From mboxrd@z Thu Jan  1 00:00:00 1970
Message-ID: <09bc4af6170d58bf7301230f8f37b748@vitanuova.com>
To: 9fans@cse.psu.edu
Subject: Re: [9fans] ctrl-d and rio
Date: Thu,  4 Nov 2004 18:52:40 +0000
From: rog@vitanuova.com
In-Reply-To: <334ef3045cd1529b82e0bf9767ba99f5@plan9.ucalgary.ca>
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> never been bothered by it enough to look at the cause and assumed it's
> just open file descriptors.  still, i am interested in hearing
> explanations/solutions.

this has nagged at me too in the past, so i just had a look into it.

there are two reasons (in in the plumber case, at any rate)
why the shell window doesn't disappear correctly.
the first is a bug in /sys/src/cmd/plumb/fsys.c:/^startfsys

	procrfork(fsysproc, nil, Stack, RFFDG);

should be:

	procrfork(fsysproc, nil, Stack, RFFDG|RFNAMEG);

otherwise the process serving the plumbing namespace is also holding
that namespace open.

but even with that fixed, the plumber automatically creates an entry
in /srv.  this holds the 9p pipe to the plumber open even when the
shell holding the plumber's namespace exits.

removing the /srv file allows the window to disappear correctly (a rio
window only exits when the window's namespace is no longer
referenced).

so, assuming the first fix,

	plumber
	rm `{cat /env/plumbsrv}

would be sufficient (although an option suppressing the /srv posting
would likely be preferable).