linux下的线程学习（二）

#include <iostream>
#include <pthread.h>

void cleanup(void *arg) {

  printf("cleanup: %s
", (char*)arg);
}

void* thr_fn1(void *arg) {
  
  printf("thread1 start
");
  pthread_cleanup_push(cleanup, (void*)"thread 1 first handler");
  pthread_cleanup_push(cleanup, (void*)"thread 1 second handler");
  printf("thread1 push complete.
");
  
  if(arg) {
    return ((void*)1);
  }

  pthread_cleanup_pop(1);
  pthread_cleanup_pop(1);

  return ((void*)1);
}

void* thr_fn2(void *arg) {
  
  printf("thread2 start
");
  pthread_cleanup_push(cleanup, (void*)"thread 2 first handler");
  pthread_cleanup_push(cleanup, (void*)"thread 2 second handler");
  printf("thread2 push complete.
");

  if(arg) {
    pthread_exit((void*)2);
  }

  pthread_cleanup_pop(1);
  pthread_cleanup_pop(1);

  pthread_exit((void*)2);
}

int main() {

  int err;
  pthread_t tid1,tid2;
  void *tret;

  err = pthread_create(&tid1, NULL, thr_fn1, NULL);
  if(err != 0)
    printf("can't create thread 1: %s
", strerror(err));

  err = pthread_create(&tid2, NULL, thr_fn2, NULL);
  if(err != 0)
    printf("can't create thread 2: %s
", strerror(err));

  err = pthread_join(tid1, &tret);
  if(err != 0)
    printf("can't join with thread 1: %s
", strerror(err));
  printf("thread 1 exit code %d
", (int*)tret );

  err = pthread_join(tid2, &tret);
  if(err != 0)
    printf("can't join with thread 2: %s
", strerror(err));
  printf("thread 2 exit code %d
", (int*)tret );

  return 0;
}

使用pthread_cleanup_push pthread_cleanup_pop完成线程退出函数自动调用的功能;