[9fans] Re: plan9port: recent changes

[Russ Cox <russcox@gmail.com>]

A few people have reported that running acme and exiting
leaves behind a 9pserve process with the effect that you can't
run acme a second time.  I believe I just checked in a fix to this bug,
which I introduced trying to work around the pthread nonsense
we were discussing last week.  After updating from CVS, you'll
have to rebuild libthread and then 9pserve (or just use
cd $PLAN9; ./INSTALL -- it's still much faster than compiling the
Linux kernel).

It's worth noting for everyone that you can't run two acmes in
the same "name space" since they'll both want to post as the Unix
socket `namespace`/acme.  If you want to start a new "name space"
you can set $NAMESPACE manually, as in

    mkdir /tmp/ns; NAMESPACE=/tmp/ns; export NAMESPACE

and then you'll have a separate acme that is isolated from the
first (and from the plumber that the first acme is using).

Intro(4) has details.

Setting $NAMESPACE also lets you run file servers before you
start X and share them with your X session.  For example, in my
.profile I have the following:

# Logging in on tty1 sets up factotum and then runs X automatically
if [ "`/bin/ls -l /proc/self/fd/0 2>/dev/null | awk '{print $NF}'`" =
'/dev/tty1' ]
then
	NAMESPACE=/tmp/ns.`hostname`
	export NAMESPACE
	rm -rf $NAMESPACE; mkdir $NAMESPACE
	9 factotum
	eval `9 ssh-agent -e`
	startx
fi

I have to start factotum and ssh-agent before X because I run
stats to remote machines (via ssh) in my .xinitrc, and so that
the $SSH_AUTH_SOCK variable is set in all my X windows.

Russ