XtDisplayInitialize(3Xt)    X Version 11(Release 3)    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.



10/89                                                                    Page 1

XtDisplayInitialize(3Xt)    X Version 11(Release 3)    XtDisplayInitialize(3Xt)


      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.





Page 2                                                                    10/89

XtDisplayInitialize(3Xt)    X Version 11(Release 3)    XtDisplayInitialize(3Xt)


      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













































10/89                                                                    Page 3