Linux--mmap实现进程间通信

服务端程序

#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/mman.h>
#include <string.h>
#include <fcntl.h>
#include <errno.h>
#include <sys/types.h>


int main(int argc, char **argv)
{
	static int couter = 0;
	if (argc != 2)
	{
		PRintf("usage: %s file_name\n", argv[0]);
		return -1;
	}

	int fd = open(argv[1], O_CREAT | O_RDWR, 0744);
	if (fd < 0)
	{
		perror("open");
		return -1;
	}

	lseek(fd, 0x1000, SEEK_SET);
	write(fd, "\0", 1);

	char *mm = (char *)mmap(NULL, 0x1000, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
	if (mm == MAP_FAILED)
	{
		perror("mmap");
		return -1;
	}

	close(fd);
	while(1)
	{
		sprintf(mm, "%d[gzhang]", couter++);
	//	*mm = 'G';
		sleep(1);
	}

	munmap(mm, 0x1000);

	return 0;
}










客户端程序
#include <stdio.h>
#include <unistd.h>
#include <stdlib.h>
#include <sys/mman.h>
#include <fcntl.h>
#include <sys/mman.h>
#include <string.h>
#include <sys/types.h>
#include <errno.h>

int main(int argc, char **argv)
{
	if (argc != 2)
	{
		printf("usage: %s file_name\n", argv[0]);
		return -1;
	}

	int fd = open(argv[1], O_RDWR);
	if (fd < 0)
	{
		perror("open");
		return -1;
	}

	//lseek(fd, 0x1000, SEEK_SET);
	//write(fd, "\0", 1);

	char *mm = mmap(NULL, 0x1000, PROT_READ | PROT_WRITE, MAP_SHARED, fd, 0);
	if (!mm)
	{
		printf("mmap error\n");
		return -1;
	}

	close(fd);
	while(1)
	{
		printf("get [%s]\n", mm);
		sleep(1);
	}

	munmap(mm, 0x1000);

	return 0;
}