process1.c

数据结构学习点滴

#include "myhdr.h"

int
main()
{
	pid_t pid;
	int rv;
	switch(pid=fork())
	{
		case -1:
			perror("fork error");
			exit(1);
		case 0: 
			sleep(2);
			printf("CHILD:this is a child process\n");
			printf("CHILD:my PID is:%d\n",getpid());
			printf("CHILD:my user PID is:%d\n",getuid());
			printf("CHILD:my parent PID is:%d\n",getppid());
			printf("CHILD:enter my exit status\n");
			scanf("%d",&rv);
			printf("i am exit now!\n");
			exit(rv);
		default:
			printf("PARENT:this is a parent process\n");
			printf("PARENT:my PID is:%d\n",getpid());
	        	printf("PARENT:my user PID is:%d\n",getuid());  
			printf("PARENT:my child's PID is:%d\n",pid);
			printf("PARENT:i am now waiting my child exit...\n");
			wait(&rv);
	printf("PARENT: my child's exit status is:%d\n",WEXITSTATUS(rv));	
			printf("PARENT:i am exit now\n");
	}
	return 0;
}