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Yesterday I bought a HP LaserJet Pro P1566 printer. The device itself is nice, supported by foo2zjs, though of course that support is unofficial. I was curious what do they offer a "Linux support" on their website, since the case of the printer mentions Linux support. And I had to use the above picture to select my country.
It’s Magyarország, not Magyarorság.
The map of the country isn’t even close to reality, what are they smoking? ;)
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About four days ago it has been asked on #libreoffice if it’s possible
to bind functions to F13..F16 in Calc. The short answer is no, but it
turned out it’s pretty trivial to allow that (and of course not only in
Calc).
Cedric’s great post is helpful here to find the relevant code. It also truned out that VCL already supports those keys, so only the user interface has to be improvied to export that feature.
The patch is here.
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If you use systemd, you know systemctl. That’s the command that
controls systemd: you can use it to start, stop or list (and so on)
services. Now in case you use list, there is a lot of output, probably
it won’t fit your screen. git already invented auto-paging, which means
it’ll feed its output to a pager if the output is more than a screen,
for example when using git log. With my
recent
commit this now the case with systemctl as well. :)
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I released bitlbee-skype 0.9.0 today. The last feature that triggered
the relase born in git during the last two days: now it reads and writes
Skype group info. This means if you have a Skype group "work", then you
can just /j &work to see work contacts only, and /invite also works
in that channel as expected.
More in the BitlBee wiki and in the NEWS file.
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CSP, as in Constraint satisfaction problem. A while back I wrote a custom sudoku solver in Erlang, and now I hit something similar. Of course, since then I learned that there are nice CSP engines, so this time I did not try to write my own. :)
First, I checked out python-constraint, and then I sticked with it, as it fulfilled my needs.
So, the problem. Here is a Christmas tree:
The tree has 4 chains, each one contains 7 items. A few ones already has a number. The exercise: number the empty items with numbers between 1 and 7 so that:
Each chain contains the numbers 1..7 exactly once.
All the horizontal and diagonal lines cannot contain the same number twice.
A possible solution is here. If you get less or more than one solution, you did something wrong. :) (I’m not pasting here the output of the script to leave some exercise for the readers. ;) )
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Note
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As an experiment this time I draw the image using TikZ. Based on these ideas I converted the source to PNG using tikz2png. |
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Finally I can run systemd on my desktop, and not in a virtual machine only, since there is a patch for the sched/cgroup issue I had. It was not a systemd bug, but systemd triggered a kernel issue, which was hidden so far.
I just updated our bluez package, and bus activation works fine. This means bluetoothd is not started till somebody connects to it. Given that I sometimes do not log in to KDE to use kbluetooth, but just want to do something on the console, where having bluetoothd running is totally unnecessary, I consider this really nice.
It came up on #bitlbee that there is a
Fedora bug where
they ask for systemd unit files for BitlBee. So I
created a patch, and the
nice thing is that the second iteration now seems to be fine for
Frugalware/Fedora/Debian, so we managed to build something cross-distro
here. (I think I mentioned that’s the #1 feature I like in systemd.)
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I wanted to create some calendar present for Christmas in the family with pictures and Hungarian year / month order, national holidays, etc.
After looking at a few solutions, pcal seemed to be the best choice.
There are 3 key points here:
The order of the year / month can be changed only in build-time. If your locale has "year month" and not "month year" order, then you need this patch.
You need some config for each locale, here is mine, containing the Hungarian national holidays.
Finally you need a script like this to put in the pictures.
The result fully localized, free software, contains my custom images and support custom marks for days using a quite flexible syntax.
(Let me know if you know some other project where you can set the year/month order runtime and the result can be still generated from a script, ie. it’s not some LibreOffice or similar template. ;) )
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I needed a tiny tool to generate something classdiagram-like from CORBA IDL files. Given that I did not find such a tool, I wrote it.
You can find it here.
An example: idl → scalable output.
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Right now it does not support typedefs, enums and exceptions. If you need such a feature, patches are welcome. :) |
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I just found this podcast, it’s a bit dated since it happened in August and things have been improved a bit since then, but still I was happy to listen it. (The interesting part starts at 1:10:50; 17 minutes.)
I already had a short post about systemd, and I mentioned the killer feature for me is the compact distro-independent service file (initscript for sysvinit) format it uses, since even if the initscript format we use in Frugalware right now is mostly bullshit-free, it’s still more bloated than the systemd service files.
Now back to why I began writing this post. :) So there is the post about systemd, but it’s rather long, and it’s easy to miss the point. Since the previous post, I think there are a few more killer features in systemd:
Every service is started in a separate control group (cgroup). Do you remember the situation when you wanted to know who the hell started a given particular process? This is typically a problem if the process is running as root. Now this is no longer a problem, systemd-cgls will show you if it was started by a user or a given service, etc. (Yes, I consider this a security feature.)
Upstart already had this "restart if it crashed" feature, but systemd does it better: if the daemon supports socket activation, then messages sent to the socket are buffered by the kernel, and no message will be lost during the restart.
systemd provides this on-demand feature, which is pretty much like inetd, so hopefully we can get rid of inetd, which was a constant problem previously. (We inherited a fork of the OpenBSD inetd from Slackware, and being a fork it did not improve since years, causing a constant problem.)
Why writing this post today? Because this morning systemd appeared in -current, so you can even try it out without installing any unofficial package.
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So we have this systemd wip repo and one of the remaining todo items was to fix up splashy to work with systemd.
First, why doesn’t it out of the box of systemd is a drop-in
replacement? Because splashy is not a simple init script, it hooks
itself to rc.sysvinit, so it was specific to sysvinit.
Now given that plymouth was already ported to systemd, it served as a good example. You may also ask: why don’t we just switch to plymouth? Because:
we don’t want to introduce multiple changes at the same time
it requires kms, while Splashy did not require it - so as long as it’s not true that most video cards support kms (think of via or anything else which supports vesafb, but not kms), such a switch would be a regression
Okay, enough anti-Plymouth rant. As you can see, right now the task is to fix Splashy.
The steps I did were:
updated the Splashy theme to remove the progressbar: given that now we start services parallel and on-demand, it does not really make too much sense
introduced unit files: to start on boot, to stop before getty/xorg, to start before kexec/reboot/halt/poweroff
added the usual compatibility symlinks to avoid starting the old rc.splash (which would happen anyway)
added a simple wrapper that fires up splashy and once it’s ready it sends the Booting…/Rebooting…/etc text to it
The last problem is a bit more complex: now that xorg startup wants to
stop splashy, a dependency has to be declared. xorg startup is handled
by prefdm.service, but in case it depends on splashy-quit.service,
what will happen if you don’t have or don’t want a splash?
The solution for now is to declare an After= relation: that means xorg
startup will happen after the quit of splashy, if it happens at all.
This way:
you can disable the splash, it won’t cause any dependency errors
if you don’t have prefdm.service enabled, you can even have splashy
uninstalled
(this one is a bit ugly) you can disable the splash, but if you
uninstall it and have prefdm.service enabled, you’ll get a
dependency error, as systemd will have no idea what
splashy-quit.service is.
To test the above:
you need to enable the systemd wip repo (see the link above)
run pacman-g2 -Sy systemd
boot with init=/bin/systemd
Stay tuned, we still have a few blocker issues before merging the (disabled by default, as you need that kernel parameter) systemd support to current.