SPOST — Synchronize POST

Description

The SPOST macro is used in a cross memory post environment to ensure that all outstanding cross memory post requests to the current address space have completed. SPOST resolves a synchronization problem that arises when it becomes necessary to free an ECB that is a potential target for a cross memory post request. Before issuing SPOST, you must stop any new posts from being initiated.

For explanation of the parameters in a cross memory post request, see the POST macro.

Environment

These are the requirements for the caller:

Environmental factor	Requirement
Minimum authorization:	Supervisor state or PSW key 0-7 or APF authorized
Dispatchable unit mode:	Task
Cross memory mode:	PASN=HASN=SASN
AMODE:	24- or 31-bit
ASC mode:	Primary
Interrupt status:	Enabled for I/O and external interrupts
Locks:	No locks held
Control parameters:	None

Programming requirements

The caller must include the CVT mapping macro.

Restrictions

None.

Input register information

Before issuing the SPOST macro, the caller does not have to place any information into any register unless using it in register notation for a particular parameter or using it as a base register.

Output register information

When control returns to the caller, the GPRs contain:

Register: Contents
0-1: Used as work registers by the system
2-13: Unchanged
14-15: Used as work registers by the system

When control returns to the caller, the ARs contain:

Register: Contents
0-1: Used as work registers by the system
2-13: Unchanged
14-15: Used as work registers by the system

Performance implications

None.

Syntax

The SPOST macro is written as follows:

Syntax	Description

`name`	`name`: Symbol. Begin `name` in column 1.

␢	One or more blanks must precede SPOST.

SPOST

␢	One or more blanks must follow SPOST.

Note: SPOST contains no optional or required parameters.

ABEND codes

See z/OS MVS System Codes for an explanation and programmer responses for this code.

Return and reason codes

None.

Example

Execute the SPOST macro with a comment.

SPOST                     ,ISSUE SPOST