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VM64031

When APAR VM64031 is applied, the maximum allowable length for a CP Monitor APPLDATA buffer will now be '4012' bytes instead of the previous value of '4024' bytes.

The documentation for the Diagnose Code X'DC' in the CP Programming Services book (SC24-6084-02) section 1.2.43 changes as follows:

Under the BUFFER-LEN field the statement:

"The minimum value for BUFFER-LEN is 1; the maximum value is 4024."

"The minimum value for BUFFER-LEN is 1; the maximum value is 4012."

If a BUFFER-LEN greater than 4012 bytes is specified, Condition Code 1 will be returned along with a Return Code of 6 (X'06) in Ry.

Additionally, the 'Note:' for the BUFFER-LEN field should now read:

"The maximum figure is derived to provide minimal space in a 4KB page for the static portion (APLSDT_APHDR) of the monitor record, MRAPLSDT, the end-of-frame record, MRMTREOF, and a 12-byte control area record."

If you have applications which use the X'DC' Diagnose to create APPLDATA records and your BUFFER-LEN is greater than 4012 bytes, you will need to modify your application to use the new maximum value of 4012 bytes.