hush/docs/busybox.pod

# vi: set sw=4 ts=4:

=head1 NAME

busybox - I am BusyBox of Borg.  Unix will be assimilated.

=head1 SYNOPSIS

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

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

=head1 DESCRIPTION

BusyBox is a multi-call binary that combines many common Unix utilities into a
single executable.  Most people will create a link to busybox for each function
they wish to use, and BusyBox will act like whatever it was invoked as.  For
example,

	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 providing it the command to run
on the command line.  For example,

	./busybox ls

will also cause BusyBox to behave as 'ls'. 

BusyBox has been written with size-optimization in mind.  It is very easy to
include or exclude the commands (or features) you want installed.  BusyBox
tries to make itself useful to small systems with limited resources.

=head1 COMMANDS

Currently defined functions include:

basename, cat, chmod, chown, chgrp, chroot, clear, chvt, cp, date,
dd, df, dirname, dmesg, du, dutmp, echo, false, fbset, fdflush, find, free,
freeramdisk, deallocvt, fsck.minix, mkfs.minix, grep, gunzip, gzip,
halt, head, hostid, hostname, init, kill, killall, length, ln, loadacm,
loadfont, loadkmap, ls, lsmod, makedevs, math, mkdir, mkfifo, mknod,
mkswap, mnc, more, mount, mt, mv, nslookup, poweroff, ping, printf, ps,
pwd, reboot, rm, rmdir, rmmod, sed, sh, fdisk, sfdisk, sleep, sort,
sync, syslogd, logger, logname, swapon, swapoff, tail, tar, [, test,
tee, touch, tr, true, tty, umount, uname, uptime, uniq, update,
usleep, wc, whoami, yes, zcat

=head1 COMMON OPTIONS

Most BusyBox commands support the B<--help> option to provide a
terse runtime description of their behavior. 

=over 4

=item basename

Usage: basename [file ...]

Strips directory and suffix from filenames. 

Example: 

	$ basename /usr/local/bin/foo
	foo
	$ basename /usr/local/bin/
	bin

-------------------------------

=item cat

Usage: cat [file ...]

Concatenates files and prints them to the standard output.

Example:

	$ cat /proc/uptime
	110716.72 17.67

-------------------------------

=item chmod

Usage: chmod [B<-R>] MODE[,MODE]... FILE...

Changes file access permissions for the specified file(s) or directory(s).
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
PERISSION for the file(s) or directory(s).

WHO may be chosen from:

	u	the 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	sTickey bit (for directories prevents removing files by non-owners)

Alternately, permissions may be set numerically where the first three
numbers are calculated by adding the octal values:

	4	Read
	2	Write
	1	eXecute

An optional fourth digit may also be used to specify

	4	Set user ID
	2	Set group ID
	1	sTickey bit

Options:

	-R	change files and directories recursively.
 
Example:

	$ 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

-------------------------------

=item chown

Usage: chown [OPTION]...  OWNER[.[GROUP] FILE...

Changes the owner and/or group of each FILE to OWNER and/or GROUP.
 
Options:

	-R	change files and directories recursively

Example:

	$ 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

-------------------------------

=item chgrp

Usage: chgrp [OPTION]... GROUP FILE...

Change the group membership of each FILE to GROUP.
 
Options:

	-R	change files and directories recursively
 
Example:

	$ 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

-------------------------------

=item chroot

Usage: chroot NEWROOT [COMMAND...]

Run COMMAND with root directory set to NEWROOT.
 
Example:

	$ 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*

-------------------------------

=item clear

Clears the screen.

-------------------------------

=item chvt

Usage: chvt N

Change foreground virtual terminal to /dev/ttyN
 
-------------------------------

=item cp

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 possable
        -R      copy directories recursively

-------------------------------

=item date

Usage: date [OPTION]... [+FORMAT]

  or:  date [OPTION] [MMDDhhmm[[CC]YY][.ss]]

Display the current time in the given FORMAT, or set the system date.

Options:

	-R              output RFC-822 compliant date string
	-s              set time described by STRING
	-u              print or set Coordinated Universal Time

Example:

	$ date
	Wed Apr 12 18:52:41 MDT 2000

-------------------------------

=item dd

Usage: dd [if=name] [of=name] [bs=n] [count=n] [skip=n] [seek=n]

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)
 
Example:

	$ dd if=/dev/zero of=/dev/ram1 bs=1M count=4
	4+0 records in
	4+0 records out

-------------------------------

=item df

Usage: df [filesystem ...]

Prints the filesystem space used and space available.

Example:

	$ 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% /

-------------------------------

=item dirname

Usage: dirname NAME

Strip non-directory suffix from file name

Example:

	$ dirname /tmp/foo
	/tmp
	$ dirname /tmp/foo/
	/tmp

-------------------------------

=item dmesg

Usage: dmesg [B<-c>] [B<-n> level] [B<-s> bufsize]
 
Print or controls the kernel ring buffer.

-------------------------------

=item du

Usage: du [OPTION]... [FILE]...

Summarize disk space used for each FILE and/or directory.
Disk space is printed in units of 1k (i.e. 1024 bytes).

