This documentation is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details.
You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
For more details see the file COPYING in the source distribution of Linux.
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 fileutils, shellutils, findutils, textutils, grep, gzip, tar, etc. BusyBox provides a fairly complete POSIX environment for any small or embedded system. 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 a kernel, a shell (such as ash), and an editor (such as elvis-tiny or ae).
When you create a link to BusyBox for the function you wish to use, when BusyBox is called using that link it will behave as if the command itself has been invoked.
For example, entering
ln -s ./BusyBox ls ./ls
will cause BusyBox to behave as 'ls' (if the 'ls' command has been compiled into BusyBox).
You can also invoke BusyBox by issuing the command as an argument on the command line. For example, entering
will also cause BusyBox to behave as 'ls'.
Currently defined functions include:
basename, cat, chgrp, chmod, chown, chroot, chvt, clear, cp, cut, date, dc, dd, df, dirname, dmesg, du, dumpkmap, echo, false, fbset, fdflush, find, free, freeramdisk, grep, gunzip, gzip, halt, head, hostname, id, init, insmod, kill, killall, ln, loadfont, loadkmap, logger, ls, lsmod, makedevs, mkdir, mkfifo, mknod, mkswap, more, mount, mv, nc, nslookup, ping, poweroff, ps, pwd, reboot, renice, reset, rm, rmdir, rmmod, sed, setkeycodes, sh, sleep, sort, swapoff, swapon, sync, syslogd, tail, tar, tee, telnet, test, touch, tr, true, tty, umount, uname, uniq, update, uptime, usleep, uudecode, uuencode, wc, which, whoami, yes, zcat, [
Usage: basename FILE [SUFFIX]
Strip directory path and suffixes from FILE. If specified, also removes any trailing SUFFIX.
$ basename /usr/local/bin/foo foo $ basename /usr/local/bin/ bin $ basename /foo/bar.txt .txt bar
Usage: cat [FILE]...
Concatenate FILE(s) and prints them to the standard output.
$ cat /proc/uptime 110716.72 17.67
Usage: chgrp [OPTION]... GROUP FILE...
Change the group membership of each FILE to GROUP.
-R Change files and directories recursively
$ ls -l /tmp/foo -r--r--r-- 1 andersen andersen 0 Apr 12 18:25 /tmp/foo $ chgrp root /tmp/foo $ ls -l /tmp/foo -r--r--r-- 1 andersen root 0 Apr 12 18:25 /tmp/foo
Usage: chmod [-R] MODE[,MODE]... FILE...
Change file access permissions for the specified FILE(s) (or directories). Each MODE is defined by combining the letters for WHO has access to the file, an OPERATOR for selecting how the permissions should be changed, and a PERMISSION for FILE(s) (or directories).
WHO may be chosen from
u User who owns the file g Users in the file's Group o Other users not in the file's group a All users
OPERATOR may be chosen from
+ Add a permission - Remove a permission = Assign a permission
PERMISSION may be chosen from
r Read w Write x Execute (or access for directories) s Set user (or group) ID bit t Sticky bit (for directories prevents removing files by non-owners)
Alternately, permissions can be set numerically where the first three numbers are calculated by adding the octal values, such as
4 Read 2 Write 1 Execute
An optional fourth digit can also be used to specify
4 Set user ID 2 Set group ID 1 Sticky bit
-R Change files and directories recursively.
$ ls -l /tmp/foo -rw-rw-r-- 1 root root 0 Apr 12 18:25 /tmp/foo $ chmod u+x /tmp/foo $ ls -l /tmp/foo -rwxrw-r-- 1 root root 0 Apr 12 18:25 /tmp/foo* $ chmod 444 /tmp/foo $ ls -l /tmp/foo -r--r--r-- 1 root root 0 Apr 12 18:25 /tmp/foo
Usage: chown [OPTION]... OWNER[<.|:>[GROUP] FILE...
Change the owner and/or group of each FILE to OWNER and/or GROUP.
