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DMXGetWindowAttributes(3)  Library Functions Manual  DMXGetWindowAttributes(3)

       DMXGetWindowAttributes -	determine back-end window attributes

       #include	<X11/extensions/dmxext.h>

       Bool DMXGetWindowAttributes(Display *dpy,
				   Window window,
				   int *screen_count,
				   int available_count,
				   DMXWindowAttributes *attr);

       When  calling  DMXGetWindowAttributes(),	window specifies the window ID
       of a window on the Xdmx(1) server  and  available_count	specifies  the
       length of attr.

       The  number  of	screens	for which information is available will	be re-
       turned in screen_count and information about those screen will  be  re-
       turned in attr.	If screen_count	is less	than available_count, then in-
       formation for all of the	screens	will be	returned.  Otherwise, informa-
       tion for	the first available_count screens will be returned.

       The DMXWindowAttributes structure is:

       typedef struct {
	   int		screen;
	   Window	window;
	   XRectangle	pos, vis;
       } DMXWindowAttributes;

       For  each  back-end  X  server  that displays a portion of window, this
       structure contains the physical screen  containing  that	 portion,  the
       window  ID  on the back-end X server of the window containing that por-
       tion, the position and dimensions of the	window on the  back-end	 (pos,
       in screen coordinates), and the visible area of the window on the back-
       end (vis, in window-relative coordinates	-- all zeros if	the window  is
       not visible on the backend).

       To   obtain   more  information	about  the  physical  screen  use  the
       DMXGetScreenAttributes(3) call.

       Note that DMX allows multiple back-end windows to overlap in their view
       of  the DMX logical window.  Further, a logical window does not have to
       be completely covered by	back-end windows -- there may be gaps.

       As an example, consider	a  500x500  window  that  spans	 the  top  two
       1024x768	 back-end  displays  (A	and B) of a 2048x1536 DMX display com-
       posed of	4 1024x768 back-end displays arranged in a cube:

	   A B
	   C D

       In this case, the DMXGetWindowAttributes	call would return the  follow-
       ing information for the 500x500 window:

       display A: 500x500 window at 1024-250,0 (relative to back end)
		  with 250x500 visible at 0,0 (relative	to window origin)

       display B: 500x500 window at -250,0 (relative to	back end)
		  with 250x500 visible at 250,0	(relative to window origin)

       display C: 500x500 window at 1024-250,-768 with 0x0 visible at 0,0

       display D: 500x500 window at -250,-768 with 0x0 visible at 0,0

       DMXGetWindowAttributes()	returns	True unless there is a protocol	error.

       DMXGetWindowAttributes()	can generate BadWindow and BadAlloc errors.

       Because this call transports a great deal of information	over the wire,
       please call DMXGetScreenCount(3)	first, and make	sure  attr  is	suffi-
       ciently large.

       On  a  particular  back-end  server, it is possible that	the associated
       window has not yet been mapped because the XMapWindow(3)	call that will
       eventually  map the window had been buffered by Xlib's normal buffering
       system.	To avoid this race condition, please  call  DMXSync(3)	before
       communicating directly with the back-end	X server.

       DMXGetScreenCount(3),  DMXSync(3),  DMXGetScreenAttributes(3),  DMX(3),

X Version 11			 libdmx	1.1.4	     DMXGetWindowAttributes(3)


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