Class
Applications

Purpose
Trap program errors

Syntax
ON ERROR [<command>]

See Also
ON ESCAPE, ON KEY, RETRY, ERRNO(), ERROR(), MESSAGE(), SET ONERROR

Description
The ON ERROR command causes the specified <command> to be executed if an error is encountered in a program.  If ON ERROR is specified without a <command>, then the default Recital/4GL behavior will be restored.  By default, the Recital/4GL will stop execution at the error and an error.mem file will be created

<command>
The <command> can be any Recital/4GL command.  After an error is encountered, the ERROR() function will return the error number, and the MESSAGE () function will return the error message.  Specifying an ‘*’ as the command causes any errors to be ignored, so should be used with caution.  The RETRY command is often used with the ON ERROR trapping facility.

Example
procedure badfile
on error
set message to “File does not exist.”
return to master
on error do badfile
use patrons

Products
Recital Database Server, Recital Mirage Server, Recital Terminal Developer