Subject: Re: persistent/restorable unix procs?
To: Travis Hassloch <>
From: Brett Lymn <>
List: current-users
Date: 11/29/1995 17:34:19
According to Travis Hassloch:
>Has anyone done any work on (or looking into) how one might dump a process's
>state to disk & restore it, assuming it's a cooperating process?
>E.G. maybe you have a process that wants to save itself on purpose.
>To make it harder, how about an uncooperative process?
>Is this possible under stock Unix (specifically, stock NetBSD)?

Apparently this is possible, at the last AUUG conference there was a
guy called Chris Maltby from Softway that had a talk about, in vague
terms, what is involved in saving the state of the process.  In short,
even with a cooperating process there is a lot of state information
hidden in all sorts of places that must be saved to succeed in
restarting the process, not all of it is in the proc structure.  Other
wrinkles are what happens if the process is part of a pipeline.

>From what Chris said in his talk it sounded like they had managed to
make it work, unfortunately for us I think that Chris & Co. are hoping
to make money on what they have done so the gritty details of what
they have done are, more than likely, unavailable.

Brett Lymn, Computer Systems Administrator, AWA Defence Industries
  "Upgrading your memory gives you MORE RAM!" - ad in MacWAREHOUSE catalogue.