START/STOP options
Syntax
The START/STOP options of the STATUS macro are written as follows:
Syntax | Description |
---|---|
name | name: Symbol. Begin name in column 1. |
␢ | One or more blanks must precede STATUS. |
STATUS | |
␢ | One or more blanks must follow STATUS. |
START | |
STOP | |
,TCB=tcb addr | tcb addr: RX-type address or address in register (2) - (12), or 0. |
,SRB | ASID addr: RX-type address or address in register (2) - (12). |
,SRB, ASID=ASID addr | Note: ASID may only be specified with START. |
,RELATED=value | value: Any valid macro keyword specification. |
Parameters
The parameters are described as follows:
- START
- STOP
- Specifies that the task identified in the TCB parameter is to
be stopped (STOP) or started (START). If you omit the TCB parameter,
all subtasks of the originating task are stopped or started. Note: The STOP parameter does not ensure that the subtask is stopped when control returns to the issuer. A subtask can have a “stop deferred” condition that would cause that particular subtask to remain dispatchable until stops are no longer deferred. In an MP environment, it would be possible to have a task issue the STATUS macro with the STOP parameter and resume processing while the subtask (for which the STOP was issued) is redispatched to another processor.
- ,TCB=tcb addr
- ,SRB
- ,SRB,ASID=ASID addr
- Specifies the status of the stop/start function:
- TCB
- Specifies the address of a fullword on a fullword boundary containing
the address of the TCB that is to have its START/STOP count adjusted. Note: The TCB resides in storage below 16 megabytes.
- SRB
- Specifies that the STOP and START functions affect the dispatchability of system-level SRBs; all tasks in the address space except the caller's are also set or reset nondispatchable. For START, the ASID addr specifies the address of a halfword containing the address space identifier. If ASID is not specified, the action is taken against the caller's address space.
- ,RELATED=value
- Specifies information used to self-document macros by “relating” functions or services to corresponding functions or services. The format and contents of the information specified are at the discretion of the user and may be any valid coding values.
Return codes
When control returns to the caller, register 15 contains one of the following hexadecimal return codes:
Return Code | Meaning and Action |
---|---|
00 | Meaning: Processing completed successfully. Action: None required. |
04 | Meaning: Program error. START/STOP request
failed. The task you specified is not a subtask of the calling program's
task. Action: Ensure that the task you specify on the TCB parameter is a subtask of the calling program. |