busybox(1)

version 1.30.1

2019-11-04

Aliases: dumpleases(1), logread(1), klogd(8), syslogd(8), udhcpc(8), udhcpd(8)

busybox-static

Static linked version of Busybox, a compact UNIX utility collection

busybox

Statically linked binary providing simplified versions of system commands

NAME

BusyBox - The Swiss Army Knife of Embedded Linux

SYNTAX


 busybox <applet> [arguments...]  # or

 <applet> [arguments...]          # if symlinked

DESCRIPTION

BusyBox combines tiny versions of many common UNIX utilities into a single small executable. It provides minimalist replacements for most of the utilities you usually find in GNU coreutils, util-linux, etc. The utilities in BusyBox generally have fewer options than their full-featured GNU cousins; however, the options that are included provide the expected functionality and behave very much like their GNU counterparts.

BusyBox has been written with size-optimization and limited resources in mind. It is also extremely modular so you can easily include or exclude commands (or features) at compile time. This makes it easy to customize your embedded systems. To create a working system, just add /dev, /etc, and a Linux kernel. BusyBox provides a fairly complete POSIX environment for any small or embedded system.

BusyBox is extremely configurable. This allows you to include only the components you need, thereby reducing binary size. Run ’make config’ or ’make menuconfig’ to select the functionality that you wish to enable. Then run ’make’ to compile BusyBox using your configuration.

After the compile has finished, you should use ’make install’ to install BusyBox. This will install the ’bin/busybox’ binary, in the target directory specified by CONFIG_PREFIX. CONFIG_PREFIX can be set when configuring BusyBox, or you can specify an alternative location at install time (i.e., with a command line like ’make CONFIG_PREFIX=/tmp/foo install’). If you enabled any applet installation scheme (either as symlinks or hardlinks), these will also be installed in the location pointed to by CONFIG_PREFIX.

USAGE

BusyBox is a multi-call binary. A multi-call binary is an executable program that performs the same job as more than one utility program. That means there is just a single BusyBox binary, but that single binary acts like a large number of utilities. This allows BusyBox to be smaller since all the built-in utility programs (we call them applets) can share code for many common operations.

You can also invoke BusyBox by issuing a command as an argument on the command line. For example, entering


        /bin/busybox ls

will also cause BusyBox to behave as ’ls’.

Of course, adding ’/bin/busybox’ into every command would be painful. So most people will invoke BusyBox using links to the BusyBox binary.

For example, entering


        ln -s /bin/busybox ls
        ./ls

will cause BusyBox to behave as ’ls’ (if the ’ls’ command has been compiled into BusyBox). Generally speaking, you should never need to make all these links yourself, as the BusyBox build system will do this for you when you run the ’make install’ command.

If you invoke BusyBox with no arguments, it will provide you with a list of the applets that have been compiled into your BusyBox binary.

COMMON OPTIONS

Most BusyBox applets support the --help argument to provide a terse runtime description of their behavior. If the CONFIG_FEATURE_VERBOSE_USAGE option has been enabled, more detailed usage information will also be available.

COMMANDS

Currently available applets include:


        [, [[, acpid, adjtimex, ar, arch, arp, arping, ash, awk, basename,
        bc, blkdiscard, blockdev, brctl, bunzip2, busybox, bzcat, bzip2,
        cal, cat, chgrp, chmod, chown, chpasswd, chroot, chvt, clear, cmp,
        cp, cpio, crond, crontab, cttyhack, cut, date, dc, dd, deallocvt,
        depmod, devmem, df, diff, dirname, dmesg, dnsdomainname, dos2unix,
        dpkg, dpkg-deb, du, dumpkmap, dumpleases, echo, ed, egrep, env,
        expand, expr, factor, fallocate, false, fatattr, fdisk, fgrep, find,
        fold, free, freeramdisk, fsfreeze, fstrim, ftpget, ftpput, getopt,
        getty, grep, groups, gunzip, gzip, halt, head, hexdump, hostid,
        hostname, httpd, hwclock, i2cdetect, i2cdump, i2cget, i2cset, id,
        ifconfig, ifdown, ifup, init, insmod, ionice, ip, ipcalc, ipneigh,
        kill, killall, klogd, last, less, link, linux32, linux64, linuxrc,
        ln, loadfont, loadkmap, logger, login, logname, logread, losetup,
        ls, lsmod, lsscsi, lzcat, lzma, lzop, md5sum, mdev, microcom, mkdir,
        mkdosfs, mke2fs, mkfifo, mknod, mkpasswd, mkswap, mktemp, modinfo,
        modprobe, more, mount, mt, mv, nameif, nc, netstat, nl, nologin,
        nproc, nsenter, nslookup, nuke, od, openvt, partprobe, passwd,
        paste, patch, pidof, ping, ping6, pivot_root, poweroff, printf, ps,
        pwd, rdate, readlink, realpath, reboot, renice, reset, resume, rev,
        rm, rmdir, rmmod, route, rpm, rpm2cpio, run-init, run-parts, sed,
        seq, setkeycodes, setpriv, setsid, sh, sha1sum, sha256sum,
        sha512sum, shred, shuf, sleep, sort, ssl_client, start-stop-daemon,
        stat, static-sh, strings, stty, su, sulogin, svc, svok, swapoff,
        swapon, switch_root, sync, sysctl, syslogd, tac, tail, tar, taskset,
        tc, tee, telnet, telnetd, test, tftp, time, timeout, top, touch, tr,
        traceroute, traceroute6, true, truncate, tty, tunctl, ubirename,
        udhcpc, udhcpd, uevent, umount, uname, uncompress, unexpand, uniq,
        unix2dos, unlink, unlzma, unshare, unxz, unzip, uptime, usleep,
        uudecode, uuencode, vconfig, vi, w, watch, watchdog, wc, wget,
        which, who, whoami, xargs, xxd, xz, xzcat, yes, zcat

