+.B \-m, \-\-multiscreen
+Output geometry information about the individual monitors of a
+(possibly) multihead display, rather than the overall size of the root
+window. This sets
+.B XNSCR
+to the number of monitors, and
+.BI XSCR n _X \fR,
+.BI XSCR n _Y \fR,
+.BI XSCR n _WIDTH \fR,
+and
+.BI XSCR n _HEIGHT \fR
+to the
+.IR x -
+and
+.IR y -coordinates
+of the pixel shown in the top-left of monitor
+.I n
+(starting from zero), and the width and height of monitor
+.I n
+in pixels. The monitors will be sorted in order of increasing
+.IR y -coordinate
+(i.e., top to bottom), with monitors with equal
+.IR y -coordinates
+sorted in order of increasing
+.IR x -coordinate
+(i.e., left to right). Usually, then, the first monitor will be at
+(0, 0).
+.IP
+This requires that support libraries for the X RANDR extension were
+available when
+.B xscsize
+was compiled, and that the display actually implements at least version
+1.2 of the RANDR extension. If not,
+.B xscsize
+will still accept the
+.B \-m
+option, and produce appropriately formatted output, but will assume that
+there is exactly one monitor, and that it shows the entire root window.
+.TP 5