PH67452: IBM MQ Z/OS: S0C4 ABEND IN CSQXCCAC FOLLOWING A CHANNEL ENDING ABNORMALLY 26/10/02 PTF PECHANGE

APAR status

• Closed as program error.

Error description

• An S0C4 abend occurs in CSQXCCAC following a multiplexed channel
  ending abnormally following an abend.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of IBM MQ for z/OS Version 9       *
  *                 Release 3 Modification 0 and Release 4       *
  *                 Modification 0.                              *
  ****************************************************************
  * PROBLEM DESCRIPTION: An S0C4-00000004 abend occurs in        *
  *                      CSQXCCAC after a multiplexed channel    *
  *                      ends abnormally due to an abend.        *
  ****************************************************************
  As part of cleaning up a multiplexed channel following an abend,
  a call is made on both the recieve and the async thread to free
  storage related to the abended multiplexed channel. This call
  was added by APAR PH58725. The call should only be made once by
  the recieve thread. The S0C4 abend addressed by this APAR
  occured due to the second attempt to free storage that was
  already freed.
  

Problem conclusion

• The code has been corrected so that the call added by APAR
  PH58725 is restricted to only run whilst on the recieve thread,
  thus preventing the second free attempt.
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

  PH72903 UO09811 UO09812

Modules/Macros

• CSQXRCAP
  

Fix information

• Fixed component name

  IBM MQ Z/OS V9

• Fixed component ID

  5655MQ900

Applicable component levels