkreiserfs [ -dfV ] [ -b | --block-size N ] [ -h | --hash HASH ] [ -u | --uuid UUID ] [ -l | --label LABEL ] [ --format FORMAT ] [ -q | --quiet ] [ -j | --journal-device FILE ] [ -s | --journal-size N ] [ -o | --journal-offset N ] [ -t | --transaction-max-size N ] [ -B | --badblocks file ] device [ filesys‐ tem-size ] mkreiserfs creates a Linux ReiserFS filesystem on a device (usually a disk partition). device is the special file corresponding to a device or to a partition (e.g /dev/hdXX for an IDE disk partition or /dev/sdXX for a SCSI disk partition). filesystem-size is the size in blocks of the filesystem. If omitted, mkreiserfs will automatically set it. % jfs_debugfs - shell-type JFS file system editor jfs_debugfs device jfs_debugfs is a program which can be used to perform various low-level actions on a JFS formatted device. jfs_debugfs must be run as root. a[lter] replaces the data located at the of with % xz, unxz, xzcat, lzma, unlzma, lzcat - Compress or decompress .xz and .lzma files xz [option...] [file...] unxz is equivalent to xz --decompress. xzcat is equivalent to xz --decompress --stdout. lzma is equivalent to xz --format=lzma. unlzma is equivalent to xz --format=lzma --decompress. lzcat is equivalent to xz --format=lzma --decompress --stdout. When writing scripts that need to decompress files, it is recommended to always use the name xz with appropriate arguments (xz -d or xz -dc) instead of the names unxz and xzcat. % gnutls-cli-debug - GnuTLS debug client gnutls-cli-debug [-flags] [-flag [value]] [--option-name[[=| ]value]] TLS debug client. It sets up multiple TLS connections to a server and queries its capabilities. It was created to assist in debugging GnuTLS, but it might be useful to extract a TLS server's capabilities. It connects to a TLS server, performs tests and print the server's capabilities. If called with the `-v' parameter more checks will be performed. Can be used to check for servers with special needs or bugs. -d number, --debug=number constrained to being: % tty - print the file name of the terminal connected to standard input tty [OPTION]... Print the file name of the terminal connected to standard input. -s, --silent, --quiet print nothing, only return an exit status --help display this help and exit --version output version information and exit % csplit - split a file into sections determined by context lines csplit [OPTION]... FILE PATTERN... each piece to standard output. Read standard input if FILE is - Mandatory arguments to long options are mandatory for short options too. -b, --suffix-format=FORMAT -f, --prefix=PREFIX % systemd-cgtop - Show top control groups by their resource usage systemd-cgtop shows the top control groups of the local Linux control group hierarchy, ordered by their specified control group. If systemd-cgtop is not connected to a tty, no column headers are printed and the default is to only run Resource usage is only accounted for control groups in the relevant hierarchy, i.e. CPU usage is only accounted for control groups in the "cpuacct" hierarchy, memory usage only for those in "memory" and disk I/O usage for those in "blkio". If resource monitoring for these resources is required, it is recommended % tload - graphic representation of system load average tload [options] [tty] tload prints a graph of the current system load average to the specified tty (or the tty of the tload process if none is specified). -s, --scale number The scale option allows a vertical scale to be specified for the display (in characters between graph ticks); thus, a smaller value represents a larger scale, and vice versa. -d, --delay seconds The delay sets the delay between graph updates in seconds. % firewallctl - firewalld command line client firewallctl is an alternate command line client of the firewalld daemon. It provides interface to manage runtime and permanent configuration. things can get changed in the runtime or permanent configuration. The following options are supported: General Options -h, --help % jfs_fsck - initiate replay of the JFS transaction log, and check and repair a JFS formatted device jfs_fsck [ -afnpvV ] [ -j journal_device ] [ --omit_journal_replay ] [ --replay_journal_only ] device jfs_fsck is used to replay the JFS transaction log, check a JFS formatted device for errors, and fix any errors found. jfs_fsck must be run as root. WARNING jfs_fsck should only be used to check an unmounted file system or a file system that is mounted READ ONLY. Using jfs_fsck to check a file system mounted other than READ ONLY could seriously damage the file system! % pidof -- find the process ID of a running program. pidof [-s] [-c] [-x] [-o omitpid[,omitpid..]] [-o omitpid[,omitpid..]..] program [program..] Pidof finds the process id's (pids) of the named programs. It prints those id's on the standard output. -s Single shot - this instructs the program to only return one pid. non-root users, as they will be unable to check the current root directory of processes they do not own. -x Scripts too - this causes the program to also return process id's of shells running the named scripts. % fdformat - low-level format a floppy disk fdformat [options] device fdformat does a low-level format on a floppy disk. device is usually one of the following (for floppy % tipc - a TIPC configuration and management tool The Transparent Inter-Process Communication (TIPC) protocol offers total address transparency between processes which allows applications in a clustered computer environment to communicate quickly and reli‐ ably with each other, regardless of their location within the cluster. TIPC originated at the telecommunications manufacturer Ericsson. The first open source version of TIPC % install-info - update info/dir entries install-info [OPTION]... [INFO-FILE [DIR-FILE]] Add or remove entries in INFO-FILE from the Info directory DIR-FILE. INFO-FILE and DIR-FILE are required unless the --info-file or --dir-file (or --info-dir) options are given, respectively. --add-once add only to first matching section, not all. --align=COL start description of new entries at column COL. --calign=COL % busctl - Introspect the bus The following options are understood: --address=ADDRESS Connect to the bus specified by ADDRESS instead of using suitable defaults for either the system or user bus (see --system and --user options). --show-machine When showing the list of peers, show a column containing the names of containers they belong to. See % make - GNU make utility to maintain groups of programs make [OPTION]... [TARGET]... The make utility will determine automatically which pieces of a large program need to be recompiled, and issue the commands to recompile them. The manual describes the GNU implementation of make, which was written by Richard Stallman and Roland McGrath, and is currently maintained by Paul Smith. Our examples show C programs, since they are very common, but you can use make with any programming language whose compiler can be run with a shell command. In fact, make is not limited to programs. You can use it to describe any task where some files must be updated automatically from others whenever the others change. To prepare to use make, you must write a file called the makefile that describes the relationships among files in your program, and the states the commands for updating each file. In a program, typically the executable file is updated from object files, which are in turn made by compiling source files. % mknod - make block or character special files Mandatory arguments to long options are mandatory for short options too. -m, --mode=MODE set file permission bits to MODE, not a=rw - umask -Z set the SELinux security context to default type --context[=CTX] like -Z, or if CTX is specified then set the SELinux or SMACK security context to CTX % lsmod - Show the status of modules in the Linux Kernel lsmod lsmod is a trivial program which nicely formats the contents of the /proc/modules, showing what kernel modules are currently loaded. others. % fsfreeze --freeze|--unfreeze mountpoint fsfreeze suspends or resumes access to a filesystem. fsfreeze halts any new access to the filesystem and creates a stable image on disk. fsfreeze is intended to be used with hardware RAID devices that support the creation of snapshots. fsfreeze is unnecessary for device-mapper devices. The