IFDSET (HLI function)

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

Summary

Description
The IFDSET call (DELETE SET) deletes the records that are in a found set from a file or group.
Thread type
multiple cursor IFSTRT, single cursor IFSTRT
IFCALL function number
21

Syntax

IFDSET(RETCODE,SET_QUAL)

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.
SET_QUAL

[I,c,r] The set qualifier is available only for use with a multiple cursor IFSTRT thread, and it is required for specifying the record set or list that will be used to delete records from a file or group. Specify a character string using either one of the following formats:

{IN label | ON [LIST] listname}

where:

label is the name of a saved IFFIND, IFFNDX, IFFWOL, or IFFAC compilation from the previously compiled call, which established the record set.

listname specifies the name of a list.

Note: The set qualifier is not a valid parameter for use with a single cursor IFSTRT thread.

Usage notes

Use the IFDSET call to delete records from a file or group.

Note: You cannot use IFDSET with a sorted record set.

When FOPT=X'10' and the date/time stamp feature is installed, the IFDSET function is supported for DTS files.

There is another call, IFDREC, that also deletes records from a file or group. IFDSET executes faster than IFDREC. However, with IFDSET the file storage space that is occupied by the deleted set of records is not reclaimed and the record numbers are not reused.

The IFDSET call is valid on all types of IFSTRT threads. You must specify the found set for records that are to be deleted on a multiple cursor IFSTRT thread. On a single cursor IFSTRT thread, IFDSET deletes records from the current set.

Coding example (COBOL)

WORKING-STORAGE SECTION. 01 ARGS-FOR-CALL. 05 RETCODE PIC 9(5) COMP SYNC. 05 DEL-SET PIC X(10) VALUE "IN PREVFD;". . . . PROCEDURE DIVISION. . . . CALL "IFDSET" USING RETCODE, DEL-SET.

Note: The example above illustrates the use of the set qualifier parameter (DEL-SET), which is available for use only with a multiple cursor IFSTRT thread.