BusyBox - The Swiss Army Knife of Embedded Linux
busybox <applet> [arguments...] # or
<applet> [arguments...] # if symlinked
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.
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.
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.
Currently available applets include:
[, [[, arping, ash, basename, bash, blockdev, bunzip2, bzcat, cat, chgrp, chmod, chown, chroot, chrt, cmp, cp, cttyhack, cut, date, dd, depmod, devmem, df, dirname, dmesg, dnsdomainname, du, echo, egrep, env, expr, false, fbset, fbsplash, fdisk, fgrep, find, grep, gunzip, gzip, halt, head, hostname, httpd, ifconfig, ifplugd, insmod, kill, killall, ln, ls, lsmod, md5sum, microcom, mkdir, mke2fs, mkfs.ext2, mknod, modprobe, more, mount, mv, nbd-client, nc, netstat, nice, ping, pivot_root, poweroff, ps, pwd, rdate, readahead, reboot, renice, rm, rmdir, rmmod, route, sed, setconsole, setsid, sh, sleep, stty, switch_root, sync, tail, tar, telnetd, test, timeout, tr, true, udhcpc, umount, uname, unzip, usleep, vconfig, vi, wget, xargs, yes, zcat, zcip
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, don't go unicast -D Duplicated address detection mode -U Unsolicited ARP mode, update your neighbors -A ARP answer mode, update your neighbors -c N Stop after sending N ARP requests -w TIMEOUT Time to wait for ARP reply, seconds -I IFACE Interface to use (default eth0) -s SRC_IP Sender IP address DST_IP Target IP address
ash [-/+OPTIONS] [-/+o OPT]... [-c 'SCRIPT' [ARG0 [ARGS]] / FILE [ARGS]]
Unix shell interpreter
basename FILE [SUFFIX]
Strip directory path and .SUFFIX from FILE
bash [-/+OPTIONS] [-/+o OPT]... [-c 'SCRIPT' [ARG0 [ARGS]] / FILE [ARGS]]
Unix shell interpreter
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
bunzip2 [-cf] [FILE]...
Decompress FILEs (or stdin)
-c Write to stdout -f Force
bzcat FILE
Decompress to stdout
cat [FILE]...
Concatenate FILEs and print them to stdout
chgrp [-RhLHP]... 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 Don't traverse symlinks (default)
chmod [-R] 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
chown [-RhLHP]... OWNER[<.|:>[GROUP]] FILE...
Change the owner and/or group of each FILE to OWNER and/or GROUP
-R Recurse -h Affect symlinks instead of symlink targets -L Traverse all symlinks to directories -H Traverse symlinks on command line only -P Don't traverse symlinks (default)
chroot NEWROOT [PROG ARGS]
Run PROG with root directory set to NEWROOT
chrt [-prfom] [PRIO] [PID | PROG ARGS]
Change scheduling priority and class for a process
-p Operate on PID -r Set SCHED_RR class -f Set SCHED_FIFO class -o Set SCHED_OTHER class -m Show min/max priorities
cmp [-l] [-s] FILE1 [FILE2]
Compare FILE1 with FILE2 (or stdin)
-l Write the byte numbers (decimal) and values (octal) for all differing bytes -s Quiet
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
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 [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 [OPTIONS] [+FMT] [TIME]
Display time (using +FMT), or set time
[-s,--set] TIME Set time to TIME -u,--utc Work in UTC (don't 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
dd [if=FILE] [of=FILE] [ibs=N] [obs=N] [bs=N] [count=N] [skip=N] | |
[seek=N] [conv=notrunc|noerror|sync|fsync] |
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 Don't truncate output file conv=noerror Continue after read errors conv=sync Pad blocks with zeros conv=fsync Physically write data out before finishing
Numbers may be suffixed by c (x1), w (x2), b (x512), kD (x1000), k (x1024), MD (x1000000), M (x1048576), GD (x1000000000) or G (x1073741824)
depmod [-qfwrsv] MODULE [symbol=value]...
-r Remove MODULE (stacks) or do autoclean -q Quiet -v Verbose -f Force -w Wait for unload -s Report via syslog instead of stderr
devmem ADDRESS [WIDTH [VALUE]]
Read/write from physical address
ADDRESS Address to act upon WIDTH Width (8/16/...) VALUE Data to be written
df [-Pkmh] [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)
dirname FILENAME
Strip non-directory suffix from FILENAME
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
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)
echo [-neE] [ARG]...
