shell_pipe.c

linux下有命管道和无名管道的使用。以及管道读写规则

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




int main(int argc,char *argv[])
{
	int fd[2];
	pid_t child;
	pipe(fd);
	child=fork();
	char r_buffer[8192];
	int read_count=0;
	if(child==0)
	{
		close(fd[0]);
		//close(1);
		dup2(fd[1],1);
		close(fd[1]);
		execlp("cat","cat","/etc/passwd",0);
	}
	else if(child>0)
	{
		close(fd[1]);
		while( (read_count=read(fd[0],r_buffer,sizeof(r_buffer)))>0)
		{
			printf("%s\n",r_buffer);
		}
	}
	return 0;
}