3. Online Help

By default when you start GPS, the working area contains a welcome page giving a few starting points in the online help.

Online help for the GNAT tools is available from the Help menu item. GPS launches an external html browser to view these pages. (See The Preferences Dialog on how to configure this under Unix. Under Windows systems, the default HTML browser is used.)

3.1. The Help Menu

The Help menu item provides the following entries:

Welcome
Open the GPS Welcome page.
Contents
Open a special HTML file that contains links for all the documentation files currently registered in GPS, Adding New Help Files.
GPS
Submenu containing GPS documentation items.
GNAT Runtime
Submenu referencing all GNAT run-time files available, and a direct access to the corresponding specs containing embedded documentation.
Python extensions
Gives access to the GPS API available via python.
About

Display a dialog giving information about the versions of GPS and GNAT used:

_images/about.jpg

This menu contains a number of additional entries, depending on what documentation packages were installed on your system. See the next section to see how to add new help files.

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 Adding documentation.