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From: michaud@decvax.dec.com (Jeff Michaud)
Newsgroups: comp.unix.wizards
Subject: Re: "Check pointing" on BSD Unix (or Ultrix)
Keywords: gcore checkpoint dbx
Message-ID: <6150@shlump.nac.dec.com>
Date: 15 Nov 89 19:54:27 GMT
References: <1326@utkcs2.cs.utk.edu>
Sender: news@shlump.nac.dec.com
Organization: DEC
Lines: 21

> What I would like to be able to do would be to stop a running process,
> save it's core image to a file (similar to what gcore(1) does), kill
> the original process, and then later (like, say, after rebooting)
> restart the process from the saved core image.

	It would be easiest if the application knew how to checkpoint itself.

	One of the biggy problems you are going to have trying to checkpoint then
	restart as a new process without cooperation from application is restoring
	open file descriptors.  You may be able to reopen normal files, but if the
	application had sockets open talking to someone else, it would be impossible
	to restore that state w/out the application being restarted knowing.

	You may want to look into the Tex/LaTeX distro.  TeX can dump itself and
	be massaged to create a new executable that includes newly built in
	style/macro files.

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|Jeff Michaud    michaud@decwrl.dec.com  michaud@decvax.dec.com|
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