CICS frozen ACF2 CICS source exit ACFAESXC issuing EXEC CICS INQUIRE TSQUEUE custom code

Products

• ACF2 - z/OS

Issue/Introduction

User written code added to sample acf2 exits module ACFAESXC caused CICS region to freeze.
Customer added EXEC CICS INQUIRE TSQUEUE.

Cause

Issuing EXEC CICS INQUIRE TSQUEUE caused CICS to freeze because of a blank or zero EIBTRMID (terminal id) 

Resolution

Prior to issuing EXEC CICS INQUIRE TSQUEUE code should test that there is a valid terminal specified.

        TM    EIBTRMID,X'BF'     BLANK OR ZEROS?                   

         BZ    RETURN                YES,NEVER MIND