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        <channel>
                <title>Petter Reinholdtsen</title>
                <description></description>
                <link>http://people.skolelinux.org/pere/blog/</link>
                <atom:link href="http://people.skolelinux.org/pere/blog/index.rss" rel="self" type="application/rss+xml" />
        
        <item>
                <title>Coz can help you find bottlenecks in multi-threaded software - nice free software</title>
                <link>http://people.skolelinux.org/pere/blog/Coz_can_help_you_find_bottlenecks_in_multi_threaded_software___nice_free_software.html</link>
                <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Coz_can_help_you_find_bottlenecks_in_multi_threaded_software___nice_free_software.html</guid>
                <pubDate>Thu, 11 Aug 2016 12:00:00 +0200</pubDate>
                <description>&lt;p&gt;This summer, I read a great article
&quot;&lt;a href=&quot;https://www.usenix.org/publications/login/summer2016/curtsinger&quot;&gt;coz:
This Is the Profiler You&#39;re Looking For&lt;/a&gt;&quot; in USENIX ;login: about
how to profile multi-threaded programs.  It presented a system for
profiling software by running experiences in the running program,
testing how run time performance is affected by &quot;speeding up&quot; parts of
the code to various degrees compared to a normal run.  It does this by
slowing down parallel threads while the &quot;faster up&quot; code is running
and measure how this affect processing time.  The processing time is
measured using probes inserted into the code, either using progress
counters (COZ_PROGRESS) or as latency meters (COZ_BEGIN/COZ_END).  It
can also measure unmodified code by measuring complete the program
runtime and running the program several times instead.&lt;/p&gt;

&lt;p&gt;The project and presentation was so inspiring that I would like to
get the system into Debian.  I
&lt;a href=&quot;https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=830708&quot;&gt;created
a WNPP request for it&lt;/a&gt; and contacted upstream to try to make the
system ready for Debian by sending patches.  The build process need to
be changed a bit to avoid running &#39;git clone&#39; to get dependencies, and
to include the JavaScript web page used to visualize the collected
profiling information included in the source package.
But I expect that should work out fairly soon.&lt;/p&gt;

&lt;p&gt;The way the system work is fairly simple.  To run an coz experiment
on a binary with debug symbols available, start the program like this:

&lt;p&gt;&lt;blockquote&gt;&lt;pre&gt;
coz run --- program-to-run
&lt;/pre&gt;&lt;/blockquote&gt;&lt;/p&gt;

&lt;p&gt;This will create a text file profile.coz with the instrumentation
information.  To show what part of the code affect the performance
most, use a web browser and either point it to
&lt;a href=&quot;http://plasma-umass.github.io/coz/&quot;&gt;http://plasma-umass.github.io/coz/&lt;/a&gt;
or use the copy from git (in the gh-pages branch).  Check out this web
site to have a look at several example profiling runs and get an idea what the end result from the profile runs look like.  To make the
profiling more useful you include &amp;lt;coz.h&amp;gt; and insert the
COZ_PROGRESS or COZ_BEGIN and COZ_END at appropriate places in the
code, rebuild and run the profiler.  This allow coz to do more
targeted experiments.&lt;/p&gt;

&lt;p&gt;A video published by ACM
&lt;a href=&quot;https://www.youtube.com/watch?v=jE0V-p1odPg&quot;&gt;presenting the
Coz profiler&lt;/a&gt; is available from Youtube.  There is also a paper
from the 25th Symposium on Operating Systems Principles available
titled
&lt;a href=&quot;https://www.usenix.org/conference/atc16/technical-sessions/presentation/curtsinger&quot;&gt;Coz:
finding code that counts with causal profiling&lt;/a&gt;.&lt;/p&gt;

&lt;p&gt;&lt;a href=&quot;https://github.com/plasma-umass/coz&quot;&gt;The source code&lt;/a&gt;
for Coz is available from github.  It will only build with clang
because it uses a
&lt;a href=&quot;https://gcc.gnu.org/bugzilla/show_bug.cgi?id=55606&quot;&gt;C++
feature missing in GCC&lt;/a&gt;, but I&#39;ve submitted
&lt;a href=&quot;https://github.com/plasma-umass/coz/pull/67&quot;&gt;a patch to solve
it&lt;/a&gt; and hope it will be included in the upstream source soon.&lt;/p&gt;

&lt;p&gt;Please get in touch if you, like me, would like to see this piece
of software in Debian.  I would very much like some help with the
packaging effort, as I lack the in depth knowledge on how to package
C++ libraries.&lt;/p&gt;
</description>
        </item>
        
