Ok, this might be a bit lenghty I am sorry.
I'm about to go insane, google has offered no help, so I ask, someone
please save me from a brain bubble.

When compiling a few programs from source I get errors of this nature,
however the configure process completes without a hitch, this is during make:

(GCC 3.4)
lrealpath.c: In function `lrealpath':
lrealpath.c:110: warning: implicit declaration of function `pathconf'
lrealpath.c:110: `_PC_PATH_MAX' undeclared (first use in this function)
lrealpath.c:110: (Each undeclared identifier is reported only once
lrealpath.c:110: for each function it appears in.)
make[1]: *** [lrealpath.o] Error 1

(Libnet)
libnet_version.c: In function `__libnet_print_vers':
libnet_version.c:52: warning: implicit declaration of function `write'
libnet_version.c:52: `STDOUT_FILENO' undeclared (first use in this function)
libnet_version.c:52: (Each undeclared identifier is reported only once
libnet_version.c:52: for each function it appears in.)
make[1]: *** [libnet_version.o] Error 1

These are from public sources of programs that should be well coded, so
it has to be a problem with my server.

Here is my gcc -v output:

Reading specs from /usr/lib/gcc-lib/i386-slackware-linux/3.2.2/specs
Configured with: ../gcc-3.2.2/configure --prefix=/usr --enable-shared --enable-threads=posix --enable-__cxa_atexit --disable-checking --with-gnu-ld --verbose --target=i386-slackware-linux --host=i386-slackware-linux
Thread model: posix
gcc version 3.2.2

I am also using glibc 2.3.1, if anyone needs more information, please ask...

Thanks in advance!