atexit函数的使用【学习笔记】

 #include "apue.h"

 static void my_exit1(void);
 static void my_exit2(void);

 int main(void)
 {
     int ret = -;

     ret = atexit(my_exit2);
     if(ret != )
         err_sys("can't not register my_exit2\r\n");

     ret = atexit(my_exit1);
     if(ret != )
         err_sys("can't not register my_exit1\r\n");

     ret = atexit(my_exit1);
     if(ret != )
         err_sys("can't not register my_exit1\r\n");

     printf("main done\r\n");

     exit();

 }

 static void my_exit1(void)
 {
     printf("first exit handler\r\n");
 }
 static void my_exit2(void)
 {
     printf("second exit handler\r\n");
 }