Common Desktop Environment: Help System Author's and Programmer's Guide

To Set the helpOnHelpVolume Resource

    Add a line to your application's application-defaults file like this:

App-class*helpOnHelpVolume:  volume

Where App-class is the application's class name and volume is the name of the help on help volume you want to access.

Or, within your application, set the helpOnHelpVolume resource for each help dialog you create.