Accessing Main Storage: CORE › Convert PL/I Statement Numbers into Displacements

Convert PL/I Statement Numbers into Displacements

PL/I users who want to set breakpoints using hexadecimal offsets (displacements) need to use an offset calculated from the beginning of the main control section. There are two ways to get such offsets:

• Use the offset given in the Assembler like listing provided by the source listing option of the PL/I compiler. However, this listing is rather long.
• Use the offset listed in the Tables of Offsets and Statement Numbers portion of a PL/I listing for a statement. This offset is relative to the beginning of the machine code for the internal procedure. Then, calculate the offset relative to the main control section using the following CORE command:

  CORE=PGM=pgmname;+'procname'+offset
  

pgmname

Indicates the PPT ID of a PL/I program module. It must be followed by a semicolon and a plus sign.

procname

Indicates the name of an internal PL/I procedure as listed in the Tables of Offsets.

offset

Indicates a hexadecimal offset for a statement as listed in the Tables of Offsets and Statement Numbers.

This command accepts the offset for a statement as listed in the Tables of Offsets, and returns the hexadecimal value of the offset of that statement as counted from the beginning of the main control section. Use the returned value to set a breakpoint or to request a CORE display of the program code at that location.

Examples

An offset must be specified in the command. (Specify 0 as +0.)

CORE=PGM=TESTPROG;+'EDIT INPUT'+10

The named program must reside in main storage. If it does not, use the following command to load it:

CORE=LOAD=pgmname

When you are finished, use the following command to remove the program from main storage:

CORE=DLTE=pgmname