IBM Support

PH66957: MIGRATION TO 5.6 FROM 5.4 CAUSING COMMAREA TO HAVE BLANKS FOR UNINITIALIZED VARIABLES.

A fix is available

Subscribe

You can track all active APARs for this component.

 

APAR status

  • Closed as program error.

Error description

  • Customer migrated from 5.4 to 5.6 and is facing an error caused
    by behavioral changes for unassigned values.
    
    In version 5.4 the DFHCOMMAREA holds low-values NULLS x'00' for
    uninitialized variables while in version 5.6 they are SPACES
    x'40' and this is causing an error that leads to abend 4038.
    

Local fix

  • As a workaround using the feature toggle of 32kcommarea:
    com.ibm.cics.dpl.32kcommarea=false.
    

Problem summary

  • ****************************************************************
    * USERS AFFECTED: All CICS Users.                              *
    ****************************************************************
    * PROBLEM DESCRIPTION: Transaction abend 4038 when processing  *
    *                      an EXEC CICS LINK request with COMMAREA *
    *                      LENGTH at least 24K.                    *
    ****************************************************************
    An EXEC CICS LINK request to a remote program, over an MRO
    CONNECTION, specifies a COMMAREA LENGTH of at least 24K.
    The COMMAREA was initialized to SPACES (x'40' characters) and
    the DATALENGTH of application data is less than the COMMAREA
    length.
    
    Even though DATALENGTH is specified on the EXEC CICS LINK
    command the whole COMMAREA is copied to the DFHCOMMAREA
    container and shipped in the DFHTRANSACTION channel.
    
    The remote program which receives the COMMAREA and processes the
    application data unexpectedly finds trailing SPACES instead of
    NULLS which leads to an abend.
    
    KEYWORDS: com.ibm.cics.dpl.32kcommarea
    

Problem conclusion

  • When DATALENGTH is specified on the EXEC CICS LINK command, CICS
    is changed to copy that length to the DFHCOMMAREA container with
    the rest being NULLS.
    

Temporary fix

Comments

APAR Information

  • APAR number

    PH66957

  • Reported component name

    CICS TS Z/OS V5

  • Reported component ID

    5655Y0400

  • Reported release

    300

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2025-06-13

  • Closed date

    2026-03-02

  • Last modified date

    2026-04-02

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

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

    PH69107 UO06998

Modules/Macros

  • DFHXFP   DFHXFQ
    

Fix information

  • Fixed component name

    CICS TS Z/OS V5

  • Fixed component ID

    5655Y0400

Applicable component levels

  • R300 PSY UO06998

       UP26/03/04 P F603

Fix is available

  • Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.

[{"Business Unit":{"code":"BU048","label":"IBM Software"},"Product":{"code":"SSGMGV","label":"CICS Transaction Server"},"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"5.6","Line of Business":{"code":"LOB70","label":"Z TPS"}}]

Document Information

Modified date:
02 April 2026