c typedef用法

 include "apue.h"
 include <sys/wait.h>

int (void)
{
    pid_t pid;

    if ((pid = fork()) < 0){
        err_sys("fork error");
    }else if (pid == 0){
        printf("child pid=%d, parentid=%dn", getpid(), getppid());
        if (execl("./echoall.py", "echoall.py", "myarg1",
        "MY ARG2", (char *)0) < 0)
        err_sys("execle error");
    }

    if (waitpid(pid, NULL, 0) < 0)
        err_sys("wait error");

    exit(0);
}