[WATCHDOG] Pre-Timeout flags

    ioctl(fd, WDIOC_GETTIMEOUT, &timeout);

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

Envinronmental monitoring:

Pretimeouts:

Some watchdog timers can be set to have a trigger go off before the

actual time they will reset the system.  This can be done with an NMI,

interrupt, or other mechanism.  This allows Linux to record useful

information (like panic information and kernel coredumps) before it

resets.

    pretimeout = 10;

    ioctl(fd, WDIOC_SETPRETIMEOUT, &pretimeout);

Note that the pretimeout is the number of seconds before the time

when the timeout will go off.  It is not the number of seconds until

the pretimeout.  So, for instance, if you set the timeout to 60 seconds

and the pretimeout to 10 seconds, the pretimout will go of in 50

seconds.  Setting a pretimeout to zero disables it.

There is also a get function for getting the pretimeout:

    ioctl(fd, WDIOC_GETPRETIMEOUT, &timeout);

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

Not all watchdog drivers will support a pretimeout.

Environmental monitoring:

All watchdog drivers are required return more information about the system,

some do temperature, fan and power level monitoring, some can tell you

	WDIOF_SETTIMEOUT	Can set/get the timeout

The watchdog can do pretimeouts.

	WDIOF_PRETIMEOUT	Pretimeout (in seconds), get/set

For those drivers that return any bits set in the option field, the

GETSTATUS and GETBOOTSTATUS ioctls can be used to ask for the current

#define	WDIOC_KEEPALIVE		_IOR(WATCHDOG_IOCTL_BASE, 5, int)

#define	WDIOC_SETTIMEOUT        _IOWR(WATCHDOG_IOCTL_BASE, 6, int)

#define	WDIOC_GETTIMEOUT        _IOR(WATCHDOG_IOCTL_BASE, 7, int)

#define	WDIOC_SETPRETIMEOUT	_IOWR(WATCHDOG_IOCTL_BASE, 8, int)

#define	WDIOC_GETPRETIMEOUT	_IOR(WATCHDOG_IOCTL_BASE, 9, int)

#define	WDIOF_UNKNOWN		-1	/* Unknown flag error */

#define	WDIOS_UNKNOWN		-1	/* Unknown status error */

#define WDIOF_POWEROVER		0x0040	/* Power over voltage */

#define WDIOF_SETTIMEOUT	0x0080  /* Set timeout (in seconds) */

#define WDIOF_MAGICCLOSE	0x0100	/* Supports magic close char */

#define	WDIOF_PRETIMEOUT	0x0200  /* Pretimeout (in seconds), get/set */

#define	WDIOF_KEEPALIVEPING	0x8000	/* Keep alive ping reply */

#define	WDIOS_DISABLECARD	0x0001	/* Turn off the watchdog timer */