IOHALT macro - is type 2, gets IOSUCB lock.
Calls module IGC0003C.
Note: This SVC can be used in two ways. The first way (which is used
by the IOHALT macro) is used by setting the low order bit of R1 to
1; the second way is used by setting the low order bit of R1 to 0.
GTF data for the first way (low-order bit of R1 is 1) is:
- R15
- No applicable data.
- R0
- UCB address (common segment), a fullword pointer; or address of
a UCBCOPY. (See z/OS MVS Programming: Assembler Services Reference IAR-XCT for
more information.)
- R1
- Contents:
- Bytes
- Contents
- 0-1
- If byte 1 of R1 is X'81' then R0 contains the offset
from the IOB to the virtual CCW that corresponds to the central CCW
to be modified to a NOP.
- 2
- Ignored
- 3
- Input Option
- = "01"
- use IOS HALT I/O subroutine.
- = "81"
- use EXCP CCW modify subroutine.
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|
|
|---|
| CUU |
dddd |
The device number associated with the device being halted. |
GTF data for the second way (low-order bit of R1 is 0) is:
- R15
- No applicable data.
- R0
- If byte 1 of R1 is X'81' then R0 contains the offset
from the IOB to the virtual CCW that corresponds to the central CCW
to be modified to a NOP.
- R1
- Contents:
- Bytes
- Contents
- 0
- Ignored
- 1
- Input Option
- = "00"
- use IOS HALT I/O subroutine.
- = "80"
- use EXCP CCW modify subroutine.
- 2-3
- Address of the UCB or UCBCOPY associated with the HALT request.
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|
|
|---|
| CUU |
dddd |
The device number associated with the device being halted. |