C180_oyster_driver/test_app/mywatchdog.c

#include <fcntl.h>
#include <linux/kd.h>
#include <linux/vt.h>
#include <stdio.h>
#include <stdlib.h>
#include "gpioregs.h"

#define DEV_FILE  "/dev/watchdog"
int main(int argc, char *argv[])
{
	int fd;
	int retval=1;
	char args;
	/* char *voidptr = (char *) NULL; */
	char *ptr = argv[0];
	if (argc != 2) 
	{
		printf ("Usage: %s [on/off/status] \n", argv[0]);
		exit (-1);
	}

	if (strcmp(argv[1], "on") == 0)
		args = ON;
        else if (strcmp(argv[1], "off") == 0)
		args = OFF;
	else if (strcmp(argv[1], "status") == 0) 
	{
		if ((fd = open(DEV_FILE, O_RDONLY)) == -1) 
		{
               		 printf("%s: can't open /dev/watchdog\n", argv[0]);
                	return(-1);
        	}
        	if(read(fd, &args,1) == 1)
        	{
                        printf ("The watchdog is %s\n",args?"on":"off");
			printf ("The args value is %d\n", args);
        	}
        	else
		{
                	printf ("Could not read status from the %s\n", DEV_FILE);
        		close(fd);
        		return(-1);
		}
		close(fd);
		return (0);
	}
	else
	{
		printf ("Unrecognized command. \n");
		exit (-1);
	}
	 if ((fd = open(DEV_FILE, O_WRONLY)) == -1) {
                printf("%s: can't open /dev/writeprotect\n", argv[0]);
                return(-1);
        }
	
	if(write(fd, &args,1) == 1)
	{
			printf ("Watchdog turned %s successfully\n", argv[1]);
	}
	else
	{
		printf ("Could not write to the %s\n", DEV_FILE);
		close(fd);
		return(-1);
	}
	close(fd);
	return 0;
}