mirror of
https://github.com/topjohnwu/ndk-busybox.git
synced 2024-12-05 02:16:49 +00:00
c77a58fb2d
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
205 lines
8.5 KiB
Plaintext
205 lines
8.5 KiB
Plaintext
Please see the LICENSE file for details on copying and usage.
|
|
Please refer to the INSTALL file for instructions on how to build.
|
|
|
|
What is busybox:
|
|
|
|
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 bzip2, coreutils, dhcp, diffutils, e2fsprogs,
|
|
file, findutils, gawk, grep, inetutils, less, modutils, net-tools, procps,
|
|
sed, shadow, sysklogd, sysvinit, tar, util-linux, and vim. The utilities
|
|
in BusyBox often have fewer options than their full-featured cousins;
|
|
however, the options that are included provide the expected functionality
|
|
and behave very much like their larger counterparts.
|
|
|
|
BusyBox has been written with size-optimization and limited resources in
|
|
mind, both to produce small binaries and to reduce run-time memory usage.
|
|
Busybox is also extremely modular so you can easily include or exclude
|
|
commands (or features) at compile time. This makes it easy to customize
|
|
embedded systems; to create a working system, just add /dev, /etc, and a
|
|
Linux kernel. Busybox (usually together with uClibc) has also been used as
|
|
a component of "thin client" desktop systems, live-CD distributions, rescue
|
|
disks, installers, and so on.
|
|
|
|
BusyBox provides a fairly complete POSIX environment for any small system,
|
|
both embedded environments and more full featured systems concerned about
|
|
space. Busybox is slowly working towards implementing the full Single Unix
|
|
Specification V3 (http://www.opengroup.org/onlinepubs/009695399/), but isn't
|
|
there yet (and for size reasons will probably support at most UTF-8 for
|
|
internationalization). We are also interested in passing the Linux Test
|
|
Project (http://ltp.sourceforge.net).
|
|
|
|
----------------
|
|
|
|
Using busybox:
|
|
|
|
BusyBox is extremely configurable. This allows you to include only the
|
|
components and options you need, thereby reducing binary size. Run 'make
|
|
config' or 'make menuconfig' to select the functionality that you wish to
|
|
enable. (See 'make help' for more commands.)
|
|
|
|
The behavior of busybox is determined by the name it's called under: as
|
|
"cp" it behaves like cp, as "sed" it behaves like sed, and so on. Called
|
|
as "busybox" it takes the second argument as the name of the applet to
|
|
run (I.E. "./busybox ls -l /proc").
|
|
|
|
The "standalone shell" mode is an easy way to try out busybox; this is a
|
|
command shell that calls the built-in applets without needing them to be
|
|
installed in the path. (Note that this requires /proc to be mounted, if
|
|
testing from a boot floppy or in a chroot environment.)
|
|
|
|
The build automatically generates a file "busybox.links", which is used by
|
|
'make install' to create symlinks to the BusyBox binary for all compiled in
|
|
commands. This uses the CONFIG_PREFIX environment variable to specify
|
|
where to install, and installs hardlinks or symlinks depending
|
|
on the configuration preferences. (You can also manually run
|
|
the install script at "applets/install.sh").
|
|
|
|
----------------
|
|
|
|
Downloading the current source code:
|
|
|
|
Source for the latest released version, as well as daily snapshots, can always
|
|
be downloaded from
|
|
|
|
http://busybox.net/downloads/
|
|
|
|
You can browse the up to the minute source code and change history online.
|
|
|
|
http://git.busybox.net/busybox/
|
|
|
|
Anonymous GIT access is available. For instructions, check out:
|
|
|
|
http://www.busybox.net/source.html
|
|
|
|
For those that are actively contributing and would like to check files in,
|
|
see:
|
|
|
|
http://busybox.net/developer.html
|
|
|
|
The developers also have a bug and patch tracking system
|
|
(https://bugs.busybox.net) although posting a bug/patch to the mailing list
|
|
is generally a faster way of getting it fixed, and the complete archive of
|
|
what happened is the git changelog.
|
|
|
|
Note: if you want to compile busybox in a busybox environment you must
|
|
select CONFIG_DESKTOP.
|
|
|
|
----------------
|
|
|
|
Getting help:
|
|
|
|
when you find you need help, you can check out the busybox mailing list
|
|
archives at http://busybox.net/lists/busybox/ or even join
|
|
the mailing list if you are interested.