-R Change files and directories recursively
$ ls -l /tmp/foo -r--r--r-- 1 andersen andersen 0 Apr 12 18:25 /tmp/foo $ chown root /tmp/foo $ ls -l /tmp/foo -r--r--r-- 1 root andersen 0 Apr 12 18:25 /tmp/foo $ chown root.root /tmp/foo ls -l /tmp/foo -r--r--r-- 1 root root 0 Apr 12 18:25 /tmp/foo
Usage: chroot NEWROOT [COMMAND...]
Run COMMAND with root directory set to NEWROOT.
$ ls -l /bin/ls lrwxrwxrwx 1 root root 12 Apr 13 00:46 /bin/ls -> /BusyBox $ mount /dev/hdc1 /mnt -t minix $ chroot /mnt $ ls -l /bin/ls -rwxr-xr-x 1 root root 40816 Feb 5 07:45 /bin/ls*
Usage: cp [OPTION]... SOURCE DEST
or: cp [OPTION]... SOURCE... DIRECTORY
Copy SOURCE to DEST, or multiple SOURCE(s) to DIRECTORY.
-a Same as -dpR -d Preserve links -p Preserve file attributes if possible -R Copy directories recursively
Usage: cut [OPTION]... [FILE]...
Print selected fields from each input FILE to standard output.
-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
$ echo "Hello world" | cut -f 1 -d ' ' Hello $ echo "Hello world" | cut -f 2 -d ' ' world
Usage: date [OPTION]... [+FORMAT]
or: date [OPTION] [MMDDhhmm[[CC]YY][.ss]]
Display the current time in the given FORMAT, or set the system date.
-R Output RFC-822 compliant date string -s Set time described by STRING -u Print or set Coordinated Universal Time
$ date Wed Apr 12 18:52:41 MDT 2000
Usage: dc [EXPRESSION]
This is a Tiny RPN calculator that understands the following operations: +, -, /, *, and, or, not, eor. If no arguments are given, dc will process input from stdin.
The behaviour of BusyBox/dc deviates (just a little ;-) from GNU/dc, but this will be remedied in the future.
$ dc 2 2 + 4 $ dc 8 8 \* 2 2 + / 16 $ dc 0 1 and 0 $ dc 0 1 or 1 $ echo 72 9 div 8 mul | dc 64
Usage: dd [OPTION]...
Copy a file, converting and formatting according to options.
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 count=N Copy only N input blocks skip=N Skip N input blocks seek=N Skip N output blocks
Numbers may be suffixed by w (x2), k (x1024), b (x512), or M (x1024^2).
$ dd if=/dev/zero of=/dev/ram1 bs=1M count=4 4+0 records in 4+0 records out
Usage: df [FILE]...
Print the filesystem space used and space available.
$ df Filesystem 1k-blocks Used Available Use% Mounted on /dev/sda3 8690864 8553540 137324 98% / /dev/sda1 64216 36364 27852 57% /boot $ df /dev/sda3 Filesystem 1k-blocks Used Available Use% Mounted on /dev/sda3 8690864 8553540 137324 98% /
Usage: dirname NAME
Strip non-directory suffix from NAME.
$ dirname /tmp/foo /tmp $ dirname /tmp/foo/ /tmp
Usage: dmesg [OPTION]...
Print or control the kernel ring buffer.
-c Clear the ring buffer after printing -n LEVEL Set the console logging level to LEVEL -s BUFSIZE Query ring buffer using a buffer of BUFSIZE
Usage: du [OPTION]... [FILE]...
Summarize the disk space used for each FILE or current directory. Disk space printed in units of 1k (i.e., 1024 bytes).
-l Count sizes many times if hard linked -s Display only a total for each argument
$ du 16 ./CVS 12 ./kernel-patches/CVS 80 ./kernel-patches 12 ./tests/CVS 36 ./tests 12 ./scripts/CVS 16 ./scripts 12 ./docs/CVS 104 ./docs 2417 .
Prints out a binary keyboard translation table to standard output.
$ dumpkmap < keymap
Usage: echo [OPTION]... [ARG]...
Print ARGs to stdout.
