pthread_create.c

   1 #include <stdio.h>
   2 #include <stdlib.h>
   3 #include <pthread.h>
   4
   5 #define NUM_THREADS 20
   6
   7 /* function prototypes */
   8 void *threadfun(void *arg);
   9
  10 int main() {
  11    pthread_t tid[NUM_THREADS];
  12    int i, cnt[NUM_THREADS];
  13
  14    for (i=0; i<NUM_THREADS; i++) {
  15       cnt[i] = i;
  16       printf("Creating thread: %d\n", i);
  17       if (pthread_create(&tid[i], NULL, threadfun, (void *)&cnt[i])) {
  18          fprintf(stderr, "pthread_create() error\n");
  19          exit(EXIT_FAILURE);
  20       }
  21    }
  22
  23    /* make sure all threads are done */
  24    for (i=0; i<NUM_THREADS; i++)
  25       if (pthread_join(tid[i], NULL)) {
  26          fprintf(stderr, "pthread_join() error\n");
  27          exit(EXIT_FAILURE);
  28       }
  29
  30    return EXIT_SUCCESS;
  31 }
  32
  33 void *threadfun(void *arg) {
  34    printf("Hello! I am thread: %d\n", *(int *) arg);
  35    pthread_exit(NULL);
  36 }