[ILUG] threads compilation problem

[Dave Airlie]

-lpthread

Dave.

On Wed, 15 Mar 2000, john carter wrote:

> hi
> when i compile the file below using gcc abthread.c I get the following type of errors .
> 
> /tmp/cc4WfL0U.o(.text+0x6b) undefined reference to pthread_create
> /tmp/cc4WfL0U.o(.text+0xd7) undefined reference to pthread_join
> 
> 
> any ideas
> thanks john 
> 
> 
> heres the file
> 
> /* Creates two threads, one printing 10000 "a"s, the other printing
>    10000 "b"s.
>    Illustrates: thread creation, thread joining. */
> 
> #include <stddef.h>
> #include <stdio.h>
> #include <unistd.h>
> #include <pthread.h>
> 
> void * process(void * arg)
> {
>   int i;
>   fprintf(stderr, "Starting process %s\n", (char *) arg);
>   for (i = 0; i < 10000; i++) {
>     write(1, (char *) arg, 1);
>   }
>   return NULL;
> }
> 
> int main(void)
> {
>   int retcode;
>   pthread_t th_a, th_b;
>   void * retval;
> 
>   retcode = pthread_create(&th_a, NULL, process, (void *) "a");
>   if (retcode != 0) fprintf(stderr, "create a failed %d\n", retcode);
>   retcode = pthread_create(&th_b, NULL, process, (void *) "b");
>   if (retcode != 0) fprintf(stderr, "create b failed %d\n", retcode);
>   retcode = pthread_join(th_a, &retval);
>   if (retcode != 0) fprintf(stderr, "join a failed %d\n", retcode);
>   retcode = pthread_join(th_b, &retval);
>   if (retcode != 0) fprintf(stderr, "join b failed %d\n", retcode);
>   return 0;
> }
> 
> 
> 
>  for jokes check out www.csn.ul.ie/~mtbclub/john/jokes 
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> 
> 

-- 
------------ David Airlie, David.Airlie at ul.ie,airlied at skynet --------
Telecommunications Research Centre, ECE Dept, University of Limerick \
http://www.csn.ul.ie/~airlied	-- Telecommunications Researcher      \
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