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    1: /*
    2:  * pthread.c:
    3:  * Tiny test program to see whether POSIX threads work.
    4:  */
    5: 
    6: static const char rcsid[] = "$Id: pthread.c,v 1.1.1.1 2012/02/21 16:57:34 misho Exp $";
    7: 
    8: #include <sys/types.h>
    9: 
   10: #include <errno.h>
   11: #include <pthread.h>
   12: #include <stdio.h>
   13: #include <string.h>
   14: #include <time.h>
   15: #include <unistd.h>
   16: 
   17: static pthread_mutex_t mtx = PTHREAD_MUTEX_INITIALIZER;
   18: static pthread_cond_t cond = PTHREAD_COND_INITIALIZER;
   19: static int return_value = -1;
   20: 
   21: void *worker_thread(void *v) {
   22:     /* Record successful return and signal parent to wake up. */
   23:     return_value = 0;
   24:     pthread_mutex_lock(&mtx);
   25:     pthread_cond_signal(&cond);
   26:     pthread_mutex_unlock(&mtx);
   27:     while (1) {
   28:         sleep(1);
   29:         pthread_testcancel();
   30:     }
   31: }
   32: 
   33: /* Start a thread, and have it set a variable to some other value, then signal
   34:  * a condition variable. If this doesn't happen within some set time, we assume
   35:  * that something's gone badly wrong and abort (for instance, the thread never
   36:  * got started). */
   37: int main(void) {
   38:     pthread_t thr;
   39:     int res;
   40:     struct timespec deadline = {0};
   41:     if ((res = pthread_mutex_lock(&mtx)) != 0
   42:         || (res = pthread_create(&thr, NULL, worker_thread, NULL)) != 0) {
   43:         fprintf(stderr, "%s\n", strerror(res));
   44:         return -1;
   45:     }
   46: 
   47:     /* Thread should now be running; we should wait on the condition
   48:      * variable. */
   49:     do
   50:         deadline.tv_sec = 2 + time(NULL);
   51:     while ((res = pthread_cond_timedwait(&cond, &mtx, &deadline)) == EINTR);
   52:     
   53:     if (res != 0) {
   54:         fprintf(stderr, "%s\n", strerror(res));
   55:         return -1;
   56:     }
   57: 
   58:     if ((res = pthread_cancel(thr)) != 0
   59:         || (res = pthread_join(thr, NULL)) != 0) {
   60:         fprintf(stderr, "%s\n", strerror(res));
   61:         return -1;
   62:     }
   63:     
   64:     return return_value;
   65: }