### 10.11.2 Referencing OmniHelp topic IDs from an application

To specify OmniHelp topic IDs to the browser, an application would make an exec file call with a file parameter that looks like one of the following:

_myproj.htm#file.htm | to get to a specific HTML file in myproj
_myproj.htm#IDH_contextID | to get to the file containing IDH_contextID

where myproj is a concatenation of the values specified in configuration section [OmniHelpOptions] for keywords OHProjFilePrefix, ProjectName, and OHProjFileSuffix (the underscore is the default value for OHProjFilePrefix). See §10.3 Setting up an OmniHelp project.

The second form (using IDH_contextID) is preferable, because it works even if the topic file name changes. Also, the second form provides a way for a WinHelp system to link to a specific topic in an OmniHelp system. The WinHelp project would not have to be recompiled if file names changed in the OmniHelp project.

| 10.11.1 Specifying alias prefixes for OmniHelp CSH calls |  | 10.11.3 Using redirect pages for OmniHelp CSH calls |