COMMAND DESCRIPTIONS

acpid	acpid [-df] [-c CONFDIR] [-l LOGFILE] [-a ACTIONFILE] [-M MAPFILE] [-e PROC_EVENT_FILE] [-p PIDFILE] Listen to ACPI events and spawn specific helpers on event arrival `-d Log to stderr, not log file (implies -f) -f Run in foreground -c DIR Config directory [/etc/acpi] -e FILE /proc event file [/proc/acpi/event] -l FILE Log file [/var/log/acpid.log] -p FILE Pid file [/var/run/acpid.pid] -a FILE Action file [/etc/acpid.conf] -M FILE Map file [/etc/acpi.map]` Accept and ignore compatibility options -g -m -s -S -v
adjtimex	adjtimex [-q] [-o OFF] [-f FREQ] [-p TCONST] [-t TICK] Read or set kernel time variables. See adjtimex(2) `-q Quiet -o OFF Time offset, microseconds -f FREQ Frequency adjust, integer kernel units (65536 is 1ppm) -t TICK Microseconds per tick, usually 10000 (positive -t or -f values make clock run faster) -p TCONST`
ar	ar [-o] [-v] [-p] [-t] [-x] ARCHIVE FILES Extract or list FILES from an ar archive `-o Preserve original dates -p Extract to stdout -t List -x Extract -v Verbose`
arch	arch Print system architecture
arp	arp [-vn] [-H HWTYPE] [-i IF] -a [HOSTNAME] [-v] [-i IF] -d HOSTNAME [pub] [-v] [-H HWTYPE] [-i IF] -s HOSTNAME HWADDR [temp] [-v] [-H HWTYPE] [-i IF] -s HOSTNAME HWADDR [netmask MASK] pub [-v] [-H HWTYPE] [-i IF] -Ds HOSTNAME IFACE [netmask MASK] pub Manipulate ARP cache `-a Display (all) hosts -d Delete ARP entry -s Set new entry -v Verbose -n Dont resolve names -i IF Network interface -D Read HWADDR from IFACE -A,-p AF Protocol family -H HWTYPE Hardware address type`
arping	arping [-fqbDUA] [-c CNT] [-w TIMEOUT] [-I IFACE] [-s SRC_IP] DST_IP Send ARP requests/replies `-f Quit on first ARP reply -q Quiet -b Keep broadcasting, dont go unicast -D Exit with 1 if DST_IP replies -U Unsolicited ARP mode, update your neighbors -A ARP answer mode, update your neighbors -c N Stop after sending N ARP requests -w TIMEOUT Seconds to wait for ARP reply -I IFACE Interface to use (default eth0) -s SRC_IP Sender IP address DST_IP Target IP address`
ash	ash [-/+OPTIONS] [-/+o OPT]... [-c ’SCRIPT’ [ARG0 [ARGS]] / FILE [ARGS] / -s [ARGS]] Unix shell interpreter
awk	awk [OPTIONS] [AWK_PROGRAM] [FILE]... `-v VAR=VAL Set variable -F SEP Use SEP as field separator -f FILE Read program from FILE -e AWK_PROGRAM`
basename	basename FILE [SUFFIX] Strip directory path and .SUFFIX from FILE
bc	bc [-sqlw] FILE... Arbitrary precision calculator `-q Quiet -l Load standard math library -s Be POSIX compatible -w Warn if extensions are used` `$BC_LINE_LENGTH` changes output width
blkdiscard	blkdiscard [-o OFS] [-l LEN] [-s] DEVICE Discard sectors on DEVICE `-o OFS Byte offset into device -l LEN Number of bytes to discard -s Perform a secure discard`
blockdev	blockdev OPTION BLOCKDEV `--setro Set ro --setrw Set rw --getro Get ro --getss Get sector size --getbsz Get block size --setbsz BYTES Set block size --getsz Get device size in 512-byte sectors --getsize64 Get device size in bytes --flushbufs Flush buffers --rereadpt Reread partition table`
brctl	brctl COMMAND [BRIDGE [INTERFACE]] Manage ethernet bridges Commands: `addbr BRIDGE Create BRIDGE delbr BRIDGE Delete BRIDGE addif BRIDGE IFACE Add IFACE to BRIDGE delif BRIDGE IFACE Delete IFACE from BRIDGE`
bunzip2	bunzip2 [-cfk] [FILE]... Decompress FILEs (or stdin) `-c Write to stdout -f Force -k Keep input files`
bzcat	bzcat [FILE]... Decompress to stdout
bzip2	bzip2 [OPTIONS] [FILE]... Compress FILEs (or stdin) with bzip2 algorithm `-1..9 Compression level -d Decompress -t Test file integrity -c Write to stdout -f Force -k Keep input files`
cal	cal [-jy] [[MONTH] YEAR] Display a calendar `-j Use julian dates -y Display the entire year`
cat	cat [-nbvteA] [FILE]... Print FILEs to stdout `-n Number output lines -b Number nonempty lines -v Show nonprinting characters as ^x or M-x -t ...and tabs as ^I -e ...and end lines with $ -A Same as -vte`
chgrp	chgrp [-RhLHPcvf]... GROUP FILE... Change the group membership of each FILE to GROUP `-R Recurse -h Affect symlinks instead of symlink targets -L Traverse all symlinks to directories -H Traverse symlinks on command line only -P Dont traverse symlinks (default) -c List changed files -v Verbose -f Hide errors`
chmod	chmod [-Rcvf] MODE[,MODE]... FILE... Each MODE is one or more of the letters ugoa, one of the symbols +-= and one or more of the letters rwxst `-R Recurse -c List changed files -v List all files -f Hide errors`
chown	chown [-RhLHPcvf]... USER[:[GRP]] FILE... Change the owner and/or group of each FILE to USER and/or GRP `-R Recurse -h Affect symlinks instead of symlink targets -L Traverse all symlinks to directories -H Traverse symlinks on command line only -P Dont traverse symlinks (default) -c List changed files -v List all files -f Hide errors`
chpasswd	chpasswd [--md5\|--encrypted\|--crypt-method\|--root] Read user:password from stdin and update /etc/passwd `-e,--encrypted Supplied passwords are in encrypted form -m,--md5 Encrypt using md5, not des -c,--crypt-method ALG des,md5,sha256/512 (default sha256) -R,--root DIR Directory to chroot into`
chroot	chroot NEWROOT [PROG ARGS] Run PROG with root directory set to NEWROOT
chvt	chvt N Change the foreground virtual terminal to /dev/ttyN
clear	clear Clear screen
cmp	cmp [-l] [-s] FILE1 [FILE2 [SKIP1 [SKIP2]]] Compare FILE1 with FILE2 (or stdin) `-l Write the byte numbers (decimal) and values (octal) for all differing bytes -s Quiet`
cp	cp [OPTIONS] SOURCE... DEST Copy SOURCE(s) to DEST `-a Same as -dpR -R,-r Recurse -d,-P Preserve symlinks (default if -R) -L Follow all symlinks -H Follow symlinks on command line -p Preserve file attributes if possible -f Overwrite -i Prompt before overwrite -l,-s Create (sym)links -T Treat DEST as a normal file -u Copy only newer files`
cpio	cpio [-dmvu] [-F FILE] [-R USER[:GRP]] [-H newc] [-tio] [EXTR_FILE]... Extract (-i) or list (-t) files from a cpio archive, or take file list from stdin and create an archive (-o) Main operation mode: `-t List -i Extract EXTR_FILEs (or all) -o Create (requires -H newc) Options: -H newc Archive format -d Make leading directories -m Preserve mtime -v Verbose -u Overwrite -F FILE Input (-t,-i,-p) or output (-o) file -R USER[:GRP] Set owner of created files -L Dereference symlinks -0 Input is separated by NULs`
crond	crond -fbS -l N -L LOGFILE -c DIR `-f Foreground -b Background (default) -S Log to syslog (default) -l N Set log level. Most verbose 0, default 8 -L FILE Log to FILE -c DIR Cron dir. Default:/var/spool/cron/crontabs`
crontab	crontab [-c DIR] [-u USER] [-ler]\|[FILE] `-c Crontab directory -u User -l List crontab -e Edit crontab -r Delete crontab FILE Replace crontab by FILE (-: stdin)`
cttyhack	cttyhack [PROG ARGS] Give PROG a controlling tty if possible. Example for /etc/inittab (for busybox init): ::respawn:/bin/cttyhack /bin/sh Giving controlling tty to shell running with PID 1: $ exec cttyhack sh Starting interactive shell from boot shell script: `setsid cttyhack sh`
cut	cut [OPTIONS] [FILE]... Print selected fields from each input FILE to stdout `-b LIST Output only bytes from LIST -c LIST Output only characters from LIST -d CHAR Use CHAR instead of tab as the field delimiter -s Output only the lines containing delimiter -f N Print only these fields -n Ignored`
date	date [OPTIONS] [+FMT] [TIME] Display time (using +FMT), or set time `[-s,--set] TIME Set time to TIME -u,--utc Work in UTC (dont convert to local time) -R,--rfc-2822 Output RFC-2822 compliant date string -I[SPEC] Output ISO-8601 compliant date string SPEC=date (default) for date only, hours, minutes, or seconds for date and time to the indicated precision -r,--reference FILE Display last modification time of FILE -d,--date TIME Display TIME, not now -D FMT Use FMT for -d TIME conversion` Recognized TIME formats: `hh:mm[:ss] [YYYY.]MM.DD-hh:mm[:ss] YYYY-MM-DD hh:mm[:ss] [[[[[YY]YY]MM]DD]hh]mm[.ss] date TIME form accepts MMDDhhmm[[YY]YY][.ss] instead`
dc	dc [-x] [-eSCRIPT]... [-fFILE]... [FILE]... Tiny RPN calculator. Operations: +, -, , /, %, ~, ^, \|, p - print top of the stack without popping f - print entire stack k - pop the value and set the precision i - pop the value and set input radix o - pop the value and set output radix Examples: dc -e’2 2 + p’ -> 4, dc -e’8 8 2 2 + / p’ -> 16
dd	dd [if=FILE] [of=FILE] [ibs=N obs=N/bs=N] [count=N] [skip=N] [seek=N] [conv=notrunc\|noerror\|sync\|fsync] [iflag=skip_bytes\|fullblock] [oflag=seek_bytes] Copy a file with converting and formatting if=FILE Read from FILE instead of stdin of=FILE Write to FILE instead of stdout bs=N Read and write N bytes at a time ibs=N Read N bytes at a time obs=N Write N bytes at a time count=N Copy only N input blocks skip=N Skip N input blocks seek=N Skip N output blocks conv=notrunc Dont truncate output file conv=noerror Continue after read errors conv=sync Pad blocks with zeros conv=fsync Physically write data out before finishing conv=swab Swap every pair of bytes iflag=skip_bytes skip=N is in bytes iflag=fullblock Read full blocks oflag=seek_bytes seek=N is in bytes status=noxfer Suppress rate output status=none Suppress all output N may be suffixed by c (1), w (2), b (512), kB (1000), k (1024), MB, M, GB, G
deallocvt	deallocvt [N] Deallocate unused virtual terminal /dev/ttyN
depmod	depmod [-n] [-b BASE] [VERSION] [MODFILES]... Generate modules.dep, alias, and symbols files `-b BASE Use BASE/lib/modules/VERSION -n Dry run: print files to stdout`
devmem	devmem ADDRESS [WIDTH [VALUE]] Read/write from physical address `ADDRESS Address to act upon WIDTH Width (8/16/...) VALUE Data to be written`
df	df [-PkmhTai] [-B SIZE] [FILESYSTEM]... Print filesystem usage statistics `-P POSIX output format -k 1024-byte blocks (default) -m 1M-byte blocks -h Human readable (e.g. 1K 243M 2G) -T Print filesystem type -a Show all filesystems -i Inodes -B SIZE Blocksize`
diff	diff [-abBdiNqrTstw] [-L LABEL] [-S FILE] [-U LINES] FILE1 FILE2 Compare files line by line and output the differences between them. This implementation supports unified diffs only. -a Treat all files as text -b Ignore changes in the amount of whitespace -B Ignore changes whose lines are all blank -d Try hard to find a smaller set of changes -i Ignore case differences -L Use LABEL instead of the filename in the unified header -N Treat absent files as empty -q Output only whether files differ -r Recurse -S Start with FILE when comparing directories -T Make tabs line up by prefixing a tab when necessary -s Report when two files are the same -t Expand tabs to spaces in output -U Output LINES lines of context -w Ignore all whitespace
