Anonymous - 2003-05-01

Hi, I am a newbie on Unix.
I get following error when running make:
/usr/ccs/bin/ld: Unsatisfied symbols:
   sem_post (first referenced in threader.o) (code)
   sem_wait (first referenced in threader.o) (code)
   sem_init (first referenced in threader.o) (code)
*** Error exit code 1
What can I do?