--- /dev/null
+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: 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
+
+
+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/
OSDN Git Service