device-mapper (and LVM) automatically freezes a page. The mountpoint argument is the pathname of the directory where the filesystem is mounted. The filesystem % klist - list cached Kerberos tickets klist [-e] [[-c] [-l] [-A] [-f] [-s] [-a [-n]]] [-C] [-k [-t] [-K]] [-V] [cache_name|keytab_name] klist lists the Kerberos principal and Kerberos tickets held in a credentials cache, or the keys held in a keytab file. -e Displays the encryption types of the session key and the ticket for each credential in the creden‐ tial cache, or each key in the keytab file. -l If a cache collection is available, displays a table summarizing the caches present in the collec‐ tion. -A If a cache collection is available, displays the contents of all of the caches in the collection. % pdfmom - Produce PDF documents using the mom macro set pdfmom [-Tps [pdfroff options]] [groff options] files ... pdfmom [-Tpdf] [groff options] files ... pdfmom is a wrapper around groff that facilitates the production of PDF documents from files formatted with the mom macros. pdfmom prints to stdout, so output must be redirected to a destination file. The size of the final PDF If called with the -Tpdf option (which is the default), pdfmom processes files using groff's native PDF driver, gropdf. If -Tps is given, processing is passed over to pdfroff, which uses groff's PostScript % uname - print system information uname [OPTION]... Print certain system information. With no OPTION, same as -s. -a, --all print all information, in the following order, except omit -p and -i if unknown: -s, --kernel-name print the kernel name -n, --nodename print the network node hostname % printenv - print all or part of environment printenv [OPTION]... [VARIABLE]... Print the values of the specified environment VARIABLE(s). If no VARIABLE is specified, print name and value pairs for them all. -0, --null end each output line with NUL, not newline --help display this help and exit --version output version information and exit % ipcmk - make various IPC resources ipcmk [options] ipcmk allows you to create shared memory segments, message queues, and semaphore arrays. Resources can be specified with these options: -M, --shmem size for GB, etc. % mkdir - make directories mkdir [OPTION]... DIRECTORY... Create the DIRECTORY(ies), if they do not already exist. Mandatory arguments to long options are mandatory for short options too. -m, --mode=MODE set file mode (as in chmod), not a=rwx - umask -p, --parents no error if existing, make parent directories as needed -v, --verbose % mkfifo - make FIFOs (named pipes) Mandatory arguments to long options are mandatory for short options too. -m, --mode=MODE set file permission bits to MODE, not a=rw - umask -Z set the SELinux security context to default type --context[=CTX] like -Z, or if CTX is specified then set the SELinux or SMACK security context to CTX % genrandom - generate a file containing random data genrandom [-n number] {size} {filename} genrandom generates a file or a set of files containing a specified quantity of pseudo-random data, which can be used as a source of entropy for other commands on systems with no random device. -n number size The size of the file, in kilobytes, to generate. filename % mount - mount a filesystem mount [-l|-h|-V] mount -a [-fFnrsvw] [-t fstype] [-O optlist] mount [-fnrsvw] [-o options] device|dir mount [-fnrsvw] [-t fstype] [-o options] device dir All files accessible in a Unix system are arranged in one big tree, the file hierarchy, rooted at /. These files can be spread out over several devices. The mount command serves to attach the filesystem The standard form of the mount command is: % gpg-agent - Secret key management for GnuPG gpg-agent [--homedir dir] [--options file] [options] gpg-agent [--homedir dir] [--options file] [options] --server gpg-agent [--homedir dir] [--options file] [options] --daemon [command_line] gpg-agent is a daemon to manage secret (private) keys independently from any protocol. It is used as a backend for gpg and gpgsm as well as for a couple of other utilities. The agent is automatically started on demand by gpg, gpgsm, gpgconf, or gpg-connect-agent. Thus there is the agent using: gpg-connect-agent /bye % xfs_admin - change parameters of an XFS filesystem xfs_admin -V Devices that are mounted cannot be modified. Administrators must unmount filesystems before xfs_admin or -e Enables unwritten extent support on a filesystem that does not already have this enabled (for legacy filesystems, it can't be disabled anymore at mkfs time). % uncompress — expand compressed data uncompress [−cfv] [file...] The uncompress utility shall restore files to their original state after they have been compressed using the compress utility. If no files are specified, the standard input shall be uncompressed to the standard output. If the invoking process has appropriate privileges, the ownership, modes, access time, and modi‐ fication time of the original file shall be preserved. % gdbus - Tool for working with D-Bus objects gdbus introspect [--system | --session | --address address] --dest bus_name --object-path /path/to/object [--xml] [--recurse] [--only-properties] gdbus monitor [--system | --session | --address address] --dest bus_name [--object-path /path/to/object] gdbus call [--system | --session | --address address] --dest bus_name --object-path /path/to/object gdbus emit [--system | --session | --address address] --object-path /path/to/object gdbus help % systemd-tmpfiles, systemd-tmpfiles-setup.service, systemd-tmpfiles-setup-dev.service, systemd-tmpfiles- clean.service, systemd-tmpfiles-clean.timer - Creates, deletes and cleans up volatile and temporary files and directories systemd-tmpfiles-setup.service systemd-tmpfiles-setup-dev.service systemd-tmpfiles-clean.service systemd-tmpfiles-clean.timer systemd-tmpfiles creates, deletes, and cleans up volatile and temporary files and directories, based on % features an extremely fast decoder, with speed in multiple GB/s per core, typically reaching RAM speed % telinit - Change SysV runlevel the runlevel requests will be transparently translated into systemd unit activation requests. The following options are understood: --help Print a short help text and exit. --no-wall Do not send wall message before reboot/halt/power-off. % bootctl - Control the firmware and boot manager settings bootctl checks, updates, installs or removes the boot loader from the current system. bootctl status checks and prints the currently installed versions of the boot loader binaries and all current EFI boot variables. % devlink - Devlink tool OBJECT := { dev | port | monitor } -V, -Version Print the version of the devlink utility and exit. -n, -no-nice-names Turn off printing out nice names, for example netdevice ifnames instead of devlink port identifi‐ cation. % mountpoint - see if a directory or file is a mountpoint mountpoint [-d|-q] directory | file mountpoint -x device mountpoint checks whether the given directory or file is mentioned in the /proc/self/mountinfo file. -d, --fs-devno Show the major/minor numbers of the device that is mounted on the given directory. -q, --quiet Be quiet - don't print anything. % migratepages - Migrate the physical location a processes pages migratepages pid from-nodes to-nodes migratepages moves the physical location of a processes pages without any changes of the virtual address space of the process. Moving the pages allows one to change the distances of a process to its memory. If multiple nodes are specified for from-nodes or to-nodes then an attempt is made to preserve the rela‐ tive location of each page in each nodeset. Valid node specifiers % ssh-keygen — authentication key generation, management and conversion [-f output_keyfile] ssh-keygen -p [-P old_passphrase] [-N new_passphrase] [-f keyfile] ssh-keygen -i [-m key_format] [-f input_keyfile] ssh-keygen -e [-m key_format] [-f input_keyfile] ssh-keygen -y [-f input_keyfile] ssh-keygen -c [-P passphrase] [-C comment] [-f keyfile] ssh-keygen -l [-v] [-E fingerprint_hash] [-f input_keyfile] ssh-keygen -B [-f input_keyfile] ssh-keygen -F hostname [-f known_hosts_file] [-l] ssh-keygen -H [-f known_hosts_file] ssh-keygen -R hostname [-f known_hosts_file] ssh-keygen -r hostname [-f input_keyfile] [-g] % accessdb - dumps the content of a man-db database in a human readable