pipe_wdependr.c

关于进程间通信的代码集锦

#include <unistd.h>
#include <sys/types.h>
#include <errno.h>

int main()
{
	int pipe_fd[2];
	pid_t pid;
	char r_buf[4];
	char* w_buf;	
	int writenum;
	int cmd;
	
	memset(r_buf,0,sizeof(r_buf));
	if(pipe(pipe_fd)<0)
	{
		printf("pipe create error\n");
		return -1;
	}

	if((pid=fork())==0)
	{
		printf("In child process\n");
		close(pipe_fd[0]);
		close(pipe_fd[1]);
		sleep(10);
		exit(0);		
	}
	else if(pid>0)
	{
		sleep(1);
		printf("In parent process\n");
		//close(pipe_fd[0]);
		w_buf="111";
		if((writenum=write(pipe_fd[1],w_buf,4))==-1)
		{
			printf("write to pipe error\n");
		}
		else
		{
			printf("the bytes write to pipe is %d \n",writenum);
		}
		close(pipe_fd[1]);
	}
	
	return 0;
}