        <item>
                <title>Sales number for the Free Culture translation, first half of 2016</title>
                <link>http://people.skolelinux.org/pere/blog/Sales_number_for_the_Free_Culture_translation__first_half_of_2016.html</link>
                <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Sales_number_for_the_Free_Culture_translation__first_half_of_2016.html</guid>
                <pubDate>Fri, 5 Aug 2016 22:45:00 +0200</pubDate>
                <description>&lt;p&gt;As my regular readers probably remember, the last year I published
a French and Norwegian translation of the classic
&lt;a href=&quot;http://www.free-culture.cc/&quot;&gt;Free Culture book&lt;/a&gt; by the
founder of the Creative Commons movement, Lawrence Lessig.  A bit less
known is the fact that due to the way I created the translations,
using docbook and po4a, I also recreated the English original.  And
because I already had created a new the PDF edition, I published it
too.  The revenue from the books are sent to the Creative Commons
Corporation.  In other words, I do not earn any money from this
project, I just earn the warm fuzzy feeling that the text is available
for a wider audience and more people can learn why the Creative
Commons is needed.&lt;/p&gt;

&lt;p&gt;Today, just for fun, I had a look at the sales number over at
Lulu.com, which take care of payment, printing and shipping.  Much to
my surprise, the English edition is selling better than both the
French and Norwegian edition, despite the fact that it has been
available in English since it was first published.  In total, 24 paper
books was sold for USD $19.99 between 2016-01-01 and 2016-07-31:&lt;/p&gt;

&lt;table border=&quot;0&quot;&gt;
&lt;tr&gt;&lt;th&gt;Title / language&lt;/th&gt;&lt;th&gt;Quantity&lt;/th&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td&gt;&lt;a href=&quot;http://www.lulu.com/shop/lawrence-lessig/culture-libre/paperback/product-22645082.html&quot;&gt;Culture Libre / French&lt;/a&gt;&lt;/td&gt;&lt;td align=&quot;right&quot;&gt;3&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td&gt;&lt;a href=&quot;http://www.lulu.com/shop/lawrence-lessig/fri-kultur/paperback/product-22441576.html&quot;&gt;Fri kultur / Norwegian&lt;/a&gt;&lt;/td&gt;&lt;td align=&quot;right&quot;&gt;7&lt;/td&gt;&lt;/tr&gt;
&lt;tr&gt;&lt;td&gt;&lt;a href=&quot;http://www.lulu.com/shop/lawrence-lessig/free-culture/paperback/product-22440520.html&quot;&gt;Free Culture / English&lt;/a&gt;&lt;/td&gt;&lt;td align=&quot;right&quot;&gt;14&lt;/td&gt;&lt;/tr&gt;
&lt;/table&gt;

&lt;p&gt;The books are available both from Lulu.com and from large book
stores like Amazon and Barnes&amp;Noble.  Most revenue, around $10 per
book, is sent to the Creative Commons project when the book is sold
directly by Lulu.com.  The other channels give less revenue.  The
summary from Lulu tell me 10 books was sold via the Amazon channel, 10
via Ingram (what is this?) and 4 directly by Lulu.  And Lulu.com tells
me that the revenue sent so far this year is USD $101.42.  No idea
what kind of sales numbers to expect, so I do not know if that is a
good amount of sales for a 10 year old book or not.  But it make me
happy that the buyers find the book, and I hope they enjoy reading it
as much as I did.&lt;/p&gt;

&lt;p&gt;The ebook edition is available for free from
&lt;a href=&quot;https://github.com/petterreinholdtsen/free-culture-lessig&quot;&gt;Github&lt;/a&gt;.&lt;/p&gt;

&lt;p&gt;If you would like to translate and publish the book in your native
language, I would be happy to help make it happen.  Please get in
touch.&lt;/p&gt;
</description>
        </item>
        
        <item>
                <title>Vitenskapen tar som vanlig feil igjen - relativt feil</title>
                <link>http://people.skolelinux.org/pere/blog/Vitenskapen_tar_som_vanlig_feil_igjen___relativt_feil.html</link>
                <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Vitenskapen_tar_som_vanlig_feil_igjen___relativt_feil.html</guid>
                <pubDate>Mon, 1 Aug 2016 16:00:00 +0200</pubDate>
                <description>&lt;p&gt;For mange år siden leste jeg en klassisk tekst som gjorde såpass
inntrykk på meg at jeg husker den fortsatt, flere år senere, og bruker
argumentene fra den stadig vekk.  Teksten var «The Relativity of
Wrong» som Isaac Asimov publiserte i Skeptical Inquirer i 1989.  Den
gir litt perspektiv rundt formidlingen av vitenskapelige resultater.
Jeg har hatt lyst til å kunne dele den også med folk som ikke
behersker engelsk så godt, som barn og noen av mine eldre slektninger,
og har savnet å ha den tilgjengelig på norsk.  For to uker siden tok
jeg meg sammen og kontaktet Asbjørn Dyrendal i foreningen Skepsis om
de var interessert i å publisere en norsk utgave på bloggen sin, og da
han var positiv tok jeg kontakt med Skeptical Inquirer og spurte om
det var greit for dem.  I løpet av noen dager fikk vi tilbakemelding
fra Barry Karr hos The Skeptical Inquirer som hadde sjekket og fått OK
fra Robyn Asimov som representerte arvingene i Asmiov-familien og gikk
igang med oversettingen.&lt;/p&gt;