format /usr/sbin/accessdb [-d?V] [] accessdb will output the data contained within a man-db database in a human readable form. By default, it will dump the data from /var/cache/man/index., where is dependent on the database library in use. Supplying an argument to accessdb will override this default. -d, --debug Print debugging information. -?, --help % sdiff - side-by-side merge of file differences Mandatory arguments to long options are mandatory for short options too. -o, --output=FILE operate interactively, sending output to FILE -E, --ignore-tab-expansion % gzip, gunzip, zcat - compress or expand files gunzip [ -acfhklLnNrtvV ] [-S suffix] [ name ... ] zcat [ -fhLV ] [ name ... ] Gzip reduces the size of the named files using Lempel-Ziv coding (LZ77). Whenever possible, each file is replaced by one with the extension .gz, while keeping the same ownership modes, access and modification files are specified, or if a file name is "-", the standard input is compressed to the standard output. Gzip will only attempt to compress regular files. In particular, it will ignore symbolic links. If the compressed file name is too long for its file system, gzip truncates it. Gzip attempts to trun‐ name consists of small parts only, the longest parts are truncated. For example, if file names are lim‐ % dirmngr-client - Tool to access the Dirmngr services dirmngr-client [options] [certfile|pattern] The dirmngr-client is a simple tool to contact a running dirmngr and test whether a certificate has been revoked --- either by being listed in the corresponding CRL or by running the OCSP protocol. If no dirm‐ ngr is running, a new instances will be started but this is in general not a good idea due to the huge performance overhead. The usual way to run this tool is either: dirmngr-client acert or % whereis - locate the binary, source, and manual page files for a command whereis [options] [-BMS directory... -f] name... whereis locates the binary, source and manual files for the specified command names. The supplied names are first stripped of leading pathname components and any (single) trailing extension of the form .ext (for example: .c) Prefixes of s. resulting from use of source code control are also dealt with. whereis then attempts to locate the desired program in the standard Linux places, and in the places specified by $PATH and $MANPATH. The search restrictions (options -b, -m and -s) are cumulative and apply to the subsequent name patterns on the command line. Any new search restriction resets the search mask. For example, whereis -bm ls tr -m gcc % geoiplookup - look up country using IP Address or hostname geoiplookup [-d directory] [-f filename] [-v] geoiplookup uses the GeoIP library and database to find the Country that an IP address or hostname origi‐ nates from. For example NL, Netherlands % blocks-per-group ] [ -G number-of-groups ] [ -i bytes-per-inode ] [ -I inode-size ] [ -j ] [ -J journal- options ] [ -N number-of-inodes ] [ -n ] [ -m reserved-blocks-percentage ] [ -o creator-os ] [ -O [^]fea‐ ture[,...] ] [ -q ] [ -r fs-revision-level ] [ -E extended-options ] [ -v ] [ -F ] [ -L volume-label ] [ -M last-mounted-directory ] [ -S ] [ -t fs-type ] [ -T usage-type ] [ -U UUID ] [ -V ] [ -e errors-behav‐ ior ] [ -z undo_file ] device [ fs-size ] size ] by device. % ldns-version - print out the version of the ldns-library and tools on this system ldns-version ldns-version is used to print out version information of the ldns library and tools ldns-version has no options. Written by the ldns team as an example for ldns usage. REPORTING BUGS Report bugs to . % Transform syslinux config into GRUB one. -c, --cwd=DIR current directory of syslinux [default is parent directory of input file]. -i, --isolinux assume input is an isolinux configuration file. -o, --output=FILE write output to FILE [default=stdout]. % pwconv, pwunconv, grpconv, grpunconv - convert to and from shadow passwords and groups pwconv [options] pwunconv [options] grpconv [options] grpunconv [options] The pwconv command creates shadow from passwd and an optionally existing shadow. The pwunconv command creates passwd from passwd and shadow and then removes shadow. The grpconv command creates gshadow from group and an optionally existing gshadow. % features an extremely fast decoder, with speed in multiple GB/s per core, typically reaching RAM speed % isosize - output the length of an iso9660 filesystem isosize [options] iso9660_image_file -x, --sectors Show the block count and block size in human-readable form. The output uses the term "sectors" for "blocks". -d, --divisor number % toe - table of (terminfo) entries toe [-v[n]] [-ahsuUV] file... With no options, toe lists all available terminal types by primary name with descriptions. File argu‐ ments specify the directories to be scanned; if no such arguments are given, your default terminfo direc‐ tory is scanned. If you also specify the -h option, a directory header will be issued as each directory is entered. There are other options intended for use by terminfo file maintainers: -a report on all of the terminal databases which ncurses would search, rather than only the first one that it finds. % gcc - GNU project C and C++ compiler gcc [-c|-S|-E] [-std=standard] [-g] [-pg] [-Olevel] [-Wwarn...] [-Wpedantic] [-Idir...] [-Ldir...] [-Dmacro[=defn]...] [-Umacro] [-foption...] [-mmachine-option...] [-o outfile] [@file] infile... Only the most useful options are listed here; see below for the remainder. g++ accepts mostly the same options as gcc. When you invoke GCC, it normally does preprocessing, compilation, assembly and linking. The "overall options" allow you to stop this process at an intermediate stage. For example, the -c option says not to % debugfs [ -DVwcin ] [ -b blocksize ] [ -s superblock ] [ -f cmd_file ] [ -R request ] [ -d data_source_device ] [ -z undo_file ] [ device ] The debugfs program is an interactive file system debugger. It can be used to examine and change the device is a block device (e.g., /dev/sdXX) or a file containing the file system. -w Specifies that the file system should be opened in read-write mode. Without this option, the file system is opened in read-only mode. % badblocks - search a device for bad blocks badblocks [ -svwnfBX ] [ -b block_size ] [ -c blocks_at_once ] [ -d read_delay_factor ] [ -e max_bad_blocks ] [ -i input_file ] [ -o output_file ] [ -p num_passes ] [ -t test_pattern ] device [ last_block ] [ first_block ] badblocks is used to search for bad blocks on a device (usually a disk partition). device is the special not specified, the last block on the device is used as a default. first_block is an optional parameter specifying the starting block number for the test, which allows the testing to start in the middle of the disk. If it is not specified the first block on the disk is used as a default. important that the block size is properly specified, since the block numbers which are generated are very dependent on the block size in use by the filesystem. For this reason, it is strongly recommended that % userdel - delete a user account and related files userdel [options] LOGIN The userdel command modifies the system account files, deleting all entries that refer to the user name LOGIN. The named user must exist. The options which apply to the userdel command are: -f, --force forces userdel to remove the user's home directory and mail spool, even if another user uses the same home directory or if the mail spool is not owned by the specified user. If USERGROUPS_ENAB is defined to yes in /etc/login.defs and if a group exists with the same name as the deleted user, then this % symcryptrun - Call a simple symmetric encryption tool symcryptrun --class class --program program --keyfile keyfile [--decrypt|--encrypt] [inputfile] Sometimes simple encryption tools are already in use for a long time and there might be a desire to inte‐ grate them into the GnuPG framework. The protocols and encryption methods might be non-standard or not even properly documented, so that a full-fledged encryption tool with an interface like gpg is not doable. symcryptrun provides a solution: It operates by calling the external encryption/decryption mod‐ ule and provides a passphrase for a key using the standard pinentry based mechanism through gpg-agent. build time. For encryption, the