[lug] libraries...linking...learning...

[Anders Knudsen]

My system: RedHat 6.2, with 2.2.16 kernel.

Question/Advice: I am installing support for image creation with PHP. This 
requires gd, zlib, libpng, and libjpeg (for the formats I'm interested in.)
RedHat obviously already has these libs installed as rpms.
I want to remove the rpms and compile the libs, etc myself.
When I do this compile I will be installing them into /usr/local paths.
First I try to remove the rpms for gd, zlib, etc. I, of course, get module 
dependency errors. Now, I can force the removal, no prob there. What I'm 
dubious about is how do I let the system know where the new libs are? (I 
think they used to be in /usr/lib, or /lib.)
Is this a job for "ldconfig"? I am new to this stuff, so any pointers would 
be appreciated. FYI, I've already been thru compile and install of 
PHP/Apache/SSL/MySQL/mod_perl from source without any problems, so I'm not 
totally clueless ;-). This is my first time doing any library compiles tho.

Mucho TIA,

-anders.