Test by compiling your own version rather than trusting a repository. Also, you may try a win32 version in wine if you are not familiar with compiling software with libraries.

Gog.com supports DOS games on linux, an especially good option for those who are too busy or unable to troubleshoot linux systems. However, I am not aware of DOS games which require multiple monitors to run properly.

It's a problem with SDL of which the SDL guys are aware but won't do anything to fix... Dual monitor setups are not their big thing... Nor is SDL 1.2x which they don't want to actively develop anymore

If someone wants to walk me through the compilation steps -- I'm not a developer -- I'll give that a try. Meanwhile I downloaded the latest Win32 version from Sourceforge and installed it under Wine. The Win32 version never touches the secondary display. Fullscreen appears only on my primary display, and switching back to windowed mode leaves me with my original setup.

(However, the switch back to windowed mode leaves the contents of the DOSBox window black; can't see anything. But that's an issue for another day.)

It occurs to me I should have included the contents of dosbox.conf.

1[sdl]
2fullscreen=false
3fulldouble=false
4fullresolution=original
5#windowresolution=original
6windowresolution=1024x768
7output=opengl
8autolock=true
9sensitivity=100
10waitonerror=true
11priority=higher,normal
12mapperfile=mapper-0.74.map
13usescancodes=true
14
15[dosbox]
16language=
17machine=svga_s3
18captures=capture
19memsize=16
20
21[render]
22frameskip=0
23aspect=false
24scaler=normal2x

The issue with black in the Dosbox under wine is probably solved by using another output.

Thanks, Dominus. I'll give that a try, but I only tried it because truth5678 suggested it.

Speaking of which, I'm unclear what the test is intended to show -- that the bug doesn't exist in the Windows version, or only that Wine doesn't expose my dual monitors to DOSBox?

When I get home I'll also try playing around with other outputs to see if that gets around the original problem (which, sounds like it'll never be getting fixed).

BTW, I'm not trying to run DOSBox in dual monitor mode; I'd just be happy if DOSBox left my settings alone.

Does dosbox (linux version) work in windowed mode? If so, is this just a full screen issue where running multiple monitors(*)? Have you set scaler=none where running all tests?

SDL1 applications (like dosbox) do not support a multiple monitor setup in linux. My guess is that SDL1 is receiving the screen resolution from its X11 driver and that resolution is the total across both monitors. I also assume that you exported the SDL parameter "SDL_VIDEO_FULLSCREEN_DISPLAY=0", although that is not certain to confine the dosbox fullscreen window to a single monitor. In any case, SDL2 should detect the screen resolution for each of the different monitors (there is a SDL2 patch in development) and avoid the issue.

Here's another SDL (SDL1) patch to test: http://blog.pdark.de/2011/12/04/forcing-sdl-t … in-window-size/.

Apparently, wine is multi-monitor aware. If another output mode fixes the other issue where running dosbox in wine, then that is another option.

* http://trac.wildfiregames.com/ticket/1916?cve … n=0&cnum_hist=5