dirname	dirname FILENAME Strip non-directory suffix from FILENAME
dmesg	dmesg [-c] [-n LEVEL] [-s SIZE] Print or control the kernel ring buffer `-c Clear ring buffer after printing -n LEVEL Set console logging level -s SIZE Buffer size -r Print raw message buffer`
dos2unix	dos2unix [-ud] [FILE] Convert FILE in-place from DOS to Unix format. When no file is given, use stdin/stdout. `-u dos2unix -d unix2dos`
dpkg	dpkg [-ilCPru] [-F OPT] PACKAGE Install, remove and manage Debian packages `-i,--install Install the package -l,--list List of installed packages --configure Configure an unpackaged package -P,--purge Purge all files of a package -r,--remove Remove all but the configuration files for a package --unpack Unpack a package, but dont configure it --force-depends Ignore dependency problems --force-confnew Overwrite existing config files when installing --force-confold Keep old config files when installing`
dpkg-deb	dpkg-deb [-cefxX] FILE [DIR] Perform actions on Debian packages (.deb) `-c List files -f Print control fields -e Extract control files to DIR (default: ./DEBIAN) -x Extract files to DIR (no default) -X Verbose -x`
du	du [-aHLdclsxhmk] [FILE]... Summarize disk space used for each FILE and/or directory `-a Show file sizes too -L Follow all symlinks -H Follow symlinks on command line -d N Limit output to directories (and files with -a) of depth < N -c Show grand total -l Count sizes many times if hard linked -s Display only a total for each argument -x Skip directories on different filesystems -h Sizes in human readable format (e.g., 1K 243M 2G) -m Sizes in megabytes -k Sizes in kilobytes (default)`
dumpkmap	dumpkmap > keymap Print a binary keyboard translation table to stdout
dumpleases	dumpleases [-r\|-a] [-d] [-f LEASEFILE] Display DHCP leases granted by udhcpd `-f,--file FILE Lease file -r,--remaining Show remaining time -a,--absolute Show expiration time -d,--decimal Show time in seconds`
echo	echo [-neE] [ARG]... Print the specified ARGs to stdout `-n Suppress trailing newline -e Interpret backslash escapes (i.e., \t=tab) -E Dont interpret backslash escapes (default)`
ed	ed [FILE]
env	env [-iu] [-] [name=value]... [PROG ARGS] Print the current environment or run PROG after setting up the specified environment `-, -i Start with an empty environment -u Remove variable from the environment`
expand	expand [-i] [-t N] [FILE]... Convert tabs to spaces, writing to stdout `-i Dont convert tabs after non blanks -t Tabstops every N chars`
expr	expr EXPRESSION Print the value of EXPRESSION to stdout EXPRESSION may be: ARG1 \| ARG2 ARG1 if it is neither null nor 0, otherwise ARG2 ARG1 & ARG2 ARG1 if neither argument is null or 0, otherwise 0 ARG1 < ARG2 1 if ARG1 is less than ARG2, else 0. Similarly: ARG1 <= ARG2 ARG1 = ARG2 ARG1 != ARG2 ARG1 >= ARG2 ARG1 > ARG2 ARG1 + ARG2 Sum of ARG1 and ARG2. Similarly: ARG1 - ARG2 ARG1 * ARG2 ARG1 / ARG2 ARG1 % ARG2 STRING : REGEXP Anchored pattern match of REGEXP in STRING match STRING REGEXP Same as STRING : REGEXP substr STRING POS LENGTH Substring of STRING, POS counted from 1 index STRING CHARS Index in STRING where any CHARS is found, or 0 length STRING Length of STRING quote TOKEN Interpret TOKEN as a string, even if it is a keyword like match or an operator like / (EXPRESSION) Value of EXPRESSION Beware that many operators need to be escaped or quoted for shells. Comparisons are arithmetic if both ARGs are numbers, else lexicographical. Pattern matches return the string matched between $ and $ or null; if $ and $ are not used, they return the number of characters matched or 0.
factor	factor [NUMBER]... Print prime factors
fallocate	fallocate [-o OFS] -l LEN FILE Preallocate space for FILE `-o OFS Offset of range -l LEN Length of range`
fatattr	fatattr [-+rhsvda] FILE... Change file attributes on FAT filesystem `- Clear attributes + Set attributes r Read only h Hidden s System v Volume label d Directory a Archive`
fdisk	fdisk [-ul] [-C CYLINDERS] [-H HEADS] [-S SECTORS] [-b SSZ] DISK Change partition table `-u Start and End are in sectors (instead of cylinders) -l Show partition table for each DISK, then exit -b 2048 (for certain MO disks) use 2048-byte sectors -C CYLINDERS Set number of cylinders/heads/sectors -H HEADS Typically 255 -S SECTORS Typically 63`
find	find [-HL] [PATH]... [OPTIONS] [ACTIONS] Search for files and perform actions on them. First failed action stops processing of current file. Defaults: PATH is current directory, action is ’-print’ `-L,-follow Follow symlinks -H ...on command line only -xdev Dont descend directories on other filesystems -maxdepth N Descend at most N levels. -maxdepth 0 applies actions to command line arguments only -mindepth N Dont act on first N levels -depth Act on directory after traversing it` Actions: ( ACTIONS ) Group actions for -o / -a ! ACT Invert ACTs success/failure ACT1 [-a] ACT2 If ACT1 fails, stop, else do ACT2 ACT1 -o ACT2 If ACT1 succeeds, stop, else do ACT2 Note: -a has higher priority than -o -name PATTERN Match file name (w/o directory name) to PATTERN -iname PATTERN Case insensitive -name -path PATTERN Match path to PATTERN -ipath PATTERN Case insensitive -path -regex PATTERN Match path to regex PATTERN -type X File type is X (one of: f,d,l,b,c,s,p) -executable File is executable -perm MASK At least one mask bit (+MASK), all bits (-MASK), or exactly MASK bits are set in files mode -mtime DAYS mtime is greater than (+N), less than (-N), or exactly N days in the past -mmin MINS mtime is greater than (+N), less than (-N), or exactly N minutes in the past -newer FILE mtime is more recent than FILEs -inum N File has inode number N -user NAME/ID File is owned by given user -group NAME/ID File is owned by given group -size N[bck] File size is N (c:bytes,k:kbytes,b:512 bytes(def.)) +/-N: file size is bigger/smaller than N -links N Number of links is greater than (+N), less than (-N), or exactly N -prune If current file is directory, dont descend into it If none of the following actions is specified, -print is assumed -print Print file name -print0 Print file name, NUL terminated -exec CMD ARG ; Run CMD with all instances of {} replaced by file name. Fails if CMD exits with nonzero -exec CMD ARG + Run CMD with {} replaced by list of file names -quit Exit
fold	fold [-bs] [-w WIDTH] [FILE]... Wrap input lines in each FILE (or stdin), writing to stdout `-b Count bytes rather than columns -s Break at spaces -w Use WIDTH columns instead of 80`
free	free [-b/k/m/g] Display the amount of free and used system memory
freeramdisk	freeramdisk DEVICE Free all memory used by the specified ramdisk
fsfreeze	fsfreeze --[un]freeze MOUNTPOINT Flush and halt writes to MOUNTPOINT
fstrim	fstrim [OPTIONS] MOUNTPOINT `-o,--offset OFFSET Offset in bytes to discard from -l,--length LEN Bytes to discard -m,--minimum MIN Minimum extent length -v,--verbose Print number of discarded bytes`
ftpget	ftpget [OPTIONS] HOST [LOCAL_FILE] REMOTE_FILE Download a file via FTP `-c Continue previous transfer -v Verbose -u USER Username -p PASS Password -P NUM Port`
ftpput	ftpput [OPTIONS] HOST [REMOTE_FILE] LOCAL_FILE Upload a file to a FTP server `-v Verbose -u USER Username -p PASS Password -P NUM Port number`
getopt	getopt [OPTIONS] [--] OPTSTRING PARAMS `-a Allow long options starting with single - -l LOPT[,...] Long options to recognize -n PROGNAME The name under which errors are reported -o OPTSTRING Short options to recognize -q No error messages on unrecognized options -Q No normal output -s SHELL Set shell quoting conventions -T Version test (exits with 4) -u Dont quote output` Example: O=‘getopt -l bb: — ab:c:: $@‘ \|\| exit 1 eval set — $O while true; do case $1 in -a) echo A; shift;; -b\|--bb) echo B:’$2’; shift 2;; -c) case $2 in ") echo C; shift 2;; ) echo C:’$2’"; shift 2;; esac;; --) shift; break;; ) echo Error; exit 1;; esac done
getty	getty [OPTIONS] BAUD_RATE[,BAUD_RATE]... TTY [TERMTYPE] Open TTY, prompt for login name, then invoke /bin/login `-h Enable hardware RTS/CTS flow control -L Set CLOCAL (ignore Carrier Detect state) -m Get baud rate from modems CONNECT status message -n Dont prompt for login name -w Wait for CR or LF before sending /etc/issue -i Dont display /etc/issue -f ISSUE_FILE Display ISSUE_FILE instead of /etc/issue -l LOGIN Invoke LOGIN instead of /bin/login -t SEC Terminate after SEC if no login name is read -I INITSTR Send INITSTR before anything else -H HOST Log HOST into the utmp file as the hostname` BAUD_RATE of 0 leaves it unchanged
grep	grep [-HhnlLoqvsriwFEz] [-m N] [-A/B/C N] PATTERN/-e PATTERN.../-f FILE [FILE]... Search for PATTERN in FILEs (or stdin) -H Add filename: prefix -h Do not add filename: prefix -n Add line_no: prefix -l Show only names of files that match -L Show only names of files that dont match -c Show only count of matching lines -o Show only the matching part of line -q Quiet. Return 0 if PATTERN is found, 1 otherwise -v Select non-matching lines -s Suppress open and read errors -r Recurse -i Ignore case -w Match whole words only -x Match whole lines only -F PATTERN is a literal (not regexp) -E PATTERN is an extended regexp -z Input is NUL terminated -m N Match up to N times per file -A N Print N lines of trailing context -B N Print N lines of leading context -C N Same as -A N -B N -e PTRN Pattern to match -f FILE Read pattern from file
groups	groups [USER] Print the group memberships of USER or for the current process
gunzip	gunzip [-cfkt] [FILE]... Decompress FILEs (or stdin) `-c Write to stdout -f Force -k Keep input files -t Test file integrity`
gzip	gzip [-cfkdt] [FILE]... Compress FILEs (or stdin) `-d Decompress -t Test file integrity -c Write to stdout -f Force -k Keep input files`
halt	halt [-d DELAY] [-n] [-f] [-w] Halt the system `-d SEC Delay interval -n Do not sync -f Force (dont go through init) -w Only write a wtmp record`
head	head [OPTIONS] [FILE]... Print first 10 lines of each FILE (or stdin) to stdout. With more than one FILE, precede each with a filename header. `-n N[kbm] Print first N lines -n -N[kbm] Print all except N last lines -c [-]N[kbm] Print first N bytes -q Never print headers -v Always print headers` N may be suffixed by k (x1024), b (x512), or m (x1024^2).
