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:
[, [[, arp, arping, ash, basename, brctl, cat, chmod, cp, cut, date,
dd, devmem, df, dmesg, echo, expr, false, free, getty, grep, gunzip,
gzip, halt, head, ifconfig, init, insmod, kill, killall, klogd, ln,
logger, login, logread, ls, lsmod, lsof, md5sum, mkdir, mount, mv,
netstat, ping, poweroff, ps, reboot, rm, rmmod, route, sed, sh,
sleep, sync, sysctl, syslogd, tail, tar, telnetd, test, tftp, top,
touch, true, udhcpc, umount, uname, uptime, usleep, vconfig, xargs,
zcat
| 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
-s Set new ARP entry
-d Delete a specified entry
-v Verbose
-n Don't resolve names
-i IF Network interface
-D Read <hwaddr> from given device
-A,-p AF Protocol family
-H HWTYPE Hardware address type
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
brctl COMMAND [BRIDGE [INTERFACE]]
Manage ethernet bridges
Commands:
show Show a list of bridges
addbr BRIDGE Create BRIDGE
delbr BRIDGE Delete BRIDGE
addif BRIDGE IFACE Add IFACE to BRIDGE
delif BRIDGE IFACE Delete IFACE from BRIDGE
setageing BRIDGE TIME Set ageing time
setfd BRIDGE TIME Set bridge forward delay
sethello BRIDGE TIME Set hello time
setmaxage BRIDGE TIME Set max message age
setpathcost BRIDGE COST Set path cost
setportprio BRIDGE PRIO Set port priority
setbridgeprio BRIDGE PRIO Set bridge priority
stp BRIDGE [1/yes/on|0/no/off] STP on/off
cat [FILE]...
Concatenate FILEs and print them to stdout
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
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
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)
devmem ADDRESS [WIDTH [VALUE]]
Read/write from physical address
ADDRESS Address to act upon
WIDTH Width (8/16/...)
VALUE Data to be written
df [-Pk] [FILESYSTEM]...
Print filesystem usage statistics
-P POSIX output format
-k 1024-byte blocks (default)
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
echo [ARG]...
Print the specified ARGs to stdout
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)
free [-b/k/m/g]
Display the amount of free and used system memory
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 modem's CONNECT status message
-n Don't prompt for login name
-w Wait for CR or LF before sending /etc/issue
-i Don't 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 [-HhnlLoqvsriwF] [-m 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)
-m N Match up to N times per file
-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).
ifconfig [-a] interface [address]
Configure a network interface
[[-]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] ...
init
Init is the parent of all processes
insmod FILE [SYMBOL=VALUE]...
Load the specified kernel modules into the kernel
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
klogd [-c N] [-n]
Kernel logger
-c N Print to console messages more urgent than prio N (1-8)
-n Run in foreground
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
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 [-p] [-h HOST] [[-f] USER]
Begin a new session on the system
-f Don't authenticate (user already authenticated)
-h Name of the remote host
-p Preserve environment
logread [-f]
Show messages in syslogd's circular buffer
-f Output data as log grows
ls [-1AaCxdLHRFplinserSXvctu] [-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
-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
List the currently loaded kernel modules
lsof
Show all open files
md5sum [FILE]...
Print MD5 checksums
mkdir [OPTIONS] DIRECTORY...
Create DIRECTORY
-m MODE Mode
-p No error if exists; make parent directories as needed
mount [OPTIONS] [-o OPTS] DEVICE NODE
Mount a filesystem. Filesystem autodetection requires /proc.
-a Mount all filesystems in fstab
-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
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 Don't resolve names
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)
-t TTL Set TTL
-I IFACE/IP Use interface or IP address as source
-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 displays output at start
and when finished
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 [-o COL1,COL2=HEADER]
Show list of processes
-o COL1,COL2=HEADER Select columns for display
reboot [-d DELAY] [-n] [-f]
Reboot the system
-d SEC Delay interval
-n Do not sync
-f Force (don't go through init)
rm [-irf] FILE...
Remove (unlink) FILEs
-i Always prompt before removing
-f Never prompt
-R,-r Recurse
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 [{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).
sh [-/+OPTIONS] [-/+o OPT]... [-c 'SCRIPT' [ARG0 [ARGS]] / FILE [ARGS]]
Unix shell interpreter
sleep N
Pause for N seconds
sync
Write all buffered blocks to disk
sysctl [OPTIONS] [VALUE]...
Configure kernel parameters at runtime
-n Don't print key names
-e Don't warn about unknown keys
-w Change sysctl setting
-p FILE Load sysctl settings from FILE (default /etc/sysctl.conf)
-a Display all values
-A Display all values in table form
syslogd [OPTIONS]
System logging utility (this version of syslogd ignores /etc/syslog.conf)
-n Run in foreground
-O FILE Log to FILE (default:/var/log/messages)
-l N Log only messages more urgent than prio N (1-8)
-S Smaller output
-R HOST[:PORT] Log to IP or hostname on PORT (default PORT=514/UDP)
-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)
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
-s SECONDS Wait SECONDS between reads with -f
-n N[kbm] Print last N lines
-c N[kbm] Print last N bytes
-q Never print headers
-v Always print headers
N may be suffixed by k (x1024), b (x512), or m (x1024^2). If N starts with a '+', output begins with the Nth item from the start of each file, not from the end.
tar -[cxthvO] [-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
O Extract to stdout
h Follow symlinks
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
-w SEC Inetd 'wait' mode, linger time SEC
-S Log to syslog (implied by -i or without -F and -w)
test EXPRESSION ]
Check file types, compare values etc. Return a 0/1 exit code depending on logical value of EXPRESSION
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
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
Q,^C: exit
Options:
-b Batch mode
-n N Exit after N iterations
-d N Delay between updates
touch [-c] [-d DATE] [-t DATE] [-r FILE] FILE...
Update the last-modified date on the given FILE[s]
-c Don't create files
-d DT Date/time to use
-t DT Date/time to use
-r FILE Use FILE's date/time
true
Return an exit code of TRUE (0)
| udhcpc [-fbnqoCRB] [-i IFACE] [-r IP] [-s PROG] [-p PIDFILE] | |
| [-V VENDOR] [-x OPT:VAL]... [-O OPT]... [-P N] |
-i,--interface IFACE Interface to use (default eth0)
-p,--pidfile FILE Create pidfile
-s,--script PROG Run PROG at DHCP events (default /usr/share/udhcpc/default.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
-P,--client-port N Use port N (default 68)
-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
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
uptime
Display the time since the last boot
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
xargs [OPTIONS] [PROG ARGS]
Run PROG on every item given by stdin
-r Don't run command if input is empty
-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
zcat FILE
Decompress to stdout
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)