Help on help tells users how to use the Help System. Specifically, it describes such tasks as using hyperlinks, navigating topics, using the index, and printing help topics. Normally, help on help is supplied as an individual help volume named Help4Help.
The Help4Help volume and its source files are included in the Developer's Toolkit. You can use the default volume "as is," or modify it for your application's design.
If you are writing application-specific help, there are two ways to ensure that your application has help on help for its own help dialogs:
Rely on the desktop's help on help volume. For example, on workstations running the desktop, the standard Help4Help volume is installed.
Supply your own help on help volume. The HelpTag source files for the Help4Help volume are provided in the /usr/dt/dthelp/help4help/C directory. A control subdirectory contains HelpTag processing files. You run HelpTag in this directory to create the run-time help file. Graphics files used in the help on help volume are stored in the control/graphics subdirectory.
If you are writing standalone help, you are probably relying on the Helpview program already being installed and ready to use. If this is the case, you don't have to worry about help on help because Helpview accesses the standard Help4Help volume by default.
Each application that uses the Help System (including Helpview) has a helpOnHelpVolume resource that identifies a help volume to be accessed for help on help topics. For Helpview, this resource is set as follows:
If you provide your own help on help volume, be sure to give it a unique name so it doesn't conflict with another help on help volume that may be installed on the system.