Full functionality requires Linux 2.2.x or better. A large fraction of the code should run on just about anything. While the current code is fairly Linux specific, it should be fairly easy to port the majority of the code to support, say, FreeBSD or Solaris, or Mac OS X, or even Windows (if you are into that sort of thing).
BusyBox in general will build on any architecture supported by gcc. Kernel module loading for 2.2 and 2.4 Linux kernels is currently limited to ARM, CRIS, H8/300, x86, ia64, x86_64, m68k, MIPS, PowerPC, S390, SH3/4/5, Sparc, v850e, and x86_64 for 2.4.x kernels. With 2.6.x kernels, module loading support should work on all architectures.
uClibc and glibc are supported. People have been looking at newlib and dietlibc, but they are currently considered unsupported, untested, or worse. Linux-libc5 is no longer supported. If you require a small C library, you should probably use uClibc.
If you simply need help with using or configuring BusyBox, please submit a detailed description of your problem to the BusyBox mailing list at busybox@mail.busybox.net. Please do not send private email to Erik (the maintainer of BusyBox) asking for private help unless you are planning on paying for consulting services. When we answer questions on the BusyBox mailing list, it helps everyone, while private answers help only you...
The developers of BusyBox are busy people, and have only so much they can keep in their brains at a time. As a result, bug reports sometimes get lost when posted to the mailing list. To prevent your bug report from getting lost, if you find a bug in BusyBox, please use the BusyBox Bug and Patch Tracking System to submit a detailed bug report.
The same also applies to patches... Regardless of whether your patch is a bug fix or adds shiney new features, please post your patch to the BusyBox Bug and Patch Tracking System to make certain it is properly considered.
Job control will be turned off since your shell can not obtain a controlling terminal. This typically happens when you run your shell on /dev/console. The kernel will not provide a controlling terminal on the /dev/console device. Your should run your shell on a normal tty such as tty1 or ttyS0 and everything will work perfectly. If you REALLY want your shell to run on /dev/console, then you can hack your kernel (if you are into that sortof thing) by changing drivers/char/tty_io.c to change the lines where it sets "noctty = 1;" to instead set it to "0". I recommend you instead run your shell on a real console...
An easy method to build your own basic BusyBox based system, is to follow these simple steps:
You have not paid us a single cent and yet you still have the product of many years of our work. We are not your slaves! We work on BusyBox because we find it useful and interesting. If you go off flaming us, we will ignore you.
If you find that you need help with BusyBox, you can ask for help on the BusyBox mailing list at busybox@mail.busybox.net. In addition to the BusyBox mailing list, Erik (andersee), Manuel (mjn3) and others are known to hang out on the uClibc IRC channel: #uclibc on irc.freenode.net.
Please do not send private email to Erik, Manuel, or the other BusyBox contributors asking for private help unless you are planning on paying for consulting services.
When we answer questions on the BusyBox mailing list, it helps everyone since people with similar problems in the future will be able to get help by searching the mailing list archives. Private help is reserved as a paid service. If you need to use private communication, or if you are serious about getting timely assistance with BusyBox, you should seriously consider paying for consulting services.
Sure! Now you have our attention! What you should do is contact Erik Andersen of CodePoet Consulting to bid on your project. If Erik is too busy to personally add your feature, there are many other active BusyBox contributors who will almost certainly be able to help you out. Erik can contact them privately, and may even let you to post your request for services on the mailing list.
We maintain such a list on this site!
Wow, that would be great! If you would like to make a donation to help support BusyBox, and/or request features, you can click here:
To conserve bytes it's good to know where they're being used, and the size of the final executable isn't always a reliable indicator of the size of the components (since various structures are rounded up, so a small change may not even be visible by itself, but many small savings add up).
To examine a busybox binary with an eye to saving bytes, build an optimized debug version and run the "nm" command against it, like so:
make clean && make STRIPCMD=/bin/true && nm --size-sort busybox
This gives a list of symbols and the amount of space allocated for each one, sorted by size. (Note: do not enable CONFIG_DEBUG for this, as that disables compiler optimization which is great for running gdb but misleading when trying to figure out how much space each component is really using under normal circumstances.)