gcc and his standard-directorys?

[Erik Wasser]

Hello.

I've have a basic question about the gcc (my version is 2.95). Where
can I determinate the directory where the gcc will look for the
includes and the directorys for librarylinking. I know about the flags
-I and -L but there are always some standarddirectorys. Where can I
change the basic directorys?

Background: I have different versions of gcc on my computer and I want
to to separete them cleanly. Every version should use his own directory
for "include"ing and "link"ing.

Thx for your time.

-- 
So long... Fuzz