&lt;p&gt;Resultatet, &lt;a href=&quot;http://www.skepsis.no/?p=1617&quot;&gt;«Relativt
feil»&lt;/a&gt;, ble publisert på skepsis-bloggen for noen minutter siden.
Jeg anbefaler deg på det varmeste å lese denne teksten og dele den med
dine venner.&lt;/p&gt;

&lt;p&gt;For å håndtere oversettelsen og sikre at original og oversettelse
var i sync brukte vi git, po4a, GNU make og Transifex.  Det hele
fungerte utmerket og gjorde det enkelt å dele tekstene og jobbe sammen
om finpuss på formuleringene.  Hadde hosted.weblate.org latt meg
opprette nye prosjekter selv i stedet for å måtte kontakte
administratoren der, så hadde jeg brukt weblate i stedet.&lt;/p&gt;
</description>
        </item>
        
        <item>
                <title>Techno TV broadcasting live across Norway and the Internet (#debconf16, #nuug) on @frikanalen</title>
                <link>http://people.skolelinux.org/pere/blog/Techno_TV_broadcasting_live_across_Norway_and_the_Internet___debconf16___nuug__on__frikanalen.html</link>
                <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Techno_TV_broadcasting_live_across_Norway_and_the_Internet___debconf16___nuug__on__frikanalen.html</guid>
                <pubDate>Mon, 1 Aug 2016 10:30:00 +0200</pubDate>
                <description>&lt;p&gt;Did you know there is a TV channel broadcasting talks from DebConf
16 across an entire country?  Or that there is a TV channel
broadcasting talks by or about
&lt;a href=&quot;http://beta.frikanalen.no/video/625529/&quot;&gt;Linus Torvalds&lt;/a&gt;,
&lt;a href=&quot;http://beta.frikanalen.no/video/625599/&quot;&gt;Tor&lt;/a&gt;,
&lt;a href=&quot;http://beta.frikanalen.no/video/624019/&quot;&gt;OpenID&lt;/A&gt;,
&lt;a href=&quot;http://beta.frikanalen.no/video/625624/&quot;&gt;Common Lisp&lt;/a&gt;,
&lt;a href=&quot;http://beta.frikanalen.no/video/625446/&quot;&gt;Civic Tech&lt;/a&gt;,
&lt;a href=&quot;http://beta.frikanalen.no/video/625090/&quot;&gt;EFF founder John Barlow&lt;/a&gt;,
&lt;a href=&quot;http://beta.frikanalen.no/video/625432/&quot;&gt;how to make 3D
printer electronics&lt;/a&gt; and many more fascinating topics?  It works
using only free software (all of it
&lt;a href=&quot;http://github.com/Frikanalen&quot;&gt;available from Github&lt;/a&gt;), and
is administrated using a web browser and a web API.&lt;/p&gt;

&lt;p&gt;The TV channel is the Norwegian open channel
&lt;a href=&quot;http://www.frikanalen.no/&quot;&gt;Frikanalen&lt;/a&gt;, and I am involved
via &lt;a href=&quot;https://www.nuug.no/&quot;&gt;the NUUG member association&lt;/a&gt; in
running and developing the software for the channel.  The channel is
organised as a member organisation where its members can upload and
broadcast what they want (think of it as Youtube for national
broadcasting television).  Individuals can broadcast too.  The time
slots are handled on a first come, first serve basis.  Because the
channel have almost no viewers and very few active members, we can
experiment with TV technology without too much flack when we make
mistakes.  And thanks to the few active members, most of the slots on
the schedule are free.  I see this as an opportunity to spread
knowledge about technology and free software, and have a script I run
regularly to fill up all the open slots the next few days with
technology related video.  The end result is a channel I like to
describe as Techno TV - filled with interesting talks and
presentations.&lt;/p&gt;

&lt;p&gt;It is available on channel 50 on the Norwegian national digital TV
network (RiksTV).  It is also available as a multicast stream on
Uninett.  And finally, it is available as
&lt;a href=&quot;http://beta.frikanalen.no/&quot;&gt;a WebM unicast stream&lt;/a&gt; from
Frikanalen and NUUG.  Check it out. :)&lt;/p&gt;
</description>
        </item>
        
        <item>
                <title>Unlocking HTC Desire HD on Linux using unruu and fastboot</title>
                <link>http://people.skolelinux.org/pere/blog/Unlocking_HTC_Desire_HD_on_Linux_using_unruu_and_fastboot.html</link>
                <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Unlocking_HTC_Desire_HD_on_Linux_using_unruu_and_fastboot.html</guid>
                <pubDate>Thu, 7 Jul 2016 11:30:00 +0200</pubDate>
                <description>&lt;p&gt;Yesterday, I tried to unlock a HTC Desire HD phone, and it proved
to be a slight challenge.  Here is the recipe if I ever need to do it
again.  It all started by me wanting to try the recipe to set up
&lt;a href=&quot;https://blog.torproject.org/blog/mission-impossible-hardening-android-security-and-privacy&quot;&gt;an
hardened Android installation&lt;/a&gt; from the Tor project blog on a
device I had access to.  It is a old mobile phone with a broken
microphone The initial idea had been to just
&lt;a href=&quot;http://wiki.cyanogenmod.org/w/Install_CM_for_ace&quot;&gt;install
CyanogenMod on it&lt;/a&gt;, but did not quite find time to start on it
until a few days ago.&lt;/p&gt;

