UNLOCK request processing

The UNLOCK request is used to release exclusive control obtained during a READ UPDATE (VSAM or BDAM) or WRITE MASSINSERT (VSAM only) request.

VSAM processing (including CICS®-maintained data tables):
  1. The VSWA for the operation is released, together with associated storage.
  2. An ENDREQ request is sent to VSAM. This releases exclusive control of the CI, if it is held, and frees any VSAM strings.

BDAM processing:
  1. A supervisor call (SVC 53) is issued to release BDAM exclusive control, if necessary.
  2. A FREEMAIN call is issued to release the FIOA.