When using Datacom Multi-User (MUF) startup option SYSOUT, the PXX snaps, diagnostics, and traces are redirected to the SYSOUT class instead of to the physical PXX data set.
How to test that Datacom SYSOUT startup option is sending output to a SYSOUT class instead of to the physical PXX data set?
z/OS
One way to test that output is being written to a SYSOUT class is to issue a SNAP console command to the Datacom Multi-User (MUF). SNAP will force the Master list to be written to PXXMLnn:
/f mufstc,SNAP
Notice that the content of the SYSOUT class identified as PXXMLnn contains the Master List. Then to clear the CLRMLnn sysout:
/f mufstc,CLRML
The SNAP can also be issued using batch DBUTLTY command:
COMM OPTION=SNAP
The clear can also be issued using batch DBUTLTY command:
COMM OPTION=CLRML
Refer to Datacom Core - 15.1 section SYSOUT on directing PXX snaps, diagnostic, and traces in z/OS.
Refer to Datacom Core - 15.1 section COMM CLRnnn (Reset Alternate Output Data Sets)
Refer to Datacom Core - 15.1 section COMM SNAP (Write Dump of Master List)