hexdump	hexdump [-bcCdefnosvx] [FILE]... Display FILEs (or stdin) in a user specified format `-b 1-byte octal display -c 1-byte character display -d 2-byte decimal display -o 2-byte octal display -x 2-byte hex display -C hex+ASCII 16 bytes per line -v Show all (no dup folding) -e FORMAT_STR Example: 16/1 "%02x\|""\n" -f FORMAT_FILE -n LENGTH Show only first LENGTH bytes -s OFFSET Skip OFFSET bytes`
hostid	hostid Print out a unique 32-bit identifier for the machine
hostname	hostname [OPTIONS] [HOSTNAME \| -F FILE] Get or set hostname or DNS domain name `-s Short -i Addresses for the hostname -d DNS domain name -f Fully qualified domain name -F FILE Use FILEs content as hostname`
httpd	httpd [-ifv[v]] [-c CONFFILE] [-p [IP:]PORT] [-u USER[:GRP]] [-r REALM] [-h HOME] or httpd -d/-e/-m STRING Listen for incoming HTTP requests `-i Inetd mode -f Dont daemonize -v[v] Verbose -p [IP:]PORT Bind to IP:PORT (default *:80) -u USER[:GRP] Set uid/gid after binding to port -r REALM Authentication Realm for Basic Authentication -h HOME Home directory (default .) -c FILE Configuration file (default {/etc,HOME}/httpd.conf) -m STRING MD5 crypt STRING -e STRING HTML encode STRING -d STRING URL decode STRING`
hwclock	hwclock [-r\|--show] [-s\|--hctosys] [-w\|--systohc] [--systz] [--localtime] [-u\|--utc] [-f\|--rtc FILE] Query and set hardware clock (RTC) `-r Show hardware clock time -s Set system time from hardware clock -w Set hardware clock from system time --systz Set in-kernel timezone, correct system time if hardware clock is in local time -u Assume hardware clock is kept in UTC --localtime Assume hardware clock is kept in local time -f FILE Use specified device (e.g. /dev/rtc2)`
i2cdetect	i2cdetect -l \| -F I2CBUS \| [-ya] [-q\|-r] I2CBUS [FIRST LAST] Detect I2C chips `-l List installed buses -F BUS# List functionalities on this bus -y Disable interactive mode -a Force scanning of non-regular addresses -q Use smbus quick write commands for probing (default) -r Use smbus read byte commands for probing FIRST and LAST limit probing range`
i2cdump	i2cdump [-fy] [-r FIRST-LAST] BUS ADDR [MODE] Examine I2C registers `I2CBUS I2C bus number ADDRESS 0x03-0x77 MODE is: b Byte (default) w Word W Word on even register addresses i I2C block s SMBus block c Consecutive byte Append p for SMBus PEC -f Force access -y Disable interactive mode -r Limit the number of registers being accessed`
i2cget	i2cget [-fy] BUS CHIP-ADDRESS [DATA-ADDRESS [MODE]] Read from I2C/SMBus chip registers `I2CBUS I2C bus number ADDRESS 0x03-0x77 MODE is: b Read byte data (default) w Read word data c Write byte/read byte Append p for SMBus PEC -f Force access -y Disable interactive mode`
i2cset	i2cset [-fy] [-m MASK] BUS CHIP-ADDRESS DATA-ADDRESS [VALUE] ... [MODE] Set I2C registers `I2CBUS I2C bus number ADDRESS 0x03-0x77 MODE is: c Byte, no value b Byte data (default) w Word data i I2C block data s SMBus block data Append p for SMBus PEC -f Force access -y Disable interactive mode -r Read back and compare the result -m MASK Mask specifying which bits to write`
id	id [OPTIONS] [USER] Print information about USER or the current user `-u User ID -g Group ID -G Supplementary group IDs -n Print names instead of numbers -r Print real ID instead of effective ID`
ifconfig	ifconfig [-a] interface [address] Configure a network interface `[add ADDRESS[/PREFIXLEN]] [del ADDRESS[/PREFIXLEN]] [[-]broadcast [ADDRESS]] [[-]pointopoint [ADDRESS]] [netmask ADDRESS] [dstaddr ADDRESS] [outfill NN] [keepalive NN] [hw ether\|infiniband ADDRESS] [metric NN] [mtu NN] [[-]trailers] [[-]arp] [[-]allmulti] [multicast] [[-]promisc] [txqueuelen NN] [[-]dynamic] [mem_start NN] [io_addr NN] [irq NN] [up\|down] ...`
ifdown	ifdown [-anmvf] [-i FILE] IFACE... `-a Deconfigure all interfaces -i FILE Use FILE for interface definitions -n Print out what would happen, but dont do it (note: doesnt disable mappings) -m Dont run any mappings -v Print out what would happen before doing it -f Force deconfiguration`
ifup	ifup [-anmvf] [-i FILE] IFACE... `-a Configure all interfaces -i FILE Use FILE instead of /etc/network/interfaces -n Print out what would happen, but dont do it (note: doesnt disable mappings) -m Dont run any mappings -v Print out what would happen before doing it -f Force configuration`
init	init Init is the first process started during boot. It never exits. It (re)spawns children according to /etc/inittab.
insmod	insmod FILE [SYMBOL=VALUE]... Load kernel module
ionice	ionice [-c 1-3] [-n 0-7] [-p PID] [PROG] Change I/O priority and class `-c Class. 1:realtime 2:best-effort 3:idle -n Priority`
ip	ip [OPTIONS] address\|route\|link\|tunnel\|neigh\|rule [ARGS] OPTIONS := -f[amily] inet\|inet6\|link \| -o[neline] ip addr add\|del IFADDR dev IFACE \| show\|flush [dev IFACE] [to PREFIX] ip route list\|flush\|add\|del\|change\|append\|replace\|test ROUTE ip link set IFACE [up\|down] [arp on\|off] [multicast on\|off] [promisc on\|off] [mtu NUM] [name NAME] [qlen NUM] [address MAC] [master IFACE \| nomaster] ip tunnel add\|change\|del\|show [NAME] [mode ipip\|gre\|sit] [remote ADDR] [local ADDR] [ttl TTL] ip neigh show\|flush [to PREFIX] [dev DEV] [nud STATE] ip rule [list] \| add\|del SELECTOR ACTION
ipcalc	ipcalc [OPTIONS] ADDRESS[/PREFIX] [NETMASK] Calculate and display network settings from IP address `-b Broadcast address -n Network address -m Default netmask for IP -p Prefix for IP/NETMASK -h Resolved host name -s No error messages`
ipneigh	ipneigh show\|flush [to PREFIX] [dev DEV] [nud STATE]
kill	kill [-l] [-SIG] PID... Send a signal (default: TERM) to given PIDs `-l List all signal names and numbers`
killall	killall [-l] [-q] [-SIG] PROCESS_NAME... Send a signal (default: TERM) to given processes `-l List all signal names and numbers -q Dont complain if no processes were killed`
klogd	klogd [-c N] [-n] Log kernel messages to syslog `-c N Print to console messages more urgent than prio N (1-8) -n Run in foreground`
last	last Show listing of the last users that logged into the system
less	less [-EFIMmNSRh~] [FILE]... View FILE (or stdin) one screenful at a time `-E Quit once the end of a file is reached -F Quit if entire file fits on first screen -I Ignore case in all searches -M,-m Display status line with line numbers and percentage through the file -N Prefix line number to each line -S Truncate long lines -R Remove color escape codes in input -~ Suppress ~s displayed past EOF`
link	link FILE LINK Create hard LINK to FILE
ln	ln [OPTIONS] TARGET... LINK\|DIR Create a link LINK or DIR/TARGET to the specified TARGET(s) `-s Make symlinks instead of hardlinks -f Remove existing destinations -n Dont dereference symlinks - treat like normal file -b Make a backup of the target (if exists) before link operation -S suf Use suffix instead of ~ when making backup files -T 2nd arg must be a DIR -v Verbose`
loadfont	loadfont < font Load a console font from stdin
loadkmap	loadkmap < keymap Load a binary keyboard translation table from stdin
logger	logger [OPTIONS] [MESSAGE] Write MESSAGE (or stdin) to syslog `-s Log to stderr as well as the system log -t TAG Log using the specified tag (defaults to user name) -p PRIO Priority (numeric or facility.level pair)`
login	login [-p] [-h HOST] [[-f] USER] Begin a new session on the system `-f Dont authenticate (user already authenticated) -h HOST Host user came from (for network logins) -p Preserve environment`
logname	logname Print the name of the current user
logread	logread [-fF] Show messages in syslogd’s circular buffer `-f Output data as log grows -F Same as -f, but dump buffer first`
losetup	losetup [-r] [-o OFS] {-f\|LOOPDEV} FILE - associate loop devices losetup -d LOOPDEV - disassociate losetup -a - show status losetup -f - show next free loop device `-o OFS Start OFS bytes into FILE -r Read-only -f Show/use next free loop device`
ls	ls [-1AaCxdLHRFplinshrSXvctu] [-w WIDTH] [FILE]... List directory contents -1 One column output -a Include entries which start with . -A Like -a, but exclude . and .. -x List by lines -d List directory entries instead of contents -L Follow symlinks -H Follow symlinks on command line -R Recurse -p Append / to dir entries -F Append indicator (one of */=@\|) to entries -l Long listing format -i List inode numbers -n List numeric UIDs and GIDs instead of names -s List allocated blocks -lc List ctime -lu List atime --full-time List full date and time -h Human readable sizes (1K 243M 2G) --group-directories-first -S Sort by size -X Sort by extension -v Sort by version -t Sort by mtime -tc Sort by ctime -tu Sort by atime -r Reverse sort order -w N Format N columns wide --color[={always,never,auto}] Control coloring
lsmod	lsmod List loaded kernel modules
lzcat	lzcat [FILE]... Decompress to stdout
lzma	lzma -d [-cfk] [FILE]... Decompress FILE (or stdin) `-d Decompress -c Write to stdout -f Force -k Keep input files`
lzop	lzop [-cfUvd123456789CF] [FILE]... `-1..9 Compression level -d Decompress -c Write to stdout -f Force -U Delete input files -v Verbose -F Dont store or verify checksum -C Also write checksum of compressed block`
md5sum	md5sum [-c[sw]] [FILE]... Print or check MD5 checksums `-c Check sums against list in FILEs -s Dont output anything, status code shows success -w Warn about improperly formatted checksum lines`
mdev	mdev [-s] mdev -s is to be run during boot to scan /sys and populate /dev. Bare mdev is a kernel hotplug helper. To activate it: echo /sbin/mdev >/proc/sys/kernel/hotplug It uses /etc/mdev.conf with lines [-][ENV=regex;]...DEVNAME UID:GID PERM [>\|=PATH]\|[!] [@\|$\|PROG] where DEVNAME is device name regex, `@major`,minor[-minor2], or environment variable regex. A common use of the latter is to load modules for hotplugged devices: `$MODALIAS=. 0:0 660 @modprobe "$MODALIAS"` If /dev/mdev.seq file exists, mdev will wait for its value to match `$SEQNUM` variable. This prevents plug/unplug races. To activate this feature, create empty /dev/mdev.seq at boot. If /dev/mdev.log file exists, debug log will be appended to it.
microcom	microcom [-d DELAY] [-t TIMEOUT] [-s SPEED] [-X] TTY Copy bytes for stdin to TTY and from TTY to stdout `-d Wait up to DELAY ms for TTY output before sending every next byte to it -t Exit if both stdin and TTY are silent for TIMEOUT ms -s Set serial line to SPEED -X Disable special meaning of NUL and Ctrl-X from stdin`