Print the specified ARGs to stdout
-n Suppress trailing newline -e Interpret backslash escapes (i.e., \t=tab) -E Don't interpret backslash escapes (default)
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
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.
false
Return an exit code of FALSE (1)
fbset [OPTIONS] [MODE]
Show and modify frame buffer settings
fbsplash -s IMGFILE [-c] [-d DEV] [-i INIFILE] [-f CMD]
-s Image -c Hide cursor -d Framebuffer device (default /dev/fb0) -i Config file (var=value): BAR_LEFT,BAR_TOP,BAR_WIDTH,BAR_HEIGHT BAR_R,BAR_G,BAR_B -f Control pipe (else exit after drawing image) commands: 'NN' (% for progress bar) or 'exit'
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 -S SECTORS
find [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'
-follow Follow symlinks -xdev Don't descend directories on other filesystems -maxdepth N Descend at most N levels. -maxdepth 0 applies actions to command line arguments only -mindepth N Don't act on first N levels -depth Act on directory *after* traversing it
Actions:
( ACTIONS ) Group actions for -o / -a ! ACT Invert ACT's 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,...) -perm MASK At least one mask bit (+MASK), all bits (-MASK), or exactly MASK bits are set in file's 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 FILE's -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, don't 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 -delete Delete current file/directory. Turns on -depth option
grep [-HhnlLoqvsriwFE] [-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 don't 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 -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
gunzip [-cft] [FILE]...
Decompress FILEs (or stdin)
-c Write to stdout -f Force -t Test file integrity
gzip [-cfd] [FILE]...
Compress FILEs (or stdin)
-d Decompress -c Write to stdout -f Force
halt [-d DELAY] [-n] [-f]
Halt the system
-d SEC Delay interval -n Do not sync -f Force (don't go through init)
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 -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).
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 FILE's content as hostname
httpd [-ifv[v]] [-c CONFFILE] [-p [IP:]PORT] [-h HOME] or httpd -d/-e STRING
Listen for incoming HTTP requests
-i Inetd mode -f Don't daemonize -v[v] Verbose -p [IP:]PORT Bind to IP:PORT (default *:80) -h HOME Home directory (default .) -c FILE Configuration file (default {/etc,HOME}/httpd.conf) -e STRING HTML encode STRING -d STRING URL decode STRING
ifconfig [-a] interface [address]
Configure a network interface
[[-]broadcast [ADDRESS]] [[-]pointopoint [ADDRESS]] [netmask ADDRESS] [dstaddr ADDRESS] [hw ether ADDRESS] [metric NN] [mtu NN] [[-]trailers] [[-]arp] [[-]allmulti] [multicast] [[-]promisc] [txqueuelen NN] [[-]dynamic] [up|down] ...
ifplugd [OPTIONS]
Network interface plug detection daemon
-n Don't daemonize -s Don't log to syslog -i IFACE Interface -f/-F Treat link detection error as link down/link up (otherwise exit on error) -a Don't up interface at each link probe -M Monitor creation/destruction of interface (otherwise it must exist) -r PROG Script to run -x ARG Extra argument for script -I Don't exit on nonzero exit code from script -p Don't run script on daemon startup -q Don't run script on daemon quit -l Run script on startup even if no cable is detected -t SECS Poll time in seconds -u SECS Delay before running script after link up -d SECS Delay after link down -m MODE API mode (mii, priv, ethtool, wlan, iff, auto) -k Kill running daemon
insmod [-qfwrsv] MODULE [symbol=value]...
-r Remove MODULE (stacks) or do autoclean -q Quiet -v Verbose -f Force -w Wait for unload -s Report via syslog instead of stderr
kill [-l] [-SIG] PID...
Send a signal (default: TERM) to given PIDs
-l List all signal names and numbers
killall [-l] [-q] [-SIG] PROCESS_NAME...
Send a signal (default: TERM) to given processes
-l List all signal names and numbers -q Don't complain if no processes were killed
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 Don't 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
ls [-1AaCxdLHRFplinsehrSXvctu] [-w WIDTH] [FILE]...
