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diff --git a/docs/FAQ.txt b/docs/FAQ.txt deleted file mode 100644 index 87322174c..000000000 --- a/docs/FAQ.txt +++ /dev/null @@ -1,186 +0,0 @@ -This is a collection of some of the frequently asked question -about uClibc. Some of the questions even have answers. If you -have additions to this FAQ document, I'd love to add them, - - -Erik - - -Q: What platforms does uClibc run on? - - Currently uClibc runs on arm, i386, m68k, mipsel, powerpc, sh, - sparc, and v850. - - - -Q: Does uClibc support shared libraries? - - Yes. uClibc has shared library support on x86, arm, and powerpc. - Shared Libraries are _not_ currently supported on MMU-less systems. - - - -Q: Why is it called uClibc? - - The letter 'u' is short for the greek letter "mu". "Mu" stands for - "micro", and the "C" is for "controller". uClibc was originaly created to - support uClinux, a port of Linux for MMU-less microcontrollers such as the - Dragonball, Coldfire, and ARM7TDMI. - - - -Q: Can I use it on my desktop x86 system? - - Sure! In fact, this can be very nice during development. By using it on - your development system, you can be sure that the code you are working on - will actually run on your target system. - - - -Q: Why are you doing this? Whats wrong with glibc? - - The inital reason, is that glibc does not support MMU-les systems. But - additionaly, the GNU C library has a different set of goals then uClibc. - The GNU C library is a great piece of software. It complies with just - about every standard ever created, and runs on just about every operating - system as well -- no small task! But there is a price to be paid for that. - It is quite a large library, and keeps getting larger with each release. - It does not even pretend to target embedded systems. To quote from Ulrich - Drepper, the maintainer of GNU libc: "...glibc is not the right thing for - [an embedded OS]. It is designed as a native library (as opposed to - embedded). Many functions (e.g., printf) contain functionality which is - not wanted in embedded systems." 24 May 1999 - - - -Q: So uClibc is smaller then glibc? Doesn't that mean it completely sucks? - How could it be smaller and not suck? - - uClibc has been designed from the ground up to be a C library for embedded - Linux. We don't need to worry about whether we support MS-DOS, or Cygwin, - or any other system. This lets us cut out lots of complexity, and very - carefully optimize for Linux. By very careful design, we can also make a - few shotcuts. For example, glibc contains an implementation of the - wordexp() function, in compliance with the Single Unix Specificaion, - version 2. Well, standards are important. But so is pragmatism. The - wordexp function adds almost 100k to glibc, and yet I am not aware of even - one Linux application that uses wordexp. So uClibc doesn't have wordexp(). - - Glibc is a general purpose C library, and so as policy things are optimized - for speed. uClibc has a large number of routines that have been very - carefuly written to optimize for size instead of speed. - - The end result is a C library that will compile just about everything you - throw at it, thet looks like glibc to application programs when you - compile, and is many times smaller. - - - -Q: Why should I use uClibc? - - I don't know if you should use uClibc or not. It depends on your goals. - If you are building an embedded system, and you are tight on space, then - using uClibc instead if glibc should allow you to use your storage for - other things. - - If you are trying to build a ultra fast fileserver for your company that - has 12 Terabytes of storage, then you probably want to use glibc... - - - -Q: I want to create a closed source commercial application and I want to - protect my intellectual property. If I use uClibc, don't I have to - release my source code? - - No, you do not need to give away your source code just because you use - uClibc and/or run on Linux. - - - -Q: I want to create a closed source commercial application using uClibc. - Is that legal? - - Yes. uClibc is licensed under the LGPL, just like GNU libc. If you are - using uClibc as a shared library, then your closed source application is - 100% legal. Please consider sharing some of the money you make. :-) - - If you are staticly linking your closed source commercial application with - uClibc, then you must take additional steps to comply with the uClibc - license. You can sell your application as usual, but you must also make - your closed source application available to your customers as an object - file which can then be linked with updated versions of uClibc. This will - (in theory) allow your customers to later link with updated versions of - uClibc. You do not need to make the application object file available to - everyone, just to those you gave the fully linked application. - - - -Q: How do I compile stuff? - - The easiest way is to use the compiler wrapper built by uClibc. Instead of - using your usual compiler or cross compiler, you can use i386-uclibc-gcc, - (or whatever is appropriate for your architecture) and it will automagically - make your program link against uClibc. - - - -Q: How do I make autoconf and automake behave? - - First run - export PATH=/usr/i386-linux-uclibc/bin:$PATH - (or similar adjusted for your target architecture) then run you can simply - run autoconf/automake and it should _just work_. - - - -Q: When I run 'ldd' to get a list of the library dependancies for a uClibc - binary, ldd segfault! Or it runs my application? Anyways, it doesn't - work! What should I do? - - Use the ldd that is built by uClibc, not your system's one. When your - system's ldd looks for the library dependancies, it actually tries to - _execute_ that program. This works fine -- usually. I doesn't work at all - when you are cross compiling (thats why ldd segfaults). The ldd program - created by uClibc is cross platform and doesn't actually try to run the - target program like your system one does, so it should do the right thing, - and won't segfault, even when you are cross compiling. - - - -Q: I need you to add <favorite feature> now! How come you don't answer all my - questions on the mailing list withing 5 minutes? I demand that you help me - Right Now! - - You have not paid me a single cent and yet you still have the product of - over year and a half of my work, and lots of work from other people. How - dare you treat me that way! I work on uClibc because I find it - interesting. If you go off flaming me, I will ignore you. - - - -Q: I need you to add <favorite feature>! Are the uClibc developers willing to - be paid in order to add in <favorite feature>? Are you willing to provide - support contracts? - - 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 several other - active contributors who may be able to help you out. - - -Q: I think you guys are great and I want to help support your work! - - Wow, that would be great! You can visit - http://paypal.com/ - click on "Send Money" and donate to andersen@codepoet.org - - - -I hope that was helpful... If you have and comment, corrections, insults, -suggestions, or bribes, email me at andersen@codepoet.org. - - -Erik - --- -Erik B. Andersen -andersen@codepoet.org -http://codepoet-consulting.com/ |