&lt;p&gt;The unlock process is supposed to be simple: (1) Boot into the boot
loader (press volume down and power at the same time), (2) select
&#39;fastboot&#39; before (3) connecting the device via USB to a Linux
machine, (4) request the device identifier token by running &#39;fastboot
oem get_identifier_token&#39;, (5) request the device unlocking key using
the &lt;a href=&quot;http://www.htcdev.com/bootloader/&quot;&gt;HTC developer web
site&lt;/a&gt; and unlock the phone using the key file emailed to you.&lt;/p&gt;

&lt;p&gt;Unfortunately, this only work fi you have hboot version 2.00.0029
or newer, and the device I was working on had 2.00.0027.  This
apparently can be easily fixed by downloading a Windows program and
running it on your Windows machine, if you accept the terms Microsoft
require you to accept to use Windows - which I do not.  So I had to
come up with a different approach.  I got a lot of help from AndyCap
on #nuug, and would not have been able to get this working without
him.&lt;/p&gt;

&lt;p&gt;First I needed to extract the hboot firmware from
&lt;a href=&quot;http://www.htcdev.com/ruu/PD9810000_Ace_Sense30_S_hboot_2.00.0029.exe&quot;&gt;the
windows binary for HTC Desire HD&lt;/a&gt; downloaded as &#39;the RUU&#39; from HTC.
For this there is is &lt;a href=&quot;https://github.com/kmdm/unruu/&quot;&gt;a github
project named unruu&lt;/a&gt; using libunshield.  The unshield tool did not
recognise the file format, but unruu worked and extracted rom.zip,
containing the new hboot firmware and a text file describing which
devices it would work for.&lt;/p&gt;

&lt;p&gt;Next, I needed to get the new firmware into the device.  For this I
followed some instructions
&lt;a href=&quot;http://www.htc1guru.com/2013/09/new-ruu-zips-posted/&quot;&gt;available
from HTC1Guru.com&lt;/a&gt;, and ran these commands as root on a Linux
machine with Debian testing:&lt;/p&gt;

&lt;p&gt;&lt;pre&gt;
adb reboot-bootloader
fastboot oem rebootRUU
fastboot flash zip rom.zip
fastboot flash zip rom.zip
fastboot reboot
&lt;/pre&gt;&lt;/p&gt;

&lt;p&gt;The flash command apparently need to be done twice to take effect,
as the first is just preparations and the second one do the flashing.
The adb command is just to get to the boot loader menu, so turning the
device on while holding volume down and the power button should work
too.&lt;/p&gt;

&lt;p&gt;With the new hboot version in place I could start following the
instructions on the HTC developer web site.  I got the device token
like this:&lt;/p&gt;

&lt;p&gt;&lt;pre&gt;
fastboot oem get_identifier_token 2&gt;&amp;1 | sed &#39;s/(bootloader) //&#39;
&lt;/pre&gt;

&lt;p&gt;And once I got the unlock code via email, I could use it like
this:&lt;/p&gt;

&lt;p&gt;&lt;pre&gt;
fastboot flash unlocktoken Unlock_code.bin
&lt;/pre&gt;&lt;/p&gt;

&lt;p&gt;And with that final step in place, the phone was unlocked and I
could start stuffing the software of my own choosing into the device.
So far I only inserted a replacement recovery image to wipe the phone
before I start.  We will see what happen next.  Perhaps I should
install &lt;a href=&quot;https://www.debian.org/&quot;&gt;Debian&lt;/a&gt; on it. :)&lt;/p&gt;
</description>
        </item>
        
        <item>
                <title>How to use the Signal app if you only have a land line (ie no mobile phone)</title>
                <link>http://people.skolelinux.org/pere/blog/How_to_use_the_Signal_app_if_you_only_have_a_land_line__ie_no_mobile_phone_.html</link>
                <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/How_to_use_the_Signal_app_if_you_only_have_a_land_line__ie_no_mobile_phone_.html</guid>
                <pubDate>Sun, 3 Jul 2016 14:20:00 +0200</pubDate>
                <description>&lt;p&gt;For a while now, I have wanted to test
&lt;a href=&quot;https://whispersystems.org/&quot;&gt;the Signal app&lt;/a&gt;, as it is
said to provide end to end encrypted communication and several of my
friends and family are already using it.  As I by choice do not own a
mobile phone, this proved to be harder than expected.  And I wanted to
have the source of the client and know that it was the code used on my
machine.  But yesterday I managed to get it working.  I used the
Github source, compared it to the source in
&lt;a href=&quot;https://chrome.google.com/webstore/detail/signal-private-messenger/bikioccmkafdpakkkcpdbppfkghcmihk?hl=en-US&quot;&gt;the
Signal Chrome app&lt;/a&gt; available from the Chrome web store, applied
patches to use the production Signal servers, started the app and
asked for the hidden &quot;register without a smart phone&quot; form.  Here is
the recipe how I did it.&lt;/p&gt;

