Comments on: David Weise http://www.math.columbia.edu/~woit/wordpress/?p=149 Tue, 24 Nov 2009 05:04:42 -0500 http://wordpress.org/?v=2.8.6 hourly 1 By: Anonymous http://www.math.columbia.edu/~woit/wordpress/?p=149&cpage=1#comment-2286 Anonymous Wed, 31 Dec 1969 19:00:00 +0000 http://www.math.columbia.edu/~woit/wordpress/?p=149#comment-2286 The real issue is the "mode switch", which was <a href="http://minix1.bio.umass.edu/faq/286mdfx2.html" rel="nofollow">nearly impossible</a> on the 286. IBM had no 386 to shoot at when the idea for OS/2 was hatched, but they had ample time to change direction later, as "Windows 386" did. Once IBM got their plans right, they produced OS/2 2.0 and shortly after OS/2 2.11, which were fully preemptive OSes with a nearly perfect "DOS box", that is, a way of executing DOS programs in "virtual 386" mode. Windows NT was a solution to the very same problem, and a much inferior one until just recently. Windows 95 in contrast, and 98, 98SE, and ME, were still hybrids - cooperative tasking without full preemption. So Microsoft screwed the same pooch three times, and still won the game. The "DOS box" on early versions of Windows NT was, in contrast to that of OS/2, a total disaster. However, it didn't bite many people because by then, Microsoft had also captured the market for applications. You can still see the DOS box in action - fire up an old DOS program or 16bit Windows program under Windows XP, and look in the task list - you'll see "ntvdm", "NT Virtual DOS machine". -drl The real issue is the “mode switch”, which was nearly impossible on the 286. IBM had no 386 to shoot at when the idea for OS/2 was hatched, but they had ample time to change direction later, as “Windows 386″ did. Once IBM got their plans right, they produced OS/2 2.0 and shortly after OS/2 2.11, which were fully preemptive OSes with a nearly perfect “DOS box”, that is, a way of executing DOS programs in “virtual 386″ mode. Windows NT was a solution to the very same problem, and a much inferior one until just recently. Windows 95 in contrast, and 98, 98SE, and ME, were still hybrids – cooperative tasking without full preemption. So Microsoft screwed the same pooch three times, and still won the game.

The “DOS box” on early versions of Windows NT was, in contrast to that of OS/2, a total disaster. However, it didn’t bite many people because by then, Microsoft had also captured the market for applications.

You can still see the DOS box in action – fire up an old DOS program or 16bit Windows program under Windows XP, and look in the task list – you’ll see “ntvdm”, “NT Virtual DOS machine”.

-drl

]]> By: Larry Osterman http://www.math.columbia.edu/~woit/wordpress/?p=149&cpage=1#comment-2287 Larry Osterman Wed, 31 Dec 1969 19:00:00 +0000 http://www.math.columbia.edu/~woit/wordpress/?p=149#comment-2287 Thanks D.R., I'll make the corrections... For some reason I'd assumed their PhDs came from MIT, don't ask why. Thanks D.R., I’ll make the corrections… For some reason I’d assumed their PhDs came from MIT, don’t ask why.

]]> By: D R Lunsford http://www.math.columbia.edu/~woit/wordpress/?p=149&cpage=1#comment-2288 D R Lunsford Wed, 31 Dec 1969 19:00:00 +0000 http://www.math.columbia.edu/~woit/wordpress/?p=149#comment-2288 I thought the point was, that OS/2 ran on the 286 in protected mode, but the problem was getting into real mode again. Thus, OS/2 had a devil of a time running DOS programs. The 386 had a "virtual DOS mode" so it could go in and out of real mode at will. Windows was targeted at the 386 and the rest is history. -drl I thought the point was, that OS/2 ran on the 286 in protected mode, but the problem was getting into real mode again. Thus, OS/2 had a devil of a time running DOS programs. The 386 had a “virtual DOS mode” so it could go in and out of real mode at will. Windows was targeted at the 386 and the rest is history.

-drl

]]> By: Larry Osterman's WebLog http://www.math.columbia.edu/~woit/wordpress/?p=149&cpage=1#comment-2289 Larry Osterman's WebLog Wed, 31 Dec 1969 19:00:00 +0000 http://www.math.columbia.edu/~woit/wordpress/?p=149#comment-2289 <strong>re: Farewell to one of the great ones</strong> re: Farewell to one of the great ones

]]> By: Larry Osterman's WebLog http://www.math.columbia.edu/~woit/wordpress/?p=149&cpage=1#comment-2290 Larry Osterman's WebLog Wed, 31 Dec 1969 19:00:00 +0000 http://www.math.columbia.edu/~woit/wordpress/?p=149#comment-2290 <strong>Farewell to one of the great ones</strong> Farewell to one of the great ones

]]> By: Larry Osterman's WebLog http://www.math.columbia.edu/~woit/wordpress/?p=149&cpage=1#comment-2291 Larry Osterman's WebLog Wed, 31 Dec 1969 19:00:00 +0000 http://www.math.columbia.edu/~woit/wordpress/?p=149#comment-2291 <strong>Farewell to one of the great ones</strong> Farewell to one of the great ones

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