COBOL-TRIGGER XFD directive

This XFD directive indicates that a COBOL trigger is to be executed.

Note: This XFD directive must come immediately before the file descriptor of the file for which the trigger is defined. It uses the standard XFD directive syntax.

Syntax

XFD COBOL-TRIGGER=program-name

Restriction: program-name must be a native COBOL executable file, such as an .int or .gnt file.

The following three parameters are passed to the COBOL program:

01  OPCODE.
  88  READ-BEFORE       VALUE "r".
  88  READ-AFTER        VALUE "R".
  88  WRITE-BEFORE      VALUE "w".
  88  WRITE-AFTER       VALUE "W".
  88  REWRITE-BEFORE    VALUE "u".
  88  REWRITE-AFTER     VALUE "U".
  88  DELETE-BEFORE     VALUE "d".
  88  DELETE-AFTER      VALUE "D".

01  FILE-RECORD         PIC X(MAX-RECORD-SIZE).

01  ERROR-CODE          PIC 99.

In cases in which the record size is known, the actual record is passed [READ-AFTER (all), WRITE-BEFORE, WRITE-AFTER, REWRITE-BEFORE, REWRITE-AFTER].

In cases in which the record size is not known, the maximum record size is passed [READ-BEFORE (all), DELETE-BEFORE, DELETE-AFTER].

The contents of this field are identical to the record area given to the file operation. The BEFORE images have the value before the file operation, and the AFTER images have the value after the file operation.

Use the ERROR-CODE parameter to signal that an error occurred:

If you set this parameter in a BEFORE trigger, the file operation does not execute
If you set this parameter in an AFTER trigger, the run time system treats the file operation as an error, though in fact the file operation did execute. This means that, for sequential access (next or previous), the file position has changed and a subsequent next or previous act as if the prior file operation succeeded

Also, if you set an error in the REWRITE-AFTER or DELETE-AFTER, the record does not return to its prior state — the record is modified or deleted in the database.

Please note that if the COBOL program cannot be called (for any reason), it is treated as having succeeded.