### 3.2 Adding New Help Files

GPS will search for the help files in the list of directories set in the environment variable `GPS_DOC_PATH` (a colon-separated list of directories on Unix systems, or semicolon-separated list of directories on Windows systems). In addition, the default directory `<prefix>/share/doc/gps/html` is also searched. If the file cannot be found in any of these directories, the corresponding menu item will be disabled.

The environment variable `GPS_DOC_PATH` can either be set by each user in his own environment, or can be set system-wide by modifying the small wrapper script `gps` itself on Unix systems.

It can also be set programmatically through the GPS shell or any of the scripting languages. This is done with

         GPS.add_doc_directory ("/home/foo")

The specific list of files shown in the menus is set by reading the index files in each of the directories in `GPS_DOC_PATH`. These index files must be called `gps_index.xml`.

The format of these index files is specified in see Adding documentation.