Skip to main content


Specify the $ZDATE response to an invalid value.


[Miscellaneous]    ZDateNull=n

n is either 1 (true) or 0 (false). The default value is 0.


ZDateNull determines how a $ZDATE call responds when triggered by an invalid value. When this parameter is enabled, $ZDATE returns a null value. When this parameter is not enabled, it returns an error.

Changing This Parameter

On the Compatibility page of the Management Portal (System Administration > Configuration > Additional Settings > Compatibility), in the ZDateNull row, click Edit. Select ZDateNull to enable this setting.

Instead of using the Management Portal, you can change ZDateNull in the Config.Miscellanous class (as described in the class reference) or by editing the CPF in a text editor (as described in the Editing the Active CPF section of the “Introduction to the Configuration Parameter File” chapter in this book).

To change this parameter for a single process only (as opposed to instance-wide), use the ZDateNull() method of the %SYSTEM.Process class. See the class reference for details.