-n Suppress trailing newline -e Enable interpretation of escaped characters -E Disable interpretation of escaped characters
$ echo "Erik is cool" Erik is cool $ echo -e "Erik\nis\ncool" Erik is cool $ echo "Erik\nis\ncool" Erik\nis\ncool
Usage: expr EXPRESSION
Prints the value of EXPRESSION to standard output.
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 ARG1 is less than ARG2 ARG1 <= ARG2 ARG1 is less than or equal to ARG2 ARG1 = ARG2 ARG1 is equal to ARG2 ARG1 != ARG2 ARG1 is unequal to ARG2 ARG1 >= ARG2 ARG1 is greater than or equal to ARG2 ARG1 > ARG2 ARG1 is greater than ARG2 ARG1 + ARG2 arithmetic sum of ARG1 and ARG2 ARG1 - ARG2 arithmetic difference of ARG1 and ARG2 ARG1 * ARG2 arithmetic product of ARG1 and ARG2 ARG1 / ARG2 arithmetic quotient of ARG1 divided by ARG2 ARG1 % ARG2 arithmetic remainder of ARG1 divided by 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.
Usage: fbset [OPTION]... [MODE]
Show and modify frame buffer device settings.
-h Display option summary -fb DEVICE Operate on DEVICE -db FILE Use FILE for mode database -g XRES YRES VXRES VYRES DEPTH Set all geometry parameters -t PIXCLOCK LEFT RIGHT UPPER LOWER HSLEN VSLEN Set all timing parameters -xres RES Set visible horizontal resolution -yres RES Set visible vertical resolution
$ fbset mode "1024x768-76" # D: 78.653 MHz, H: 59.949 kHz, V: 75.694 Hz geometry 1024 768 1024 768 16 timings 12714 128 32 16 4 128 4 accel false rgba 5/11,6/5,5/0,0/0 endmode
Usage: find [PATH]... [EXPRESSION]
Search for files in a directory hierarchy. The default PATH is the current directory; default EXPRESSION is '-print'.
EXPRESSION may consist of:
-follow Dereference symbolic links -name PATTERN File name (leading directories removed) matches PATTERN -type X Filetype matches X (where X is one of: f,d,l,b,c,...) -perm PERMS Permissions match any of (+NNN); all of (-NNN); or exactly (NNN) -mtime TIME Modified time is greater than (+N); less than (-N); or exactly (N) days
$ find / -name /etc/passwd /etc/passwd
Displays the amount of free and used system memory.
$ free total used free shared buffers Mem: 257628 248724 8904 59644 93124 Swap: 128516 8404 120112 Total: 386144 257128 129016
Usage: freeramdisk DEVICE
Free all memory used by the ramdisk DEVICE.
$ freeramdisk /dev/ram2
Usage: grep [OPTIONS]... PATTERN [FILE]...
Search for PATTERN in each FILE or stdin.
-h Suppress the prefixing filename on output -i Ignore case distinctions -n Print line number with output lines -q Be quiet. Returns 0 if result was found, 1 otherwise -v Select non-matching lines
This version of grep matches full regular expressions.
$ grep root /etc/passwd root:x:0:0:root:/root:/bin/bash $ grep ^[rR]oo. /etc/passwd root:x:0:0:root:/root:/bin/bash
Usage: gunzip [OPTION]... FILE
Uncompress FILE (or stdin if FILE is '-').
-c Write output to standard output -t Test compressed file integrity
$ ls -la /tmp/BusyBox* -rw-rw-r-- 1 andersen andersen 557009 Apr 11 10:55 /tmp/BusyBox-0.43.tar.gz $ gunzip /tmp/BusyBox-0.43.tar.gz $ ls -la /tmp/BusyBox* -rw-rw-r-- 1 andersen andersen 1761280 Apr 14 17:47 /tmp/BusyBox-0.43.tar
Usage: gzip [OPTION]... FILE
Compress FILE (or stdin if FILE is '-') with maximum compression to FILE.gz (or stdout if FILE is '-').
