PRINT121 changes MFX’s DCB default for the message data set to the following:
DCB=(LRECL=121,BLKSIZE=121,RECFM=FA)
This PARM is useful when the application includes a COBOL exit which uses DISPLAY, EXHIBIT, or TRACE instructions. (These macros will otherwise cause conflicts between program and sort/merge messages.) An alternative is provided by the MSGDD parameter, used to change the name of the MFX message data set.
The MFX program default for the message file’s DCB is:
DCB=(LRECL=125,BLKSIZE=882,RECFM=VBA)
If PRINT121 is set as an installation default, NOPRINT121 can be used as an override.
PRINT121 is automatically implemented for all program-initiated sort/merges.