If you suspect an error in the OPEN/CLOSE/EOV component and you can recreate the problem, you can create an optional work area trace to help with diagnosis. The work area trace traces the DCB and the O/C/EOV work area and extended work area associated with the DCB. It also includes a record of the address of the WTG table and the address of the current entry in the WTG table after each O/C/EOV module executes.
If you start GTF, use the TRACE=USR option. Refer to Abend error recording initiated by O/C/EOV for more information.
Figure 1 shows the GTF output resulting from activating the optional work area trace. In this example, the Open routines abnormally terminated the task because the format-1 DSCB for the data set could not be found. The associated system and return codes are 213-04. The trace record in Figure 1 includes a copy of the DCB, a copy of the O/C/EOV main work area associated with the DCB, various fields from the main work area, and the WTG table. This record will appear several times in the GTF output, once each time an Open object module has been given control.
Because the optional work area trace increases execution time considerably and produces copious output, it should be used only when other diagnostic techniques fail.