mkdir	mkdir [OPTIONS] DIRECTORY... Create DIRECTORY `-m MODE Mode -p No error if exists; make parent directories as needed`
mkdosfs	mkdosfs [-v] [-n LABEL] BLOCKDEV [KBYTES] Make a FAT32 filesystem `-v Verbose -n LBL Volume label`
mke2fs	mke2fs [-Fn] [-b BLK_SIZE] [-i INODE_RATIO] [-I INODE_SIZE] [-m RESERVED_PERCENT] [-L LABEL] BLOCKDEV [KBYTES] `-b BLK_SIZE Block size, bytes -F Force -i RATIO Max number of files is filesystem_size / RATIO -I BYTES Inode size (min 128) -L LBL Volume label -m PERCENT Percent of blocks to reserve for admin -n Dry run`
mkfifo	mkfifo [-m MODE] NAME Create named pipe `-m MODE Mode (default a=rw)`
mknod	mknod [-m MODE] NAME TYPE [MAJOR MINOR] Create a special file (block, character, or pipe) `-m MODE Creation mode (default a=rw) TYPE: b Block device c or u Character device p Named pipe (MAJOR MINOR must be omitted)`
mkpasswd	mkpasswd [OPTIONS] [PASSWORD] [SALT] Print crypt(3) hashed PASSWORD `-P,--password-fd N Read password from fd N -m,--method TYPE des,md5,sha256/512 (default sha256) -S,--salt SALT`
mkswap	mkswap [-L LBL] BLOCKDEV [KBYTES] Prepare BLOCKDEV to be used as swap partition `-L LBL Label`
mktemp	mktemp [-dt] [-p DIR] [TEMPLATE] Create a temporary file with name based on TEMPLATE and print its name. TEMPLATE must end with XXXXXX (e.g. [/dir/]nameXXXXXX). Without TEMPLATE, -t tmp.XXXXXX is assumed. `-d Make directory, not file -q Fail silently on errors -t Prepend base directory name to TEMPLATE -p DIR Use DIR as a base directory (implies -t) -u Do not create anything; print a name` Base directory is: -p DIR, else `$TMPDIR`, else /tmp
modinfo	modinfo [-adlpn0] [-F keyword] MODULE `-a Shortcut for -F author -d Shortcut for -F description -l Shortcut for -F license -p Shortcut for -F parm -F keyword Keyword to look for -0 Separate output with NULs`
modprobe	modprobe [-alrqvsDb] MODULE [SYMBOL=VALUE]... `-a Load multiple MODULEs -l List (MODULE is a pattern) -r Remove MODULE (stacks) or do autoclean -q Quiet -v Verbose -s Log to syslog -D Show dependencies -b Apply blacklist to module names too`
more	more [FILE]... View FILE (or stdin) one screenful at a time
mount	mount [OPTIONS] [-o OPT] DEVICE NODE Mount a filesystem. Filesystem autodetection requires /proc. -a Mount all filesystems in fstab -f Dry run -i Dont run mount helper -r Read-only mount -t FSTYPE[,...] Filesystem type(s) -T FILE Read FILE instead of /etc/fstab -O OPT Mount only filesystems with option OPT (-a only) -o OPT: loop Ignored (loop devices are autodetected) [a]sync Writes are [a]synchronous [no]atime Disable/enable updates to inode access times [no]diratime Disable/enable atime updates to directories [no]relatime Disable/enable atime updates relative to modification time [no]dev (Dis)allow use of special device files [no]exec (Dis)allow use of executable files [no]suid (Dis)allow set-user-id-root programs [r]shared Convert [recursively] to a shared subtree [r]slave Convert [recursively] to a slave subtree [r]private Convert [recursively] to a private subtree [un]bindable Make mount point [un]able to be bind mounted [r]bind Bind a file or directory [recursively] to another location move Relocate an existing mount point remount Remount a mounted filesystem, changing flags ro Same as -r There are filesystem-specific -o flags.
mt	mt [-f device] opcode value Control magnetic tape drive operation Available Opcodes: bsf bsfm bsr bss datacompression drvbuffer eof eom erase fsf fsfm fsr fss load lock mkpart nop offline ras1 ras2 ras3 reset retension rewind rewoffline seek setblk setdensity setpart tell unload unlock weof wset
mv	mv [-fin] SOURCE DEST or: mv [-fin] SOURCE... DIRECTORY Rename SOURCE to DEST, or move SOURCE(s) to DIRECTORY `-f Dont prompt before overwriting -i Interactive, prompt before overwrite -n Dont overwrite an existing file`
nameif	nameif [-s] [-c FILE] [IFNAME HWADDR]... Rename network interface while it in the down state. The device with address HWADDR is renamed to IFACE. `-c FILE Configuration file (default: /etc/mactab) -s Log to syslog`
nc	nc [-iN] [-wN] [-l] [-p PORT] [-f FILE\|IPADDR PORT] [-e PROG] Open a pipe to IP:PORT or FILE `-l Listen mode, for inbound connects (use -ll with -e for persistent server) -p PORT Local port -w SEC Connect timeout -i SEC Delay interval for lines sent -f FILE Use file (ala /dev/ttyS0) instead of network -e PROG Run PROG after connect`
netstat	netstat [-ral] [-tuwx] [-en] Display networking information `-r Routing table -a All sockets -l Listening sockets Else: connected sockets -t TCP sockets -u UDP sockets -w Raw sockets -x Unix sockets Else: all socket types -e Other/more information -n Dont resolve names`
nl	nl [OPTIONS] [FILE]... Write FILEs to standard output with line numbers added `-b STYLE Which lines to number - a: all, t: nonempty, n: none -i N Line number increment -s STRING Use STRING as line number separator -v N Start from N -w N Width of line numbers`
nologin	nologin Politely refuse a login
nproc	nproc --all --ignore=N Print number of available CPUs `--all Number of installed CPUs --ignore=N Exclude N CPUs`
nsenter	nsenter [OPTIONS] [PROG [ARGS]] `-t PID Target process to get namespaces from -m[FILE] Enter mount namespace -u[FILE] Enter UTS namespace (hostname etc) -i[FILE] Enter System V IPC namespace -n[FILE] Enter network namespace -p[FILE] Enter pid namespace -U[FILE] Enter user namespace -S UID Set uid in entered namespace -G GID Set gid in entered namespace --preserve-credentials Dont touch uids or gids -r[DIR] Set root directory -w[DIR] Set working directory -F Dont fork before execing PROG`
nslookup	nslookup [-type=QUERY_TYPE] [-debug] HOST [DNS_SERVER] Query DNS about HOST QUERY_TYPE: soa,ns,a,aaaa,cname,mx,txt,ptr,any
nuke	nuke DIR... Remove DIRs
od	od [-abcdfhilovxs] [-t TYPE] [-A RADIX] [-N SIZE] [-j SKIP] [-S MINSTR] [-w WIDTH] [FILE]... Print FILEs (or stdin) unambiguously, as octal bytes by default
openvt	openvt [-c N] [-sw] [PROG ARGS] Start PROG on a new virtual terminal `-c N Use specified VT -s Switch to the VT -w Wait for PROG to exit`
partprobe	partprobe DEVICE... Ask kernel to rescan partition table
passwd	passwd [OPTIONS] [USER] Change USER’s password (default: current user) `-a ALG des,md5,sha256/512 (default sha256) -d Set password to -l Lock (disable) account -u Unlock (enable) account`
paste	paste [OPTIONS] [FILE]... Paste lines from each input file, separated with tab `-d LIST Use delimiters from LIST, not tab -s Serial: one file at a time`
patch	patch [OPTIONS] [ORIGFILE [PATCHFILE]] `-p N Strip N leading components from file names -i DIFF Read DIFF instead of stdin -R Reverse patch -N Ignore already applied patches -E Remove output files if they become empty --dry-run Dont actually change files`
pidof	pidof [NAME]... List PIDs of all processes with names that match NAMEs
ping	ping [OPTIONS] HOST Send ICMP ECHO_REQUEST packets to network hosts -4,-6 Force IP or IPv6 name resolution -c CNT Send only CNT pings -s SIZE Send SIZE data bytes in packets (default 56) -i SECS Interval -A Ping as soon as reply is recevied -t TTL Set TTL -I IFACE/IP Source interface or IP address -W SEC Seconds to wait for the first response (default 10) (after all -c CNT packets are sent) -w SEC Seconds until ping exits (default:infinite) (can exit earlier with -c CNT) -q Quiet, only display output at start and when finished -p HEXBYTE Pattern to use for payload
ping6	ping6 [OPTIONS] HOST Send ICMP ECHO_REQUEST packets to network hosts `-c CNT Send only CNT pings -s SIZE Send SIZE data bytes in packets (default 56) -i SECS Interval -A Ping as soon as reply is recevied -I IFACE/IP Source interface or IP address -q Quiet, only display output at start and when finished -p HEXBYTE Pattern to use for payload`
pivot_root	pivot_root NEW_ROOT PUT_OLD Move the current root file system to PUT_OLD and make NEW_ROOT the new root file system
poweroff	poweroff [-d DELAY] [-n] [-f] Halt and shut off power `-d SEC Delay interval -n Do not sync -f Force (dont go through init)`
printf	printf FORMAT [ARG]... Format and print ARG(s) according to FORMAT (a-la C printf)
ps	ps [-o COL1,COL2=HEADER] [-T] Show list of processes `-o COL1,COL2=HEADER Select columns for display -T Show threads`
pwd	pwd Print the full filename of the current working directory
rdate	rdate [-s/-p] HOST Set and print time from HOST using RFC 868 `-s Only set system time -p Only print time`
readlink	readlink [-fnv] FILE Display the value of a symlink `-f Canonicalize by following all symlinks -n Dont add newline -v Verbose`
realpath	realpath FILE... Return the absolute pathnames of given FILE
reboot	reboot [-d DELAY] [-n] [-f] Reboot the system `-d SEC Delay interval -n Do not sync -f Force (dont go through init)`
renice	renice [-n] PRIORITY [[-p \| -g \| -u] ID...]... Change scheduling priority of a running process `-n Add PRIORITY to current nice value Without -n, nice value is set to PRIORITY -p Process ids (default) -g Process group ids -u Process user names`
reset	reset Reset the screen
resume	resume BLOCKDEV [OFFSET] Restore system state from ’suspend-to-disk’ data in BLOCKDEV
rev	rev [FILE]... Reverse lines of FILE
rm	rm [-irf] FILE... Remove (unlink) FILEs `-i Always prompt before removing -f Never prompt -R,-r Recurse`
rmdir	rmdir [OPTIONS] DIRECTORY... Remove DIRECTORY if it is empty `-p Include parents --ignore-fail-on-non-empty`
rmmod	rmmod [-wfa] [MODULE]... Unload kernel modules `-w Wait until the module is no longer used -f Force unload -a Remove all unused modules (recursively)`
route	route [{add\|del\|delete}] Edit kernel routing tables `-n Dont resolve names -e Display other/more information -A inet{6} Select address family`
rpm	rpm -i PACKAGE.rpm; rpm -qp[ildc] PACKAGE.rpm Manipulate RPM packages Commands: `-i Install package -qp Query package -qpi Show information -qpl List contents -qpd List documents -qpc List config files`
rpm2cpio	rpm2cpio PACKAGE.rpm Output a cpio archive of the rpm file
run-init	run-init [-d CAP,CAP...] [-n] [-c CONSOLE_DEV] NEW_ROOT NEW_INIT [ARGS] Free initramfs and switch to another root fs: chroot to NEW_ROOT, delete all in /, move NEW_ROOT to /, execute NEW_INIT. PID must be 1. NEW_ROOT must be a mountpoint. `-c DEV Reopen stdio to DEV after switch -d CAPS Drop capabilities -n Dry run`
