linux下的线程学习（二）

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

 void cleanup(void *arg) {

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

 void* thr_fn1(void *arg) {

   printf("thread1 start\n");
   pthread_cleanup_push(cleanup, (void*)"thread 1 first handler");
   pthread_cleanup_push(cleanup, (void*)"thread 1 second handler");
   printf("thread1 push complete.\n");

   if(arg) {
     return ((void*));
   }

   pthread_cleanup_pop();
   pthread_cleanup_pop();

   return ((void*));
 }

 void* thr_fn2(void *arg) {

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

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

   pthread_cleanup_pop();
   pthread_cleanup_pop();

   pthread_exit((void*));
 }

 int main() {

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

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

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

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

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

   return ;
 }

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