List directory contents
-1 One column output -a Include entries which start with . -A Like -a, but exclude . and .. -C List by columns -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 -e List full date and time -h List sizes in human readable format (1K 243M 2G) -r Sort in reverse order -S Sort by size -X Sort by extension -v Sort by version -c With -l: sort by ctime -t With -l: sort by mtime -u With -l: sort by atime -w N Assume the terminal is N columns wide --color[={always,never,auto}] Control coloring
lsmod [-qfwrsv] MODULE [symbol=value]...
-r Remove MODULE (stacks) or do autoclean -q Quiet -v Verbose -f Force -w Wait for unload -s Report via syslog instead of stderr
md5sum [-c[sw]] [FILE]...
Print or check MD5 checksums
-c Check sums against list in FILEs -s Don't output anything, status code shows success -w Warn about improperly formatted checksum lines
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 [OPTIONS] DIRECTORY...
Create DIRECTORY
-m MODE Mode -p No error if exists; make parent directories as needed
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
mkfs.ext2 [-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
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 and MINOR are ignored)
modprobe [-qfwrsv] MODULE [symbol=value]...
-r Remove MODULE (stacks) or do autoclean -q Quiet -v Verbose -f Force -w Wait for unload -s Report via syslog instead of stderr
more [FILE]...
View FILE (or stdin) one screenful at a time
mount [OPTIONS] [-o OPTS] DEVICE NODE
Mount a filesystem. Filesystem autodetection requires /proc.
-a Mount all filesystems in fstab -f Dry run -r Read-only mount -w Read-write mount (default) -t FSTYPE[,...] Filesystem type(s) -O OPT Mount only filesystems with option OPT (-a only) -o OPT: [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/rw Same as -r/-w
There are filesystem-specific -o flags.
mv [-fin] SOURCE DEST or: mv [-fin] SOURCE... DIRECTORY
Rename SOURCE to DEST, or move SOURCE(s) to DIRECTORY
-f Don't prompt before overwriting -i Interactive, prompt before overwrite -n Don't overwrite an existing file
nbd-client HOST PORT BLOCKDEV
Connect to HOST and provide a network block device on BLOCKDEV
nc [-iN] [-wN] [-l] [-p PORT] [-f FILE|IPADDR PORT] [-e PROG]
Open a pipe to IP:PORT or FILE
-e PROG Run PROG after connect -l Listen mode, for inbound connects (use -l twice with -e for persistent server) -p PORT Local port -w SEC Timeout for connect -i SEC Delay interval for lines sent -f FILE Use file (ala /dev/ttyS0) instead of network
netstat [-ral] [-tuwx] [-enWp]
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 Don't resolve names -W Wide display -p Show PID/program name for sockets
nice [-n ADJUST] [PROG ARGS]
Change scheduling priority, run PROG
-n ADJUST Adjust priority by ADJUST
ping HOST
Send ICMP ECHO_REQUEST packets to network hosts
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 [-d DELAY] [-n] [-f]
Halt and shut off power
-d SEC Delay interval -n Do not sync -f Force (don't go through init)
ps
Show list of processes
w Wide output l Long output
pwd
Print the full filename of the current working directory
rdate [-sp] HOST
Get and possibly set the system date and time from a remote HOST
-s Set the system date and time (default) -p Print the date and time
readahead [FILE]...
Preload FILEs to RAM
reboot [-d DELAY] [-n] [-f]
Reboot the system
-d SEC Delay interval -n Do not sync -f Force (don't go through init)
renice {{-n INCREMENT} | PRIORITY} [[-p | -g | -u] ID...]
Change scheduling priority for a running process
-n Adjust current nice value (smaller is faster) -p Process id(s) (default) -g Process group id(s) -u Process user name(s) and/or id(s)
rm [-irf] FILE...
Remove (unlink) FILEs
-i Always prompt before removing -f Never prompt -R,-r Recurse
rmdir [OPTIONS] DIRECTORY...
Remove DIRECTORY if it is empty
-p Include parents
rmmod [-qfwrsv] MODULE [symbol=value]...