run-parts	run-parts [-a ARG]... [-u UMASK] [--reverse] [--test] [--exit-on-error] DIRECTORY Run a bunch of scripts in DIRECTORY `-a ARG Pass ARG as argument to scripts -u UMASK Set UMASK before running scripts --reverse Reverse execution order --test Dry run --exit-on-error Exit if a script exits with non-zero`
sed	sed [-i[SFX]] [-nrE] [-f FILE]... [-e CMD]... [FILE]... or: sed [-i[SFX]] [-nrE] CMD [FILE]... `-e CMD Add CMD to sed commands to be executed -f FILE Add FILE contents to sed commands to be executed -i[SFX] Edit files in-place (otherwise sends to stdout) Optionally back files up, appending SFX -n Suppress automatic printing of pattern space -r,-E Use extended regex syntax` If no -e or -f, the first non-option argument is the sed command string. Remaining arguments are input files (stdin if none).
seq	seq [-w] [-s SEP] [FIRST [INC]] LAST Print numbers from FIRST to LAST, in steps of INC. FIRST, INC default to 1. `-w Pad to last with leading zeros -s SEP String separator`
setkeycodes	setkeycodes { SCANCODE KEYCODE }... Modify kernel’s scancode-to-keycode map, allowing unusual keyboards to generate usable keycodes. SCANCODE is either xx or e0xx (hexadecimal), KEYCODE is decimal.
setpriv	setpriv [OPTIONS] PROG [ARGS] Run PROG with different privilege settings -d,--dump Show current capabilities --nnp,--no-new-privs Ignore setuid/setgid bits and file capabilities --inh-caps CAP,CAP Set inheritable capabilities --ambient-caps CAP,CAP Set ambient capabilities
setsid	setsid [-c] PROG ARGS Run PROG in a new session. PROG will have no controlling terminal and will not be affected by keyboard signals (^C etc). `-c Set controlling terminal to stdin`
sh	sh [-/+OPTIONS] [-/+o OPT]... [-c ’SCRIPT’ [ARG0 [ARGS]] / FILE [ARGS] / -s [ARGS]] Unix shell interpreter
sha1sum	sha1sum [-c[sw]] [FILE]... Print or check SHA1 checksums `-c Check sums against list in FILEs -s Dont output anything, status code shows success -w Warn about improperly formatted checksum lines`
sha256sum	sha256sum [-c[sw]] [FILE]... Print or check SHA256 checksums `-c Check sums against list in FILEs -s Dont output anything, status code shows success -w Warn about improperly formatted checksum lines`
sha512sum	sha512sum [-c[sw]] [FILE]... Print or check SHA512 checksums `-c Check sums against list in FILEs -s Dont output anything, status code shows success -w Warn about improperly formatted checksum lines`
shred	shred FILE... Overwrite/delete FILEs `-f Chmod to ensure writability -n N Overwrite N times (default 3) -z Final overwrite with zeros -u Remove file`
shuf	shuf [-e\|-i L-H] [-n NUM] [-o FILE] [-z] [FILE\|ARG...] Randomly permute lines `-e Treat ARGs as lines -i L-H Treat numbers L-H as lines -n NUM Output at most NUM lines -o FILE Write to FILE, not standard output -z End lines with zero byte, not newline`
sleep	sleep [N]... Pause for a time equal to the total of the args given, where each arg can have an optional suffix of (s)econds, (m)inutes, (h)ours, or (d)ays
sort	sort [-nrugMcszbdfiokt] [-o FILE] [-k start[.offset][opts][,end[.offset][opts]] [-t CHAR] [FILE]... Sort lines of text `-o FILE Output to FILE -c Check whether input is sorted -b Ignore leading blanks -f Ignore case -i Ignore unprintable characters -d Dictionary order (blank or alphanumeric only) -n Sort numbers -g General numerical sort -M Sort month -V Sort version -t CHAR Field separator -k N[,M] Sort by Nth field -r Reverse sort order -s Stable (dont sort ties alphabetically) -u Suppress duplicate lines -z Lines are terminated by NUL, not newline`
ssl_client	ssl_client [-e] -s FD [-r FD] [-n SNI]
start-stop-daemon	start-stop-daemon [OPTIONS] [-S\|-K] ... [-- ARGS...] Search for matching processes, and then -K: stop all matching processes -S: start a process unless a matching process is found Process matching: -u USERNAME\|UID Match only this users processes -n NAME Match processes with NAME in comm field in /proc/PID/stat -x EXECUTABLE Match processes with this command command in /proc/PID/cmdline -p FILE Match a process with PID from FILE All specified conditions must match -S only: -x EXECUTABLE Program to run -a NAME Zeroth argument -b Background -N N Change nice level -c USER[:[GRP]] Change user/group -m Write PID to pidfile specified by -p -K only: -s SIG Signal to send -t Match only, exit with 0 if found Other: -o Exit with status 0 if nothing is done -v Verbose -q Quiet
stat	stat [OPTIONS] FILE... Display file (default) or filesystem status `-c FMT Use the specified format -f Display filesystem status -L Follow links -t Terse display` FMT sequences for files: %a Access rights in octal %A Access rights in human readable form %b Number of blocks allocated (see %B) %B Size in bytes of each block reported by %b %d Device number in decimal %D Device number in hex %f Raw mode in hex %F File type %g Group ID %G Group name %h Number of hard links %i Inode number %n File name %N File name, with -> TARGET if symlink %o I/O block size %s Total size in bytes %t Major device type in hex %T Minor device type in hex %u User ID %U User name %x Time of last access %X Time of last access as seconds since Epoch %y Time of last modification %Y Time of last modification as seconds since Epoch %z Time of last change %Z Time of last change as seconds since Epoch FMT sequences for file systems: `%a Free blocks available to non-superuser %b Total data blocks %c Total file nodes %d Free file nodes %f Free blocks %i File System ID in hex %l Maximum length of filenames %n File name %s Block size (for faster transfer) %S Fundamental block size (for block counts) %t Type in hex %T Type in human readable form`
strings	strings [-fo] [-t o/d/x] [-n LEN] [FILE]... Display printable strings in a binary file `-f Precede strings with filenames -o Precede strings with octal offsets -t o/d/x Precede strings with offsets in base 8/10/16 -n LEN At least LEN characters form a string (default 4)`
stty	stty [-a\|g] [-F DEVICE] [SETTING]... Without arguments, prints baud rate, line discipline, and deviations from stty sane `-F DEVICE Open device instead of stdin -a Print all current settings in human-readable form -g Print in stty-readable form [SETTING] See manpage`
su	su [-lmp] [-] [-s SH] [USER [SCRIPT ARGS / -c ’CMD’ ARG0 ARGS]] Run shell under USER (by default, root) `-,-l Clear environment, go to home dir, run shell as login shell -p,-m Do not set new $HOME, $SHELL, $USER, $LOGNAME -c CMD Command to pass to sh -c -s SH Shell to use instead of users default`
sulogin	sulogin [-t N] [TTY] Single user login `-t N Timeout`
svc	svc [-udopchaitkx] SERVICE_DIR... Control services monitored by runsv supervisor `-u If service is not running, start it; restart if it stops -d If service is running, send TERM+CONT signals; do not restart it -o Once: if service is not running, start it; do not restart it -pchaitk Send STOP, CONT, HUP, ALRM, INT, TERM, KILL signal to service -x Exit: runsv will exit as soon as the service is down`
svok	svok SERVICE_DIR Check whether runsv supervisor is running. Exit code is 0 if it does, 100 if it does not, 111 (with error message) if SERVICE_DIR does not exist.
swapoff	swapoff [-a] [DEVICE] Stop swapping on DEVICE `-a Stop swapping on all swap devices`
swapon	swapon [-a] [-e] [-d[POL]] [DEVICE] Start swapping on DEVICE `-a Start swapping on all swap devices -d[POL] Discard blocks at swapon (POL=once), as freed (POL=pages), or both (POL omitted) -e Silently skip devices that do not exist`
switch_root	switch_root [-c CONSOLE_DEV] NEW_ROOT NEW_INIT [ARGS] Free initramfs and switch to another root fs: chroot to NEW_ROOT, delete all in /, move NEW_ROOT to /, execute NEW_INIT. PID must be 1. NEW_ROOT must be a mountpoint. `-c DEV Reopen stdio to DEV after switch`
sync	sync [-df] [FILE]... Write all buffered blocks (in FILEs) to disk -d Avoid syncing metadata -f Sync filesystems underlying FILEs
sysctl	sysctl -p [-enq] [FILE...] / [-enqaw] [KEY[=VALUE]]... Show/set kernel parameters `-p Set values from FILEs (default /etc/sysctl.conf) -e Dont warn about unknown keys -n Dont show key names -q Quiet -a Show all values -w Set values`
syslogd	syslogd [OPTIONS] System logging utility (this version of syslogd ignores /etc/syslog.conf) `-n Run in foreground -R HOST[:PORT] Log to HOST:PORT (default PORT:514) -L Log locally and via network (default is network only if -R) -C[size_kb] Log to shared mem buffer (use logread to read it) -O FILE Log to FILE (default: /var/log/messages, stdout if -) -l N Log only messages more urgent than prio N (1-8) -S Smaller output -t Strip client-generated timestamps`
tac	tac [FILE]... Concatenate FILEs and print them in reverse
tail	tail [OPTIONS] [FILE]... Print last 10 lines of each FILE (or stdin) to stdout. With more than one FILE, precede each with a filename header. `-f Print data as file grows -c [+]N[kbm] Print last N bytes -n N[kbm] Print last N lines -n +N[kbm] Start on Nth line and print the rest -q Never print headers -s SECONDS Wait SECONDS between reads with -f -v Always print headers -F Same as -f, but keep retrying` N may be suffixed by k (x1024), b (x512), or m (x1024^2).
tar	tar c\|x\|t [-ZzJjahmvokO] [-f TARFILE] [-C DIR] [FILE]... Create, extract, or list files from a tar file `c Create x Extract t List -f FILE Name of TARFILE (- for stdin/out) -C DIR Change to DIR before operation -v Verbose -O Extract to stdout -m Dont restore mtime -o Dont restore user:group -k Dont replace existing files -Z (De)compress using compress -z (De)compress using gzip -J (De)compress using xz -j (De)compress using bzip2 -a (De)compress using lzma -h Follow symlinks`
taskset	taskset [-p] [HEXMASK] PID \| PROG ARGS Set or get CPU affinity `-p Operate on an existing PID`
tc	tc OBJECT CMD [dev STRING] OBJECT: qdisc\|class\|filter CMD: add\|del\|change\|replace\|show qdisc [handle QHANDLE] [root\|ingress\|parent CLASSID] [[QDISC_KIND] [help\|OPTIONS]] QDISC_KIND := [p\|b]fifo\|tbf\|prio\|cbq\|red\|etc. qdisc show [dev STRING] [ingress] class [classid CLASSID] [root\|parent CLASSID] [[QDISC_KIND] [help\|OPTIONS] ] class show [ dev STRING ] [root\|parent CLASSID] filter [pref PRIO] [protocol PROTO] [root\|classid CLASSID] [handle FILTERID] [[FILTER_TYPE] [help\|OPTIONS]] filter show [dev STRING] [root\|parent CLASSID]
tee	tee [-ai] [FILE]... Copy stdin to each FILE, and also to stdout `-a Append to the given FILEs, dont overwrite -i Ignore interrupt signals (SIGINT)`
telnet	telnet [-a] [-l USER] HOST [PORT] Connect to telnet server `-a Automatic login with $USER variable -l USER Automatic login as USER`
