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Subject: Infloop in sit-for (was Re: The future of XEmacs)
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From: Steven L Baur <steve@miranova.com>
In-Reply-To: Sudish Joseph's message of 12 Dec 1996 19:34:48 -0500
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Date: 13 Dec 1996 22:55:04 -0800
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>>>>> "Sudish" == Sudish Joseph <sudish@mindspring.com> writes:

Sudish> David Moore <dmoore@UCSD.EDU> writes:
David> The problem seems to be that (sit-for 0) doesn't sometimes, so

Sudish> Input-pending-p can lock as well, as shown by M-x hanoi hanging.
Sudish> Shane Holder reported this a while back on c.e.xemacs.  I just
Sudish> reproduced it with C-u 6 M-x hanoi.

I took a look through the code for sit-for, and it is implemented as
an infinite loop with various exit branches sprinkled throughout.  I
guess the old programming adage about `loops not designed to exit
normally sometimes don't' applies here :-(.

-- 
steve@miranova.com baur
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