Subject: Re: persistent/restorable unix procs?
To: Travis Hassloch <travis@evtech.com>
From: David Leonard <leonard@dstc.edu.au>
List: current-users
Date: 11/29/1995 15:26:55
> 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)?
>
> I know there are some issues regarding shared code segments...
> Probably a lot more issues regarding stuff that isn't exactly in it's
> address space... I'm wondering if someone has attacked this thing already.
> ...it's just something I've been musing over w.r.t rollbacks and/or
> window manager "sessions"...
>
> CC me in replies, thanks....
I seem to recall an `undump' feature of sunos - the perl manpage also talks
about it, essentially the program calls abort() and the core file can be
`undumped' into another executable that when run restores the process
image. Unsure if netbsd can do this (no manpage on it).
I think there would be problems with file descriptors and such, but i
dont know - I've never tried it. Some prolog engine i built once also
did something similar (`undumped' itself so it initialised quicker).
hth
d
--
David Leonard BE(Comp)/BCompSc 5th year student
The University of Queensland s160828@student.uq.edu.au
perl -e 'for $c(split(//,"BILLGATES\003")){$s+=ord($c)};print $s."\n"'