1 Please see the LICENSE file for details on copying and usage.
2 Please refer to the INSTALL file for instructions on how to build.
6 BusyBox combines tiny versions of many common UNIX utilities into a single
7 small executable. It provides minimalist replacements for most of the
8 utilities you usually find in bzip2, coreutils, e2fsprogs, file, findutils,
9 gawk, grep, inetutils, less, modutils, net-tools, procps, sed, shadow,
10 sysklogd, sysvinit, tar, util-linux, and vim. The utilities in BusyBox
11 often have fewer options than their full-featured cousins; however, the
12 options that are included provide the expected functionality and behave
13 very much like their larger counterparts.
15 BusyBox has been written with size-optimization and limited resources in
16 mind, both to produce small binaries and to reduce run-time memory usage.
17 Busybox is also extremely modular so you can easily include or exclude
18 commands (or features) at compile time. This makes it easy to customize
19 embedded systems; to create a working system, just add /dev, /etc, and a
20 Linux kernel. Busybox (usually together with uClibc) has also been used as
21 a component of "thin client" desktop systems, live-CD distributions, rescue
22 disks, installers, and so on.
24 BusyBox provides a fairly complete POSIX environment for any small system,
25 both embedded environments and more full featured systems concerned about
26 space. Busybox is slowly working towards implementing the full Single Unix
27 Specification V3 (http://www.opengroup.org/onlinepubs/009695399/), but isn't
28 there yet (and for size reasons will probably support at most UTF-8 for
29 internationalization). We are also interested in passing the Linux Test
30 Project (http://ltp.sourceforge.net).
36 BusyBox is extremely configurable. This allows you to include only the
37 components and options you need, thereby reducing binary size. Run 'make
38 config' or 'make menuconfig' to select the functionality that you wish to
39 enable. (See 'make help' for more commands.)
41 The behavior of busybox is determined by the name it's called under: as
42 "cp" it behaves like cp, as "sed" it behaves like sed, and so on. Called
43 as "busybox" it takes the second argument as the name of the applet to
44 run (I.E. "./busybox ls -l /proc").
46 The "standalone shell" mode is an easy way to try out busybox; this is a
47 command shell that calls the builtin applets without needing them to be
48 installed in the path. (Note that this requires /proc to be mounted, if
49 testing from a boot floppy or in a chroot environment.)
51 The build automatically generates a file "busybox.links", which is used by
52 'make install' to create symlinks to the BusyBox binary for all compiled in
53 commands. This uses the PREFIX environment variable to specify where to
54 install, and installs hardlinks or symlinks depending on the configuration
55 preferences. (You can also manually run the install script at
56 "applets/install.sh").
60 Downloading the current source code:
62 Source for the latest released version, as well as daily snapshots, can always
65 http://busybox.net/downloads/
67 You can browse the up to the minute source code and change history online.
68 The "stable" series is at:
70 http://www.busybox.net/cgi-bin/viewcvs.cgi/branches/busybox_1_00_stable/busybox/
72 And the development series is at:
74 http://www.busybox.net/cgi-bin/viewcvs.cgi/trunk/busybox/
76 Anonymous SVN access is available. For instructions, check out:
78 http://busybox.net/subversion.html
80 For those that are actively contributing and would like to check files in,
83 http://busybox.net/developer.html
85 The developers also have a bug and patch tracking system
86 (http://bugs.busybox.net) although posting a bug/patch to the mailing list
87 is generally a faster way of getting it fixed, and the complete archive of
88 what happened is the subversion changelog.
94 when you find you need help, you can check out the busybox mailing list
95 archives at http://busybox.net/lists/busybox/ or even join
96 the mailing list if you are interested.
102 if you find bugs, please submit a detailed bug report to the busybox mailing
103 list at busybox@busybox.net. a well-written bug report should include a
104 transcript of a shell session that demonstrates the bad behavior and enables
105 anyone else to duplicate the bug on their own machine. the following is such
108 to: busybox@busybox.net
109 from: diligent@testing.linux.org
110 subject: /bin/date doesn't work
115 when i execute busybox 'date' it produces unexpected results.
116 with gnu date i get the following output:
119 fri oct 8 14:19:41 mdt 2004
121 but when i use busybox date i get this instead:
126 i am using debian unstable, kernel version 2.4.25-vrs2 on a netwinder,
127 and the latest uclibc from cvs. thanks for the wonderful program!
131 note the careful description and use of examples showing not only what
132 busybox does, but also a counter example showing what an equivalent app
133 does (or pointing to the text of a relevant standard). Bug reports lacking
134 such detail may never be fixed... Thanks for understanding.
140 Busybox is developed and tested on Linux 2.4 and 2.6 kernels, compiled
141 with gcc (the unit-at-a-time optimizations in version 3.4 and later are
142 worth upgrading to get, but older versions should work), and linked against
143 uClibc (0.9.27 or greater) or glibc (2.2 or greater). In such an
144 environment, the full set of busybox features should work, and if
145 anything doesn't we want to know about it so we can fix it.
147 There are many other environments out there, in which busybox may build
148 and run just fine. We just don't test them. Since busybox consists of a
149 large number of more or less independent applets, portability is a question
150 of which features work where. Some busybox applets (such as cat and rm) are
151 highly portable and likely to work just about anywhere, while others (such as
152 insmod and losetup) require recent Linux kernels with recent C libraries.
154 Earlier versions of Linux and glibc may or may not work, for any given
155 configuration. Linux 2.2 or earlier should mostly work (there's still
156 some support code in things like mount.c) but this is no longer regularly
157 tested, and inherently won't support certain features (such as long files
158 and --bind mounts). The same is true for glibc 2.0 and 2.1: expect a higher
159 testing and debugging burden using such old infrastructure. (The busybox
160 developers are not very interested in supporting these older versions, but
161 will probably accept small self-contained patches to fix simple problems.)
163 Some environments are not recommended. Early versions of uClibc were buggy
164 and missing many features: upgrade. Linking against libc5 or dietlibc is
165 not supported and not interesting to the busybox developers. (The first is
166 obsolete and has no known size or feature advantages over uClibc, the second
167 has known bugs that its developers have actively refused to fix.) Ancient
168 Linux kernels (2.0.x and earlier) are similarly uninteresting.
170 In theory it's possible to use Busybox under other operating systems (such as
171 MacOS X, Solaris, Cygwin, or the BSD Fork Du Jour). This generally involves
172 a different kernel and a different C library at the same time. While it
173 should be possible to port the majority of the code to work in one of
174 these environments, don't be suprised if it doesn't work out of the box. If
175 you're into that sort of thing, start small (selecting just a few applets)
176 and work your way up.
178 Shaun Jackman has recently (2005) ported busybox to a combination of newlib
179 and libgloss, and some of his patches have been integrated. This platform
180 may join glibc/uclibc and Linux as a supported combination with the 1.1
181 release, but is not supported in 1.0.
185 BusyBox in general will build on any architecture supported by gcc. We
186 support both 32 and 64 bit platforms, and both big and little endian
189 Under 2.4 Linux kernels, kernel module loading was implemented in a
190 platform-specific manner. Busybox's insmod utility has been reported to
191 work under ARM, CRIS, H8/300, x86, ia64, x86_64, m68k, MIPS, PowerPC, S390,
192 SH3/4/5, Sparc, v850e, and x86_64. Anything else probably won't work.
194 The module loading mechanism for the 2.6 kernel is much more generic, and
195 we believe 2.6.x kernel module loading support should work on all
196 architectures supported by the kernel.
200 Please feed suggestions, bug reports, insults, and bribes back to the busybox
203 <andersen@codepoet.org>