#include <stdio.h> #include <stdlib.h> #include <pthread.h> #define THREAD_NUM 10 void *test(void *args) {  printf("tid %d: i say 'Hello'.\n", args);  return NULL; } int main() {  int i, err;  pthread_t child[THREAD_NUM];  for(i = 0; i < THREAD_NUM; i++) {   printf("Creating thread %d\n", i);   err = pthread_create(&child[i], NULL, test, (void *) i);   if(err) {    printf("Can't create thread %d\n", i);    exit(0);   }  }  for(i = 0; i < THREAD_NUM; i++)  pthread_join(child[i], NULL);  printf("Thread initialize\n");  return 0; }