The inquiry routines TASK_GET_REASON and TASK_GET_MESSINFO return a value in one of two groups. The first group concerns reschedules caused by events in this task.
| MESSYS__RESCHED | a timer has expired |
| MESSYS__ASTINT | an AST routine has been obeyed |
| MESSYS__KICK | the action has been ‘kicked’ |
The second group concerns messages received from a subsidiary task.
| MESSYS__TRIGGER | a trigger message has arrived, the subsidiary action |
| continues | |
| DTASK__ACTCOMPLETE | the subsidiary action completed successfully |
| DTASK__ACTINFORM | the subsidiary action completed with an error |
| DTASK__ACTCANCEL | the subsidiary action was cancelled |
| DTASK__IVACTSTAT | the subsidiary action completed with an illegal REQUEST |
In addition, the value can be any error status returned by the action in the subsidiary task.