-c Write output to standard output -d decompress
$ ls -la /tmp/BusyBox* -rw-rw-r-- 1 andersen andersen 1761280 Apr 14 17:47 /tmp/BusyBox-0.43.tar $ gzip /tmp/BusyBox-0.43.tar $ ls -la /tmp/BusyBox* -rw-rw-r-- 1 andersen andersen 554058 Apr 14 17:49 /tmp/BusyBox-0.43.tar.gz
Usage: head [OPTION] FILE...
Print first 10 lines of each FILE to standard output. With more than one FILE, precede each with a header giving the file name. With no FILE, or when FILE is -, read standard input.
-n NUM Print first NUM lines instead of first 10
$ head -n 2 /etc/passwd root:x:0:0:root:/root:/bin/bash daemon:x:1:1:daemon:/usr/sbin:/bin/sh
Usage: hostname [OPTION]... [HOSTNAME|-F FILE]
Get or set the hostname or DNS domain name. If a hostname is given (or a file with the -F parameter), the host name will be set.
-s Short -i Addresses for the hostname -d DNS domain name -F, --file FILE Use the contents of FILE to specify the hostname
$ hostname slag
Usage: id [OPTION]... [USERNAME]
Print information for USERNAME or the current user.
-g Print only the group ID -u Print only the user ID -n print a name instead of a number (with for -ug) -r Print the real user ID instead of the effective ID (with -ug)
$ id uid=1000(andersen) gid=1000(andersen)
Init is the parent of all processes.
This version of init is designed to be run only by the kernel.
BusyBox init doesn't support multiple runlevels. The runlevels field of the /etc/inittab file is completely ignored by BusyBox init. If you want runlevels, use sysvinit.
BusyBox init works just fine without an inittab. If no inittab is found, it has the following default behavior:
If it detects that /dev/console is _not_ a serial console, it will also run:
If you choose to use an /etc/inittab file, the inittab entry format is as follows:
WARNING: This field has a non-traditional meaning for BusyBox init! The id field is used by BusyBox init to specify the controlling tty for the specified process to run on. The contents of this field are appended to "/dev/" and used as-is. There is no need for this field to be unique, although if it isn't you may have strange results. If this field is left blank, the controlling tty is set to the console. Also note that if BusyBox detects that a serial console is in use, then only entries whose controlling tty is either the serial console or /dev/null will be run. BusyBox init does nothing with utmp. We don't need no stinkin' utmp.
Valid actions include: sysinit, respawn, askfirst, wait, once, and ctrlaltdel.
The available actions can be classified into two groups: actions that are run only once, and actions that are re-run when the specified process exits.
Run only-once actions:
'sysinit' is the first item run on boot. init waits until all sysinit actions are completed before continuing. Following the completion of all sysinit actions, all 'wait' actions are run. 'wait' actions, like 'sysinit' actions, cause init to wait until the specified task completes. 'once' actions are asyncronous, therefore, init does not wait for them to complete. 'ctrlaltdel' actions are run immediately before init causes the system to reboot (unmounting filesystems with a 'ctrlaltdel' action is a very good idea).
Run repeatedly actions:
'respawn' actions are run after the 'once' actions. When a process started with a 'respawn' action exits, init automatically restarts it. Unlike sysvinit, BusyBox init does not stop processes from respawning out of control. The 'askfirst' actions acts just like respawn, except that before running the specified process it displays the line "Please press Enter to activate this console." and then waits for the user to press enter before starting the specified process.
Unrecognized actions (like initdefault) will cause init to emit an error message, and then go along with its business. All actions are run in the reverse order from how they appear in /etc/inittab.
# This is run first except when booting in single-user mode. # ::sysinit:/etc/init.d/rcS # /bin/sh invocations on selected ttys # # Start an "askfirst" shell on the console (whatever that may be) ::askfirst:-/bin/sh # Start an "askfirst" shell on /dev/tty2-4 tty2::askfirst:-/bin/sh tty2::askfirst:-/bin/sh tty2::askfirst:-/bin/sh # /sbin/getty invocations for selected ttys # tty4::respawn:/sbin/getty 38400 tty5 tty5::respawn:/sbin/getty 38400 tty6 # Example of how to put a getty on a serial line (for a terminal) # #::respawn:/sbin/getty -L ttyS0 9600 vt100 #::respawn:/sbin/getty -L ttyS1 9600 vt100 # # Example how to put a getty on a modem line. #::respawn:/sbin/getty 57600 ttyS2 # Stuff to do before rebooting ::ctrlaltdel:/bin/umount -a -r ::ctrlaltdel:/sbin/swapoff
Usage: insmod [OPTION]... MODULE [symbol=value]...