-r Remove MODULE (stacks) or do autoclean -q Quiet -v Verbose -f Force -w Wait for unload -s Report via syslog instead of stderr
route [{add|del|delete}]
Edit kernel routing tables
-n Don't resolve names -e Display other/more information -A inet Select address family
sed [-inr] [-f FILE]... [-e CMD]... [FILE]... or: sed [-inr] CMD [FILE]...
-e CMD Add CMD to sed commands to be executed -f FILE Add FILE contents to sed commands to be executed -i Edit files in-place (else sends result to stdout) -n Suppress automatic printing of pattern space -r 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).
setconsole [-r] [DEVICE]
Redirect system console output to DEVICE (default: /dev/tty)
-r Reset output to /dev/console
setsid PROG ARGS
Run PROG in a new session. PROG will have no controlling terminal
and will not be affected by keyboard signals (Ctrl-C etc).
See setsid(2)
for details.
sh [-/+OPTIONS] [-/+o OPT]... [-c 'SCRIPT' [ARG0 [ARGS]] / FILE [ARGS]]
Unix shell interpreter
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
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
switch_root [-c /dev/console] 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
Write all buffered blocks to disk
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 -n N[kbm] Print last N lines
tar -[cxtzjhmvO] [-X FILE] [-T FILE] [-f TARFILE] [-C DIR] [FILE]...
Create, extract, or list files from a tar file
Operation:
c Create x Extract t List f Name of TARFILE ('-' for stdin/out) C Change to DIR before operation v Verbose z (De)compress using gzip j (De)compress using bzip2 O Extract to stdout h Follow symlinks m Don't restore mtime exclude File to exclude X File with names to exclude T File with names to include
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
test EXPRESSION ]
Check file types, compare values etc. Return a 0/1 exit code depending on logical value of EXPRESSION
timeout [-t SECS] [-s SIG] PROG ARGS
Runs PROG. Sends SIG to it if it is not gone in SECS seconds. Defaults: SECS: 10, SIG: TERM.
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
true
Return an exit code of TRUE (0)
udhcpc [-fbnqvoCRB] [-i IFACE] [-r IP] [-s PROG] [-p PIDFILE] | |
[-V VENDOR] [-x OPT:VAL]... [-O OPT]... |
-i,--interface IFACE Interface to use (default eth0) -p,--pidfile FILE Create pidfile -s,--script PROG Run PROG at DHCP events (default /zcnet.script) -B,--broadcast Request broadcast replies -t,--retries N Send up to N discover packets -T,--timeout N Pause between packets (default 3 seconds) -A,--tryagain N Wait N seconds after failure (default 20) -f,--foreground Run in foreground -b,--background Background if lease is not obtained -n,--now Exit if lease is not obtained -q,--quit Exit after obtaining lease -R,--release Release IP on exit -S,--syslog Log to syslog too -a,--arping Use arping to validate offered address -O,--request-option OPT Request option OPT from server (cumulative) -o,--no-default-options Don't request any options (unless -O is given) -r,--request IP Request this IP address -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) -F,--fqdn NAME Ask server to update DNS mapping for NAME -V,--vendorclass VENDOR Vendor identifier (default 'udhcp VERSION') -C,--clientid-none Don't send MAC as client identifier -v Verbose Signals:
USR1 Renew lease USR2 Release lease
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)
uname [-amnrspv]
Print system information
-a Print all -m The machine (hardware) type -n Hostname -r OS release -s OS name (default) -p Processor type -v OS version
unzip [-opts[modifiers]] FILE[.zip] [LIST] [-x XLIST] [-d DIR]
Extract files from ZIP archives
-l List archive contents (with -q for short form) -n Never overwrite files (default) -o Overwrite -p Send output to stdout -q Quiet -x XLST Exclude these files -d DIR Extract files into DIR
usleep N
Pause for N microseconds
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 [OPTIONS] [FILE]...
Edit FILE
-c Initial command to run ($EXINIT also available) -H Short help regarding available features
wget [-csq] [-O FILE] [-Y on/off] [-P DIR] [-U AGENT] [-T SEC] URL...
