xfree86 man page for dmxgetscreencount

DMXGetScreenCount(3X)													     DMXGetScreenCount(3X)

NAME
       DMXGetScreenCount - determine number of back-end screens

SYNOPSIS
       #include <X11/extensions/dmxext.h>

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

DESCRIPTION
       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.

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

NOTES
       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.

SEE ALSO
       DMXGetScreenAttribtues(3X), DMXChangeScreenAttributes(3X), DMX(3X), Xdmx(1)

XFree86 							   Version 4.7.0					     DMXGetScreenCount(3X)