Path: utzoo!utgpu!cunews!bnrgate!brchh104!brchs1!bnr.ca!rice.edu!sun-spots-request
From: eap@bu-it.bu.edu (Eric A. Pearce)
Newsgroups: comp.sys.sun
Subject: Safe updating of shared libs/binaries
Keywords: Miscellaneous
Message-ID: <2684@brchh104.bnr.ca>
Date: 28 Apr 91 19:20:00 GMT
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X-Original-Date: 25 Apr 91 19:39:49 GMT
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I'm interested in hearing how other people deal with the problem of
updating shared libraries and executables under SunOS.   The usual result
of just overwriting a running executable or library is that your programs
dies in a big way.   This is pretty disruptive if it's your X server.
Our current level of automation is to run "rdist" and use the "special"
feature, i.e.

	special /usr/lib/lib*X* "/usr/etc/ldconfig" ;

But this really doesn't do much for the crashing problem.   I suppose you
could "mv" the running binary to a new location, copy in the new
executable and remove the old after a certain grace period.  Would you
want setuid programs scooting around in other directories anyways?  This
doesn't make much sense for a shared library (as I understand it) since
the location is set in the cache.

Does anybody have a "clean" solution to this problem?

 Eric Pearce eap@bu-it.bu.edu