Options:

	-l      count sizes many times if hard linked
	-s      display only a total for each argument

Example:

	$ ./busybox 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    .
	 
-------------------------------

=item dutmp

Usage: dutmp [FILE]

Dump utmp file format (pipe delimited) from FILE
or stdin to stdout.

Example:

	$ dutmp /var/run/utmp
	8|7||si|||0|0|0|955637625|760097|0
	2|0|~|~~|reboot||0|0|0|955637625|782235|0
	1|20020|~|~~|runlevel||0|0|0|955637625|800089|0
	8|125||l4|||0|0|0|955637629|998367|0
	6|245|tty1|1|LOGIN||0|0|0|955637630|998974|0
	6|246|tty2|2|LOGIN||0|0|0|955637630|999498|0
	7|336|pts/0|vt00andersen|andersen|:0.0|0|0|0|955637763|0|0
	 
-------------------------------

=item echo

Usage: echo [-neE] [ARG ...]

Prints the specified ARGs to stdout

Options:

	-n      suppress trailing newline
	-e      interpret backslash-escaped characters (i.e. \t=tab etc)
	-E      disable interpretation of backslash-escaped characters

Example:

	$ echo "Erik is cool"
	Erik is cool
	$  echo -e "Erik\nis\ncool"
	Erik
	is
	cool
	$ echo "Erik\nis\ncool"
	Erik\nis\ncool
	 
-------------------------------

=item false

-------------------------------

=item fbset

Usage: fbset [options] [mode]

Show and modify frame buffer device settings

Options:

	-h
	-fb
	-db
	-a
	-i
	-g
	-t
	-accel
	-hsync
	-vsync
	-laced
	-double

Example:

	$ 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

-------------------------------

=item fdflush

Usage: fdflush device

Force floppy disk drive to detect disk change

-------------------------------

=item find

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.
	-print			print the full file name followed by a newline to stdout.

Example:

	$ find / -name /etc/passwd
	/etc/passwd

-------------------------------

=item free

Usage: free

Displays the amount of free and used memory in the system.

Example:

	$ free
		      total         used         free       shared      buffers
	  Mem:       257628       248724         8904        59644        93124
	 Swap:       128516         8404       120112
	Total:       386144       257128       129016

-------------------------------

=item freeramdisk

Usage: freeramdisk DEVICE

Free all memory used by the specified ramdisk.

Example:

	$ freeramdisk /dev/ram2

-------------------------------

=item deallocvt

Usage: deallocvt N

Deallocates unused virtual terminal /dev/ttyN
 
-------------------------------

=item fsck.minix

Usage: fsck.minix [B<-larvsmf>] /dev/name

Performs a consistency check for MINIX filesystems.

OPTIONS:

	-l      Lists all filenames
	-r      Perform interactive repairs
	-a      Perform automatic repairs
	-v      verbose
	-s      Outputs super-block information
	-m      Activates MINIX-like "mode not cleared" warnings
	-f      Force file system check.

-------------------------------

=item mkfs.minix

Usage: mkfs.minix [B<-c> | B<-l> filename] [B<-nXX>] [B<-iXX>] /dev/name [blocks]

Make a MINIX filesystem.

OPTIONS:

	-c              Check the device for bad blocks
	-n [14|30]      Specify the maximum length of filenames
	-i              Specify the number of inodes for the filesystem
	-l FILENAME     Read the bad blocks list from FILENAME
	-v              Make a Minix version 2 filesystem
 
-------------------------------

=item grep

Usage: grep [OPTIONS]... PATTERN [FILE]...

Search for PATTERN in each FILE or standard input.

OPTIONS:

	-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

This version of grep matches full regular expresions.

Example:

	$ 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

-------------------------------

=item gunzip


-------------------------------

=item gzip


-------------------------------

=item halt


-------------------------------

=item head

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.

Options:

	-n NUM          Print first NUM lines instead of first 10

Example:

	$ head -n 2 /etc/passwd
	root:x:0:0:root:/root:/bin/bash
	daemon:x:1:1:daemon:/usr/sbin:/bin/sh

-------------------------------

=item hostid


-------------------------------

=item hostname

Usage: hostname [OPTION] {hostname | B<-F> file}

Get or set the hostname or DNS domain name. If a hostname is given
(or a file with the B<-F> parameter), the host name will be set.

Options:

	-s              Short
	-i              Addresses for the hostname
	-d              DNS domain name
	-F FILE         Use the contents of FILE to specify the hostname

Example:

	$ hostname
	slag 

-------------------------------

=item init


-------------------------------

=item kill

Usage: kill [B<-signal>] process-id [process-id ...]

Send a signal (default is SIGTERM) to the specified process(es).

Options:

	-l      List all signal names and numbers.