Load MODULE into the kernel.
-f Force module to load into the wrong kernel version. -k Make module autoclean-able. -v Verbose output -x Do not export externs -L Prevent simultaneous loads of the same module
Usage: kill [OPTION] PID...
Send a signal (default is SIGTERM) to the specified PID(s).
-l List all signal names and numbers -SIG Send signal SIG
$ ps | grep apache 252 root root S [apache] 263 www-data www-data S [apache] 264 www-data www-data S [apache] 265 www-data www-data S [apache] 266 www-data www-data S [apache] 267 www-data www-data S [apache] $ kill 252
Usage: killall [OPTION] NAME...
Send a signal (default is SIGTERM) to the specified NAME(s).
-l List all signal names and numbers -SIG Send signal SIG
$ killall apache
Usage: ln [OPTION]... TARGET FILE|DIRECTORY
Create a link named FILE or DIRECTORY to the specified TARGET. You may use '--' to indicate that all following arguments are non-options.
-s Make symbolic link instead of hard link -f Remove existing destination file
$ ln -s BusyBox /tmp/ls $ ls -l /tmp/ls lrwxrwxrwx 1 root root 7 Apr 12 18:39 ls -> BusyBox*
Load a binary keyboard translation table from stdin.
$ loadkmap < /etc/i18n/lang-keymap
Usage: logger [OPTION]... [MESSAGE]
Write MESSAGE to the system log. If MESSAGE is omitted, log stdin.
-s Log to stderr as well as the system log -t Log using the specified tag (defaults to user name) -p Enter the message with the specified priority This may be numerical or a ``facility.level'' pair
$ logger "hello"
Usage: ls [OPTION]... [FILE]...
-a Do not hide entries starting with . -c With -l: show ctime (the time of last modification of file status information) -d List directory entries instead of contents -e List both full date and full time -l Use a long listing format -n List numeric UIDs and GIDs instead of names -p Append indicator (one of /=@|) to entries -u With -l: show access time (the time of last access of the file) -x List entries by lines instead of by columns -A Do not list implied . and .. -C List entries by columns -F Append indicator (one of */=@|) to entries -L list entries pointed to by symbolic links -R List subdirectories recursively
Usage: md5sum [OPTION]... FILE...
Print or check MD5 checksums.
-b Read files in binary mode -c Check MD5 sums against given list -t Read files in text mode (default) -g Read a string
The following two options are useful only when verifying checksums:
-s Don't output anything, status code shows success -w Warn about improperly formated MD5 checksum lines
$ md5sum busybox 6fd11e98b98a58f64ff3398d7b324003 busybox $ md5sum -c 6fd11e98b98a58f64ff3398d7b324003 busybox 6fd11e98b98a58f64ff3398d7b324002 busybox md5sum: MD5 check failed for 'busybox' ^D
Usage: mkdir [OPTION]... DIRECTORY...
Create the DIRECTORY(s), if they do not already exist.
-m Set permission mode (as in chmod), not rwxrwxrwx - umask -p No error if directory exists, make parent directories as needed
$ mkdir /tmp/foo $ mkdir /tmp/foo /tmp/foo: File exists $ mkdir /tmp/foo/bar/baz /tmp/foo/bar/baz: No such file or directory $ mkdir -p /tmp/foo/bar/baz
Usage: mkfifo [OPTION] NAME
Create a named pipe (identical to 'mknod NAME p').
-m MODE Create the pipe using the specified mode (default a=rw)
Usage: mknod [OPTION]... NAME TYPE MAJOR MINOR
Create a special file (block, character, or pipe).
