fork wait

如果父程式先結束，子程式不會自己結束

#include<stdio.h>
#include<stdlib.h>
#include<sys/wait.h>
int main(){
        int a,b,c;
        if(a = fork()){
                printf("fork1---%ld\n",a);
                int stat;
                //等待子程式結束
                pid_t child_pid = wait(&stat);

                if(WIFEXITED(stat)){
                        printf("exited with code %d\n",WEXITSTATUS(stat));
                }
        }else{
                printf("I'm child\n");
        }
        //int stat;
        //pid_t child_pid = wait(&stat);

        //if(WIFEXITED(stat)){
        //      printf("exited with code %d\n",WEXITSTATUS(stat));
        //}

        return 0;
}