Types of Indicators

There are two types of indicators:

Option indicators pass information from a program to the system. For example, they can control which fields in a record can be displayed.

Response indicators pass information from the system to an application when an input request finishes. For example, they can be used to inform the program which function keys were pressed by the workstation user.

To use indicators, the display, ICF, and printer files must be defined as an externally described file. The data description specification (DDS) for the externally described display file must contain a one-character INDICATOR field for each indicator. Indicators are either in the records read or written by the program (the indicators are in the file buffer) or in a separate indicator area.