X-Git-Url: https://git.librecmc.org/?a=blobdiff_plain;f=INSTALL;h=750cfc45bfd6de4a96ff73ebcd4e512a395ad96b;hb=505eeae402a84dc5208986c5ad611f5e485cbe34;hp=a137da2375dede145ef98b402f91de7dfc49fa1f;hpb=cb81e6484d1f50ec2761f6294722407b14add525;p=oweals%2Fbusybox.git diff --git a/INSTALL b/INSTALL index a137da237..750cfc45b 100644 --- a/INSTALL +++ b/INSTALL @@ -1,20 +1,142 @@ -1) Run 'make config' or 'make menuconfig' and select the - functionality that you wish to enable. +Building: +========= -2) Run 'make dep' +The BusyBox build process is similar to the Linux kernel build: -3) Check the Makefile for any Makefile setting you wish - to adjust for your system (things like like setting - your cross compiler, adjusting optimizations, etc) + make menuconfig # This creates a file called ".config" + make # This creates the "busybox" executable + make install # or make CONFIG_PREFIX=/path/from/root install -4) Run 'make' +The full list of configuration and install options is available by typing: -5) Go get a drink of water, drink a soda, visit the bathroom, - or whatever while it compiles. It doesn't take very - long to compile, so you don't really need to waste too - much time waiting... + make help -6) Run 'make install' or 'make PREFIX=/target install' to - install busybox and all the needed links. Some people - will prefer to install using hardlinks and will instead - want to run 'make install-hardlinks'.... +Quick Start: +============ + +The easy way to try out BusyBox for the first time, without having to install +it, is to enable all features and then use "standalone shell" mode with a +blank command $PATH. + +To enable all features, use "make defconfig", which produces the largest +general-purpose configuration. It's allyesconfig minus debugging options, +optional packaging choices, and a few special-purpose features requiring +extra configuration to use. Then enable "standalone shell" feature: + + make defconfig + make menuconfig + # select Busybox Settings + # then General Configuration + # then exec prefers applets + # exit back to top level menu + # select Shells + # then Standalone shell + # exit back to top level menu + # exit and save new configuration + # OR + # use these commands to modify .config directly: + sed -e 's/.*FEATURE_PREFER_APPLETS.*/CONFIG_FEATURE_PREFER_APPLETS=y/' -i .config + sed -e 's/.*FEATURE_SH_STANDALONE.*/CONFIG_FEATURE_SH_STANDALONE=y/' -i .config + make + PATH= ./busybox ash + +Standalone shell mode causes busybox's built-in command shell to run +any built-in busybox applets directly, without looking for external +programs by that name. Supplying an empty command path (as above) means +the only commands busybox can find are the built-in ones. + +Note that the standalone shell requires CONFIG_BUSYBOX_EXEC_PATH +to be set appropriately, depending on whether or not /proc/self/exe is +available. If you do not have /proc, then point that config option +to the location of your busybox binary, usually /bin/busybox. +Another solution is to patch the kernel (see +examples/linux-*_proc_self_exe.patch) to make exec("/proc/self/exe") +always work. + +Configuring Busybox: +==================== + +Busybox is optimized for size, but enabling the full set of functionality +still results in a fairly large executable -- more than 1 megabyte when +statically linked. To save space, busybox can be configured with only the +set of applets needed for each environment. The minimal configuration, with +all applets disabled, produces a 4k executable. (It's useless, but very small.) + +The manual configurator "make menuconfig" modifies the existing configuration. +(For systems without ncurses, try "make config" instead.) The two most +interesting starting configurations are "make allnoconfig" (to start with +everything disabled and add just what you need), and "make defconfig" (to +start with everything enabled and remove what you don't need). If menuconfig +is run without an existing configuration, make defconfig will run first to +create a known starting point. + +Other starting configurations (mostly used for testing purposes) include +"make allbareconfig" (enables all applets but disables all optional features), +"make allyesconfig" (enables absolutely everything including debug features), +and "make randconfig" (produce a random configuration). The configs/ directory +contains a number of additional configuration files ending in _defconfig which +are useful in specific cases. "make help" will list them. + +Configuring BusyBox produces a file ".config", which can be saved for future +use. Run "make oldconfig" to bring a .config file from an older version of +busybox up to date. + +Installing Busybox: +=================== + +Busybox is a single executable that can behave like many different commands, +and BusyBox uses the name it was invoked under to determine the desired +behavior. (Try "mv busybox ls" and then "./ls -l".) + +Installing busybox consists of creating symlinks (or hardlinks) to the busybox +binary for each applet enabled in busybox, and making sure these symlinks are +in the shell's command $PATH. Running "make install" creates these symlinks, +or "make install-hardlinks" creates hardlinks instead (useful on systems with +a limited number of inodes). This install process uses the file +"busybox.links" (created by make), which contains the list of enabled applets +and the path at which to install them. + +Installing links to busybox is not always necessary. The special applet name +"busybox" (or with any optional suffix, such as "busybox-static") uses the +first argument to determine which applet to behave as, for example +"./busybox cat LICENSE". (Running the busybox applet with no arguments gives +a list of all enabled applets.) The standalone shell can also call busybox +applets without links to busybox under other names in the filesystem. You can +also configure a standalone install capability into the busybox base applet, +and then install such links at runtime with one of "busybox --install" (for +hardlinks) or "busybox --install -s" (for symlinks). + +If you enabled the busybox shared library feature (libbusybox.so) and want +to run tests without installing, set your LD_LIBRARY_PATH accordingly when +running the executable: + + LD_LIBRARY_PATH=`pwd` ./busybox + +Building out-of-tree: +===================== + +By default, the BusyBox build puts its temporary files in the source tree. +Building from a read-only source tree, or building multiple configurations from +the same source directory, requires the ability to put the temporary files +somewhere else. + +To build out of tree, cd to an empty directory and configure busybox from there: + + make KBUILD_SRC=/path/to/source -f /path/to/source/Makefile defconfig + make + make install + +Alternately, use the O=$BUILDPATH option (with an absolute path) during the +configuration step, as in: + + make O=/some/empty/directory allyesconfig + cd /some/empty/directory + make + make CONFIG_PREFIX=. install + +More Information: +================= + +Se also the busybox FAQ, under the questions "How can I get started using +BusyBox" and "How do I build a BusyBox-based system?" The BusyBox FAQ is +available from http://www.busybox.net/FAQ.html