From owner-freebsd-hackers  Wed Mar 19 01:06:08 1997
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To: Mike Pritchard <mpp@freefall.freebsd.org>
cc: hackers@freebsd.org
Subject: Re: dup3() - I've thought it over and decided... 
In-reply-to: Your message of "Tue, 18 Mar 1997 23:36:12 PST."
             <199703190736.XAA09452@freefall.freebsd.org> 
Date: Wed, 19 Mar 1997 01:06:03 -0800
Message-ID: <20682.858762363@time.cdrom.com>
From: "Jordan K. Hubbard" <jkh@time.cdrom.com>
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> How about going more along the checkpoint/restart route?  Suspend
> the process, checkpoint it, and on restart you can reconnect stdin/out/err
> to either the current tty, or to another file.  Reconnecting to
> a pipeline should also be possible.  I can dig up the USENIX paper
> the Cray guys wrote on this if you like :-).

Does the checkpoint feature allow you to complete snapshot process
state?  That's another item on my wishlist. :-)

I wouldn't mind reading that paper, if you can dig it up.

Anyone remember a timesharing system called ITS (from MIT)?  If you
got disconnected from the modem (not uncommon in those days of
Pennywhistle, 300 baud acoustically-coupled modems :-) you wouldn't
lose your session, like you do under UNIX, rather the next time you
logged in it would ask you:

[Attach your detached tree?]

And if you said 'y' you'd get your old process tree back, everything
right where you left it.

Now I'm not sure if ITS accomplished this by leaving your processes
suspended and under the ownership of some foster parent for a certain
period of time, or if it genuinely saved them to disk and then
resurrected them on demand, but it sure was a bloody convenient
feature which I've always missed! :-)

					Jordan