undefined reference to `sem_init'

Posted on 2006-10-29
Last Modified: 2012-06-21
#include <semaphore.h>
#include <unistd.h>

static sem_t count_sem;
int main(int argc, char* argv[]){

I get the following problem when I compile using gcc
/tmp/cc4Pal2o.o: In function `main':
contoller.c:(.text+0x29): undefined reference to `sem_init'
contoller.c:(.text+0x35): undefined reference to `sem_wait'
collect2: ld returned 1 exit status

What is the problem and how to correct it? (My platform is Linux Fedora Core 5. )
Question by:william007
LVL 53

Accepted Solution

Infinity08 earned 500 total points
ID: 17829588
you have to link in the library when compiling : try adding -lpthreads to the compile command

Author Comment

ID: 17853552

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