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From: Barry Kelly <bkelly DOT ie AT gmail DOT com>
To: cygwin AT cygwin DOT com
Subject: Re: DOS programs under "screen"
Date: Tue, 21 Apr 2009 19:10:54 +0100
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Andrew Schulman wrote:

> > In general, non-cygwin programs can't be run reliably inside of an
> > application that uses cygwin PTYs, including xterm, rxvt, and screen.
>=20
> Maybe someone knows a solution to this, but I don't.  Although I maintain=
 screen
> for Cygwin, I know almost nothing of the details of how terminals work.  =
I could
> imagine some kind of a DOS-to-Unix terminal wrapper program, but I've nev=
er seen
> one and have no idea how it would work.

Windows implements console mode as a client-server protocol between the
executable (ntvdm.exe for DOS apps) and winsrv.dll (hosted in
csrss.exe), but the protocol isn't easily hookable. I guess one would
have to hijack the console APIs, perhaps by stepping into the
application using debugging APIs and overwriting the DLL imports, but it
would be pretty painful.

I don't know how DOS programs that use graphics modes (in fullscreen)
are implemented, though these must be rare now given that Vista no
longer has a full-screen mode.

-- Barry

--=20
http://barrkel.blogspot.com/

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