Starting GTF with trace output to an existing data set on tape

Figure 1 shows how the START command is used to direct GTF trace output to an existing data set on tape rather than to an existing data set on a DASD. The device type and volume serial number are supplied. The disposition and name of the trace data set are changed from DISP=(NEW,KEEP) and DSNAME=SYS1.TRACE to DISP=(OLD,KEEP) and DSNAME=TPOUTPUT. The specified tape has a volume serial of TRCTAP and resides on a 3400 tape drive. Note that the GTFPARM parmlib member is used to specify the trace options.

Here the GTF keyword is not followed by a unique identifer and defaults to volume serial number.

Figure 1. Example: Start GTF, trace output to an existing data set on tape

START GTF,3400,TRCTAP,(MODE=EXT),DISP=OLD,DSNAME=TPOUTPUT
 
AHL103I TRACE OPTIONS SELECTED--SYSM,DSP,PCI,SRM,TRC,USR
 
00 AHL125A RESPECIFY TRACE OPTIONS OR REPLY U
 
REPLY 00,U
 
AHL031I GTF INITIALIZATION COMPLETE