app.c

适用于初学者的源码,简单的字符型设备的驱动源码,

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

#include "scull.h"  /* 包含命令定义 */

int main()
{
	int fd = 0;
	int cmd;
	int arg = 0;
	char Buf[4096];
	
	
	/*打开设备文件*/
	fd = open("/dev/scull0",O_RDWR);
	if (fd < 0)
	{
		printf("Open Dev Scull0 Error!\n");
		return -1;
	}
	
	/* 调用命令SCULL_IOCPRINT */
	printf("<--- Call SCULL_IOCPRINT --->\n");
	cmd = SCULL_IOCPRINT;
	if (ioctl(fd, cmd, &arg) < 0)
        {
        	printf("Call cmd SCULL_IOCPRINT fail\n");
        	return -1;
	}
	
	
	/* 调用命令SCULL_IOCSETDATA */
	printf("<--- Call SCULL_IOCSETDATA --->\n");
	cmd = SCULL_IOCSETDATA;
	arg = 2007;
	if (ioctl(fd, cmd, &arg) < 0)
        {
        	printf("Call cmd SCULL_IOCSETDATA fail\n");
        	return -1;
	}

	
	/* 调用命令SCULL_IOCGETDATA */
	printf("<--- Call SCULL_IOCGETDATA --->\n");
	cmd = SCULL_IOCGETDATA;
	if (ioctl(fd, cmd, &arg) < 0)
        {
        	printf("Call cmd SCULL_IOCGETDATA fail\n");
        	return -1;
	}
	printf("<--- In User Space SCULL_IOCGETDATA Get Data is %d --->\n\n",arg);
	
	
	close(fd);
	return 0;	
}