Please see the LICENSE file for copyright information.
+
+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 is a suite of "tiny" Unix utilities in a multi-call binary. It
-provides a pretty complete POSIX environment in a very small package.
-Just add a kernel, "ash" (Keith Almquists tiny Bourne shell clone), and
-an editor such as "elvis-tiny" or "ae", and you have a working system.
-Busybox was begun to support the Debian Rescue/Install disks, but it
-also makes an excellent environment for any small or embedded system.
-
-As of version 0.20 there is a version number. : ) Also as of version 0.20, BB
-is now modularized to easily allow you to build only the BB parts you need,
-thereby reducing binary size. To turn off unwanted Busybox components, simply
-edit the file busybox.def.h and comment out the parts you do not need using C++
-style (//) comments.
-
-After the build is complete a busybox.links file is generated which is
-then 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)
+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, a shell, and a kernel. For
+a really minimal system, you can even use the busybox shell (not Bourne
+compatible, but very small and quite usable) and the busybox vi editor.
+
+BusyBox was originally written to support the Debian Rescue/Install disks, but
+it also makes an excellent environment for any small or embedded system.
+
+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. To turn off unwanted BusyBox components,
+simply edit the file "Config.h" and comment out the components you do not need
+using C++ style (//) comments.
+
+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')
+
+----------------
+
+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,
+ and MIPS.
+
+Supported libcs:
+
+ glibc-2.0.x, glibc-2.1.x, Linux-libc5, uClibc. People are looking at
+ newlib and diet-libc, but consider them unsupported, untested, or worse.
+
+Supported kernels:
+
+ Full functionality requires Linux 2.0.x, 2.2.x, or 2.4.x. A large fraction
+ of the code should run on just about anything.
+
+----------------
+
+Shells:
+
+lash is the very smallest shell (adds just 10k) and it is quite usable as
+a command prompt, but it is not suitable for any but the most trivial
+scripting (such as an initrd that calls insmod a few times) since it does
+not understand Bourne shell grammer. It does handle pipes, redirects, and
+job control though. Adding in command editing makes it very nice
+lightweight command prompt.
+
+hush is also quite small (just 18k) and it has very complete Bourne shell
+grammer. It handles if/then/else/fi just fine, but doesn't handle loops
+like for/do/done or case/esac and such. It also currently has a problem
+with job control.
+
+msh: The minix shell (adds just 30k) is quite complete and handles things
+like for/do/done, case/esac and all the things you expect a Bourne shell to
+do. It is not always pedantically correct about Bourne shell grammer (try
+running the shell testscript "tests/sh.testcases" on it and compare vs bash)
+but for most things it works quite well. It also uses only vfork, so it can
+be used on uClinux systems. This was only recently added, so there is still
+room to shrink it further...
+
+ash: This adds about 60k in the default configuration and is the most
+complete and most pedantically correct shell included with busybox. This
+shell was also recently added, and several people (mainly Vladimir and Erik)
+have been working on it. There are a number of configurable things at the
+top of ash.c as well, so check those out if you want to tweak things. The
+Posix math support is currently disabled (that bit of code was horrible) but
+will be restored for the next BusyBox release.
+
+----------------
+
+Getting help:
+
+When you find you need help, you can check out the BusyBox mailing list
+archives at http://opensource.lineo.com/lists/busybox/ or even join
+the mailing list if you are interested.
+
+----------------
+
+Bugs:
+
+If you find bugs, please submit a bug report. Full instructions on how to
+report a bug are found at http://bugs.lineo.com/Reporting.html.
+
+For the impatient: To submit a bug, simply send an email describing the problem
+to submit@bugs.lineo.com. Bug reports should look something like this:
+
+ To: submit@bugs.lineo.com
+ From: diligent@testing.linux.org
+ Subject: /bin/true doesn't work
+
+ Package: busybox
+ Version: 0.51
+
+ When I invoke '/bin/true' it doesn't work. I expected it to return
+ a "0" but it returned a "1" instead. Here is the transcript:
+ $ /bin/true ; echo $?
+ 1
+ With GNU /bin/true, I get the following output:
+ $ /bin/true ; echo $?
+ 0
+ I am using Debian 2.2r2, kernel version 2.2.18, and the latest
+ uClibc from CVS. Thanks for the wonderful program!
+ -Diligent
+
+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 take a _long_ time to be fixed... Thanks for
+understanding.
+
+----------------
+
+FTP:
+
+Source for the latest released version can always be downloaded from
+ ftp://ftp.lineo.com/pub/busybox.
+
+----------------
+
+CVS:
+
+BusyBox now has its own publicly browsable CVS tree at:
+ http://opensource.lineo.com/cgi-bin/cvsweb/busybox/
+
+Anonymous CVS access is available. For instructions, check out:
+ http://opensource.lineo.com/cvs_anon.html
+
+For those that are actively contributing there is even CVS write access:
+ http://opensource.lineo.com/cvs_write.html
+
+----------------
Please feed suggestions, bug reports, insults, and bribes back to:
Erik Andersen
<andersen@lineo.com>
<andersee@debian.org>
+ <andersee@codepoet.org>
-<blatent plug>
+<blatant plug>
Many thanks to go to Lineo for paying me to work on busybox.
-</blatent plug>
+</blatant plug>
projects / oweals / busybox.git / blobdiff