C libraries

[Erik Price]

I don't really know anything about software engineering in C (or C++), 
though I've used the language itself in the context of a college class.

I have recently encountered something called the Apache Portable Runtime 
library.  Would this be used in place of, say glibc, or in addition to? 
  And is the goal of something like this that you try to use it to the 
exclusion of other libraries as much as possible so that you can be 
assured that your program will work on any platform that is compatible 
with the Apache Portable Runtime?

I'm not really so much interested in the APR itself as I am in the whole 
notion of portable runtimes and issues facing people who want to develop 
in C.  I know there are some C programmers on this list.  These are not 
things that I have had to think much about, since I use Java where I 
work, but I am interested in learning more about C.

Thanks,


Erik