SpmiDdsAddCx Subroutine

Purpose

Adds a volatile context to the contexts defined by an application.

Library

SPMI Library (libSpmi.a)

Syntax

#include sys/Spmidef.h

char *SpmiDdsAddCx(Ix, Path, Descr, Asnno)
ushort Ix;
char *Path, *Descr;
int Asnno;

Description

The SpmiDdsAddCx subroutine uses the shared memory area to inform the SPMI that a context is available to be added to the context hierarchy, moves a copy of the context to shared memory, and allocates memory for the data area.

This subroutine is part of the server option of the Performance Aide for AIX® licensed product and is also included in the Performance Toolbox for AIX licensed product.

Parameters

Ix

Specifies the element number of the added context in the table of dynamic contexts. No context can be added if the table of dynamic contexts has not been defined in the SpmiDdsInit subroutine call. The first element of the table is element number 0.

Path

Specifies the full path name of the context to be added. If the context is not at the top-level, the parent context must already exist.

Descr

Provides the description of the context to be added as it will be presented to data consumers.

Asnno

Specifies the ASN.1 number to be assigned to the new context. All subcontexts on the same level as the new context must have unique ASN.1 numbers. Typically, each time the SpmiDdsAddCx subroutine adds a subcontext to the same parent context, the Asnno parameter is incremented. See Making Dynamic Data-Supplier Statistics Unique for more information about ASN.1 numbers.

Return Values

If successful, the SpmiDdsAddCx subroutine returns the address of the shared memory data area. If an error occurs, an error text is placed in the external SpmiErrmsg character array, and the subroutine returns a NULL value.

Error Codes

All SPMI subroutines use external variables to provide error information. To access these variables, an application program must define the following external variables:

• extern char SpmiErrmsg[];
• extern int SpmiErrno;

If the subroutine returns without an error, the SpmiErrno variable is set to 0 and the SpmiErrmsg character array is empty. If an error is detected, the SpmiErrno variable returns an error code, as defined in the sys/Spmidef.h file, and the SpmiErrmsg variable contains text, in English, explaining the cause of the error. See the List of SPMI Error Codes for more information.

Files