Primary monitor of dual setup

Russell Shaw rjshaw at
Tue Aug 19 16:12:51 PDT 2008

Steven J Newbury wrote:
> On Tue, 2008-08-19 at 17:34 +0200, Tomas Carnecky wrote:
>> Steven J Newbury wrote:
>>> On Tue, 2008-08-19 at 11:13 -0400, Alex Deucher wrote:
>>>> On Tue, Aug 19, 2008 at 12:35 AM, Russell Shaw <rjshaw at> wrote:
>>>>> Hi,
>>>>> I used xrandr to set up two monitors with one desktop stretched between them.
>>>>> The window manager taskbar (icewm) appears on the right-hand monitor.
>>>>> How do i make the left-hand monitor the primary one?
>>>> I'm not sure about icewm, but with gnome, you can just drag the panel
>>>> to whichever monitor you want it on.
>>> That really isn't a solution though.  It has to be done every time you
>>> expand the desktop AFAICT.
>>> The "right" solution has to be the ability to re-order (specify primary)
>>> outputs with xrandr.  This is the only thing I'm really unhappy with
>>> with respect to the xrandr monitor hotplug support.
>> Technically, AFAICS, there is no notion of 'primary' and 'secondary' 
>> outputs. All outputs are equal, and reported in the order in which the 
>> driver detects them. IMO the 'right' solution would be to configure 
>> these things (such as: where should the panel appear?) in the desktop 
>> (gnome/kde etc). Or have the gnome panel remember to which output is was 
>> dragged to.
> The problem is, up until xrandr, there has been an assumption by
> toolkits/desktops that there is a significance to the order.  Prior
> expanded desktop solutions such as the radeon driver's mergedfb and
> NVidia's proprietary TwinView support(ed) specifying the order, so it
> is/was a de-facto standard even if it wasn't ever intended to be so.

I found it's window-manager specific. This fixed it for icewm:

   # Primary screen for xinerama (taskbar, ...)
   # XineramaPrimaryScreen=0 # [0-63]

In newer video drivers (such as radeonhd), i think you could use in xorg.conf:

   Option "RROutputOrder" "list-of-outputs"

My radeon driver didn't have that option though.

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