The mainline exits have these register contents on entry:
- Register
- Contents
- 0
- Address of the exit parameter block (EXPB)
- 1
- Address of a parameter list
- 2–12
- Not applicable
- 13
- Address of register save area
- 14
- Return address
- 15
- Entry point address
The service exits have these register contents on entry:
- Register
- Contents
- 0
- Address of the exit parameter block (EXPB)
- 1
- Address of a parameter list
- 2–13
- Not applicable
- 14
- Return address
- 15
- Entry point address
The CKDS entry retrieval installation exit has these register contents
on entry:
- Register
- Contents
- 0
- Not applicable
- 1
- Address of a parameter list
- 2–12
- Not applicable
- 13
- Address of register save area
- 14
- Return address
- 15
- Entry point address
The conversion program,
single-record, read-write, and KGUP exits have these register
contents on entry:
- Register
- Contents
- 0
- Not applicable
- 1
- Address of a control block (CVXP, RWXP, or KGXP, depending on
the exit)
- 2–12
- Not applicable
- 13
- Address of register save area
- 14
- Return address
- 15
- Entry point address
The particular control blocks that are passed through register
0 or register 1 are described with each exit.