|
|
|
|
----------------
|
|
|
|
Bugs:
|
|
|
|
if you find bugs, please submit a detailed bug report to the busybox mailing
|
|
list at busybox@busybox.net. 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:
|
|
|
|
to: busybox@busybox.net
|
|
from: diligent@testing.linux.org
|
|
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
|
|
fri oct 8 14:19:41 mdt 2004
|
|
|
|
but when i use busybox date i get this instead:
|
|
|
|
$ date
|
|
illegal instruction
|
|
|
|
i am using debian unstable, kernel version 2.4.25-vrs2 on a netwinder,
|
|
and the latest uclibc from cvs.
|
|
|
|
-diligent
|
|
|
|
note the careful description and use of examples showing not only what
|
|
busybox does, but also a counter example showing what an equivalent app
|
|
does (or pointing to the text of a relevant standard). Bug reports lacking
|
|
such detail may never be fixed... Thanks for understanding.
|
|
|
|
----------------
|
|
|
|
Portability:
|
|
|
|
Busybox is developed and tested on Linux 2.4 and 2.6 kernels, compiled
|
|
with gcc (the unit-at-a-time optimizations in version 3.4 and later are
|
|
worth upgrading to get, but older versions should work), and linked against
|
|
uClibc (0.9.27 or greater) or glibc (2.2 or greater). In such an
|
|
environment, the full set of busybox features should work, and if
|
|
anything doesn't we want to know about it so we can fix it.
|
|
|
|
There are many other environments out there, in which busybox may build
|
|
and run just fine. We just don't test them. Since busybox consists of a
|
|
large number of more or less independent applets, portability is a question
|
|
of which features work where. Some busybox applets (such as cat and rm) are
|
|
highly portable and likely to work just about anywhere, while others (such as
|
|
insmod and losetup) require recent Linux kernels with recent C libraries.
|
|
|
|
Earlier versions of Linux and glibc may or may not work, for any given
|
|
configuration. Linux 2.2 or earlier should mostly work (there's still
|
|
some support code in things like mount.c) but this is no longer regularly
|
|
tested, and inherently won't support certain features (such as long files
|
|
and --bind mounts). The same is true for glibc 2.0 and 2.1: expect a higher
|
|
testing and debugging burden using such old infrastructure. (The busybox
|
|
developers are not very interested in supporting these older versions, but
|
|
will probably accept small self-contained patches to fix simple problems.)
|
|
|
|
Some environments are not recommended. Early versions of uClibc were buggy
|
|
and missing many features: upgrade. Linking against libc5 or dietlibc is
|
|
not supported and not interesting to the busybox developers. (The first is
|
|
obsolete and has no known size or feature advantages over uClibc, the second
|
|
has known bugs that its developers have actively refused to fix.) Ancient
|
|
Linux kernels (2.0.x and earlier) are similarly uninteresting.
|
|
|
|
In theory it's possible to use Busybox under other operating systems (such as
|
|
MacOS X, Solaris, Cygwin, or the BSD Fork Du Jour). This generally involves
|
|
a different kernel and a different C library at the same time. While it
|
|
should be possible to port the majority of the code to work in one of
|
|
these environments, don't be surprised if it doesn't work out of the box. If
|
|
you're into that sort of thing, start small (selecting just a few applets)
|
|
and work your way up.
|
|
|
|
In 2005 Shaun Jackman has ported busybox to a combination of newlib
|
|
and libgloss, and some of his patches have been integrated.
|
|
|
|
Supported hardware:
|
|
|
|
BusyBox in general will build on any architecture supported by gcc. We
|
|
support both 32 and 64 bit platforms, and both big and little endian
|
|
systems.
|
|
|
|
Under 2.4 Linux kernels, kernel module loading was implemented in a
|
|
platform-specific manner. Busybox's insmod utility has been reported to
|
|
work under ARM, CRIS, H8/300, x86, ia64, x86_64, m68k, MIPS, PowerPC, S390,
|
|
SH3/4/5, Sparc, and v850e. Anything else probably won't work.
|
|
|
|
The module loading mechanism for the 2.6 kernel is much more generic, and
|
|
we believe 2.6.x kernel module loading support should work on all
|
|
architectures supported by the kernel.
|
|
|
|
----------------
|
|
|
|
Please feed suggestions, bug reports, insults, and bribes back to the busybox
|
|
mailing list:
|
|
|
|
busybox@busybox.net
|
|
|
|
and/or maintainer:
|
|
|
|
Denys Vlasenko
|
|
<vda.linux@googlemail.com>
|