w_init Kernel Service
Purpose
Registers a watchdog timer with the kernel.
Syntax
#include <sys/types.h>
#include <sys/errno.h>
#include <sys/watchdog.h>int w_init ( w)
struct watchdog *w;
struct watchdog *w;
Parameter
| Item | Description |
|---|---|
| w | Specifies the watchdog timer structure. |
Description
The watchdog structure
must be initialized prior to calling the w_init kernel service
as follows:
- Set the next and prev fields to NULL.
- Set the func and restart fields to the appropriate values.
- Set the count field to 0.
Attention: The watchdog structure must be pinned when the w_init service is called. It must remain pinned until after the call to the w_clear service. During this time, the watchdog structure must not be altered except by the watchdog services.
The watchdog timer services, including the w_init kernel service, are typically used to verify that an I/O operation completes in a reasonable time. The watchdog timer is initialized to the stopped state and must be started using the w_start service.
In both uniprocessor and multiprocessor environments, the w_init kernel service always succeeds.
The calling parameters for the watchdog timer function are:
void func (w)
struct watchdog *w;Execution Environment
The w_init kernel service can be called from the process environment only.
Return Values
The w_init kernel service returns 0 for compatibility with previous releases of AIX®.