-m Create the special file using the specified mode (default a=rw)
TYPE may be:
b Make a block (buffered) device c or u Make a character (un-buffered) device p Make a named pipe. MAJOR and MINOR are ignored for named pipes
$ mknod /dev/fd0 b 2 0 $ mknod -m 644 /tmp/pipe p
Usage: mkswap [OPTION]... DEVICE [BLOCKS]
Prepare a disk partition to be used as a swap partition.
-c Check for read-ability. -v0 Make version 0 swap [max 128 Megs]. -v1 Make version 1 swap [big!] (default for kernels > 2.1.117). BLOCKS Number of block to use (default is entire partition).
Usage: mount [OPTION]...
or: mount [OPTION]... DEVICE DIRECTORY
-a Mount all filesystems in /etc/fstab -o One of the many filesystem options listed below -r Mount the filesystem read-only -t TYPE Specify the filesystem type -w Mount the filesystem read-write
Options for use with the -o flag:
async/sync Writes are asynchronous / synchronous atime/noatime Enable / disable updates to inode access times dev/nodev Allow / disallow use of special device files exec/noexec Allow / disallow use of executable files loop Mount a file via loop device suid/nosuid Allow / disallow set-user-id-root programs remount Remount a currently mounted filesystem ro/rw Mount filesystem read-only / read-write
There are even more flags that are filesystem specific. You'll have to see the written documentation for those.
$ mount /dev/hda3 on / type minix (rw) proc on /proc type proc (rw) devpts on /dev/pts type devpts (rw) $ mount /dev/fd0 /mnt -t msdos -o ro $ mount /tmp/diskimage /opt -t ext2 -o loop
Usage: mv SOURCE DEST
or: mv SOURCE... DIRECTORY
Rename SOURCE to DEST, or move SOURCE(s) to DIRECTORY.
$ mv /tmp/foo /bin/bar
Usage: nc HOST PORT
or: nc -p PORT -l
Open a pipe to HOST:PORT or listen for a connection on PORT.
$ nc foobar.somedomain.com 25 220 foobar ESMTP Exim 3.12 #1 Sat, 15 Apr 2000 00:03:02 -0600 help 214-Commands supported: 214- HELO EHLO MAIL RCPT DATA AUTH 214 NOOP QUIT RSET HELP quit 221 foobar closing connection
Usage: nslookup [HOST]
Query the nameserver for the IP address of the given HOST.
$ nslookup localhost Server: default Address: default Name: debian Address: 127.0.0.1
Usage: ping [OPTION]... HOST
Send ICMP ECHO_REQUEST packets to HOST.
-c COUNT Send only COUNT pings -s SIZE Send SIZE data bytes in packets (default=56) -q Quiet mode, only displays output at start and when finished
$ ping localhost PING slag (127.0.0.1): 56 data bytes 64 bytes from 127.0.0.1: icmp_seq=0 ttl=255 time=20.1 ms --- debian ping statistics --- 1 packets transmitted, 1 packets received, 0% packet loss round-trip min/avg/max = 20.1/20.1/20.1 ms
Shut down the system, and request that the kernel turn off power upon halting.
Report process status. This version of ps accepts no options.
$ ps PID Uid Gid State Command 1 root root S init 2 root root S [kflushd] 3 root root S [kupdate] 4 root root S [kpiod] 5 root root S [kswapd] 742 andersen andersen S [bash] 743 andersen andersen S -bash 745 root root S [getty] 2990 andersen andersen R ps
Usage: renice priority pid [pid ...]
Changes priority of running processes. Allowed priorities range from 20 (the process runs only when nothing else is running) to 0 (default priority) to -20 (almost nothing else ever gets to run).
Usage: rm [OPTION]... FILE...
Remove (unlink) the FILE(s). You may use '--' to indicate that all following arguments are non-options.
-i Always prompt before removing each destinations -f Remove existing destinations, never prompt -r or -R Remove the contents of directories recursively
$ rm -rf /tmp/foo
Usage: rmmod [OPTION]... [MODULE]...
