Glossary

Access method control block (ACB)

A control block that links an application to a VSAM data set

Active control data set (ACDS)

A VSAM linear data set that controls the storage management policy for an installation. It is shared by each system that is using the same SMS configuration to manage storage.

Active lock

A lock obtained by an executing subsystem. Requests for locks incompatible with a held active lock are queued.

See also [Retained lock]
Alternate index

A key-sequenced data set containing index entries organized by the alternate keys of its associated base data records. It provides an alternative way of locating records in the data set on which the alternate index is based.

Application owning region (AOR)

A CICS region that ...

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