Initializing ECBs for entries from create macros

When an active ECB needs to create a second ECB to perform independently, it can issue one of the following create macros:

CREMC

Creates an independent ECB for immediate processing and adds it to the ready list.

CREDC

Creates an independent ECB for deferred processing and adds it to the deferred list.

CREXC

Creates an independent ECB for low-priority deferred processing and adds it to the deferred list.

CREEC

Creates an independent ECB for immediate or deferred processing and adds it to the ready list or the deferred list.

CRETC

Creates an independent ECB for activation after a specified interval of time.

SWISC TYPE=CREATE

Creates an independent ECB. If the specific I-stream was indicated on the call to the SWISC macro, the ECB will have an affinity for the I-stream specified; otherwise, it will not have an affinity for any initial I-stream.