Unload MODULE(s) from the kernel.
-a Try to remove all unused kernel modules
$ rmmod tulip
Usage: sed [OPTION]... SCRIPT [FILE]...
Allowed sed scripts come in the following form:
ADDR [!] COMMAND
ADDR can be:
NUMBER Match specified line number $ Match last line /REGEXP/ Match specified regexp
! inverts the meaning of the match
COMMAND can be:
s/regexp/replacement/[igp] which attempt to match regexp against the pattern space and if successful replaces the matched portion with replacement. aTEXT which appends TEXT after the pattern space
This version of sed matches full regular expressions.
-e Add the script to the commands to be executed -n Suppress automatic printing of pattern space
$ echo "foo" | sed -e 's/f[a-zA-Z]o/bar/g' bar
Usage: setkeycodes SCANCODE KEYCODE ...
Set entries into the kernel's scancode-to-keycode map, allowing unusual keyboards to generate usable keycodes.
SCANCODE may be either xx or e0xx (hexadecimal), and KEYCODE is given in decimal.
$ setkeycodes e030 127
lash -- the BusyBox LAme SHell (command interpreter)
This command does not yet have proper documentation.
Use lash just as you would use any other shell. It properly handles pipes, redirects, job control, can be used as the shell for scripts (#!/bin/sh), and has a sufficient set of builtins to do what is needed. It does not (yet) support Bourne Shell syntax. If you need things like ``if-then-else'', ``while'', and such, use ash or bash. If you just need a very simple and extremely small shell, this will do the job.
Usage: sort [OPTION]... [FILE]...
Sort lines of text in FILE(s).
-n Compare numerically -r Reverse after sorting
$ echo -e "e\nf\nb\nd\nc\na" | sort a b c d e f
Usage: swapoff [OPTION] [DEVICE]
Stop swapping virtual memory pages on DEVICE.
-a Stop swapping on all swap devices
Usage: swapon [OPTION] [DEVICE]
Start swapping virtual memory pages on the given device.
-a Start swapping on all swap devices
Usage: syslogd [OPTION]...
Linux system and kernel (provides klogd) logging utility. Note that this version of syslogd/klogd ignores /etc/syslog.conf.
-m NUM Interval between MARK lines (default=20min, 0=off) -n Run as a foreground process -K Do not start up the klogd process -O FILE Use an alternate log file (default=/var/log/messages) -R HOST[:PORT] Log remotely to IP or hostname on PORT (default PORT=514/UDP) -L Log locally as well as network logging (default is network only)
$ syslogd -R masterlog:514 $ syslogd -R 192.168.1.1:601
Usage: tail [OPTION] [FILE]...
Print last 10 lines of each FILE to standard output. With more than one FILE, precede each with a header giving the file name. With no FILE, or when FILE is -, read stdin.
-n NUM Print last NUM lines instead of last 10 -f Output data as the file grows. This version of 'tail -f' supports only one file at a time.
$ tail -n 1 /etc/resolv.conf nameserver 10.0.0.1
Usage: tar [MODE] [OPTION] [FILE]...
MODE may be chosen from
c Create x Extract t List
f FILE Use FILE for tarfile (or stdin if '-') O Extract to stdout exclude FILE File to exclude v List files processed
$ zcat /tmp/tarball.tar.gz | tar -xf - $ tar -cf /tmp/tarball.tar /usr/local
Usage: tee [OPTION]... [FILE]...
Copy stdin to FILE(s), and also to stdout.
-a Append to the given FILEs, do not overwrite
$ echo "Hello" | tee /tmp/foo Hello $ cat /tmp/foo Hello
Usage: telnet HOST [PORT]
Establish interactive communication with another computer over a network using the TELNET protocol.
Usage: test EXPRESSION
or: [ EXPRESSION ]
Check file types and compare values returning an exit code determined by the value of EXPRESSION.
$ test 1 -eq 2 $ echo $? 1 $ test 1 -eq 1 $ echo $? 0 $ [ -d /etc ] $ echo $? 0 $ [ -d /junk ] $ echo $? 1
Usage: touch [OPTION]... FILE...
