Moxa W321-LX [67/80] Ioctl fd wdioc_gettimeout timeout

W321/341 Linux Programmer's Guide

6-4

This example might actually print "The timeout was set to 60 seconds" if the device has a granularity of

minutes for its timeout.

3. Query the current timeout using the GETTIMEOUT ioctl.

ioctl(fd, WDIOC_GETTIMEOUT, &timeout);

printf("The timeout was is %d seconds\n", timeout);

Example 1:

* Watchdog Driver Test Program

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include <unistd.h>

#include <fcntl.h>

#include <sys/ioctl.h>

#include <linux/types.h>

#include <linux/watchdog.h>

int fd;

* This function simply sends an IOCTL to the driver, which in turn ticks

* the PC Watchdog card to reset its internal timer so it doesn't trigger

* a computer reset.

static void keep_alive(void)

{

int dummy;

ioctl(fd, WDIOC_KEEPALIVE, &dummy);

}

* The main program. Run the program with "-d" to disable the card,

* or "-e" to enable the card.

int main(int argc, char *argv[])

{

int flags, get_timeout = 0;

int set_timeout = 60;

fd = open("/dev/watchdog", O_WRONLY);

if (fd == -1) {

fprintf(stderr, "Watchdog device not enabled.\n");

fflush(stderr);

exit(-1);