At 04:52 PM 5/6/2005 +0200, Florian Xaver wrote:

As i understand, emm386 switches the pc into protected mode (so it needs
VCPI).Then... is it in V86 mode? So wouldn't it be possible to make a
better error handling. I mean, if a program hangs or so, that not the
computer hangs and that you can terminate the program and work
continuesly. So that the program work in ring 3?

It is in V86 mode, but doesn't help a great deal. Almost all DOS extended programs have their own address space and exception handling and EMM386 isn't in control. In "real" mode under the V86 monitor, a program which trashes any critical component of DOS or a driver before hitting an exception will crash the system. And if they don't do that, there remain many ways to lock up a machine that is unrecoverable.

Despite this, EMM386 can successfully recover from some application errors with an abort message and termination to DOS. It happens in my DOS sessions. Go into DEBUG and Assemble the protected instruction LSL AX,AX. You'll see it happen.

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