&lt;p&gt;First, I fetched the Signal desktop source from Github, using

&lt;pre&gt;
git clone https://github.com/WhisperSystems/Signal-Desktop.git
&lt;/pre&gt;

&lt;p&gt;Next, I patched the source to use the production servers, to be
able to talk to other Signal users:&lt;/p&gt;

&lt;pre&gt;
cat &amp;lt;&amp;lt;EOF | patch -p0
diff -ur ./js/background.js userdata/Default/Extensions/bikioccmkafdpakkkcpdbppfkghcmihk/0.15.0_0/js/background.js
--- ./js/background.js  2016-06-29 13:43:15.630344628 +0200
+++ userdata/Default/Extensions/bikioccmkafdpakkkcpdbppfkghcmihk/0.15.0_0/js/background.js    2016-06-29 14:06:29.530300934 +0200
@@ -47,8 +47,8 @@
         });
     });
 
-    var SERVER_URL = &#39;https://textsecure-service-staging.whispersystems.org&#39;;
-    var ATTACHMENT_SERVER_URL = &#39;https://whispersystems-textsecure-attachments-staging.s3.amazonaws.com&#39;;
+    var SERVER_URL = &#39;https://textsecure-service-ca.whispersystems.org:4433&#39;;
+    var ATTACHMENT_SERVER_URL = &#39;https://whispersystems-textsecure-attachments.s3.amazonaws.com&#39;;
     var messageReceiver;
     window.getSocketStatus = function() {
         if (messageReceiver) {
diff -ur ./js/expire.js userdata/Default/Extensions/bikioccmkafdpakkkcpdbppfkghcmihk/0.15.0_0/js/expire.js
--- ./js/expire.js      2016-06-29 13:43:15.630344628 +0200
+++ userdata/Default/Extensions/bikioccmkafdpakkkcpdbppfkghcmihk/0.15.0_0/js/expire.js2016-06-29 14:06:29.530300934 +0200
@@ -1,6 +1,6 @@
 ;(function() {
     &#39;use strict&#39;;
-    var BUILD_EXPIRATION = 0;
+    var BUILD_EXPIRATION = 1474492690000;
 
     window.extension = window.extension || {};
 
EOF
&lt;/pre&gt;

&lt;p&gt;The first part is changing the servers, and the second is updating
an expiration timestamp.  This timestamp need to be updated regularly.
It is set 90 days in the future by the build process (Gruntfile.js).
The value is seconds since 1970 times 1000, as far as I can tell.&lt;/p&gt;

&lt;p&gt;Based on a tip and good help from the #nuug IRC channel, I wrote a
script to launch Signal in Chromium.&lt;/p&gt;

&lt;pre&gt;
#!/bin/sh
cd $(dirname $0)
mkdir -p userdata
exec chromium \
  --proxy-server=&quot;socks://localhost:9050&quot; \
  --user-data-dir=`pwd`/userdata --load-and-launch-app=`pwd`
&lt;/pre&gt;

&lt;p&gt; The script start the app and configure Chromium to use the Tor
SOCKS5 proxy to make sure those controlling the Signal servers (today
Amazon and Whisper Systems) as well as those listening on the lines
will have a harder time location my laptop based on the Signal
connections if they use source IP address.&lt;/p&gt;

&lt;p&gt;When the script starts, one need to follow the instructions under
&quot;Standalone Registration&quot; in the CONTRIBUTING.md file in the git
repository.  I right clicked on the Signal window to get up the
Chromium debugging tool, visited the &#39;Console&#39; tab and wrote
&#39;extension.install(&quot;standalone&quot;)&#39; on the console prompt to get the
registration form.  Then I entered by land line phone number and
pressed &#39;Call&#39;.  5 seconds later the phone rang and a robot voice
repeated the verification code three times.  After entering the number
into the verification code field in the form, I could start using
Signal from my laptop.