plain text must be provided on STDIN or as the argument inputfile, and the ciphertext will be output to STDOUT. For decryption vice versa. % ownership - Compaq ownership tag retriever ownership retrieves and prints the "ownership tag" that can be set on Compaq computers. Contrary to all other programs of the dmidecode package, ownership doesn't print any version information, nor labels, but -d, --dev-mem FILE Read memory from device FILE (default: /dev/mem) -h, --help Display usage information and exit % sln - create symbolic links sln source dest sln filelist that if for some reason the dynamic linker is not working, sln can be used to make symbolic links to dynamic libraries. The command line has two forms. In the first form, it creates dest as a new symbolic link to source. In the second form, filelist is a list of space-separated pathname pairs, and the effect is as if sln was executed once for each line of the file, with the two pathnames as the arguments. The sln program supports no command-line options. % gdbus-codegen - D-Bus code and documentation generator gdbus-codegen [-h, --help] [--interface-prefix org.project.Prefix] [--generate-c-code OUTFILES] [--c-namespace YourProject] [--c-generate-object-manager] [--c-generate-autocleanup none|objects|all] [--generate-docbook OUTFILES] [--xml-files FILE] [--annotate ELEMENT KEY VALUE]... FILE [FILE...] gdbus-codegen is used to generate code and/or documentation for one or more D-Bus interfaces. The tool C code (via --generate-c-code) and Docbook XML (via --generate-docbook). GENERATING C CODE When generating C code, a #GInterface -derived type is generated for each D-Bus interface. Additionally, for every generated type, FooBar, two concrete instantiable types, FooBarProxy and FooBarSkeleton, implementing said interface are also generated. The former is derived from #GDBusProxy and intended for % talkd - Talk server talkd [OPTION...] Talk daemon, using service `ntalk'. -a, --acl=FILE read site-wide ACLs from FILE -d, --debug enable debugging -i, --idle-timeout=SECONDS set idle timeout value to SECONDS -l, --logging % dbus-run-session - start a process as a new D-Bus session dbus-run-session --help dbus-run-session --version dbus-run-session is used to start a session bus instance of dbus-daemon from a shell script, and start a specified program in that session. The dbus-daemon will run for as long as the program does, after which it will terminate. One use is to run a shell with its own dbus-daemon in a text‐mode or SSH session, and have the dbus-daemon terminate automatically on leaving the sub‐shell, like this: % ldns-read-zone - read a zonefile and print it ldns-read-zone ZONEFILE pretty-printing makeup. -c Canonicalize all resource records in the zone before printing -b Include Bubble Babble encoding of DS's. % tracepath, tracepath6 - traces path to a network host discovering MTU along this path tracepath [-n] [-b] [-l pktlen] [-m max_hops] [-p port] {destination} It traces path to destination discovering MTU along this path. It uses UDP port port or some random port. It is similar to traceroute, only does not require superuser privileges and has no fancy options. tracepath6 is good replacement for traceroute6 and classic example of application of Linux error queues. error messages. Probably, it will change, when they will be updated. For now it uses Van Jacobson's trick, sweeping a range of UDP ports to maintain trace history. -n Print primarily IP addresses numerically. % msgfilter - edit translations of message catalog msgfilter [OPTION] FILTER [FILTER-OPTION] Applies a filter to all translations of a translation catalog. Mandatory arguments to long options are mandatory for short options too. Input file location: -i, --input=INPUTFILE input PO file -D, --directory=DIRECTORY add DIRECTORY to list for input files search % arpaname - translate IP addresses to the corresponding ARPA names arpaname {ipaddress ...} BIND 9 Administrator Reference Manual. Internet Systems Consortium, Inc. % ntp-keygen - Create a NTP host key ntp-keygen [-flags] [-flag [value]] [--option-name[[=| ]value]] All arguments must be options. software library has been installed, it generates keys, certificate and identity files used in public key cryptography. These files are used for cookie encryption, digital signature and challenge/response iden‐ tification algorithms compatible with the Internet standard security infrastructure. All files are in PEM-encoded printable ASCII format, so they can be embedded as MIME attachments in mail to other sites and certificate authorities. By default, files are not encrypted. % dnsdomainname - show DNS domain name dnsdomainname [OPTION...] Show domain part of the system's fully qualified host name. The tool uses gethostname to get the host name of the system and getaddrinfo to resolve it into a canoni‐ cal name. The part after the first period ('.') of the canonical name is shown. -?, --help give this help list --usage give a short usage message % ntpd - NTP daemon program The ntpd utility is an operating system daemon which sets and maintains the system time of day in syn‐ chronism with Internet standard time servers. It is a complete implementation of the Network Time Proto‐ onds. While the ultimate precision is not achievable with ordinary workstations and networks of today, % indxbib - make inverted index for bibliographic databases indxbib [ -vw ] [ -cfile ] [ -ddir ] [ -ffile ] [ -hn ] [ -istring ] [ -kn ] [ -ln ] [ -nn ] [ -ofile ] [ -tn ] [ filename... ] which is then renamed to this. If no filenames are given on the command line because the -f option has been used, and no -o option is given, the index will be named Ind.i. Bibliographic databases are divided into records by blank lines. Within a record, each fields starts with a % character at the beginning of a line. Fields have a one letter name which follows the % charac‐ ter. The values set by the -c, -n, -l and -t options are stored in the index; when the index is searched, keys % gencat — generate a formatted message catalog gencat catfile msgfile... The gencat utility shall merge the message text source file msgfile into a formatted message catalog cat‐ file. The file catfile shall be created if it does not already exist. If catfile does exist, its mes‐ sages shall be included in the new catfile. If set and message numbers collide, the new message text defined in msgfile shall replace the old message text currently contained in catfile. % grub-mkrescue - make a GRUB rescue image grub-mkrescue [OPTION...] [OPTION] SOURCE... Make GRUB CD-ROM, disk, pendrive and floppy bootable image. --compress=no|xz|gz|lzo compress GRUB files [optional] -d, --directory=DIR use images and modules under DIR [default=/usr/lib/grub/] --fonts=FONTS install FONTS [default=unicode] % xfs_fsr - filesystem reorganizer for XFS xfs_fsr [-vdg] [-t seconds] [-p passes] [-f leftoff] [-m mtab] xfs_fsr [-vdg] [xfsdev | file] ... xfs_fsr -V xfs_fsr is applicable only to XFS filesystems. xfs_fsr improves the organization of mounted filesystems. The reorganization algorithm operates on one file at a time, compacting or otherwise improving the layout of the file extents (contiguous blocks of file data). The following options are accepted by xfs_fsr. The -m, -t, and -f options have no meaning if any filesystems or files are specified on the command line. % touch - change file timestamps touch [OPTION]... FILE... Update the access and modification times of each FILE to the current time. A FILE argument that does not exist is created empty, unless -c or -h is supplied. A FILE argument string of - is handled specially and causes touch to change the times of the file associ‐ ated with standard output. Mandatory arguments to long options are mandatory for short options too. -a change only the access time % chacl - change the access control list of a file or directory chacl acl pathname... chacl -b acl dacl pathname... chacl -d dacl pathname... chacl -R pathname... chacl -D pathname... chacl -B pathname... chacl -l pathname... chacl -r pathname... chacl is an IRIX-compatibility command, and is maintained for those users who are familiar with its use % secret-tool - Store and retrieve passwords secret-tool store --label='Label' {attribute} {value} ... secret-tool lookup {attribute} {value} ... secret-tool clear {attribute} {value} ... secret-tool search [--all]{attribute} {value} ... secret-tool is a command line tool that can be used to store and retrieve passwords. Each password is stored in an item. Items are uniquely identified by a set of attribute keys and values. When storing a password you must specify unique pairs of attributes names and values, and when looking up a password you provide the same attribute name and value pairs. % cations to provide batch processing features. database file. If the database file does not exist, it will be created. If the database file does exist, it will be opened. For example, to create a new database file named "mydata.db", create a table named "memos" and insert a couple of records into that table: % setarch - change reported architecture in new program environment and set personality flags setarch arch [options] [program [argument...]] arch [options] [program [argument...]] setarch --list|-h|-V various personality options. The default program is /bin/sh. --list List the architectures that setarch knows about. Whether setarch can actually set each of these architectures depends on the running kernel. % glib-gettextize - gettext internationalization utility glib-gettextize [OPTION...] [DIRECTORY] glib-gettextize helps to prepare a source package for being internationalized through gettext. It is a variant of the gettextize that ships with gettext. glib-gettextize differs from gettextize in that it doesn't create an intl/ subdirectory and doesn't modify po/ChangeLog (note that newer versions of gettextize behave like this when called with the --no-changelog option). --help print help and exit % ldns-compare-zones - read and compare two zonefiles and print differences ldns-compare-zones reads two DNS zone files and prints number of differences. Output is formated to: +NUM_INS -NUM_DEL ~NUM_CHG are considered inserted, and counted as NUM_INS. If an owner name is present in both, but there is a dif‐ ference in the amount or content of the records, these are considered changed, and counted as NUM_CHG. % With no FILE, or when FILE is -, read standard input. -b, --binary read in binary mode -c, --check --tag create a BSD-style checksum % fsck.cramfs - fsck compressed ROM file system fsck.cramfs [options] file fsck.cramfs is used to check the cramfs file system. -v, --verbose Enable verbose messaging. -b, --blocksize blocksize Use this blocksize, defaults to page size. Must be equal to what was set at creation time. Only used for --extract. --extract[=directory] % xmlcatalog - Command line tool to parse and manipulate XML or SGML catalog files. --noout | --no-super-update | [-v | --verbose]] {CATALOGFILE} {ENTITIES...} xmlcatalog is a command line application allowing users to monitor and manipulate XML and SGML catalogs. Its functions can be invoked from a single command from the command line, or it can perform multiple functions in interactive mode. It can operate on both XML and SGML files. xmlcatalog accepts the following options (in alphabetical order): --add TYPE ORIG REPLACE % xz, unxz, xzcat, lzma, unlzma, lzcat - Compress or decompress .xz and .lzma files xz [option...] [file...] unxz is equivalent to xz --decompress. xzcat is equivalent to xz --decompress --stdout. lzma is equivalent to xz --format=lzma. unlzma is equivalent to xz --format=lzma --decompress. lzcat is equivalent to xz --format=lzma --decompress --stdout. When writing scripts that need to decompress files, it is recommended to always use the name xz with appropriate arguments (xz -d or xz -dc) instead of the names unxz and xzcat. % irqbalance - distribute hardware interrupts across processors on a multiprocessor system irqbalance The purpose of irqbalance is to distribute hardware interrupts across processors on a multiprocessor sys‐ tem in order to increase performance. -o, --oneshot Causes irqbalance to be run once, after which the daemon exits. -d, --debug Causes irqbalance to print extra debug information. Implies --foreground. -f, --foreground % xfs_ncheck - generate pathnames from i-numbers for XFS xfs_ncheck [ -i ino ] ... [ -f ] [ -s ] [ -l logdev ] device xfs_ncheck -V xfs_ncheck with no -i arguments generates an inode number and pathname list of all files on the given order. The filesystem to be examined is specified by the device argument, which should be the disk or volume device for the filesystem. Filesystems stored in files can also be checked, using the -f flag. -f Specifies that the filesystem image to be processed is stored in a regular file at device (see into an ordinary file. % bzcat - decompresses files to stdout bzcat [ -s ] [ filenames ... ] coding. Compression is generally considerably better than that achieved by more conventional The command-line options are deliberately very similar to those of GNU gzip, but they are not identical. % btrfs-rescue - Recover a damaged btrfs filesystem btrfs rescue btrfs rescue is used to try to recover a damaged btrfs filesystem. chunk-recover [options] Recover the chunk tree by scanning the devices Options -y assume an answer of yes to all questions. % tracepath, tracepath6 - traces path to a network host discovering MTU along this path tracepath [-n] [-b] [-l pktlen] [-m max_hops] [-p port] {destination} It traces path to destination discovering MTU along this path. It uses UDP port port or some random port. It is similar to traceroute, only does not require superuser privileges and has no fancy options. tracepath6 is good replacement for traceroute6 and classic example of application of Linux error queues. error messages. Probably, it will change, when they will be updated. For now it uses Van Jacobson's trick, sweeping a range of UDP ports to maintain trace history. -n Print primarily IP addresses numerically. % coredumpctl - Retrieve and process saved core dumps and metadata coredumpctl is a tool that can be used to retrieve and process core dumps and metadata which were saved The following options are understood: -h, --help Print a short help text and exit. --version Print a short version string and exit. % -D user_dn tion on the LDAP server. -w passwd -H ldapuri % xfs_growfs, xfs_info - expand an XFS filesystem xfs_growfs [ -dilnrx ] [ -D size ] [ -e rtextsize ] [ -L size ] [ -m maxpct ] [ -t mtab ] [ -R size ] mount-point xfs_growfs -V xfs_info [ -t mtab ] mount-point xfs_info -V The existing contents of the filesystem are undisturbed, and the added space becomes available for addi‐ tional file storage. % tr - translate or delete characters Translate, squeeze, and/or delete characters from standard input, writing to standard output. -c, -C, --complement -d, --delete -s, --squeeze-repeats replace each sequence of a repeated character that is listed in the last specified SET, with a single occurrence of that character % rarp - manipulate the system RARP table rarp [-V] [--version] [-h] [--help] rarp -a rarp [-v] -d hostname ... rarp [-v] [-t type] -s hostname hw_addr replacement RARP daemon, see ftp://ftp.dementia.org/pub/net-tools Rarp manipulates the kernel's RARP table in various ways. The primary options are clearing an address mapping entry and manually setting up one. For debugging purposes, the rarp program also allows a com‐ plete dump of the RARP table. % kadmin [-O|-N] [-r realm] [-p principal] [-q query] [[-c cache_name]|[-k [-t keytab]]|-n] [-w password] [-s admin_server[:port]] kadmin.local [-r realm] [-p principal] [-q query] [-d dbname] [-e enc:salt ...] [-m] [-x db_args] vide nearly identical functionalities; the difference is that kadmin.local directly accesses the KDC man page will use "kadmin" to refer to both versions. kadmin provides for the maintenance of Kerberos principals, password policies, and service key tables (keytabs). The remote kadmin client uses Kerberos to authenticate to kadmind using the service principal kad‐ min/ADMINHOST (where ADMINHOST is the fully-qualified hostname of the admin server) or kadmin/admin. If % machinectl - Control the systemd machine manager considered running instances of: · Virtual Machines (VMs) that virtualize hardware to run full operating system (OS) instances (including their kernels) in a virtualized environment on top of the host OS. · Containers that share the hardware and OS kernel with the host OS, in order to run OS userspace instances on top the host OS. % With no FILE, or when FILE is -, read standard input. -b, --binary read in binary mode -c, --check --tag create a BSD-style checksum % less - opposite of more less -? less --help less -V less --version less [-[+]aABcCdeEfFgGiIJKLmMnNqQrRsSuUVwWX~] [-b space] [-h lines] [-j line] [-k keyfile] [-{oO} logfile] [-p pattern] [-P prompt] [-t tag] [-T tagsfile] [-x tab,...] [-y lines] [-[z] lines] [-# shift] [+[+]cmd] [--] [filename]... movement. Also, less does not have to read the entire input file before starting, so with large input % nproc - print the number of processing units available nproc [OPTION]... of online processors --all print the number of installed processors --ignore=N if possible, exclude N processing units --help display this help and exit --version % unicode_start - put keyboard and console in unicode mode unicode_start [font [umap]] put accordingly. The parameter font is a font that is loaded. It should have a built-in Unicode map, or, if it hasn't, such a map can be given explicitly as second parameter. When no font was specified, the current font is % With no FILE, or when FILE is -, read standard input. -b, --binary read in binary mode -c, --check --tag create a BSD-style checksum % ldns-rrsig - print out the inception and expiration dates in human readable form ldns-rrsig domain [ type ] ldns-rrsig is used to print the expiration and inception date of a RRSIG. The first argument is a domain name. ldns-rrsig will query the authoritative servers for that domain to get a list of RRSIGs. It will then print out the inception and experiration dates for the RRSIG covering the SOA record. If the second argument type is given the RRSIG covering that type will be shown. Written by the ldns team as an example for ldns usage. REPORTING BUGS Report bugs to . % blkdiscard - discard sectors on a device blkdiscard [options] [-o offset] [-l length] device ior based on range or size, as explained below. The device argument is the pathname of the block device. WARNING: All data in the discarded region on the device will be lost! % lvdisplay — display attributes of a logical volume lockingfailure] [--ignoreskippedcluster] [--maps] [--nosuffix] [-P|--partial] [--reportformat {basic|json}] [-S|--select Selection] [--units hHbBsSkKmMgGtTpPeE] [-v|--verbose] [--version] [Vol‐ tion] ...] [-d|--debug] [-h|-?|--help] [--ignorelockingfailure] [--ignoreskippedcluster] [--logonly] [--noheadings] [--nosuffix] [-P|--partial] [--reportformat {basic|json}] [--segments] [--separator Sepa‐ lvdisplay allows you to see the attributes of a logical volume like size, read/write status, snapshot % xmllint - command line XML tool xmllint [--version | --debug | --shell | --xpath "XPath_expression" | --debugent | --copy | --recover | --noent | --noout | --nonet | --path "PATH(S)" | --load-trace | --htmlout | --nowrap | --valid | --postvalid | --dtdvalid URL | --dtdvalidfpi FPI | --timing | --output FILE | --repeat | --insert | --compress | --html | --xmlout | --push | --memory | --maxmem NBBYTES | --nowarning | --noblanks | --nocdata | --format | --encode ENCODING | --dropdtd | --nsclean | --testIO | --catalogs | --nocatalogs | --auto | --xinclude | --noxincludenode | --loaddtd | --dtdattr | --stream | --walker | --pattern PATTERNVALUE | --chkregister | --relaxng SCHEMA | --schema SCHEMA xmllint --help The xmllint program parses one or more XML files, specified on the command line as XML-FILE (or the standard input if the filename provided is - ). It prints various types of output, depending upon the % gcc - GNU project C and C++ compiler gcc [-c|-S|-E] [-std=standard] [-g] [-pg] [-Olevel] [-Wwarn...] [-Wpedantic] [-Idir...] [-Ldir...] [-Dmacro[=defn]...] [-Umacro] [-foption...] [-mmachine-option...] [-o outfile] [@file] infile... Only the most useful options are listed here; see below for the remainder. g++ accepts mostly the same options as gcc. When you invoke GCC, it normally does preprocessing, compilation, assembly and linking. The "overall options" allow you to stop this process at an intermediate stage. For example, the -c option says not to % gcov - coverage testing tool gcov [-v|--version] [-h|--help] [-a|--all-blocks] [-b|--branch-probabilities] [-c|--branch-counts] [-d|--display-progress] [-f|--function-summaries] [-i|--intermediate-format] [-l|--long-file-names] [-m|--demangled-names] [-n|--no-output] [-o|--object-directory directory|file] [-p|--preserve-paths] [-r|--relative-only] [-s|--source-prefix directory] % libtoolize [OPTION]... Prepare a package to use libtool. -c, --copy copy files rather than symlinking them --debug enable verbose shell tracing -n, --dry-run print commands rather than running them % cpp - The C Preprocessor cpp [-Dmacro[=defn]...] [-Umacro] [-Idir...] [-iquotedir...] [-Wwarn...] [-M|-MM] [-MG] [-MF filename] [-MP] [-MQ target...] [-MT target...] [-P] [-fno-working-directory] [-x language] [-std=standard] infile outfile Only the most useful options are listed here; see below for the remainder. The C preprocessor, often known as cpp, is a macro processor that is used automatically by the C compiler % wall - write a message to all users wall [-n] [-t timeout] [message | file] wall displays a message, or the contents of a file, or otherwise its standard input, on the terminals of all currently logged in users. The command will wrap lines that are longer than 79 characters. Short lines are whitespace padded to have 79 characters. The command will always put a carriage return and new line at the end of each line. Only the superuser can write on the terminals of users who have chosen to deny messages or are using a program which automatically denies messages. Reading from a file is refused when the invoker is not superuser and the program is suid or sgid. % sftp — secure file transfer program [-i identity_file] [-l limit] [-o ssh_option] [-P port] [-R num_requests] [-S program] [-s subsystem | sftp_server] host sftp [user@]host[:file ...] sftp [user@]host[:dir[/]] sftp -b batchfile [user@]host compression. sftp connects and logs into the specified host, then enters an interactive command mode. The second usage format will retrieve files automatically if a non-interactive authentication method is used; otherwise it will do so after successful interactive authentication. % systemd-cat - Connect a pipeline or program's output with the journal filter tool in a shell pipeline to pass the output the previous pipeline element generates to the journal. If no parameter is passed, systemd-cat will write everything it reads from standard input (stdin) to the journal. If parameters are passed, they are executed as command line with standard output (stdout) and standard error output (stderr) connected to the journal, so that all it writes is stored in the journal. % glilypond — integrate lilypond parts into groff glilypond [ options] [-] [--] [ filespec ....] glilypond transforms sheet music written in the lilypond language into the groff(7) language using the Files in groff language and standard input can be provided as arguments. Breaking Options -?|-h|--help|--usage Print help or usage information, then leave the program. --version % hostname - show or set system host name Show or set the system's host name. -a, --aliases alias names -d, --domain DNS domain name -f, --fqdn, --long DNS host name or FQDN % systemd-sysusers, systemd-sysusers.service - Allocate system users and groups systemd-sysusers.service systemd-sysusers creates system users and groups, based on the file format and location specified in If invoked with no arguments, it applies all directives from all files found. If one or more filenames are passed on the command line, only the directives in these files are applied. If only the basename of a string - is specified as filename, entries from the standard input of the process are read. % dnssec-keygen - DNSSEC key generation tool [-D date/offset] [-D sync date/offset] [-E engine] [-f flag] [-G] [-g generator] [-h] [-I date/offset] [-i interval] [-K directory] [-k] [-L ttl] [-P date/offset] [-P sync date/offset] [-p protocol] [-q] [-R date/offset] [-r randomdev] [-S key] [-s strength] [-t type] [-V] [-v level] [-z] {name} The name of the key is specified on the command line. For DNSSEC keys, this must match the name of the zone for which the key is being generated. % msgen - create English message catalog msgen [OPTION] INPUTFILE