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XOpenDisplay(3)			XLIB FUNCTIONS		       XOpenDisplay(3)

       XOpenDisplay, XCloseDisplay - connect or	disconnect to X	server

       Display *XOpenDisplay(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 <X11/Xlib.h>.  If XOpenDisplay does not succeed, it
       returns NULL.  After a successful call to XOpenDisplay, all of the
       screens in the display 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 (Window, Font, Pixmap, Colormap, Cursor, and GCon-
       text), or other resources that the client has created on	this display,
       unless the close-down mode of the resource has been changed (see	XSet-
       CloseDownMode).	Therefore, these windows, resource IDs,	and other re-
       sources 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 op-

       XCloseDisplay can generate a BadGC error.

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

X Version 11			 libX11	1.6.5		       XOpenDisplay(3)


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