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From: alarson@SRC.Honeywell.COM (Aaron Larson)
Newsgroups: gnu.emacs.bug
Subject: Re: Re^2: Lock files
Message-ID: <31646@srcsip.UUCP>
Date: 19 Sep 89 14:28:32 GMT
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In-reply-to: pinkas@cadev5.intel.com's message of 18 Sep 89 21:41:54 GMT


   ... You can almost eliminate the problem by using lockf() if you run the
   lock daemon. ...

We thought of doing this, but decided against it.  The following line from
the man page on lockf highlights the problem:

     All locks associated with a file for  a  given  process  are
     removed  when  the file is closed or the process terminates.

Lots of our users typically have dozens of files loaded at one time.  It
would appear impractical to have open file descriptors for all of them.  I
guess you would only have to have the modified buffer files open, however
in pre 4.0 SunOS the open file restriction was pretty low, even with 4.x
limits it may not be practical, and I don't know what other operating
system open file limits are like.