www.pudn.com > 7_code.rar > experiment_1.c

/*exc.c实验一源码*/ 
#include  
#include  
#include  
#include  
#include  
int main(void) 
{ 
	pid_t child1,child2,child; 
/*创建两个子进程*/ 
	child1 = fork(); 
	child2 = fork(); 
/*子进程1的出错处理*/ 
	if( child1 == -1 ){ 
		perror("child1 fork"); 
		exit(1); 
	} 
/*在子进程1中调用execlp函数*/ 
	else if( child1 == 0 ){ 
		printf("In child1: execute 'ls -l'\n"); 
		if(execlp("ls","ls","-l",NULL)<0) 
			perror("child1 execlp"); 
	} 
/*子进程2的出错处理*/ 
	if( child2 == -1 ){ 
		perror("child2 fork"); 
		exit(1); 
	} 
/*在子进程2中使其暂停5秒*/ 
	else if( child2 == 0 ){ 
		printf("In child2: sleep for 5 seconds and then exit\n"); 
		sleep(5); 
		exit(0); 
	} 
/*在父进程中等待子进程2的退出*/ 
	else{ 
		printf("In father process:\n"); 
		do{ 
			child = waitpid( child2, NULL, WNOHANG ); 
			if( child ==0 ){ 
				printf("The child2 process has not exited!\n"); 
				sleep(1); 
			} 
		}while( child == 0 ); 
		if( child == child2 ) 
			printf("Get child2\n"); 
		else 
			printf("Error occured!\n"); 
	} 
}