telnetd	telnetd [OPTIONS] Handle incoming telnet connections `-l LOGIN Exec LOGIN on connect -f ISSUE_FILE Display ISSUE_FILE instead of /etc/issue -K Close connection as soon as login exits (normally wait until all programs close slave pty) -p PORT Port to listen on -b ADDR[:PORT] Address to bind to -F Run in foreground -i Inetd mode`
tftp	tftp [OPTIONS] HOST [PORT] Transfer a file from/to tftp server `-l FILE Local FILE -r FILE Remote FILE -g Get file -p Put file -b SIZE Transfer blocks of SIZE octets`
time	time [-vpa] [-o FILE] PROG ARGS Run PROG, display resource usage when it exits `-v Verbose -p POSIX output format -f FMT Custom format -o FILE Write result to FILE -a Append (else overwrite)`
timeout	timeout [-s SIG] SECS PROG ARGS Runs PROG. Sends SIG to it if it is not gone in SECS seconds. Default SIG: TERM.
top	top [-b] [-nCOUNT] [-dSECONDS] Provide a view of process activity in real time. Read the status of all processes from /proc each SECONDS and display a screenful of them. Keys: `N/M/P/T: sort by pid/mem/cpu/time R: reverse sort H: toggle threads Q,^C: exit` Options: `-b Batch mode -n N Exit after N iterations -d N Delay between updates`
touch	touch [-c] [-d DATE] [-t DATE] [-r FILE] FILE... Update the last-modified date on the given FILE[s] `-c Dont create files -h Dont follow links -d DT Date/time to use -t DT Date/time to use -r FILE Use FILEs date/time`
tr	tr [-cds] STRING1 [STRING2] Translate, squeeze, or delete characters from stdin, writing to stdout `-c Take complement of STRING1 -d Delete input characters coded STRING1 -s Squeeze multiple output characters of STRING2 into one character`
traceroute	traceroute [-46FIlnrv] [-f 1ST_TTL] [-m MAXTTL] [-q PROBES] [-p PORT] [-t TOS] [-w WAIT_SEC] [-s SRC_IP] [-i IFACE] [-z PAUSE_MSEC] HOST [BYTES] Trace the route to HOST -4,-6 Force IP or IPv6 name resolution -F Set dont fragment bit -l Display TTL value of the returned packet -n Print numeric addresses -r Bypass routing tables, send directly to HOST -v Verbose -f N First number of hops (default 1) -m N Max number of hops -q N Number of probes per hop (default 3) -p N Base UDP port number used in probes (default 33434) -s IP Source address -i IFACE Source interface -t N Type-of-service in probe packets (default 0) -w SEC Time to wait for a response (default 3) -g IP Loose source route gateway (8 max)
traceroute6	traceroute6 [-nrv] [-m MAXTTL] [-q PROBES] [-p PORT] [-t TOS] [-w WAIT_SEC] [-s SRC_IP] [-i IFACE] HOST [BYTES] Trace the route to HOST `-n Print numeric addresses -r Bypass routing tables, send directly to HOST -v Verbose -m N Max number of hops -q N Number of probes per hop (default 3) -p N Base UDP port number used in probes (default 33434) -s IP Source address -i IFACE Source interface -t N Type-of-service in probe packets (default 0) -w SEC Time wait for a response (default 3)`
truncate	truncate [-c] -s SIZE FILE... Truncate FILEs to the given size `-c Do not create files -s SIZE Truncate to SIZE`
tty	tty Print file name of stdin’s terminal `-s Print nothing, only return exit status`
tunctl	tunctl [-f device] ([-t name] \| -d name) Create or delete tun interfaces `-f name tun device (/dev/net/tun) -t name Create iface name -d name Delete iface name`
ubirename	ubirename UBI_DEVICE OLD_VOLNAME NEW_VOLNAME [OLD2 NEW2]... Rename UBI volumes on UBI_DEVICE
udhcpc	udhcpc [-fbqRB] [-a[MSEC]] [-t N] [-T SEC] [-A SEC/-n] [-i IFACE] [-s PROG] [-p PIDFILE] [-oC] [-r IP] [-V VENDOR] [-F NAME] [-x OPT:VAL]... [-O OPT]... -i IFACE Interface to use (default eth0) -s PROG Run PROG at DHCP events (default /etc/udhcpc/default.script) -p FILE Create pidfile -B Request broadcast replies -t N Send up to N discover packets (default 3) -T SEC Pause between packets (default 3) -A SEC Wait if lease is not obtained (default 20) -n Exit if lease is not obtained -q Exit after obtaining lease -R Release IP on exit -f Run in foreground -b Background if lease is not obtained -S Log to syslog too -a[MSEC] Validate offered address with ARP ping -r IP Request this IP address -o Dont request any options (unless -O is given) -O OPT Request option OPT from server (cumulative) -x OPT:VAL Include option OPT in sent packets (cumulative) Examples of string, numeric, and hex byte opts: -x hostname:bbox - option 12 -x lease:3600 - option 51 (lease time) -x 0x3d:0100BEEFC0FFEE - option 61 (client id) -x 14:"dumpfile" - option 14 (shell-quoted) -F NAME Ask server to update DNS mapping for NAME -V VENDOR Vendor identifier (default udhcp VERSION) -C Dont send MAC as client identifier Signals: USR1 Renew lease USR2 Release lease
udhcpd	udhcpd [-fS] [-I ADDR] [CONFFILE] DHCP server `-f Run in foreground -S Log to syslog too -I ADDR Local address -a MSEC Timeout for ARP ping (default 2000)`
uevent	uevent [PROG [ARGS]] uevent runs PROG for every netlink notification. PROG’s environment contains data passed from the kernel. Typical usage (daemon for dynamic device node creation): # uevent mdev & mdev -s
umount	umount [OPTIONS] FILESYSTEM\|DIRECTORY Unmount file systems `-a Unmount all file systems -r Try to remount devices as read-only if mount is busy -l Lazy umount (detach filesystem) -f Force umount (i.e., unreachable NFS server) -d Free loop device if it has been used -t FSTYPE[,...] Unmount only these filesystem type(s)`
uname	uname [-amnrspvio] Print system information `-a Print all -m The machine (hardware) type -n Hostname -r Kernel release -s Kernel name (default) -p Processor type -v Kernel version -i The hardware platform -o OS name`
uncompress	uncompress [-cf] [FILE]... Decompress .Z file[s] `-c Write to stdout -f Overwrite`
unexpand	unexpand [-fa][-t N] [FILE]... Convert spaces to tabs, writing to stdout `-a Convert all blanks -f Convert only leading blanks -t N Tabstops every N chars`
uniq	uniq [-cdu][-f,s,w N] [INPUT [OUTPUT]] Discard duplicate lines `-c Prefix lines by the number of occurrences -d Only print duplicate lines -u Only print unique lines -i Ignore case -f N Skip first N fields -s N Skip first N chars (after any skipped fields) -w N Compare N characters in line`
unix2dos	unix2dos [-ud] [FILE] Convert FILE in-place from Unix to DOS format. When no file is given, use stdin/stdout. `-u dos2unix -d unix2dos`
unlink	unlink FILE Delete FILE by calling unlink()
unlzma	unlzma [-cfk] [FILE]... Decompress FILE (or stdin) `-c Write to stdout -f Force -k Keep input files`
unshare	unshare [OPTIONS] [PROG [ARGS]] -m,--mount[=FILE] Unshare mount namespace -u,--uts[=FILE] Unshare UTS namespace (hostname etc.) -i,--ipc[=FILE] Unshare System V IPC namespace -n,--net[=FILE] Unshare network namespace -p,--pid[=FILE] Unshare PID namespace -U,--user[=FILE] Unshare user namespace -f,--fork Fork before execing PROG -r,--map-root-user Map current user to root (implies -U) --mount-proc[=DIR] Mount /proc filesystem first (implies -m) --propagation slave\|shared\|private\|unchanged Modify mount propagation in mount namespace --setgroups allow\|deny Control the setgroups syscall in user namespaces
unxz	unxz [-cfk] [FILE]... Decompress FILE (or stdin) `-c Write to stdout -f Force -k Keep input files`
unzip	unzip [-lnojpq] FILE[.zip] [FILE]... [-x FILE...] [-d DIR] Extract FILEs from ZIP archive `-l List contents (with -q for short form) -n Never overwrite files (default: ask) -o Overwrite -j Do not restore paths -p Print to stdout -q Quiet -x FILE Exclude FILEs -d DIR Extract into DIR`
uptime	uptime Display the time since the last boot
usleep	usleep N Pause for N microseconds
uudecode	uudecode [-o OUTFILE] [INFILE] Uudecode a file Finds OUTFILE in uuencoded source unless -o is given
uuencode	uuencode [-m] [FILE] STORED_FILENAME Uuencode FILE (or stdin) to stdout `-m Use base64 encoding per RFC1521`
vconfig	vconfig COMMAND [OPTIONS] Create and remove virtual ethernet devices `add IFACE VLAN_ID rem VLAN_NAME set_flag IFACE 0\|1 VLAN_QOS set_egress_map VLAN_NAME SKB_PRIO VLAN_QOS set_ingress_map VLAN_NAME SKB_PRIO VLAN_QOS set_name_type NAME_TYPE`
vi	vi [OPTIONS] [FILE]... Edit FILE `-c CMD Initial command to run ($EXINIT also available) -R Read-only -H List available features`
w	w Show who is logged on
watch	watch [-n SEC] [-t] PROG ARGS Run PROG periodically `-n Loop period in seconds (default 2) -t Dont print header`
watchdog	watchdog [-t N[ms]] [-T N[ms]] [-F] DEV Periodically write to watchdog device DEV `-T N Reboot after N seconds if not reset (default 60) -t N Reset every N seconds (default 30) -F Run in foreground` Use 500ms to specify period in milliseconds
wc	wc [-cmlwL] [FILE]... Count lines, words, and bytes for each FILE (or stdin) `-c Count bytes -m Count characters -l Count newlines -w Count words -L Print longest line length`
wget	wget [-c\|--continue] [--spider] [-q\|--quiet] [-O\|--output-document FILE] [--header ’header: value’] [-Y\|--proxy on/off] [-P DIR] [-S\|--server-response] [-U\|--user-agent AGENT] URL... Retrieve files via HTTP or FTP `--spider Only check URL existence: $? is 0 if exists -c Continue retrieval of aborted transfer -q Quiet -P DIR Save to DIR (default .) -S Show server response -O FILE Save to FILE (- for stdout) -U STR Use STR for User-Agent header -Y on/off Use proxy`
which	which [COMMAND]... Locate a COMMAND
who	who [-a] Show who is logged on `-a Show all -H Print column headers`
whoami	whoami Print the user name associated with the current effective user id
xargs	xargs [OPTIONS] [PROG ARGS] Run PROG on every item given by stdin `-p Ask user whether to run each command -r Dont run command if input is empty -0 Input is separated by NULs -a FILE Read from FILE instead of stdin -t Print the command on stderr before execution -e[STR] STR stops input processing -n N Pass no more than N args to PROG -s N Pass command line of no more than N bytes -I STR Replace STR within PROG ARGS with input line -P N Run up to N PROGs in parallel -x Exit if size is exceeded`
xxd	xxd [OPTIONS] [FILE] Hex dump FILE (or stdin) `-g N Bytes per group -c N Bytes per line -p Show only hex bytes, assumes -c30 -l LENGTH Show only first LENGTH bytes -s OFFSET Skip OFFSET bytes`
xz	xz -d [-cfk] [FILE]... Decompress FILE (or stdin) `-d Decompress -c Write to stdout -f Force -k Keep input files`
xzcat	xzcat [FILE]... Decompress to stdout
yes	yes [STRING] Repeatedly output a line with STRING, or ’y’
zcat	zcat [FILE]... Decompress to stdout

