Next: Typical A-task Message Sequence
Up: ADAM The Control Subsystem
Previous: Synchronisation
The TASK library maintains two lists in COMMON: the Current D-task Action Block
and the Active Subsidiary Task Action Block.
It also maintains the AST interrupt flag, indicating if
TASK_ASTSIGNAL() has been called.
The Current D-task Action Block holds details of the current D-task action,
i.e. the one on whose behalf the current call to ACT has been made.
Items held are:
- Action pointer for current action
- Message path resulting in current entry
- Message id resulting in current entry
- Context in message resulting in entry
- Status in message resulting in entry
- Context for current action
- Name code for current action
- Sequence number for current action
- Delay before next entry
- Request for rescheduling
- Current action name
- Action name in message
- Value string for current action
The Active Subsidiary Task Action Block holds details of active actions that
have been initiated in subsidiary tasks. If an incoming message corresponds to
one of the actions described in this common block, it will result in an entry
to ACT. Items held are (for each subsidiary action):
- Action pointer for initiating action (in this task)
- Message path for initiated action
- Message id for initiated action
Next: Typical A-task Message Sequence
Up: ADAM The Control Subsystem
Previous: Synchronisation
ADAM The Control Subsystem
Starlink System Note 77
A.J. Chipperfield
16 August 2001
E-mail:ussc@star.rl.ac.uk
Copyright © 2000 Council for the Central Laboratory of the Research Councils