xref: /OK3568_Linux_fs/kernel/samples/watchdog/watchdog-simple.c (revision 4882a59341e53eb6f0b4789bf948001014eff981) 
1*4882a593Smuzhiyun // SPDX-License-Identifier: GPL-2.0
2*4882a593Smuzhiyun #include <stdio.h>
3*4882a593Smuzhiyun #include <stdlib.h>
4*4882a593Smuzhiyun #include <unistd.h>
5*4882a593Smuzhiyun #include <fcntl.h>
6*4882a593Smuzhiyun 
main(void)7*4882a593Smuzhiyun int main(void)
8*4882a593Smuzhiyun {
9*4882a593Smuzhiyun 	int fd = open("/dev/watchdog", O_WRONLY);
10*4882a593Smuzhiyun 	int ret = 0;
11*4882a593Smuzhiyun 	if (fd == -1) {
12*4882a593Smuzhiyun 		perror("watchdog");
13*4882a593Smuzhiyun 		exit(EXIT_FAILURE);
14*4882a593Smuzhiyun 	}
15*4882a593Smuzhiyun 	while (1) {
16*4882a593Smuzhiyun 		ret = write(fd, "\0", 1);
17*4882a593Smuzhiyun 		if (ret != 1) {
18*4882a593Smuzhiyun 			ret = -1;
19*4882a593Smuzhiyun 			break;
20*4882a593Smuzhiyun 		}
21*4882a593Smuzhiyun 		sleep(10);
22*4882a593Smuzhiyun 	}
23*4882a593Smuzhiyun 	close(fd);
24*4882a593Smuzhiyun 	return ret;
25*4882a593Smuzhiyun }
26