Xref: utzoo comp.os.msdos.misc:2082 comp.windows.ms:12647 comp.os.os2.misc:1371 Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!sun-barr!olivea!apple!netcomsv!resnicks From: resnicks@netcom.COM (Steve Resnick) Newsgroups: comp.os.msdos.misc,comp.windows.ms,comp.os.os2.misc Subject: Re: OS/2 2.0 is here! vs Windows 3.0 vs NeXT/MACH Message-ID: <1991May13.170635.5406@netcom.COM> Date: 13 May 91 17:06:35 GMT References: <1991May9.182102.29631@netcom.COM> <1991May10.204939.17701@herald.usask.ca> Sender: netnews@netcom.COM (USENET Administration) Organization: Netcom - Online Communication Services UNIX System {408 241-9760 guest} Lines: 41 In article <1991May10.204939.17701@herald.usask.ca> lowey@herald.usask.ca (Kevin Lowey) writes: >From article <1991May9.182102.29631@netcom.COM>, by resnicks@netcom.COM (Steve Resnick): > >> The DOS box runs in real mode which means there is not protection. If you >> crash the DOS box, it could very likely kill the rest of the machine. >> OS/2 2.0 shouldn't have this problem. > >I've been running OS/2 from 1.0. I've crashed the DOS box many times. >Most of those times, all I have to do is press - and I am back in my >OS/2 sessions. They still operated fine. > >The only exception to this is if the DOS program screws up the keyboard >interrupt so that the - doesn't get passed through to OS/2. > I have managed to get things like: An internal processing error was encountered which dumps things like registers and such and then says The system is stopped. If you really want to make OS/2 crash from the DOS box, you could enter protected mode and go and trash memory while running at PL0. I don't know of any DOS programs which enter protected mode via some "non-standard" meathod, and I assume that INT15 Func 89H is disabled, but I have never checked this. I would also assume that you can trash the interrupt vector table at 0:0 and kill the system too. This is a lot more likely since all you need to do is write to a NULL far pointer. memcpy(NULL,foo,0x3FF) should trash the entire table. Cheers! Steve -- ------------------------------------------------------------------------------- resnicks@netcom.com, steve@camphq, IFNA: 1:143/105.0, co moderator for comp.binaries.os2 Real life: Steve Resnick. Chief Software Architect, Process Scientific, Inc Flames, grammar and spelling errors >/dev/null The Asylum OS/2 BBS - (408)263-8017 12/2400,8,1 - Running Maximus CBCS 1.2 -------------------------------------------------------------------------------