&lt;p&gt;As far as I can tell, The Signal app will leak who is talking to
whom and thus who know who to those controlling the central server,
but such leakage is hard to avoid with a centrally controlled server
setup.  It is something to keep in mind when using Signal - the
content of your chats are harder to intercept, but the meta data
exposing your contact network is available to people you do not know.
So better than many options, but not great.  And sadly the usage is
connected to my land line, thus allowing those controlling the server
to associate it to my home and person.  I would prefer it if only
those I knew could tell who I was on Signal.  There are options
avoiding such information leakage, but most of my friends are not
using them, so I am stuck with Signal for now.&lt;/p&gt;
</description>
        </item>
        
        <item>
                <title>The new &quot;best&quot; multimedia player in Debian?</title>
                <link>http://people.skolelinux.org/pere/blog/The_new__best__multimedia_player_in_Debian_.html</link>
                <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/The_new__best__multimedia_player_in_Debian_.html</guid>
                <pubDate>Mon, 6 Jun 2016 12:50:00 +0200</pubDate>
                <description>&lt;p&gt;When I set out a few weeks ago to figure out
&lt;a href=&quot;http://people.skolelinux.org/pere/blog/What_is_the_best_multimedia_player_in_Debian_.html&quot;&gt;which
multimedia player in Debian claimed to support most file formats /
MIME types&lt;/a&gt;, I was a bit surprised how varied the sets of MIME types
the various players claimed support for.  The range was from 55 to 130
MIME types.  I suspect most media formats are supported by all
players, but this is not really reflected in the MimeTypes values in
their desktop files.  There are probably also some bogus MIME types
listed, but it is hard to identify which one this is.&lt;/p&gt;

&lt;p&gt;Anyway, in the mean time I got in touch with upstream for some of
the players suggesting to add more MIME types to their desktop files,
and decided to spend some time myself improving the situation for my
favorite media player VLC.  The fixes for VLC entered Debian unstable
yesterday. The complete list of MIME types can be seen on the
&lt;a href=&quot;https://wiki.debian.org/DebianMultimedia/PlayerSupport&quot;&gt;Multimedia
player MIME type support status&lt;/a&gt; Debian wiki page.&lt;/p&gt;

&lt;p&gt;The new &quot;best&quot; multimedia player in Debian?  It is VLC, followed by
totem, parole, kplayer, gnome-mpv, mpv, smplayer, mplayer-gui and
kmplayer.  I am sure some of the other players desktop files support
several of the formats currently listed as working only with vlc,
toten and parole.&lt;/p&gt;

&lt;p&gt;A sad observation is that only 14 MIME types are listed as
supported by all the tested multimedia players in Debian in their
desktop files: audio/mpeg, audio/vnd.rn-realaudio, audio/x-mpegurl,
audio/x-ms-wma, audio/x-scpls, audio/x-wav, video/mp4, video/mpeg,
video/quicktime, video/vnd.rn-realvideo, video/x-matroska,
video/x-ms-asf, video/x-ms-wmv and video/x-msvideo.  Personally I find
it sad that video/ogg and video/webm is not supported by all the media
players in Debian.  As far as I can tell, all of them can handle both
formats.&lt;/p&gt;
</description>
        </item>
        
        <item>
                <title>A program should be able to open its own files on Linux</title>
                <link>http://people.skolelinux.org/pere/blog/A_program_should_be_able_to_open_its_own_files_on_Linux.html</link>
                <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/A_program_should_be_able_to_open_its_own_files_on_Linux.html</guid>
                <pubDate>Sun, 5 Jun 2016 08:30:00 +0200</pubDate>
                <description>&lt;p&gt;Many years ago, when koffice was fresh and with few users, I
decided to test its presentation tool when making the slides for a
talk I was giving for NUUG on Japhar, a free Java virtual machine.  I
wrote the first draft of the slides, saved the result and went to bed
the day before I would give the talk.  The next day I took a plane to
the location where the meeting should take place, and on the plane I
started up koffice again to polish the talk a bit, only to discover
that kpresenter refused to load its own data file.  I cursed a bit and
started making the slides again from memory, to have something to
present when I arrived.  I tested that the saved files could be
loaded, and the day seemed to be rescued.  I continued to polish the
slides until I suddenly discovered that the saved file could no longer
be loaded into kpresenter.  In the end I had to rewrite the slides
three times, condensing the content until the talk became shorter and
shorter.  After the talk I was able to pinpoint the problem &amp;ndash;
kpresenter wrote inline images in a way itself could not understand.
Eventually that bug was fixed and kpresenter ended up being a great
program to make slides.  The point I&#39;m trying to make is that we
expect a program to be able to load its own data files, and it is
embarrassing to its developers if it can&#39;t.&lt;/p&gt;

&lt;p&gt;Did you ever experience a program failing to load its own data
files from the desktop file browser?  It is not a uncommon problem.  A
while back I discovered that the screencast recorder
gtk-recordmydesktop would save an Ogg Theora video file the KDE file
browser would refuse to open.  No video player claimed to understand
such file.  I tracked down the cause being &lt;tt&gt;file --mime-type&lt;/tt&gt;
returning the application/ogg MIME type, which no video player I had
installed listed as a MIME type they would understand.  I asked for
&lt;a href=&quot;http://bugs.gw.com/view.php?id=382&quot;&gt;file to change its
behavour&lt;/a&gt; and use the MIME type video/ogg instead.  I also asked
several video players to add video/ogg to their desktop files, to give
the file browser an idea what to do about Ogg Theora files.  After a
while, the desktop file browsers in Debian started to handle the
output from gtk-recordmydesktop properly.&lt;/p&gt;

