The IF_ERROR command is a hybrid version of the normal IF command. It allows for the "error condition" inside a validation block to be checked.
For more information about the raising of the "error condition" inside a validation block refer to the ENDCHECK command.
An optional error message may be issued when the "error condition is raised".
Also See
Optional
IF_ERROR ----- MSGTXT ------- *NONE -------------------------->
message text
>-- MSGID -------- *NONE -------------------------->
message identifier
>-- MSGF --------- DC@M01 . *LIBL ----------------->
message file . library name
>-- MSGDTA ------- substitution variables ---------|
| expandable group expression |
-------- 20 max -------------