Path: utzoo!utgpu!jarvis.csri.toronto.edu!mailrus!uwm.edu!zaphod.mps.ohio-state.edu!usc!srhqla!elrond.locus.com!ghb
From: ghb@locus.com (George Bray)
Newsgroups: comp.mail.mush
Subject: Another 'longjmp botch'...
Summary: Is it just me?
Message-ID: <255@elrond.locus.com>
Date: 10 Mar 90 06:25:54 GMT
Reply-To: ghb@elrond.locus.com (George Bray)
Organization: Locus Computing Corp., Los Angeles
Lines: 51

Well, I've found another one.  (This is after installing the quickie
patch you sent).  In fact, this may even be the same race condition,
but it has a very different stack trace, so I'm bugging the world
about it again.  As a reminder, this is 7.0.4 (plus change to mail.c)
running under 4.3Tahoe on a Vax.

This time I got a longjmp botch repeatably while reading a
particular mail message.  It turned out that the mail message had an
escape sequence in it.  I reproduce below the line that caused all the
trouble, except that I've turned the escape into the two characters
'^[' and the backspaces into '^H'.

-- The offending line --
you gave to ^[4~Bryan Freed woi^H^Hork now?).
-- End offending line --

The failure only occurred on my Wyse 60 terminal.  The ESC 4 sequence
is 'send unprotected cursor line' which I assume means send the entire
line containing the cursor as input.  

When I displayed the message containing this (using the internal
pager), it would eventually die with a longjmp botch.  The stack trace
follows:

	_longjmp(14) from 17875
	_curses_command(0) from 139bf
	_do_loop() from 97e
	_main(2,40cb0,7fffe8f8) from start+3d

I said above that it would "eventually" die because sometimes the
message would be repeatedly displayed.  In other words, it would
display to the point line containing the escape sequence, the line
would become garbage on the screen, mush would display the
"continue" prompt and then re-display the message.  I'm fairly certain
that the re-display was caused by the line being sent by the terminal
and ending in a CR, which I have bound to display the current message
in curses mode.

It was fairly entertaining watching mush bang itself over the head
with this message until it finally croaked.

Any ideas?  Is this the same race, made worse by machine-speed input?

Thanks,


-- 
George Bray
Locus Computing Corporation, 9800 La Cienega Blvd, Inglewood, CA  90301-4440
213-337-5171
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