gtpi1m0s | System Installation Support Reference |
User exit routine UCCCMXF is invoked whenever a control transfer macro
(CXFRC) is executed and the exit point named CMXF is active.
Exit point CMXF is contained in CSECT CCNUCL. Exit point CMXF contains
different parameters depending on the CXFRC ECB= parameter.
UCCCMXF allows user information to be passed from a parent to a child
ECB. It is independent of macro servicing user exits.
General Conditions at Entry
The registers at entry to UCCCMXF are:
- R2
- Pointer to a 4-byte user data field where this routine can store data to
be passed to the child ECB. R2 equals 0 if CXFRC was unable to obtain
storage because of a low core condition.
- R5
- Set to 1 to show that ECB=DEFER was coded.
- R7
- Return address of CXFRC (CXFRTRN).
- R9
- If present, the address of the parent ECB. See Programming Considerations at Entry.
- R11-R15
- See User Exit Routines - Common Entry Conditions.
System Conditions at Entry
- System state
- Supervisor
- System mask
- Masked for I/O
- Protect key
- 0
- Address Space
- SVM or EVM.
General Conditions at Entry
The registers at entry to UCCCMXF are:
- R2
- Address of the new ECB.
- R5
- Set to 0 to show that ECB=IMMED was coded.
- R7
- Return address of CXFRC (CXFRTRN).
- R9
- If present, the address of the parent ECB. See Programming Considerations at Entry.
- R11-R15
- See User Exit Routines - Common Entry Conditions.
System Conditions at Entry
- System state
- Supervisor
- System mask
- Masked for I/O
- Protect key
- 0
- Address Space
- SVM.
Programming Considerations at Entry
- A parent ECB may or may not be present.
- See User Exit Routines - Common Entry Conditions.
- See User Exit Routines - Common Programming Considerations for other considerations.
Programming Considerations on Return
See User Exit Routines - Common Return Conditions.
General Conditions on Return
See User Exit Routines - Common Return Conditions.