XtDisplayInitialize(3Xt)                 XtDisplayInitialize(3Xt)



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

SYNOPSIS
     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;

DESCRIPTION
     The XtDisplayInitialize function builds the resource data-
     base, calls XrmParseCommand(3X) 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 0, most applications simply print out
     the modified argv along with a message listing the allowable
                      r
     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, XtDisplayIn-
     itialize calls XSynchronize(3X) to put Xlib into synchronous
     mode for this display connection.  If the reverseVideo
     resource is TRUE, the Intrinsics exchange XtDefaultFore-



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XtDisplayInitialize(3Xt)                 XtDisplayInitialize(3Xt)



     ground and
     XtDefaultBackground for widgets created on this display.
     (See Section 9.6.1 in X Toolkit Intrinsics - C Language In-
     terface).

     The XtOpenDisplay function calls XOpenDisplay with 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, XtOpenDisplay then calls
     XtDisplayInitialize and passes it the opened display and the
     value of the -name option specified in argv as the applica-
     tion name.  If no name option is specified, XtDisplayIni-
     tialize uses the application name passed to it.  If the ap-
     plication name is NULL, XtDisplayInitialize uses the last
     component of argv[0].  XtOpenDisplay returns the newly
     opened display or NULL if XtDisplayInitializer failed.

     XtOpenDisplay is provided as a convenience to the applica-
     tion 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; other-
     wise, 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.

   Arguments
     These functions accept the following 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



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XtDisplayInitialize(3Xt)                 XtDisplayInitialize(3Xt)



             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 argu-
             ment is passed as a parameter to
             XrmParseCommand.  For further information, see
             Xlib - C Language Interface.

SEE ALSO
     XtAppCreateShell(3Xt), XtCreateApplicationContext(3Xt)

     X Toolkit Intrinsics - C Language Interface

     Xlib - C Language Interface
































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