&lt;p&gt;But history repeats itself.  A few days ago I tested the music
system Rosegarden again, and I discovered that the KDE and xfce file
browsers did not know what to do with the Rosegarden project files
(*.rg).  I&#39;ve reported &lt;a href=&quot;http://bugs.debian.org/825993&quot;&gt;the
rosegarden problem to BTS&lt;/a&gt; and a fix is commited to git and will be
included in the next upload.  To increase the chance of me remembering
how to fix the problem next time some program fail to load its files
from the file browser, here are some notes on how to fix it.&lt;/p&gt;

&lt;p&gt;The file browsers in Debian in general operates on MIME types.
There are two sources for the MIME type of a given file.  The output from
&lt;tt&gt;file --mime-type&lt;/tt&gt; mentioned above, and the content of the
shared MIME type registry (under /usr/share/mime/).  The file MIME
type is mapped to programs supporting the MIME type, and this
information is collected from
&lt;a href=&quot;https://www.freedesktop.org/wiki/Specifications/desktop-entry-spec/&quot;&gt;the
desktop files&lt;/a&gt; available in /usr/share/applications/.  If there is
one desktop file claiming support for the MIME type of the file, it is
activated when asking to open a given file.  If there are more, one
can normally select which one to use by right-clicking on the file and
selecting the wanted one using &#39;Open with&#39; or similar.  In general
this work well.  But it depend on each program picking a good MIME
type (preferably
&lt;a href=&quot;http://www.iana.org/assignments/media-types/media-types.xhtml&quot;&gt;a
MIME type registered with IANA&lt;/a&gt;), file and/or the shared MIME
registry recognizing the file and the desktop file to list the MIME
type in its list of supported MIME types.&lt;/p&gt;

&lt;p&gt;The &lt;tt&gt;/usr/share/mime/packages/rosegarden.xml&lt;/tt&gt; entry for
&lt;a href=&quot;http://www.freedesktop.org/wiki/Specifications/shared-mime-info-spec&quot;&gt;the
Shared MIME database&lt;/a&gt; look like this:&lt;/p&gt;

&lt;p&gt;&lt;blockquote&gt;&lt;pre&gt;
&amp;lt;?xml version=&quot;1.0&quot; encoding=&quot;UTF-8&quot;?&amp;gt;
&amp;lt;mime-info xmlns=&quot;http://www.freedesktop.org/standards/shared-mime-info&quot;&amp;gt;
  &amp;lt;mime-type type=&quot;audio/x-rosegarden&quot;&amp;gt;
    &amp;lt;sub-class-of type=&quot;application/x-gzip&quot;/&amp;gt;
    &amp;lt;comment&amp;gt;Rosegarden project file&amp;lt;/comment&amp;gt;
    &amp;lt;glob pattern=&quot;*.rg&quot;/&amp;gt;
  &amp;lt;/mime-type&amp;gt;
&amp;lt;/mime-info&amp;gt;
&lt;/pre&gt;&lt;/blockquote&gt;&lt;/p&gt;

&lt;p&gt;This states that audio/x-rosegarden is a kind of application/x-gzip
(it is a gzipped XML file).  Note, it is much better to use an
official MIME type registered with IANA than it is to make up ones own
unofficial ones like the x-rosegarden type used by rosegarden.&lt;/p&gt;

&lt;p&gt;The desktop file of the rosegarden program failed to list
audio/x-rosegarden in its list of supported MIME types, causing the
file browsers to have no idea what to do with *.rg files:&lt;/p&gt;

&lt;p&gt;&lt;blockquote&gt;&lt;pre&gt;
% grep Mime /usr/share/applications/rosegarden.desktop
MimeType=audio/x-rosegarden-composition;audio/x-rosegarden-device;audio/x-rosegarden-project;audio/x-rosegarden-template;audio/midi;
X-KDE-NativeMimeType=audio/x-rosegarden-composition
%
&lt;/pre&gt;&lt;/blockquote&gt;&lt;/p&gt;

&lt;p&gt;The fix was to add &quot;audio/x-rosegarden;&quot; at the end of the
MimeType= line.&lt;/p&gt;

&lt;p&gt;If you run into a file which fail to open the correct program when
selected from the file browser, please check out the output from
&lt;tt&gt;file --mime-type&lt;/tt&gt; for the file, ensure the file ending and
MIME type is registered somewhere under /usr/share/mime/ and check
that some desktop file under /usr/share/applications/ is claiming
support for this MIME type.  If not, please report a bug to have it
fixed. :)&lt;/p&gt;
</description>
        </item>
        
