Using the system programmer interface

GDDM V3R2 Base Application Programming Reference

Using the system programmer interface

GDDM V3R2 Base Application Programming Reference
SC33-0868-02

The system programmer interface is a special interface available to "system programming" types of applications. It is available only in reentrant form, and shares many features with the application-programmer reentrant interface. The reentrant interfaces are described in "GDDM programming interface" in topic 1.0.

In the simplest case, the system programmer interface merely provides a means of accessing a GDDM function by a function code (the Request Control Parameter, RCP) rather than by selecting an entry point. Assembler-language macros defining mnemonics for these function codes are provided.

Each call takes the form:

 CALL ADMASP (aab,rcp,component parameters,...)                         

where ADMASP is the defined system programmer interface entry point. ADMASP is a single entry point resolved by the GDDM interface modules that are link-edited with the application.

Note: The sample PL/I declarations do not include this entry point, because it can only be called using the system programmer interface. The PL/I application programmer using this call must, therefore, supply an entry-point declaration for the system programmer interface, as described in "The GDDM calls" in topic 3.0. For example:


     DECLARE ADMASP EXTERNAL ENTRY OPTIONS (ASM,INTER);

Parameters

aab (specified by user) (8-byte control block)
An Application Anchor Block, as described in "GDDM programming interface" in topic 1.0.

rcp (specified by user) (fullword integer)
The Request Control Parameter, a 4-byte, fullword-aligned function code defining the GDDM function to be called. The GDDM RCP code is given, for each GDDM call listed and described in "The GDDM calls" in GDDM Diagnosis book contains a table defining the RCP codes for all GDDM calls.

RCP codes are the function codes to be specified when invoking GDDM and GDDM-PGF by means of the system programmer interface (SPI). The codes are also set by GDDM in error records passed to user error exits, or produced in response to FSQERR calls.

Assembler-language tables ADMURCPB and ADMURCPO define RCP codes. Table ADMURCPB defines the RCP codes for GDDM only. ADMURCPO defines the RCP codes for both GDDM and GDDM-PGF. (On CMS these tables are in ADMLIB MACLIB; on MVS they are in the SADMSAM data set; and on VSE they are supplied as member type Z.)

The RCP codes are defined as symbolic Assembler-language EQUATE statements of mnemonics (QQxxxxxx) to numeric values. The "xxxxxx" of the mnemonic is the name of the GDDM or GDDM-PGF function; for example,

QQFSINIT EQU X'0C000001'

component parameters
The parameters for the function specified in the RCP. These are as described for the specific function being called.

Calls to the system programmer and reentrant interfaces can be mixed, provided that the same application anchor block is passed on each call.

Subtopics:

Notices | Terms of use | Support | Contact z/OS