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XtDisplayInitialize(3)		  XT FUNCTIONS		  XtDisplayInitialize(3)

NAME
     XtDisplayInitialize,  XtOpenDisplay, XtDatabase, XtScreenDatabase, XtClose-
     Display - initialize, open, or close a display

SYNTAX
     #include <X11/Intrinsic.h>

     void XtDisplayInitialize(XtAppContext app_context, Display *display,  const
	    char  *application_name, const char *application_class, XrmOptionDe-
	    scRec *options, Cardinal num_options, int *argc, char **argv);

     Display   *XtOpenDisplay(XtAppContext   app_context,   const   char   *dis-
	    play_string,  const  char  *application_name,  const  char *applica-
	    tion_class, XrmOptionDescRec  *options,  Cardinal  num_options,  int
	    *argc, char **argv);

     void XtCloseDisplay(Display *display);

     XrmDatabase XtDatabase(Display *display);

     XrmDatabase XtScreenDatabase(Screen* screen);

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-spe-
	       cific  resources.   The options argument is passed as a parameter
	       to XrmParseCommand.  For further information, see Xlib -  C  Lan-
	       guage X Interface.

     screen    Specifies the screen whose resource database is to be returned.

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,  XtDisplay-
     Initialize  calls	the Xlib XSynchronize function to put Xlib into synchro-
     nous 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 applica-
     tion  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.

     The  XtScreenDatabase  function  returns the fully merged resource database
     associated with the specified screen.  If the screen does not belong  to  a
     Display initialized by XtDisplayInitialize, the results are undefined.

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

X Version 11			   libXt 1.3.1		  XtDisplayInitialize(3)

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