in relation to this question, I'm using the xrandr command in osx to perform operations on my external monitors. Unfortunately it does not appear to be recognising external montitors at all:
Cobrakai$xrandr --verbose --screen 1
Invalid screen number 1 (display has 1)
Whereas it works fine for screen 0 (my native screen)
Cobrakai$xrandr --screen 0
xrandr: Failed to get size of gamma for output default
Screen 0: minimum 640 x 480, current 2304 x 1824, maximum 2304 x 1846
default connected 2304x1824+0+0 0mm x 0mm
1280x800 60.0 2.0
1152x720 60.0
1024x768 60.0
1024x640 60.0
800x600 60.0
800x500 60.0
640x480 60.0
720x480 60.0
1280x778 1.0
1280x1824 1.0
1280x1846 2.0
2304x1824 1.0*
2304x1846 2.0
Cobrakai$
Even when other applications can tell that there are many screens (per screenshot) - how do I get xrandr to recognise the additional screens?