DMXGetScreenCount - determine number of back-end screens


   #include <X11/extensions/dmxext.h>

   Bool DMXGetScreenCount(Display *dpy,
                          int *screen_count);


   DMXGetScreenCount()  returns  the  number  of  back-end  screens that a
   Xdmx(1) server controls.  Since a DMX screen usually fills all  of  the
   available  area  on  a  back-end  server, there is usually a one-to-one
   correspondence between DMX screens and backend servers.  However, it is
   also possible for a DMX screen to cover only part of the available area
   on a back-end server, and for more  than  one  DMX  screens  to  occupy
   different parts of the visible area on the same back-end server.

   A DMX screen may be managed as a regular X screen in the Xdmx(1) server
   or may be joined with other DMX screens using Xinerama.


   DMXGetScreenCount() sets screen_count and returns True unless there  is
   a protocol error.


   If  Xinerama  is  active,  only one logical screen will be available to
   clients of the Xdmx(1) server.   However,  this  call  will  accurately
   reflect  the  number  of  composite  back-end  screens that the Xdmx(1)
   server is using.


   DMXGetScreenAttributes(3),    DMXChangeScreensAttributes(3),    DMX(3),


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