APUE 有关exec() Functions的程序出错，不知道为什么？！
Figure 8.16程序如下

#include <apue.h>

#include <sys/wait.h>



char * env_init[] = {"USER=unknow","PATH=/tmp",NULL};

int main(void)

{

        pid_t pid;

        if((pid=fork())<0)

        {

                printf("fork error\n");

        }

        else if(pid == 0)

        {

                if(execle("/home/zhuhaichao/apue练习/8.17“,”8.17“,”mysql","MY ARG2",(char *) 0,env_init)<0)

                printf("execute error\n");                   //我就把pathname改了，要执行的可执行文件8.17在这个目录下

        }

        if(waitpid(pid,NULL,0)<0)

        {

                printf("wait error\n");

        }

  if((pid=fork())<0)

        {

                printf("fork error\n");

        }



        else if(pid == 0)

                {

                         if(execlp("8.17","8.17","only 1 arg",(char *) 0)<0)

                        {

                                printf("exec error\n");

                        }

                }



        exit(0);

但是执行的结果是：execute error
                                wait error
                               $
                                exec error
                                exec