Retrieve files via HTTP or FTP
-s Spider mode - only check file existence -c Continue retrieval of aborted transfer -q Quiet -P DIR Save to DIR (default .) -T SEC Network read timeout is SEC seconds -O FILE Save to FILE ('-' for stdout) -U STR Use STR for User-Agent header -Y Use proxy ('on' or 'off')
xargs [OPTIONS] [PROG ARGS]
Run PROG on every item given by stdin
-p Ask user whether to run each command -r Don't run command if input is empty -0 Input is separated by NUL characters -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 -x Exit if size is exceeded
yes [STRING]
Repeatedly output a line with STRING, or 'y'
zcat FILE
Decompress to stdout
zcip [OPTIONS] IFACE SCRIPT
Manage a ZeroConf IPv4 link-local address
-f Run in foreground -q Quit after obtaining address -r 169.254.x.x Request this address first -v Verbose
With no -q, runs continuously monitoring for ARP conflicts, exits only on I/O errors (link down etc)
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.
Denis Vlasenko <vda.linux@googlemail.com>
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@tiscali.it> run-parts
Erik Andersen <andersen@codepoet.org>
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@warwick.ac.uk>
rpm2cpio, unzip, get_header_cpio, read_gz interface, rpm
Jeff Angielski <jeff@theptrgroup.com>
ftpput, ftpget
Edward Betts <edward@debian.org>
expr, hostid, logname, whoami
John Beppu <beppu@codepoet.org>
du, nslookup, sort
Brian Candler <B.Candler@pobox.com>
tiny-ls(ls)
Randolph Chung <tausq@debian.org>
fbset, ping, hostname
Dave Cinege <dcinege@psychosis.com>
more(v2), makedevs, dutmp, modularization, auto links file, various fixes, Linux Router Project maintenance
Jordan Crouse <jordan@cosmicpenguin.net>
ipcalc
Magnus Damm <damm@opensource.se>
tftp client insmod powerpc support
Larry Doolittle <ldoolitt@recycle.lbl.gov>
pristine source directory compilation, lots of patches and fixes.
Glenn Engel <glenne@engel.org>
httpd
Gennady Feldman <gfeldman@gena01.com>
Sysklogd (single threaded syslogd, IPC Circular buffer support, logread), various fixes.
Karl M. Hegbloom <karlheg@debian.org>
cp_mv.c, the test suite, various fixes to utility.c, &c.
Daniel Jacobowitz <dan@debian.org>
mktemp.c
Matt Kraai <kraai@alumni.cmu.edu>
documentation, bugfixes, test suite
Stephan Linz <linz@li-pro.net>
ipcalc, Red Hat equivalence
John Lombardo <john@deltanet.com>
tr
Glenn McGrath <bug1@iinet.net.au>
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@codepoet.org>
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@simtreas.ru>
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@pixar.com>
Original author of BusyBox in 1995, 1996. Some of his code can still be found hiding here and there...
Tim Riker <Tim@Rikers.org>
bug fixes, member of fan club
Kent Robotti <robotti@metconnect.com>
reset, tons and tons of bug reports and patches.
Chip Rosenthal <chip@unicom.com>, <crosenth@covad.com>
wget - Contributed by permission of Covad Communications
Pavel Roskin <proski@gnu.org>
Lots of bugs fixes and patches.
Gyepi Sam <gyepi@praxis-sw.com>
Remote logging feature for syslogd
Linus Torvalds <torvalds@transmeta.com>
mkswap, fsck.minix, mkfs.minix
Mark Whitley <markw@codepoet.org>
grep, sed, cut, xargs(previous), style-guide, new-applet-HOWTO, bug fixes, etc.
Charles P. Wright <cpwright@villagenet.com>
gzip, mini-netcat(nc)
Enrique Zanardi <ezanardi@ull.es>
tarcat (since removed), loadkmap, various fixes, Debian maintenance
Tito Ragusa <farmatito@tiscali.it>
devfsd and size optimizations in strings, openvt and deallocvt.
Paul Fox <pgf@foxharp.boston.ma.us>
vi editing mode for ash, various other patches/fixes
Roberto A. Foglietta <me@roberto.foglietta.name>
port: dnsd
Bernhard Reutner-Fischer <rep.dot.nop@gmail.com>
misc
Mike Frysinger <vapier@gentoo.org>
initial e2fsprogs, printenv, setarch, sum, misc
Jie Zhang <jie.zhang@analog.com>
fixed two bugs in msh and hush (exitcode of killed processes)