XtDisplayInitialize(3Xt)             SysV             XtDisplayInitialize(3Xt)



NAME
     XtDisplayInitialize, XtOpenDisplay, XtDatabase, XtCloseDisplay -
     initialize, open, or close a display

SYNTAX
     void XtToolkitInitialize()

     void XtDisplayInitialize(app_context, display, application_name,
     application_class,
                            options, num_options, argc, argv)
           XtAppContext app_context;
           Display *display;
           String application_name;
           String application_class;
           XrmOptionDescRec *options;
           Cardinal num_options;
           Cardinal *argc;
           String *argv;

     Display *XtOpenDisplay(app_context, display_string, application_name,
     application_class,
                            options, num_options, argc, argv)
            XtAppContext app_context;
            String display_string;
            String application_name;
            String application_class;
            XrmOptionDescRec *options;
            Cardinal num_options;
            Cardinal *argc;
            String *argv;

     void XtCloseDisplay(display)
           Display *display;

     XrmDatabase XtDatabase(display)
           Display *display;

ARGUMENTS
     argc      Specifies a pointer to the number of command line parameters.

     argv      Specifies the command line parameters.

     app_context
               Specifies the application context.

     application_class
               Specifies the class name of this application, which usually is
               the generic name for all instances of this application.

     application_name
               Specifies the name of the application instance.

     display   Specifies the display.  Note that a display can be in at most
               one application context.

     num_options
               Specifies the number of entries in the options list.

     options   Specifies how to parse the command line for any application-
               specific resources.  The options argument is passed as a
               parameter to XrmParseCommand.  For further information, see

               Xlib - C Language X Interface.

DESCRIPTION
     The XtDisplayInitialize function builds the resource database, calls the
     Xlib XrmParseCommand function to parse the command line, and performs
     other per display initialization.  After XrmParseCommand has been called,
     argc and argv contain only those parameters that were not in the standard
     option table or in the table specified by the options argument.  If the
     modified argc is not zero, most applications simply print out the
     modified argv along with a message listing the allowable options.  On
     UNIX-based systems, the application name is usually the final component
     of argv[0].  If the synchronize resource is True for the specified
     application, XtDisplayInitialize calls the Xlib XSynchronize function to
     put Xlib into synchronous mode for this display connection.  If the
     reverseVideo resource is True, the Intrinsics exchange
     XtDefaultForeground and XtDefaultBackground for widgets created on this
     display.  (See Section 9.6.1).

     The XtOpenDisplay function calls XOpenDisplay the specified display name.
     If display_string is NULL, XtOpenDisplay uses the current value of the
     -display option specified in argv and if no display is specified in argv,
     uses the user's default display (on UNIX-based systems, this is the value
     of the DISPLAY environment variable).

     If this succeeds, it then calls XtDisplayInitialize and pass it the
     opened display and the value of the -name option specified in argv as the
     application name.  If no name option is specified, it uses the
     application name passed to XtOpenDisplay.  If the application name is
     NULL, it uses the last component of argv[0].  XtOpenDisplay returns the
     newly opened display or NULL if it failed.

     XtOpenDisplay is provided as a convenience to the application programmer.

     The XtCloseDisplay function closes the specified display as soon as it is
     safe to do so.  If called from within an event dispatch (for example, a
     callback procedure), XtCloseDisplay does not close the display until the
     dispatch is complete.  Note that applications need only call
     XtCloseDisplay if they are to continue executing after closing the
     display; otherwise, they should call XtDestroyApplicationContext or just
     exit.

     The XtDatabase function returns the fully merged resource database that
     was built by XtDisplayInitialize associated with the display that was
     passed in.  If this display has not been initialized by
     XtDisplayInitialize, the results are not defined.

SEE ALSO
     XtAppCreateShell(3Xt), XtCreateApplicationContext(3Xt)
     X Toolkit Intrinsics - C Language Interface
     Xlib - C Language X Interface