Re: [dwm] dwm and dualhead

From: Donald Chai <>
Date: Wed, 10 Dec 2008 19:23:15 -0800

On Dec 10, 2008, at 9:05 AM, Johannes Wegener wrote:

> is there anybody who has experience with dwm and dualhead setups? I
> tried to use dwm with a xrandr dualhead but it seemed quite useless
> becouse I
> could just drag floating windows into the second screen. Xinerama
> seems
> no more supported by xorg 7.4 and the intel driver.

I think people on this have lately been confusing "dualhead" with
"Xinerama". Someone asked about this earlier, and he just wanted to
clone screens. In any case, suppose we have two 1024x768 monitors, we
can use them in two ways:

- Two X displays, :0.0 and :0.1, each 1024x768
- This is sometimes called "Zaphod" mode.
- This mode sucks because you can't move windows from one screen to
the other.
- This mode is not supported by the intel driver.

- One merged display, :0.0 which is 2048x768 or 1024x1536 (your choice)
- If I understand correctly, this is Xinerama or mergedFB or TwinView
- This requires help from the window manager.
- Xrandr lets you switch between 2048x768 and 1024x1536 without
restarting X. It's fantastic.

You can compile dwm without Xinerama support (#undef XINERAMA) and
use Xorg with MODE 2. You end up with one giant display. If you
compile with -DXINERAMA, you have what you've described, where the
second screen is used for floating windows. "Xinerama support" just
means that dwm knows that the giant display consists of two screens,
and can avoid using dead space if the screens are different sizes.

When people say that xorg is dropping Xinerama support, I believe
it's the Xinerama implementation that's being dropped, not the API or
wire protocol. XineramaQueryScreens() works correctly on my netbook
with xorg 7.3 and intel driver.

With that out of the way, I'd suggest you look at dwm-gtx. I tried
it on my Acer Aspire One (with intel 945), and it worked well. The
difference between dwm-gtx and "awesome" (besides code bloat) is that
"awesome" manages tags for each screen independently. If I press
MOD-1 in "awesome", it switches the tag on the current screen. In
dwm-gtx, it switches both screens.
Received on Thu Dec 11 2008 - 03:23:15 UTC

This archive was generated by hypermail 2.2.0 : Thu Dec 11 2008 - 03:24:04 UTC