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XOpenDisplay(3)			XLIB FUNCTIONS		       XOpenDisplay(3)

       XOpenDisplay, XCloseDisplay - connect or	disconnect to X	server

       Display *XOpenDisplay(_Xconst char *display_name);

       int XCloseDisplay(Display *display);

       display	 Specifies the connection to the X server.

		 Specifies  the	 hardware  display  name, which	determines the
		 display and communications domain to be used.	 On  a	POSIX-
		 conformant  system,  if the display_name is NULL, it defaults
		 to the	value of the DISPLAY environment variable.

       The XOpenDisplay	function returns a Display structure  that  serves  as
       the  connection	to  the	X server and that contains all the information
       about that X server.  XOpenDisplay connects your	application to	the  X
       server  through TCP or DECnet communications protocols, or through some
       local inter-process communication protocol.  If the hostname is a  host
       machine	name and a single colon	(:) separates the hostname and display
       number, XOpenDisplay connects using TCP streams.	 If  the  hostname  is
       not specified, Xlib uses	whatever it believes is	the fastest transport.
       If the hostname is a host machine name and a double  colon  (::)	 sepa-
       rates the hostname and display number, XOpenDisplay connects using DEC-
       net.  A single X	server can support any or all of these transport mech-
       anisms  simultaneously.	 A  particular Xlib implementation can support
       many more of these transport mechanisms.

       If successful, XOpenDisplay returns a pointer to	a  Display  structure,
       which  is defined in If XOpenDisplay does not succeed, it returns NULL.
       After a successful call to XOpenDisplay,	all of the screens in the dis-
       play  can  be  used  by the client.  The	screen number specified	in the
       display_name argument is	returned by the	DefaultScreen  macro  (or  the
       XDefaultScreen  function).   You	can access elements of the Display and
       Screen structures only by using the information	macros	or  functions.
       For  information	about using macros and functions to obtain information
       from the	Display	structure, see section 2.2.1.

       The XCloseDisplay function closes the connection	to the	X  server  for
       the  display  specified	in the Display structure and destroys all win-
       dows, resource IDs Font,	Pixmap,	Colormap, Cursor,  and	GContext),  or
       other resources that the	client has created on this display, unless the
       close-down mode of the resource has been	 changed  (see	XSetCloseDown-
       Mode).	Therefore,  these  windows,  resource IDs, and other resources
       should never be referenced again	or an error will be generated.	Before
       exiting,	 you  should call XCloseDisplay	explicitly so that any pending
       errors are reported as XCloseDisplay performs a final XSync operation.

       XCloseDisplay can generate a BadGC error.

       AllPlanes(3), XFlush(3),	XSetCloseDownMode(3)
       Xlib - C	Language X Interface

X Version 11			 libX11	1.6.12		       XOpenDisplay(3)


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