Writing the exit in HLASM

The following considerations apply to writing the exit in HLASM:

• There is currently no sample exit written in HLASM. You will have to write this yourself.
• Use the HLASM register save, call and return macros provided by Language Environment®. The caller code in Z Data Tools is LE-enabled and assumes the callee is LE enabled.
• Use argument 1, referred to in the sample COBOL program as RAM-WORK-AREA-PTR, in all the calls to the exit so that Z Data Tools remembers the address of your root block of storage. You can set this to any value and Z Data Tools will remember it and provide it back to your exit on every call.
• Get memory during the INIT-RAM call and free all memory during the TERM-RAM call.
• Use the TEST sample COBOL program to call your HLASM exit routine and test it outside of Z Data Tools.