        <item>
                <title>Tor - from its creators mouth 11 years ago</title>
                <link>http://people.skolelinux.org/pere/blog/Tor___from_its_creators_mouth_11_years_ago.html</link>
                <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Tor___from_its_creators_mouth_11_years_ago.html</guid>
                <pubDate>Sat, 28 May 2016 14:20:00 +0200</pubDate>
                <description>&lt;p&gt;A little more than 11 years ago, one of the creators of Tor, and
the current President of &lt;a href=&quot;https://www.torproject.org/&quot;&gt;the Tor
project&lt;/a&gt;, Roger Dingledine, gave a talk for the members of the
&lt;a href=&quot;http://www.nuug.no/&quot;&gt;Norwegian Unix User group&lt;/a&gt; (NUUG).  A
video of the talk was recorded, and today, thanks to the great help
from David Noble, I finally was able to publish the video of the talk
on Frikanalen, the Norwegian open channel TV station where NUUG
currently publishes its talks.  You can
&lt;a href=&quot;http://frikanalen.no/se&quot;&gt;watch the live stream using a web
browser&lt;/a&gt; with WebM support, or check out the recording on the video
on demand page for the talk
&quot;&lt;a href=&quot;http://beta.frikanalen.no/video/625599&quot;&gt;Tor: Anonymous
communication for the US Department of Defence...and you.&lt;/a&gt;&quot;.&lt;/p&gt;

&lt;p&gt;Here is the video included for those of you using browsers with
HTML video and Ogg Theora support:&lt;/p&gt;

&lt;p&gt;&lt;video width=&quot;70%&quot; poster=&quot;http://simula.gunkies.org/media/625599/large_thumb/20050421-tor-frikanalen.jpg&quot; controls&gt;
  &lt;source src=&quot;http://simula.gunkies.org/media/625599/theora/20050421-tor-frikanalen.ogv&quot; type=&quot;video/ogg&quot;/&gt;
&lt;/video&gt;&lt;/p&gt;

&lt;p&gt;I guess the gist of the talk can be summarised quite simply: If you
want to help the military in USA (and everyone else), use Tor. :)&lt;/p&gt;
</description>
        </item>
        
        <item>
                <title>Isenkram with PackageKit support - new version 0.23 available in Debian unstable</title>
                <link>http://people.skolelinux.org/pere/blog/Isenkram_with_PackageKit_support___new_version_0_23_available_in_Debian_unstable.html</link>
                <guid isPermaLink="true">http://people.skolelinux.org/pere/blog/Isenkram_with_PackageKit_support___new_version_0_23_available_in_Debian_unstable.html</guid>
                <pubDate>Wed, 25 May 2016 10:20:00 +0200</pubDate>
                <description>&lt;p&gt;&lt;a href=&quot;https://tracker.debian.org/pkg/isenkram&quot;&gt;The isenkram
system&lt;/a&gt; is a user-focused solution in Debian for handling hardware
related packages.  The idea is to have a database of mappings between
hardware and packages, and pop up a dialog suggesting for the user to
install the packages to use a given hardware dongle.  Some use cases
are when you insert a Yubikey, it proposes to install the software
needed to control it; when you insert a braille reader list it
proposes to install the packages needed to send text to the reader;
and when you insert a ColorHug screen calibrator it suggests to
install the driver for it.  The system work well, and even have a few
command line tools to install firmware packages and packages for the
hardware already in the machine (as opposed to hotpluggable hardware).&lt;/p&gt;

&lt;p&gt;The system was initially written using aptdaemon, because I found
good documentation and example code on how to use it.  But aptdaemon
is going away and is generally being replaced by
&lt;a href=&quot;http://www.freedesktop.org/software/PackageKit/&quot;&gt;PackageKit&lt;/a&gt;,
so Isenkram needed a rewrite.  And today, thanks to the great patch
from my college Sunil Mohan Adapa in the FreedomBox project, the
rewrite finally took place.  I&#39;ve just uploaded a new version of
Isenkram into Debian Unstable with the patch included, and the default
for the background daemon is now to use PackageKit.  To check it out,
install the &lt;tt&gt;isenkram&lt;/tt&gt; package and insert some hardware dongle
and see if it is recognised.&lt;/p&gt;

&lt;p&gt;If you want to know what kind of packages isenkram would propose for
the machine it is running on, you can check out the isenkram-lookup
program.  This is what it look like on a Thinkpad X230:&lt;/p&gt;

&lt;p&gt;&lt;blockquote&gt;&lt;pre&gt;
% isenkram-lookup 
bluez
cheese
fprintd
fprintd-demo
gkrellm-thinkbat
hdapsd
libpam-fprintd
pidgin-blinklight
thinkfan
tleds
tp-smapi-dkms
tp-smapi-source
tpb
%p
&lt;/pre&gt;&lt;/blockquote&gt;&lt;/p&gt;

&lt;p&gt;The hardware mappings come from several places.  The preferred way
is for packages to announce their hardware support using
&lt;a href=&quot;https://www.freedesktop.org/software/appstream/docs/&quot;&gt;the
cross distribution appstream system&lt;/a&gt;.
See
&lt;a href=&quot;http://people.skolelinux.org/pere/blog/tags/isenkram/&quot;&gt;previous
blog posts about isenkram&lt;/a&gt; to learn how to do that.&lt;/p&gt;
</description>
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        </channel>
</rss>