in_transition()
Wait for a PSL object to change state.
Syntax
Parameter
Parameter | Definition |
|---|---|
object | name of the object that is being checked for transition between states |
timeout | time in seconds that is allowed for the transition between states |
Description
When first called, the in_transition() function sets a timer equal to timeout seconds on application instance object. While the timer is running, subsequent in_transition() function calls return FALSE.
After the timer has expired, calls to the in_transition() function continue to return FALSE until the next full discovery cycle, at which time the in_transition() function will return TRUE and reset the timer. The timer is also reset by calls to the PSL change_state() function. (For more information, see change_state().)
The in_transition() function sets the errno variable when there is a problem finding the instance specified by the objectparameter. The in_transition() function sets the errno variable under the following conditions:
errno Value | Description |
|---|---|
12 | E_PSL_CREATE_EMPTY |
13 | E_PSL_CREATE_EMPTY_SYMBOL_TABLE |
14 | E_PSL_CREATE_INTERNAL_FAILURE |
15 | E_PSL_CREATE_INACTIVE_APPLICATION |
17 | E_PSL_CREATE_UNKNOWN_APPLICATION |
If an error occurs while looking up the instance the in_transition() function returns the NULL string ("").
Example
The following example uses the in_transition() function to set a 3-minute timer against the ORACLE database instance dev, and when the timer expires, the in_transition() function waits for the next full discovery cycle and changes the state of dev to ALARM:
# Wait to make sure that the database is not
# in the middle of a startup or shutdown.
if (!in_transition ("/ORACLE/dev", 180))
{
change_state("/ORACLE/dev",ALARM,"Database has crashed.");
}