Creates an English translation catalog. The input file is the last created English PO file, or a PO Tem‐ plate file (generally created by xgettext). Untranslated entries are assigned a translation that is identical to the msgid. Mandatory arguments to long options are mandatory for short options too. Input file location: INPUTFILE input PO or POT file -D, --directory=DIRECTORY % srptool - GnuTLS SRP tool srptool [-flags] [-flag [value]] [--option-name[[=| ]value]] All arguments must be options. Simple program that emulates the programs in the Stanford SRP (Secure Remote Password) libraries using GnuTLS. It is intended for use in places where you don't expect SRP authentication to be the used for system users. In brief, to use SRP you need to create two files. These are the password file that holds the users and the verifiers associated with them and the configuration file to hold the group parameters (called tpasswd.conf). % install - copy files and set attributes install [OPTION]... [-T] SOURCE DEST install [OPTION]... SOURCE... DIRECTORY install [OPTION]... -t DIRECTORY SOURCE... install [OPTION]... -d DIRECTORY... want to download and install a ready-to-use package on a GNU/Linux system, you should instead be using a In the first three forms, copy SOURCE to DEST or multiple SOURCE(s) to the existing DIRECTORY, while set‐ TORY(ies). % modinfo - Show information about a Linux Kernel module modinfo [-0] [-F field] [-k kernel] [modulename|filename...] modinfo -V modinfo -h modinfo extracts information from the Linux Kernel modules given on the command line. If the module name when loading kernel modules. modinfo by default lists each attribute of the module in form fieldname : value, for easy reading. The filename is listed the same way (although it's not really an attribute). % scriptreplay - play back typescripts, using timing information scriptreplay [options] [-t] timingfile [typescript [divisor]] rhythm as it originally appeared when the script was recorded. The replay simply displays the information again; the programs that were run when the typescript was being recorded are not run again. Since the same information is simply being displayed, scriptreplay is only guaranteed to work properly if run on the same type of terminal the typescript was recorded on. which scriptreplay is sending its output. % routel - list routes with pretty output format routef - flush routes routel [tablenr [raw ip args...]] routef The routel script will list routes in a format that some might consider easier to interpret then the ip route list equivalent. The routef script does not take any arguments and will simply flush the routing table down the drain. FILES /usr/bin/routef /usr/bin/routel % xzcmp, xzdiff, lzcmp, lzdiff - compare compressed files from which the compression format suffix has been stripped. If two files are specified, then they are served. The names lzcmp and lzdiff are provided for backward compatibility with LZMA Utils. % ldnsd - simple daemon example code ldnsd port zone zonefile server! ldnsd takes a port, zone and zonefile as arguments. Written by the ldns team as an example for ldns usage. REPORTING BUGS Report bugs to . % ncursesw6-config - helper script for ncurses libraries ncursesw6-config [options] libraries. --prefix echos the package-prefix of ncurses --exec-prefix echos the executable-prefix of ncurses --cflags % bsdcat — expand files to standard output bsdcat [options] [files] bsdcat expands files to standard output. decompressed data it written to standard output. To decompress a file: bsdcat example.txt.gz > example.txt % mesg - display (or do not display) messages from other users mesg [option] [n|y] The mesg utility is invoked by a user to control write access others have to the terminal device associ‐ Traditionally, write access is allowed by default. However, as users become more conscious of various security risks, there is a trend to remove write access by default, at least for the primary login shell. To make sure your ttys are set the way you want them to be set, mesg should be executed in your login scripts. n Disallow messages. % pvmove — move physical extents [-d|--debug] [-h|--help] [-i|--interval Seconds] [--noudevsync] [--reportformat {basic|json}] [-v|--ver‐ bose] [-n|--name LogicalVolume] [SourcePhysicalVolume[:PE[-PE]...] [DestinationPhysicalVol‐ ume[:PE[-PE]...]...]] pvmove allows you to move the allocated physical extents (PEs) on SourcePhysicalVolume to one or more extents used by that LV will be moved to free (or specified) extents on DestinationPhysicalVolume(s). If no DestinationPhysicalVolume is specified, the normal allocation rules for the Volume Group are used. If pvmove gets interrupted for any reason (e.g. the machine crashes) then run pvmove again without any PhysicalVolume arguments to restart any moves that were in progress from the last checkpoint. Alterna‐ tively use pvmove --abort at any time to abort. The resulting location of logical volumes after an abort % makeinfo [OPTION]... TEXINFO-FILE... Translate Texinfo source documentation to various other formats, by default Info files suitable for read‐ ing online with Emacs or standalone GNU Info. not depend on the installed name. General options: --document-language=STR locale to use in translating Texinfo keywords for the output document (default C). --error-limit=NUM % lsof - list open files lsof [ -?abChKlnNOPRtUvVX ] [ -A A ] [ -c c ] [ +c c ] [ +|-d d ] [ +|-D D ] [ +|-e s ] [ +|-E ] [ +|-f [cfgGn] ] [ -F [f] ] [ -g [s] ] [ -i [i] ] [ -k k ] [ +|-L [l] ] [ +|-m m ] [ +|-M ] [ -o [o] ] [ -p s ] [ +|-r [t[m]] ] [ -s [p:s] ] [ -S [t] ] [ -T [t] ] [ -u s ] [ +|-w ] [ -x [fl] ] [ -z [z] ] [ -Z [Z] ] [ -- ] [names] % setcap - set file capabilities setcap [-q] [-v] (capabilities|-|-r) filename [ ... capabilitiesN fileN ] In the absence of the -v (verify) option setcap sets the capabilities of each specified filename to the capabilities specified. The -v option is used to verify that the specified capabilities are currently associated with the file. The special capability string, '-', can be used to indicate that capabilities are read from the standard The special capability string, '-r', is used to remove a capability set from a file. % jfs_tune - adjust tunable file system parameters on JFS jfs_tune [options] device jfs_tune adjusts tunable parameters on a Linux JFS file system or external journal. jfs_tune must be run as root. system or JFS external journal has been created. -J device=external-journal Attach the JFS external journal located on external-journal to the JFS file system on device. The external journal must already have been created using the command. More than one file system % resizecons - change kernel idea of the console size resizecons COLSxROWS resizecons -lines ROWS The resizecons command tries to change the videomode of the console. There are several aspects to this: (a) the kernel must know about it, (b) the hardware must know about it, (c) user programs must know about console screen memory for all virtual consoles, and might fail if there is not enough memory. (In that The most difficult part of this is (b), since it requires detailed knowledge of the video card hardware, % firewalld - Dynamic Firewall Manager firewalld provides a dynamically managed firewall with support for network/firewall zones to define the ethernet bridges and has a separation of runtime and permanent configuration options. It also supports an interface for services or applications to add firewall rules directly. These are the command line options of firewalld: -h, --help Prints a short help text and exists. % mkinitcpio - Create an initial ramdisk environment mkinitcpio [options] Creates an initial ramdisk environment for booting the linux kernel. The initial ramdisk is in essence a very small environment (early userspace) which loads various kernel modules and sets up necessary things filesystems and root filesystems on a software RAID array. mkinitcpio allows for easy extension with custom hooks, has autodetection at runtime, and many other features. -A, --addhooks hooks Add the additional hooks to the image. These will be processed in order after all other hooks from times. % chage - change user password expiry information chage [options] LOGIN The chage command changes the number of days between password changes