LIBC NSS

GNU Libc (glibc) uses the Name Service Switch (NSS) to configure the behavior of the C library for the local environment, and to configure how it reads system data, such as passwords and group information. This is implemented using an /etc/nsswitch.conf configuration file, and using one or more of the /lib/libnss_* libraries. BusyBox tries to avoid using any libc calls that make use of NSS. Some applets however, such as login and su, will use libc functions that require NSS.

If you enable CONFIG_USE_BB_PWD_GRP, BusyBox will use internal functions to directly access the /etc/passwd, /etc/group, and /etc/shadow files without using NSS. This may allow you to run your system without the need for installing any of the NSS configuration files and libraries.

When used with glibc, the BusyBox ’networking’ applets will similarly require that you install at least some of the glibc NSS stuff (in particular, /etc/nsswitch.conf, /lib/libnss_dns*, /lib/libnss_files*, and /lib/libresolv*).

Shameless Plug: As an alternative, one could use a C library such as uClibc. In addition to making your system significantly smaller, uClibc does not require the use of any NSS support files or libraries.

MAINTAINER

Denis Vlasenko <vda.linux>

AUTHORS

The following people have contributed code to BusyBox whether they know it or not. If you have written code included in BusyBox, you should probably be listed here so you can obtain your bit of eternal glory. If you should be listed here, or the description of what you have done needs more detail, or is incorrect, please send in an update.

Emanuele Aina <emanuele.aina>
run-parts

Erik Andersen <andersen>


    Tons of new stuff, major rewrite of most of the
    core apps, tons of new apps as noted in header files.
    Lots of tedious effort writing these boring docs that
    nobody is going to actually read.

Laurence Anderson <l.d.anderson>


    rpm2cpio, unzip, get_header_cpio, read_gz interface, rpm

Jeff Angielski <jeff>


    ftpput, ftpget

Edward Betts <edward>


    expr, hostid, logname, whoami

John Beppu <beppu>


    du, nslookup, sort

Brian Candler <B.Candler>


    tiny-ls(ls)

Randolph Chung <tausq>


    fbset, ping, hostname

Dave Cinege <dcinege>


    more(v2), makedevs, dutmp, modularization, auto links file,
    various fixes, Linux Router Project maintenance

Jordan Crouse <jordan>


    ipcalc

Magnus Damm <damm>


    tftp client insmod powerpc support

Larry Doolittle <ldoolitt>


    pristine source directory compilation, lots of patches and fixes.

Glenn Engel <glenne>


    httpd

Gennady Feldman <gfeldman>


    Sysklogd (single threaded syslogd, IPC Circular buffer support,
    logread), various fixes.

Karl M. Hegbloom <karlheg>


    cp_mv.c, the test suite, various fixes to utility.c, &c.

Daniel Jacobowitz <dan>


    mktemp.c

Matt Kraai <kraai>


    documentation, bugfixes, test suite

Stephan Linz <linz>


    ipcalc, Red Hat equivalence

John Lombardo <john>

tr

Glenn McGrath <bug1>


    Common unarchiving code and unarchiving applets, ifupdown, ftpgetput,
    nameif, sed, patch, fold, install, uudecode.
    Various bugfixes, review and apply numerous patches.

Manuel Novoa III <mjn3>


    cat, head, mkfifo, mknod, rmdir, sleep, tee, tty, uniq, usleep, wc, yes,
    mesg, vconfig, make_directory, parse_mode, dirname, mode_string,
    get_last_path_component, simplify_path, and a number trivial libbb routines

    also bug fixes, partial rewrites, and size optimizations in
    ash, basename, cal, cmp, cp, df, du, echo, env, ln, logname, md5sum, mkdir,
    mv, realpath, rm, sort, tail, touch, uname, watch, arith, human_readable,
    interface, dutmp, ifconfig, route

Vladimir Oleynik <dzo>


    cmdedit; xargs(current), httpd(current);
    ports: ash, crond, fdisk, inetd, stty, traceroute, top;
    locale, various fixes
    and irreconcilable critic of everything not perfect.

Bruce Perens <bruce>


    Original author of BusyBox in 1995, 1996. Some of his code can
    still be found hiding here and there...

Tim Riker <Tim>


    bug fixes, member of fan club

Kent Robotti <robotti>


    reset, tons and tons of bug reports and patches.

Chip Rosenthal <chip>, <crosenth>


    wget - Contributed by permission of Covad Communications

Pavel Roskin <proski>


    Lots of bugs fixes and patches.

Gyepi Sam <gyepi>


    Remote logging feature for syslogd

Linus Torvalds <torvalds>


    mkswap, fsck.minix, mkfs.minix

Mark Whitley <markw>


    grep, sed, cut, xargs(previous),
    style-guide, new-applet-HOWTO, bug fixes, etc.

Charles P. Wright <cpwright>


    gzip, mini-netcat(nc)

Enrique Zanardi <ezanardi>


    tarcat (since removed), loadkmap, various fixes, Debian maintenance

Tito Ragusa <farmatito>


    devfsd and size optimizations in strings, openvt and deallocvt.

Paul Fox <pgf>


    vi editing mode for ash, various other patches/fixes

Roberto A. Foglietta <me>


    port: dnsd

Bernhard Reutner-Fischer <rep.dot.nop>


    misc

Mike Frysinger <vapier>


    initial e2fsprogs, printenv, setarch, sum, misc

Jie Zhang <jie.zhang>


    fixed two bugs in msh and hush (exitcode of killed processes)

REFERENCED BY

pivot_root(2)