Shallow Thoughts : : Feb
Akkana's Musings on Open Source Computing, Science, and Nature.
Sun, 05 Feb 2006
I've been unable to persuade Ubuntu's "Dapper Drake" to log me in
automatically via gdm. My desktop background flashes briefly during
the login process, then vanishes; it appears that it actually is
logging me in briefly, then immediately logging me out and presenting
me with the normal gdm login screen.
I never liked gdm much anyway. It's heavyweight and it interferes with
seeing shutdown messages. The only reason I was using it on Hoary
was for autologin, and with that reason gone, I uninstalled it.
But that presented an interesting problem: it turns out that
Dapper doesn't actually allow users to run X. The error message is:
Unable to open wrapper config file /etc/X11/Xwrapper.config
X: user not authorized to run the X server, aborting.
The fix turned out to be trivial: make the X server setuid
and setgid (chmod 6755 /usr/bin/X
). Mode 4755 (setuid only,
no setgid) also works, but other Debian systems seem to set both bits.
The next question was how to implement auto-login without gdm or kdm.
I had already found a useful
article on the subject. The gist is that you compile a short C
program that calls login with your username, then you call getty with
your new program as the "alternate login program".
Now, I have nothing against C, but wouldn't a script be easier?
It turns out a script works too. Replace the tty1 line in
/etc/inittab with a line like:
1:2345:respawn:/sbin/getty -n -l /usr/bin/myloginscript 38400 tty1
where the script in question looks like:
/bin/login -f username
At first, I tried an even simpler approach:
1:2345:respawn:/bin/login -f username
That logged me in, but I ended up on /dev/console instead of
/dev/tty1, with a message that I had no access to the tty and
therefore wouldn't be able to use job control. X didn't work
either. The getty is needed in order to switch control
from /dev/console to a real virtual terminal like /dev/tty1.
Of course, running X automatically once you're logged in is trivial,
just a line or three added to .login or .profile (see the Linux
Gazette article referenced above for an example).
It works great, it's very fast, plus I can watch shutdown messages
Update 9/9/2006: the Linux Gazette article isn't accessible any more
(apparently Linux Journal bought them and made the old articles
inaccessible). But here's an example of what I do in my .login
on Dapper -- this is for tcsh, so bash users subtitute "fi" for "endif":
if ($tty == tty1) then
[ 10:53 Feb 05, 2006
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Sat, 04 Feb 2006
I've been meaning to upgrade my desktop machine from Ubuntu's "Hoary
Hedgehog" release for some time -- most notably so that I can get the
various packages needed to run GTK 2.8, which is now required to build
the most current GIMP.
Although I'm having good success with "Breezy Badger", the stable
Ubuntu successor to "Hoary", on my laptop, Breezy is already
borderline as far as GIMP requirements, and that can only get worse.
Since I do more development on the desktop, I figured
it was worth trying one of the pre-released versions of Ubuntu's
next release, "Dapper Drake".
Wins over hoary and breezy: it handles my multiple flash card reader
automatically (on hoary and breezy I had to hack the udev
configuration file to make it work).
I've had a few glitches, starting with the first auto-update wanting
to install a bunch of packages that didn't actually exist on the
server. This persisted for about a week, during which I got a list
of 404s and "packages held back" warnings every time I updated or
installed anything. It didn't seem to hurt anything -- just a minor
irritant -- and it did eventually get fixed. That's life with an
Dapper has the same problem that hoary and
breezy have with hald polling the hard disk every few seconds
In addition, hald seems to spawn a rather large number of
(probably to handle the built-in multi flash card reader).
(Uncommenting the storage.automount_enabled_hint in
/etc/hal/fdi/policy/preferences.fdi didn't help.)
Killing hald (and nuking /usr/sbin/hald
so it won't restart) solves both these problems, but it also
stops hotplugged USB devices from working: apparently Dapper
has switched to using hal instead of hotplug for USB. Ouch!
In any case, hald came back on a dist-upgrade so it looks like
I'll have to find a more creative solution.
The printing packages have problems.
I tried to add my printer via the CUPS web interface,
but apparently it didn't install any printer drivers by default, and
it's not at all obvious where to get them. The drivers are there, in
/usr/share/cups/model/gutenprint/5.0/en, but dapper's cups apparently
isn't looking there. I eventually got around the problem by
uncompressing the ppd file and pointing CUPS directly at
Dapper's ImageMagick has a bug in the composite command:
basically, you can't combine two images at all. So I have to generate
web page thumbnails on another machine until that's fixed.
gdm refuses to set up my user for auto-login, and I hit an interesting
localization issue involving GIMP (I'll report on those issues separately).
Most other things work pretty well. Dapper has a decent set of
multimedia apps and codecs, and its kernel and udev setup seem to work
fine (it can't suspend my desktop machine, but neither can any other
distro, and I don't really need that anyway).
Except for the hald problem, Dapper looks like a very usable system.
[ 18:27 Feb 04, 2006
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Thu, 02 Feb 2006
In early December, a squirrel staked out our yard as part of his
territory. We encouraged him with nuts. He has a notch in one ear,
so I called him "Notch".
Later that month, another squirrel showed up. Sometimes Notch chased
the new squirrel (especially when food was involved), but at other
times they seemed to be playing in a friendly way. Apparently
December is breeding time for squirrels.
There's no easy way to identify the gender of grey squirrels (at
least from a distance), so we arbitrarily decided that the larger,
tougher and more territorial Notch was a male, and the newcomer
must be female. Dave dubbed her "Nonotchka".
(Of course we're hoping that in a few months it will become obvious
which one is actually the female, and soon afterward we will have
little squirrels to watch.)
Both Notch and Nonotchka have become rather tame (though not quite
to the point of taking food from our hands), and we've been able to
get some decent (though not spectacular) photos while feeding them.
Unfortunately, the final review process for the GIMP book got in the
way of organizing the photos or writing squirrel essays, and I'm
only now starting to catch up.
So here they are: our
[ 14:57 Feb 02, 2006
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