piperw.c

ARM Linux2.4 进程间通信 非常好

/*********************************************************************
* File：		piperw.c
* Author：	Embest	J.Zhao	2005.2.17
* Desc：		use pipes
* History：
*********************************************************************/

#include <unistd.h>
#include <stdio.h>
#include <stdlib.h>
#include <asm/limits.h>

#define BUF_SIZE PIPE_BUF

int main(void)
{
	int nFd[2];						/* Array for the pipe */
	int nPid, nLen;
	char szBuf[BUF_SIZE];
		
	/* Create pipe */
	if ((pipe(nFd)) < 0)
	{
		printf("create pipe error.\n");
		exit(0);
	}
	
	/* fork */
	if ((nPid = fork()) < 0)
	{
		printf("fork error.\n");
		exit(-1);
	}		
	if (nPid == 0)
	{
		/* child open the read descriptor, close the write descriptor */
		close (nFd[0]);
		write (nFd[1], "message\n", 8);
		close (nFd[1]);
		exit(0);
	}
	else
	{
		close (nFd[1]);
		while ((nLen = read(nFd[0], szBuf, nLen)) > 0)
			write (STDOUT_FILENO, szBuf, nLen);
		close (nFd[0]);
	}

	waitpid(nPid, NULL, 0);
	return 0;
}