app.c

这个是linux下的一个字符设备的驱动程序

#include <stdio.h>
#include <string.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>

#define filename "/dev/akae"

int main(void)
{
	int fd;
	char buf[100];
	int ret_w,ret_r;

	fd = open(filename,O_RDWR);

	if (fd < 0)
	{
		printf("open %s file error,please use sudo?",filename);
		return -1;
	}
	//while (1)
	{
		fgets(buf,100,stdin);
		printf("buf1 = %s\n",buf);

		ret_w = write(fd,buf,strlen(buf));
		printf("ret_w = %d,buf2 = %s\n",ret_w,buf);

		ret_r = read(fd,buf,ret_w);
		printf("ret_r = %d,buf3 = %s\n",ret_r,buf);
	}
	close(fd);

	return 0;
}