Example:

	$ 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

-------------------------------

=item killall

-------------------------------

=item length


-------------------------------

=item ln

Usage: ln [OPTION] TARGET... LINK_NAME|DIRECTORY
Create a link named LINK_NAME or DIRECTORY to the specified TARGET
 
Options:

	-s	make symbolic links instead of hard links
	-f	remove existing destination files
 
Example:

    $ ln -s busybox /tmp/ls
    [andersen@debian busybox]$ ls -l /tmp/ls
    lrwxrwxrwx    1 root     root            7 Apr 12 18:39 ls -> busybox*

-------------------------------

=item loadacm

-------------------------------

=item loadfont

-------------------------------

=item loadkmap

-------------------------------

=item ls

Usage: ls [B<-1acdelnpuxACF>] [filenames...]

Options:

	-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
 
-------------------------------

=item lsmod

Usage: lsmod

Shows information about all loaded modules.

-------------------------------

=item makedevs

-------------------------------

=item math

-------------------------------

=item mkdir

Usage: mkdir [OPTION] DIRECTORY...

Create the DIRECTORY(ies), if they do not already exist

Options:

	-m      set permission mode (as in chmod), not rwxrwxrwx - umask
	-p      no error if dir exists, make parent directories as needed

Example:

	$ 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

-------------------------------

=item mkfifo

-------------------------------

=item mknod

Usage: mknod NAME TYPE MAJOR MINOR

Make block or character special files.

TYPEs include:

	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.

Example:

	$ mknod /dev/fd0 b 2 0 

-------------------------------

=item mkswap

Usage: mkswap [B<-c>] [B<-v0>|B<-v1>] device [block-count]

Prepare a disk partition to be used as a swap partition.

Options:

	-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).
	block-count     Number of block to use (default is entire partition).
 
-------------------------------

=item mnc

-------------------------------

=item more

Usage: more [file ...]

More is a filter for paging through text one screenful at a time.

Example:

	$ dmesg | more
 
-------------------------------

=item mount

Usage:  mount [flags]
        mount [flags] device directory [B<-o> options,more-options]

Flags:

	-a:     Mount all file systems in fstab.
	-o option:      One of many filesystem options, listed below.
	-r:     Mount the filesystem read-only.
	-t filesystem-type:     Specify the filesystem type.
	-w:     Mount for reading and writing (default).

Options for use with the "B<-o>" flag:

	async / sync:   Writes are asynchronous / synchronous.
	dev / nodev:    Allow use of special device files / disallow them.
	exec / noexec:  Allow use of executable files / disallow them.
	loop: Mounts a file via loop device.
	suid / nosuid:  Allow set-user-id-root programs / disallow them.
	remount: Re-mount a currently-mounted filesystem, changing its flags.
	ro / rw: Mount for read-only / read-write.
	There are EVEN MORE flags that are specific to each filesystem.
	You'll have to see the written documentation for those.

Example:

	$ 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
  
-------------------------------

=item mt

-------------------------------

=item mv

Usage: mv SOURCE DEST

   or: mv SOURCE... DIRECTORY

Rename SOURCE to DEST, or move SOURCE(s) to DIRECTORY.

Example:

	$ mv /tmp/foo /bin/bar
 
-------------------------------

=item nslookup

-------------------------------

=item poweroff

-------------------------------

=item ping

Usage: ping [OPTION]... host

Send ICMP ECHO_REQUEST packets to network hosts.

Options:

	-c COUNT        Send only COUNT pings.
	-q              Quiet mode, only displays output at start
                        and when finished.
Example:

	$ 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

-------------------------------

=item printf

-------------------------------

=item ps

-------------------------------

=item pwd

-------------------------------

=item reboot

-------------------------------

=item rm

-------------------------------

=item syslogd

-------------------------------

=item logger

-------------------------------

=item logname

-------------------------------

=item swapon

-------------------------------

=item swapoff

-------------------------------

=item tail

-------------------------------

=item tar

-------------------------------

=item test, [

-------------------------------

=item tee

-------------------------------

=item touch

-------------------------------

=item tr

-------------------------------

=item true

-------------------------------

=item tty

-------------------------------

=item umount

-------------------------------

=item uname

-------------------------------

=item uptime

-------------------------------

=item uniq

-------------------------------

=item update

-------------------------------

=item usleep

-------------------------------

=item wc

-------------------------------

=item whoami

-------------------------------

=item yes

-------------------------------

=item zcat

-------------------------------

=back

=head1 SEE ALSO

textutils(1), shellutils(1), etc...

=head1 MAINTAINER

Erik Andersen <erik@lineo.com>

=head1 AUTHORS

The following people have contributed code to BusyBox whether
they know it or not.

Erik Andersen <erik@lineo.com>

=for html <br>

John Beppu <beppu@lineo.com>

=for html <br>

Brian Candler <B.Candler@pobox.com>

=for html <br>

Randolph Chung <tausq@debian.org>

=for html <br>

Dave Cinege <dcinege@psychosis.com>	

=for html <br>

Bruce Perens <bruce@perens.com>

=for html <br>

Linus Torvalds <torvalds@transmeta.com>

=for html <br>

Charles P. Wright <cpwright@villagenet.com>

=for html <br>

Enrique Zanardi <ezanardi@ull.es>

=for html <br>

Karl M. Hegbloom <karlheg@debian.org>

=for html <br>

=cut