MFXOPEN 

The REQUIRED Clause

General Format


*

Syntax Rules

  1. The REQUIRED clause is allowed only with input and update fields and with group items.
  2. This clause can be specified on a group screen item, in which case it applies to all suitable elementary items which are subordinate to that item.
  3. MF REQUIRED and EMPTY-CHECK are equivalent.

General Rules

  1. The REQUIRED clause takes effect during the execution of any ACCEPT statement that causes the screen item to be accepted provided the cursor enters the screen item at some time during the ACCEPT. Unless this clause is satisfied, terminator keystrokes are rejected and the cursor is repositioned to the beginning of the item.
  2. To satisfy this clause, alphanumeric screen items must contain at least one non-space, non-prompt character; numeric screen items must have a non-zero value.
  3. For update fields, the REQUIRED clause can be satisfied by initial data as well as by operator-keyed data.
  4. The REQUIRED clause cannot be effective if a function key is used to terminate an ACCEPT operation. (See your COBOL system documentation about user interfaces for details on configuration options.)
  5. An error message can be configured for display on the screen if the REQUIRED clause is not satisfied. (See your COBOL system documentation about user interfaces for details on configuration options.)