The IXF Exit indicator combination is used for handling cross-field or whole item (row) data validation. The tablesONLINE/CICS program calls an exit program with these indicators before taking any action which outputs that item (row) data, that is, before any Update or New operation. This does not happen before Delete, which does not output the item, nor before Move which does not alter fields. The actual output operation is attempted only if cross-field validation succeeds. The IXF user exit is also invoked when the ENTER or the EXECUTE keys are pressed. This allows a user to validate all the field relationships by pressing <Enter>.
For the application developer, the IXF exit is one of the most powerful and convenient tools tablesONLINE/CICS provides. It is called after all field-level validations have run, but before the table updating action is taken, so it provides a central location for a variety of data-control functions. See Sample exit program for a variety of IXF examples.
tablesONLINE/CICS’s next action on a successful return from the IXF exit can vary. If the terminal user is attempting to operate on the item, then the next action will be an exit program call with indicators IUB, INB, or IMB. If the terminal user has just hit <Enter> to get cross-field validation without attempting any further action, then the next action tablesONLINE/CICS takes will be to return control to the user.
A BYPASS-ACTION-IND value of Y returned from an IXF exit prevents any action which would move the user off the current item. The user can update the row currently displayed but operations such as getting the next or previous row will always fail. This is useful for data integrity purposes. It is used, for example, in many of the tablesONLINE/CICS utility programs.
Here are possible values for the indicator and their associated meanings:
- Y—Data valid but moving off the row is forbidden
- E—Bad data
- W, I, or space—Good data