Selector adjuncts on input

GDDM V3R2 Base Application Programming Guide

Selector adjuncts on input

GDDM V3R2 Base Application Programming Guide
SC33-0867-01

Selector adjuncts are used on input, as well as output. When you execute an MSGET call, GDDM puts a code into the adjunct to indicate whether the field has been modified.

You may well find that input codes are the most useful aspect of adjuncts. They provide a simple means of discovering which fields have been changed by the end user. Without them, your program might have to store the old values of all the updatable fields, and compare them with the new values in the ADS after the MSGET.

The code indicates the state of the field as it exists on the current page, as follows:

blank

The field has no value. Either it has not had any data in it since the start of execution, or your program has emptied it and no data has been put into it since. You empty a field by clearing it to blanks or nulls, setting its selector adjunct to " ", and executing a write-type MSPUT call.

1

The field has a new value set by the end user. Except when the preceding MSPUT was a reject type, it indicates that the field was updated during the last ASREAD (or MSREAD). The precise meaning in the reject case is explained in "Effect of reject operation" in topic 16.3.1.

2

Not used on input.

3

The field has an old value. In other words, it contains a value that was put into it either by the application program, or by the end user during an ASREAD (or MSREAD) other than the last one.

Subtopics:

16.3.1 Effect of reject operation

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