i am a newb to linux and i've been trying to update my pkgconfig without much success. i'm running redhat 9 and after i type ./configure i try to type make and these are the errors i get:

[root@localhost pkgconfig-0.15.0]# make
make all-recursive
make[1]: Entering directory `/root/pkgconfig-0.15.0'
Making all in glib-1.2.8
make[2]: Entering directory `/root/pkgconfig-0.15.0/glib-1.2.8'
make all-recursive
make[3]: Entering directory `/root/pkgconfig-0.15.0/glib-1.2.8'
Making all in .
make[4]: Entering directory `/root/pkgconfig-0.15.0/glib-1.2.8'
/bin/sh ./libtool --mode=compile gcc -DHAVE_CONFIG_H -I. -I. -I. -DG_LOG_DOMAIN=g_log_domain_glib -g -O2 -Wall -c gmain.c
mkdir .libs
gcc -DHAVE_CONFIG_H -I. -I. -I. -DG_LOG_DOMAIN=g_log_domain_glib -g -O2 -Wall -c gmain.c -fPIC -DPIC -o .libs/gmain.lo
gmain.c:191: error: `poll' undeclared here (not in a function)
gmain.c: In function `g_get_current_time':
gmain.c:597: warning: implicit declaration of function `gettimeofday'
gmain.c: In function `g_main_poll':
gmain.c:980: warning: implicit declaration of function `pipe'
gmain.c:1079: warning: implicit declaration of function `read'
gmain.c: In function `g_main_set_poll_func':
gmain.c:1211: error: `poll' undeclared (first use in this function)
gmain.c:1211: error: (Each undeclared identifier is reported only once
gmain.c:1211: error: for each function it appears in.)
gmain.c: In function `g_main_wakeup':
gmain.c:1226: warning: implicit declaration of function `write'
make[4]: *** [gmain.lo] Error 1
make[4]: Leaving directory `/root/pkgconfig-0.15.0/glib-1.2.8'
make[3]: *** [all-recursive] Error 1
make[3]: Leaving directory `/root/pkgconfig-0.15.0/glib-1.2.8'
make[2]: *** [all-recursive-am] Error 2
make[2]: Leaving directory `/root/pkgconfig-0.15.0/glib-1.2.8'
make[1]: *** [all-recursive] Error 1
make[1]: Leaving directory `/root/pkgconfig-0.15.0'
make: *** [all-recursive-am] Error 2
[root@localhost pkgconfig-0.15.0]#

i conclude this is also causing the pkg config path error i get because i'm trying to upgrade glib and gtk. help would greatly be appreciated.

I fixed this by editing gmain.c and changing <sys/poll.h> to <poll.h> and removing the #IFDEF's around it. I then went on to get nessus running sucessfully after this. This may fix your problem as well.