Creating the log file

For debugging sessions in full-screen mode, you can create a log file in one of the following ways:
  • Automatically by using the EQAOPTS LOGDSN and LOGDSNALLOC commands. This method helps new z/OS® Debugger users automatically create a log file. To learn how to specify EQAOPTS commands, see the topic EQAOPTS commands in the IBM® z/OS Debugger Reference and Messages or IBM z/OS Debugger Customization Guide.

    If you are an existing user that saves settings in a SAVESETS data set, z/OS Debugger does not create a new log file for you because the SAVESETS data set contains a SET LOG command. z/OS Debugger uses the log file specified in that SET LOG command.

  • Manually as described in this topic.
For debugging sessions in batch mode, manually create the log file as described in this topic.
To create a permanent log of your debug session, first create a file with the following specifications:
  • RECFM(F) or RECFM(FB) and 32<=LRECL<=256
  • RECFM(V) or RECFM(VB) and 40<=LRECL<=264
Then, allocate the file to the DD name INSPLOG in the CLIST, JCL, or EXEC you use to run your program.

For COBOL and LangX COBOL only, if you want to subsequently use the session log file as a commands file, make the RECFM FB and the LRECL equal to 72. z/OS Debugger ignores everything after column 72 for file input during a COBOL debug session.

For CICS® only, SET LOG OFF is the default. To start the log, you must use the SET LOG ON file command. For example, to have the log written to a data set named TSTPINE.DT.LOG , issue: SET LOG ON FILE TSTPINE.DT.LOG;.

Make sure the default of SET LOG ON is still in effect. If you have issued SET LOG OFF, output to the log file is suppressed. If z/OS Debugger is never given control, the log file is not used.

When the default log file (INSPLOG) is accessed during initialization, any existing file with the same name is overwritten. On MVS, if the log file is allocated with disposition of MOD, the log output is appended to the existing file. Entering the SET LOG ON FILE xxx command also appends the log output to the existing file.

If a log file was not allocated for your session, you can allocate one with the SET LOG command by entering: 
SET LOG ON FILE logddn;
This causes z/OS Debugger to write the log to the file which is allocated to the DD name LOGDDN.
Note: A sequential file is recommended for a session log since z/OS Debugger writes to the log file.
At any time during your session, you can stop information from being sent to a log file by entering: 
SET LOG OFF;
To resume use of the log file, enter: 
SET LOG ON;

The log file is active for the entire z/OS Debugger session.

z/OS Debugger keeps a log file in the following modes of operation: line mode, full-screen mode, and batch mode.