HOLD-SUBSYSTEM

Put subsystem on hold

Component:	DSSM
Functional area:	Subsystem management
Domain:	SYSTEM-MANAGEMENT
Privileges:	OPERATING SUBSYSTEM-MANAGEMENT
Routing code:	R

Function

The HOLD-SUBSYSTEM command enables any required subsystem to be put on hold.
No new connection is permitted to the specified subsystem; the required resources (holder task, address space) remain available. In addition, the FORCED operand enables the system to wait for all the connected tasks to be disconnected or the subsystem to be put on hold immediately. Once the deinitialization phase is complete, the subsystem is on hold; this status can be canceled using the RESUME-SUBSYSTEM command.

The HOLD-SUBSYSTEM command is rejected if SUBSYSTEM-HOLD=*FORBIDDEN was specified when the subsystem was defined.

In order to ensure a high degree of parallelism and data integrity, time-consuming administration tasks are not performed under control of the calling task; instead, they are transferred to a DSSM task. As a rule, only the check of the requested function is carried out synchronously (i.e. contingent upon a wait state for the calling task). DSSM carries out the actual processing asynchronously and independent of the calling task.

Format

HOLD-SUBSYSTEM

SUBSYSTEM-NAME = <structured-name 1..8>

,VERSION = *STD / <product-version mandatory-man-corr> / <product-version without-man-corr> / *HIGHEST

,SUBSYSTEM-PARAMETER = *NONE / <c-string 1..254>

,FORCED = *NO / *YES

,SYNCHRONOUS = *NO / *YES

Operands

SUBSYSTEM-NAME = <structured-name 1..8>
Name of the subsystem to be put on hold.

VERSION = *STD / <product-version mandatory-man-corr> /
<product-version without-man-corr> / *HIGHEST
Specifies the version number.
If a version number is specified, the format specified here must be identical to the format used when the subsystem was defined (release and correction status mandatory or not allowed; see the description of the data type "product-version" in section "SDF syntax representation" in chapter "Volume 1: General Part").

VERSION = *STD
If there is only one loaded version of the subsystem, this version is selected. If there are several suitable versions, the version must be specified.

VERSION = *HIGHEST
Selects the highest version of the subsystem.

SUBSYSTEM-PARAMETER = *NONE / <c-string 1..254>
Specifies whether special parameters, which can be evaluated only by the specified subsystem, are to be processed.

FORCED =
Determines the mode and urgency of command processing.

FORCED = *NO
The system waits for all tasks connected to the subsystem to be disconnected. When a task releases its connection depends on the subsystem. A connection to a nonprivileged subsystem (e.g. EDT) is released as soon as the program terminates.
Processing and hence normal termination of all the tasks accessing this subsystem is allowed to take its normal course.

FORCED = *YES
The subsystem is halted immediately.
In the case of a privileged subsystem, this can lead to system dumps of the tasks which are still connected; in the case of a nonprivileged subsystem, this can lead to user dumps or to the execution of the STXIT error handling routine which is offered by DSSM. Tasks that are connected to a nonprivileged subsystem can exit by means of the STXIT error handling routine which is offered by DSSM.

SYNCHRONOUS =
Enables synchronous or asynchronous processing to be selected.

SYNCHRONOUS = *NO
The command is to be processed asynchronously, i.e. there is no need to wait for it to execute before making another entry. Once the syntax of the command has been checked, the calling task is sent message ESM0216. No error messages relating to execution of the command will be output.

SYNCHRONOUS = *YES
The command must first be executed before another entry can be made. Accompanying error messages are output. 

Return codes

(SC2)	SC1	Maincode	Meaning
	0	CMD0001	No error
1	0	CMD0001	No action necessary
	1	ESM0414	Syntax error: invalid version specified
	32	ESM0224	Command not processed
	32	ESM0228	Command terminated abnormally