Deferred LDDs

As described in the previous section, you can use the LDD command to identify a CU as an assembler CU before the CU has become known to z/OS® Debugger. This is known as a deferred LDD. In this case, whenever the CU appears, it is immediately marked as an assembler CU and an attempt is made to load the debug data from the default data set name or from the data set currently specified by SET DEFAULT LISTINGS.

If the debug data cannot be found in this way, you must using the SET SOURCE or SET DEFAULT LISTINGS command after the CU appears to cause the debug data to be loaded from the correct data set. You can do this using a command such as:

AT APPEARANCE mycu SET SOURCE (mycu) hlq.qual1.dsn

Alternatively, you might wait until you have stopped for some other reason after "mycu" has appeared and then use the SET SOURCE or SET DEFAULT LISTING commands to direct z/OS Debugger to the proper data set.