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Please see the LICENSE file for details on copying and usage.
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 was originally written to support the Debian Rescue/Install disks, but
it also makes an excellent environment for any small or embedded system.

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 kernel.

As of version 0.20 there is now a version number. : ) Also as of version 0.20,
BusyBox is now modularized to easily allow you to build only the components you
need, thereby reducing binary size. Run 'make config' or 'make menuconfig'
for select the functionality that you wish to enable.

After the build is complete, a busybox.links file is generated.  This is
used by 'make install' to create symlinks to the busybox binary for all
compiled in functions.  By default, 'make install' will place the symlink
forest into `pwd`/_install unless you have defined the PREFIX environment
variable (i.e., 'make PREFIX=/tmp/foo install')

If you wish to install hardlinks, rather than symlinks, you can use 
'make install-hardlinks' instead.

Supported architectures:

   Busybox in general will build on any architecture supported by gcc.  It has
   a few specialized features added for __sparc__ and __alpha__.  insmod
   functionality is currently limited to x86, ARM, SH3/4, powerpc, m68k, 
   MIPS, cris, and v850e.

Supported libcs:

   glibc-2.0.x, glibc-2.1.x, glibc-2.2.x, glibc-2.3.x, uClibc.  People
   are looking at newlib and diet-libc, but consider them unsupported,
   untested, or worse.  Linux-libc5 is no longer supported -- you
   should probably use uClibc instead if you want a small C library.

Supported kernels:

   Full functionality requires Linux 2.2.x or better.  A large fraction of the
   code should run on just about anything.  While the current code is fairly
   Linux specific, it should be fairly easy to port the majority of the code
   to, say, FreeBSD or Solaris, or MacOsX, or even Windows (if you are into that
   sortof thing).


Getting help:

When you find you need help, you can check out the BusyBox mailing list
archives at or even join
the mailing list if you are interested.



If you find bugs, please submit a detailed bug report to the busybox mailing
list at  A well-written bug report should include a
transcript of a shell session that demonstrates the bad behavior and enables
anyone else to duplicate the bug on their own machine. The following is such 
an example:

    Subject: /bin/date doesn't work

    Package: busybox
    Version: 1.00

    When I execute Busybox 'date' it produces unexpected results.
    With GNU date I get the following output:

	$ date
	Wed Mar 21 14:19:41 MST 2001

    But when I use BusyBox date I get this instead:

	$ date
	llegal instruction

    I am using Debian unstable, kernel version 2.4.19-rmk1 on an Netwinder, 
    and the latest uClibc from CVS.  Thanks for the wonderful program!


Note the careful description and use of examples showing not only what BusyBox
does, but also a counter example showing what an equivalent GNU app does.  Bug
reports lacking such detail may never be fixed...  Thanks for understanding.



Source for the latest released version, as well as daily snapshots, can always 
be downloaded from



BusyBox now has its own publicly browsable CVS tree at:

Anonymous CVS access is available.  For instructions, check out:

For those that are actively contributing there is even CVS write access:


Please feed suggestions, bug reports, insults, and bribes back to:
	Erik Andersen