comp.os.linux.networking

Hi all,
I have a couple questions:
1. Where exactly in the glibc soouce code are the functions for the
socket api found (It seems to me like everything in soxket/ is a
stub).
2. I have compiled and installed an older version of glibc (from 2.7
to 2.5.1) with the prefix=/usr. I see both libraries in /lib, and I
have run /sbin/ldconfig. But it seems like everything is still linked
up with the previous library that I have (for example the libc.so.6
and ld-linux.2.so still have symlinks to the 2.7, and not the 2.5.1 I
installed. How do I make the system aware of that.
[What I am trying to do is modify some socket functions in glibc and
install it, for a school class project].
Thanks,