1# vi: set sw=4 ts=4: 2 3=head1 NAME 4 5BusyBox - The Swiss Army Knife of Embedded Linux 6 7=head1 SYNTAX 8 9 busybox <applet> [arguments...] # or 10 11 <applet> [arguments...] # if symlinked 12 13=head1 DESCRIPTION 14 15BusyBox combines tiny versions of many common UNIX utilities into a single 16small executable. It provides minimalist replacements for most of the utilities 17you usually find in GNU coreutils, util-linux, etc. The utilities in BusyBox 18generally have fewer options than their full-featured GNU cousins; however, the 19options that are included provide the expected functionality and behave very 20much like their GNU counterparts. 21 22BusyBox has been written with size-optimization and limited resources in mind. 23It is also extremely modular so you can easily include or exclude commands (or 24features) at compile time. This makes it easy to customize your embedded 25systems. To create a working system, just add /dev, /etc, and a Linux kernel. 26BusyBox provides a fairly complete POSIX environment for any small or embedded 27system. 28 29BusyBox is extremely configurable. This allows you to include only the 30components you need, thereby reducing binary size. Run 'make config' or 'make 31menuconfig' to select the functionality that you wish to enable. Then run 32'make' to compile BusyBox using your configuration. 33 34After the compile has finished, you should use 'make install' to install 35BusyBox. This will install the 'bin/busybox' binary, in the target directory 36specified by CONFIG_PREFIX. CONFIG_PREFIX can be set when configuring BusyBox, 37or you can specify an alternative location at install time (i.e., with a 38command line like 'make CONFIG_PREFIX=/tmp/foo install'). If you enabled 39any applet installation scheme (either as symlinks or hardlinks), these will 40also be installed in the location pointed to by CONFIG_PREFIX. 41 42=head1 USAGE 43 44BusyBox is a multi-call binary. A multi-call binary is an executable program 45that performs the same job as more than one utility program. That means there 46is just a single BusyBox binary, but that single binary acts like a large 47number of utilities. This allows BusyBox to be smaller since all the built-in 48utility programs (we call them applets) can share code for many common 49operations. 50 51You can also invoke BusyBox by issuing a command as an argument on the 52command line. For example, entering 53 54 /bin/busybox ls 55 56will also cause BusyBox to behave as 'ls'. 57 58Of course, adding '/bin/busybox' into every command would be painful. So most 59people will invoke BusyBox using links to the BusyBox binary. 60 61For example, entering 62 63 ln -s /bin/busybox ls 64 ./ls 65 66will cause BusyBox to behave as 'ls' (if the 'ls' command has been compiled 67into BusyBox). Generally speaking, you should never need to make all these 68links yourself, as the BusyBox build system will do this for you when you run 69the 'make install' command. 70 71If you invoke BusyBox with no arguments, it will provide you with a list of the 72applets that have been compiled into your BusyBox binary. 73 74=head1 COMMON OPTIONS 75 76Most BusyBox applets support the B<--help> argument to provide a terse runtime 77description of their behavior. If the CONFIG_FEATURE_VERBOSE_USAGE option has 78been enabled, more detailed usage information will also be available. 79 80=head1 COMMANDS 81 82Currently available applets include: 83