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Path: utzoo!utgpu!jarvis.csri.toronto.edu!rutgers!bellcore!att!cbnewsh!ho5cad!wjc
From: wjc@ho5cad.ATT.COM (Bill Carpenter)
Newsgroups: comp.emacs,gnu.emacs.gnus
Subject: interaction between GNUS and VM
Message-ID: <WJC.89Jul21233546@ho5cad.ho5cad.ATT.COM>
Date: 21 Jul 89 22:35:46 GMT
Sender: bill@cbnewsh.ATT.COM
Reply-To: wjc@ho5cad.ATT.COM (Bill Carpenter)
Organization: AT&T Bell Laboratories
Lines: 30

I use GNUS to read news and VM to read mail (thanks to both authors
for providing them!).  I have noticed the following undesirable
interaction between these two fine packages.

1.  Select a group and get to *Article* buffer of GNUS.

2.  Notice you have mail and invoke VM.  Quit from VM.

3.  Try to select an article for reading and get "invalid argument,
markerp nil".

4.  Get out of the *Article* buffer by normal means.  Kill the
*Article* buffer.  All is now seemingly better.

Through trial and error and random roaming around, I have sort of
figured out that this error message comes from this line in
gnus-Article-prepare: (set-marker overlay-arrow-position nil).  Based
on the hint that killing the *Article* buffer and recreating it seemed
to fix the problem, I did this in the *Article* buffer:

    (make-variable-buffer-local 'overlay-arrow-position)

This seemed to fix things also, so I figure I can just whip that into
a hook someplace in GNUS.  However, I have only a vague notion of
where overlay-arrow-position is used, and I'm wondering if there is
any harm in having it be buffer-local.

Anybody got a guess (or a better way to fix this)?
--
   Bill Carpenter         att!ho5cad!wjc  or  attmail!bill