1 Please see the LICENSE file for details on copying and usage.
3 BusyBox combines tiny versions of many common UNIX utilities into a single
4 small executable. It provides minimalist replacements for most of the utilities
5 you usually find in fileutils, shellutils, findutils, textutils, grep, gzip,
6 tar, etc. BusyBox provides a fairly complete POSIX environment for any small or
7 embedded system. The utilities in BusyBox generally have fewer options than
8 their full featured GNU cousins; however, the options that are included provide
9 the expected functionality and behave very much like their GNU counterparts.
11 BusyBox was originally written to support the Debian Rescue/Install disks, but
12 it also makes an excellent environment for any small or embedded system.
14 BusyBox has been written with size-optimization and limited resources in mind.
15 It is also extremely modular so you can easily include or exclude commands (or
16 features) at compile time. This makes it easy to customize your embedded
17 systems. To create a working system, just add /dev, /etc, and a kernel.
19 As of version 0.20 there is now a version number. : ) Also as of version 0.20,
20 BusyBox is now modularized to easily allow you to build only the components you
21 need, thereby reducing binary size. Run 'make config' or 'make menuconfig'
22 for select the functionality that you wish to enable.
24 After the build is complete, a busybox.links file is generated. This is
25 used by 'make install' to create symlinks to the busybox binary for all
26 compiled in functions. By default, 'make install' will place the symlink
27 forest into `pwd`/_install unless you have defined the PREFIX environment
28 variable (i.e., 'make PREFIX=/tmp/foo install')
30 If you wish to install hardlinks, rather than symlinks, you can use
31 'make install-hardlinks' instead.
35 Supported architectures:
37 Busybox in general will build on any architecture supported by gcc. It has
38 a few specialized features added for __sparc__ and __alpha__. insmod
39 functionality is currently limited to x86, ARM, SH3/4, powerpc, m68k,
44 glibc-2.0.x, glibc-2.1.x, glibc-2.2.x, glibc-2.3.x, uClibc. People
45 are looking at newlib and diet-libc, but consider them unsupported,
46 untested, or worse. Linux-libc5 is no longer supported -- you
47 should probably use uClibc instead if you want a small C library.
51 Full functionality requires Linux 2.2.x or better. A large fraction of the
52 code should run on just about anything. While the current code is fairly
53 Linux specific, it should be fairly easy to port the majority of the code
54 to, say, FreeBSD or Solaris, or MacOsX, or even Windows (if you are into that
61 lash is the very smallest shell (adds just 10k) and it is quite usable as
62 a command prompt, but it is not suitable for any but the most trivial
63 scripting (such as an initrd that calls insmod a few times) since it does
64 not understand Bourne shell grammer. It does handle pipes, redirects, and
65 job control though. Adding in command editing makes it a very nice
66 lightweight command prompt.
68 hush is also quite small (just 18k) and it has very complete Bourne shell
69 grammer. It handles if/then/else/fi just fine, but doesn't handle loops
70 like for/do/done or case/esac and such. It also currently has a problem
71 with job control. Using hush is not yet recommended.
73 msh: The minix shell (adds just 30k) is quite complete and handles things
74 like for/do/done, case/esac and all the things you expect a Bourne shell to
75 do. It is not always pedantically correct about Bourne shell grammer (try
76 running the shell testscript "tests/sh.testcases" on it and compare vs bash)
77 but for most things it works quite well. It also uses only vfork, so it can
78 be used on uClinux systems. This was only recently added, so there is still
79 room to shrink it further...
81 ash: This adds about 60k in the default configuration and is the most
82 complete and most pedantically correct shell included with busybox. This
83 shell was also recently added, and several people (mainly Vladimir and Erik)
84 have been working on it. There are a number of configurable things at the
85 top of ash.c as well, so check those out if you want to tweak things.
91 When you find you need help, you can check out the BusyBox mailing list
92 archives at http://busybox.net/lists/busybox/ or even join
93 the mailing list if you are interested.
99 If you find bugs, please submit a detailed bug report to the busybox mailing
100 list at busybox@busybox.net. A well-written bug report should include a
101 transcript of a shell session that demonstrates the bad behavior and enables
102 anyone else to duplicate the bug on their own machine. The following is such
105 To: busybox@busybox.net
106 From: diligent@testing.linux.org
107 Subject: /bin/date doesn't work
112 When I execute Busybox 'date' it produces unexpected results.
113 With GNU date I get the following output:
116 Wed Mar 21 14:19:41 MST 2001
118 But when I use BusyBox date I get this instead:
123 I am using Debian unstable, kernel version 2.4.19-rmk1 on an Netwinder,
124 and the latest uClibc from CVS. Thanks for the wonderful program!
128 Note the careful description and use of examples showing not only what BusyBox
129 does, but also a counter example showing what an equivalent GNU app does. Bug
130 reports lacking such detail may never be fixed... Thanks for understanding.
136 Source for the latest released version, as well as daily snapshots, can always
138 http://busybox.net/downloads/
144 BusyBox now has its own publicly browsable CVS tree at:
145 http://busybox.net/cgi-bin/cvsweb/busybox/
147 Anonymous CVS access is available. For instructions, check out:
148 http://busybox.net/cvs_anon.html
150 For those that are actively contributing there is even CVS write access:
151 http://busybox.net/cvs_write.html
155 Please feed suggestions, bug reports, insults, and bribes back to:
157 <andersen@codepoet.org>
158 <andersen@codepoet.org>