[LUAU] libs

[Seth Rightmer]

"David C. Eason, Jr." wrote:

> Ok here goes :).  People keep saying make sure your libs are updated and etc
> etc. What libs, and where do I get updates.  Also, how do I find out what
> version my current libs are?
>
> Dave Eason

"libs" are shared libraries, kinda like DLLs in the windows world, and just as
prone to flukey problems of misconfiguration and incompatible versions.  The
"biggy" is libc, or glibc as it is now called.  This is the main library for
programs written in the C programming language.  Confusingly,  the previous
major version was libc5, but libc6 is now known as glibc2.  Go figure.  This
brings up another interesting point, major and minor version numbers.  Major is
before the dot, minor, after.  Theoretically,  minor verion number updates mean
bug fixes and minor changes that don't require programs linked against the
libraries to be recompiled.  Major version number changes indicate new
features, removal of old features, changes in the API, and a big trip down gcc
lane.  However, the theory breaks down when you are talking about libraries
that are in heavy deveelopment, often indicated, like the kernel by an odd
minor revision number.

Other important libraries are the X windows libraries, the graphic file format
libraries, the ncurses terminal manipulation libraries, various advanced math
libraries, and database libraries.  There are others too numerous to mention.

The safest way to get updates is through your distribution's ftp site.  That
way, you are using their packaging system, which (hopefully) knows all about
the various program and inter-library dependancies, and can tell you when you
need to update other files after a library update.  The libraries are all
maintained by different folks, at different sites.  One good resource for
finding out about library updates is http://www.freshmeat.org/  and another is
ftp://sunsite.unc.edu.  Be warned, if you update libraries by downloading and
compiling the sources, you can break your system bigtime.  Know what you are
doing, and why you need a particular library before doing this, or put the new
libraries in a seperate directory.  You can then include the new directory in
the bottom of your /etc/ld.so.conf file and run ldconfig as root.  You will
then have to indicate to programs you wish to compile against the libraries
where to find them and their associated header files.

There is, needles to say, a lot more to libraries than this, but this should
get you started.  If somebody says, "make sure your libraries are up to date
before you compile/install my new program x," find out what libraries and
versions they mean, specifically.  If you hear people saying "make sure your
libraries are up to date" in a general sense, ignore them or make them be more
specific.  Your distribution should be doing this for you, check their site.