gtpc3m1a | Concepts and Structures |
An exit macro request (EXITC) is used to remove an Entry
from the TPF system. System resources held by the exiting Entry are
returned to the system for use by other Entries. Control is transferred
to the exit program either because an exit macro was issued or because of the
occurrence of a system error.
The exit program accomplishes the following:
- Disconnects from the ECB all programs associated with the Entry
- Releases all main storage blocks, identified in CBRWs, used by the Entry
- Releases all data records held by the Entry. A held data
record means the Entry was using the system conventions to prevent other
Entries from modifying the record. The system considers data records
held at exit time to be an error condition and sends an error message to the
computer console.
- Closes any tapes or unit record devices opened and assigned to the Entry
at the time the EXITC was issued
- Ensures that all I/O initiated by the Entry is completed
- Releases the ECB.