fifo_bw.c

关于进程间通信的代码集锦2

#include <sys/types.h>
#include <sys/stat.h>
#include <errno.h>
#include <fcntl.h>
#define FIFO_SERVER "/tmp/fifoserver"

int main(int argc,char** argv)
{
	int fd;
	char w_buf[4096*2];
	int real_wnum;
	memset(w_buf,0,4096*2);
	if((mkfifo(FIFO_SERVER,O_CREAT|O_EXCL)<0)&&(errno!=EEXIST))
	{
		printf("cannot create fifoserver\n");
	}
	fd=open(FIFO_SERVER,O_WRONLY,0);
	if(fd==-1)
	{
		if(errno==ENXIO)
		{
			printf("open error:no reading process.\n");
		}
	}
	real_wnum=write(fd,w_buf,4000);
	if(real_wnum==-1)
	{
		if(errno==EAGAIN)
		{
			printf("write to fifo error. try later\n");
		}
	}
	else
	{
		printf("real write num is %d\n",real_wnum);
	}/*
	real_wnum=write(fd,w_buf,88000);
	if(real_wnum==-1)
	{
		if(errno==EAGAIN)
		{
			printf("try later.\n");
		}
	}
	else
	{
		printf("real write num is %d\n",real_wnum);
	}*/
	printf("write over\n");
	return 0;
}