Update the last-modified date on (or create) FILE(s).
-c Do not create files
$ ls -l /tmp/foo /bin/ls: /tmp/foo: No such file or directory $ touch /tmp/foo $ ls -l /tmp/foo -rw-rw-r-- 1 andersen andersen 0 Apr 15 01:11 /tmp/foo
Usage: tr [OPTION]... STRING1 [STRING2]
Translate, squeeze, and/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
$ echo "gdkkn vnqkc" | tr [a-y] [b-z] hello world
Print the file name of the terminal connected to stdin.
-s Print nothing, only return an exit status
$ tty /dev/tty2
Usage: umount [OPTION]... DEVICE|DIRECTORY
-a Unmount all file systems -r Try to remount devices as read-only if mount is busy -f Force filesystem umount (i.e., unreachable NFS server) -l Do not free loop device (if a loop device has been used)
$ umount /dev/hdc1
Usage: uname [OPTION]...
Print certain system information. With no OPTION, same as -s.
-a Print all information -m Print the machine (hardware) type -n Print the machine's network node hostname -r Print the operating system release -s Print the operating system name -p Print the host processor type -v Print the operating system version
$ uname -a Linux debian 2.2.15pre13 #5 Tue Mar 14 16:03:50 MST 2000 i686 unknown
Usage: uniq [INPUT [OUTPUT]]
Discard all but one of successive identical lines from INPUT (or stdin), writing to OUTPUT (or stdout).
-c prefix lines by the number of occurrences -d only print duplicate lines -u only print unique lines
$ echo -e "a\na\nb\nc\nc\na" | sort | uniq a b c
Usage: update [OPTION]...
Periodically flush filesystem buffers.
-S Force use of sync(2) instead of flushing -s SECS Call sync this often (default 30) -f SECS Flush some buffers this often (default 5)
Display how long the system has been running since boot.
$ uptime 1:55pm up 2:30, load average: 0.09, 0.04, 0.00
Usage: wc [OPTION]... [FILE]...
Print line, word, and byte counts for each FILE, and a total line if more than one FILE is specified. With no FILE, read stdin.
-c Print the byte counts -l Print the newline counts -L Print the length of the longest line -w Print the word counts
$ wc /etc/passwd 31 46 1365 /etc/passwd
Print the user name associated with the current effective user id.
$ whoami andersen
Usage: xargs [OPTIONS] [COMMAND] [ARGS...]
Executes COMMAND on every item given by standard input.
-t Print the command just before it is run
$ ls | xargs gzip $ find . -name '*.c' -print | xargs rm
GNU Libc 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. BusyBox has made it Policy that it will never use NSS, and will never use libc calls that make use of NSS. This allows you to run an embedded system without the need for installing an /etc/nsswitch.conf file and without /lib/libnss_* libraries installed.
If you are using a system that is using a remote LDAP server for authentication via GNU libc NSS, and you want to use BusyBox, then you will need to adjust the BusyBox source. Chances are though, that if you have enough space to install of that stuff on your system, then you probably want the full GNU utilities.
The following people have made significant contributions to BusyBox -- whether they know it or not.
Erik Andersen <email@example.com>
Edward Betts <firstname.lastname@example.org>
John Beppu <email@example.com>
Brian Candler <B.Candler@pobox.com>
Randolph Chung <firstname.lastname@example.org>
Dave Cinege <email@example.com>
Karl M. Hegbloom <firstname.lastname@example.org>
Daniel Jacobowitz <email@example.com>
Matt Kraai <firstname.lastname@example.org>
John Lombardo <email@example.com>
Glenn McGrath <firstname.lastname@example.org>
Bruce Perens <email@example.com>
Chip Rosenthal <firstname.lastname@example.org>, <email@example.com>
Pavel Roskin <firstname.lastname@example.org>
Gyepi Sam <email@example.com>
Linus Torvalds <firstname.lastname@example.org>
Mark Whitley <email@example.com>
Charles P. Wright <firstname.lastname@example.org>
Enrique Zanardi <email@example.com>