and the date of the last password The options which apply to the chage command are: -d, --lastday LAST_DAY be expressed in the format YYYY-MM-DD (or the format more commonly used in your area). -E, --expiredate EXPIRE_DATE % groupadd - create a new group groupadd [options] group The groupadd command creates a new group account using the values specified on the command line plus the default values from the system. The new group will be entered into the system files as needed. The options which apply to the groupadd command are: -f, --force exists. When used with -g, and the specified GID already exists, another (unique) GID is chosen (i.e. -g is turned off). % features an extremely fast decoder, with speed in multiple GB/s per core, typically reaching RAM speed % workers] [-P pid_file] [-T time_offset] The -r realm option specifies the realm for which the server should provide service. does not apply to the LDAP database. The -k keytype option specifies the key type of the master key to be entered manually as a password when -m is given; the default is des-cbc-crc. % env - run a program in a modified environment Mandatory arguments to long options are mandatory for short options too. -i, --ignore-environment start with an empty environment -0, --null end each output line with NUL, not newline % mdadm - manage MD devices aka Linux Software RAID mdadm [mode] [options] devices (typically disk drives or partitions thereof) to be combined into a single device to hold (for example) a single filesystem. Some RAID levels include redundancy and so can survive some degree of device failure. Linux Software RAID devices are implemented through the md (Multiple Devices) device driver. MULTIPATH is not a Software RAID mechanism, but does involve multiple devices: each device is a path to % features an extremely fast decoder, with speed in multiple GB/s per core, typically reaching RAM speed % bc - An arbitrary precision calculator language bc [ -hlwsqv ] [long-options] [ file ... ] bc is a language that supports arbitrary precision numbers with interactive execution of statements. There are some similarities in the syntax to the C programming language. A standard math library is available by command line option. If requested, the math library is defined before processing any files. bc starts by processing code from all the files listed on the command line in the order listed. After all files have been processed, bc reads from the standard input. All code is executed as it is read. (If a file contains a command to halt the processor, bc will never read from the standard input.) document describes the language accepted by this processor. Extensions will be identified as such. % With no FILE, or when FILE is -, read standard input. -b, --binary read in binary mode -c, --check --tag create a BSD-style checksum % taskset - set or retrieve a process's CPU affinity taskset [options] mask command [argument...] taskset [options] -p [mask] pid taskset is used to set or retrieve the CPU affinity of a running process given its pid, or to launch a new command with a given CPU affinity. CPU affinity is a scheduler property that "bonds" a process to a given set of CPUs on the system. The Linux scheduler will honor the given CPU affinity and the process scheduler attempts to keep processes on the same CPU as long as practical for performance reasons. Therefore, forcing a specific CPU affinity is useful only in certain applications. The CPU affinity is represented as a bitmask, with the lowest order bit corresponding to the first logi‐ % nm - list symbols from object files nm [-A|-o|--print-file-name] [-a|--debug-syms] [-B|--format=bsd] [-C|--demangle[=style]] [-D|--dynamic] [-fformat|--format=format] [-g|--extern-only] [-h|--help] [-l|--line-numbers] [-n|-v|--numeric-sort] [-P|--portability] [-p|--no-sort] [-r|--reverse-sort] [-S|--print-size] [-s|--print-armap] [-t radix|--radix=radix] [-u|--undefined-only] [-V|--version] [--plugin name] [--size-sort] [--special-syms] [--synthetic] [--target=bfdname] [objfile...] % gropdf - PDF driver for groff gropdf [-delvs] [-F dir] [-p papersize] [-y foundry] [-u [cmapfile]] [files ...] It is possible to have whitespace between a command line option and its parameter. gropdf translates the output of GNU troff to PDF. Normally gropdf should be invoked by using the groff command with a -Tpdf option. If no files are given, gropdf reads the standard input. A filename of - also causes gropdf to read the standard input. PDF output is written to the standard output. When gropdf is run by groff options can be passed to gropdf using groff's -P option. See section FONT INSTALLATION below for a guide how to install fonts for gropdf. -d Include debug information as comments within the PDF. Also produces an uncompressed PDF. % ksu - Kerberized super-user ksu [ target_user ] [ -n target_principal_name ] [ -c source_cache_name ] [ -k ] [ -r time ] [ -pf ] [ -l lifetime ] [ -z | Z ] [ -q ] [ -e command [ args ... ] ] [ -a [ args ... ] ] REQUIREMENTS use ksu. ksu is a Kerberized version of the su program that has two missions: one is to securely change the real and effective user ID to that of the target user, and the other is to create a new security context. For the sake of clarity, all references to and attributes of the user invoking the program will start with "source" (e.g., "source user", "source cache", etc.). % msgcomm - match two message catalogs msgcomm [OPTION] [INPUTFILE]... Find messages which are common to two or more of the specified PO files. By using the --more-than print the unique messages). Translations, comments and extracted comments will be preserved, but only from the first PO file to define them. File positions from all PO files will be cumulated. Mandatory arguments to long options are mandatory for short options too. Input file location: INPUTFILE ... input files % reiserfsck - The checking tool for the ReiserFS filesystem. reiserfsck [ -aprVy ] [ --rebuild-sb | --check | --fix-fixable | --rebuild-tree | --clean-attributes ] [ -j | --journal device ] [ -z | --adjust-size ] [ -n | --nolog ] [ -B | --badblocks file ] [ -l | --log‐ file file ] [ -q | --quiet ] [ -y | --yes ] [ -f | --force ] [ -S | --scan-whole-partition ] [ --no-jour‐ nal-available ] device Reiserfsck searches for a Reiserfs filesystem on a device, replays any necessary transactions, and either checks or repairs the file system. device is the special file corresponding to a device or to a partition (e.g /dev/hdXX for an IDE disk partition or /dev/sdXX for a SCSI disk partition). --rebuild-sb % xfs_metadump - copy XFS filesystem metadata to a file xfs_metadump [ -aefFgow ] [ -m max_extents ] ] [ -l logdev ] source target xfs_metadump -V xfs_metadump is a debugging tool that copies the metadata from an XFS filesystem to a file. The source argument must be the pathname of the device or file containing the XFS filesystem and the target argument output to be redirected to another program such as a compression application. xfs_metadump does not alter the source filesystem in any way. The target image is a contiguous (non- sparse) file containing all the filesystem's metadata and indexes to where the blocks were copied from. % ldd - print shared object dependencies ldd [option]... file... ldd prints the shared objects (shared libraries) required by each program or shared object specified on the command line. An example of its use and output is the following: $ ldd /bin/ls % expand - convert tabs to spaces expand [OPTION]... [FILE]... Convert tabs in each FILE to spaces, writing to standard output. With no FILE, or when FILE is -, read standard input. Mandatory arguments to long options are mandatory for short options too. -i, --initial do not convert tabs after non blanks -t, --tabs=NUMBER % basename - strip directory and suffix from filenames Mandatory arguments to long options are mandatory for short options too. -a, --multiple -s, --suffix=SUFFIX remove a trailing SUFFIX; implies -a % safety mechanism. The -f option disables this safety mechanism. -h Display a usage message. -n Dry-run; do not actually write blocks back to the filesystem. % mkfs.btrfs - create a btrfs filesystem mkfs.btrfs [-A|--alloc-start ] [-b|--byte-count ] [-d|--data ] [-m|--metadata ] [-M|--mixed] [-l|--leafsize ] [-n|--nodesize ] [-s|--sectorsize ] [-L|--label