IFEPRM (HLI function): Difference between revisions

From m204wiki
Jump to navigation Jump to search
(Created page with " ==Summary== <dl> <dt>Description</dt> <dd>The IFEPRM call (EXAMINE PARAMETER) returns the value of the specified Model 204 parameter. </dd> <dt>Thread type</dt> <dd>multiple...")
 
No edit summary
Line 1: Line 1:
The conventions used on this page are described in [[HLI: Function call list#Function call notation conventions|Function call notation conventions]].


==Summary==
==Summary==

Revision as of 22:01, 11 July 2016

The conventions used on this page are described in Function call notation conventions.

Summary

Description
The IFEPRM call (EXAMINE PARAMETER) returns the value of the specified Model 204 parameter.
Thread type
multiple cursor IFSTRT, single cursor IFSTRT
IFCALL function number
25

Syntax

IFEPRM(RETCODE,PARM_NAME,PARM_VALUE,FILE_SPEC)

Compile-only form
Not available
Execute-only form
Not available

Specify the parameters in the syntax order shown above.

Parameter Description
RETCODE [O,i,r] The Model 204 return code is the required first parameter. The code is a binary integer value.

If the IFEPRM call is unsuccessful, Model 204 returns an error code of 4 if an attempt was made to view a parameter that cannot be viewed.

PARM_NAME [I,c,r] The parameter name is a required input parameter that specifies the name of the Model 204 parameter whose value will be returned. Specify a character string, the keyword name of any Model 204 system, file, or user parameter.

Note: On a multiple cursor IFSTRT thread you may specify the file context for a Model 204 file parameter by using FILE_SPEC, described below.

PARM_VALUE [O,c,r] Value is a required output parameter that specifies the location of the output parameter for the return parameter value. Specify a character string variable. Model 204 returns the value as a character string or as a character representation of a numeric value, up to eleven characters in length.
FILE_SPEC [I,s,o] The file specification is an optional input parameter for use only with a multiple cursor IFSTRT thread; it specifies the name of the file for which the Model 204 file parameter will be returned. Specify the Model 204 file name as a short character string using the following format:

IN [FILE] filename

The specified file must be open on the thread, otherwise the call is unsuccessful and Model 204 returns a completion code equal to 4.

Usage notes

Use the IFEPRM call to examine or to retrieve a Model 204 parameter value.

The IFEPRM call is valid on all types of IFSTRT threads. IFEPRM can be used on a single cursor IFSTRT thread to access the current record number when it is executed following an IFGET call and specifies CURREC as the parameter name.

Alternatively, on a multiple cursor thread every cursor has a current record, so CURREC need not be specified and its use is illegal. You can use the IFRNUM call to get the current record from the specified cursor.

Note: The file context can change on a multiple cursor thread. If a Model 204 file parameter is specified for PARM_NAME and the file specification parameter (FILE_SPEC) is omitted, IFEPRM returns a value for the default file on the thread (that is, the last file opened).

Coding example (PL/1)

The IFEPRM call below sets the string variable INVAR to the value of the Model 204 system parameter LIBUFF:

CALL IFEPRM (RETCODE,'LIBUFF',INVAR);