C threads

hi I was using threads in C and this is first time i did this in C

but when I compile (actually I think in link time) it give me a error saying

:/home/shahan/engine_driver.c:43: undefined reference to `pthread_detach'

collect2: ld returned 1 exit status

make: *** [engine] Error 1

I used <pthread.h>

and functions pthread_create and pthread_detach

it mentioned a error for both these functions

can someone tell me why? I really need help in this

Thanx

[522 byte] By [shahan_123] at [2007-11-26 10:00:22]