Mad Linux

Double UTF-8

2011-11-23T14:34:00.000-08:00

Have you ever encountered an issue with national charset being double encoded by UTF-8?

On linux it can be seen as strange capital "A" with unusual diacritics within the filenames.

Example od such weird behavior is:

which is in hex actualy:

This is hex code for the double encoded text:

50 c4 b9 c2 99 c4 82 c2 ad 6c 69 c4 b9 c4 84 20 c4 b9 c5 be

6c 75 c4 b9 c4 bd 6f 75 c3 84 c2 8d 6b c4 82 cb 9d 20 6b c4

b9 c5 bb c4 b9 c2 88 20 c4 82 c5 9f 70 c3 84 c2 9b 6c 20 64

c4 82 c4 84 62 65 6c 73 6b c4 82 c5 a0 20 c4 82 c5 82 64 79

This is the correct utf-8 encoded text:

50 c5 99 c3 ad 6c 69 c5 a1 20 c5 be 6c 75 c5 a5 6f 75 c4

8d 6b c3 bd 20 6b c5 af c5 88 20 c3 ba 70 c4 9b 6c 20 64 c3

a1 62 65 6c 73 6b c3 a9 20 c3 b3 64 79

The reason for that is rather simple when the file was copied it already was in UTF-8 by the system thought that it is 8-bit encoding and thus recoding it again into UTF-8 second time.

The way to remove it is simple:

recode -f UTF-8..ISO_8859-1

or

convmv -f UTF-8 -t ISO_8859-1 *

Unfortunately the second variant does not rename directories, while the first can be used inside a script that does the tash bottom up (from file tree perspective). It could look like:

find dir -printf "%d %p" | sort -n -r | while read DEPTH FN; do
ON=$(basename "$FN")
NN=$(echo "$ON" | recode -f UTF-8..ISO_8859-1)
DN=$(dirname "$FN")
if [ "x$ON" != "x$NN" ]; then
mv "$FN" "$DN/$NN"
fi
done

Screen Capture tool (freeware)

2009-10-15T04:10:00.000-07:00

I case that you have to create some screenshot tour, then this one is a must!

Homepage
http://picpick.wiziple.net/

git for web

2009-10-06T22:45:00.000-07:00

To save you google search clicks. I have a hint for those that tried to use dumb apache as a backend for git repository. The issue is warning that HEAD does not point to valid info/ref file. This can be read from apache log. This is a listing file as mentioned on web that has to be updated to let git download content from server that does not speak git protocol.

Good to know, isn't it?

The key is to run following command regularly on the hub apache server:
git-update-server-info

The pull or clone works correctly. One bonus hint, when your server does not have valid certificate chain or has a private CA that was not yet included into your ca-chain in /etc yet. Then use GIT_SSL_NO_VERIFY=1 as prefix of any command or set it as exported into environment.

"make menuconfig"

2009-08-28T00:06:00.000-07:00

Have you ever been configuring linux kernel? All these deps and menu options, etc. How is the process done? There are some things in linux/scripts/kconfig directory, couple of files used:

menu config
- mconf.c
- zconf.tab.c
- conf.c

config
- conf.c
- zconf.tab.c

zconf.* are yacc grammar for conf file

Remote keyboard alternative

2009-08-27T12:24:00.000-07:00

Have you ever needed to control remote computer as if it was right inside your room? KVM is an option, but what if you cannot connect easily. Then KVM over IP is an alternative, but not the cheapest one. What if you need usb flash or sound connected... it starts getting more complex. Then USB-IP could be the best tip for your application giving access to any device connected to your local machine remotely. See at http://usbip.sourceforge.net/

Quick resize of images for windows

2009-08-19T02:33:00.000-07:00

If you need resize large number of pictures/photos.

Then http://www.rw-designer.com/picture-resize could be an option.

Cross ref for scripts

2009-08-19T02:13:00.000-07:00

When ever needed kind of cross references for scripts which uses which.

#!/bin/bash

FILS=$(ls -1 | egrep "(\.sh|\.pl)$"| while read JMN; do
if [ -f "$JMN" ]; then
echo "$JMN"
fi
done)

for FI in $FILS; do
echo "$FI"
for FJ in $FILS; do
if [ "x$(grep $FJ $FI)" != "x" ]; then
echo " * $FJ"
fi
done
done

Android First Look - Map View

2009-08-18T02:55:00.000-07:00

Learn to code, Android without APIs is not more than virtual machine... Therefore always in eclipse choose Google API (atop of Android 1.5 now).

proxy-setup that works also with google maps
sample map application, place to start
another sample, worth trying

Snippets:

- for code itself:
...

import com.google.android.maps.MapActivity;
...

@Override
protected boolean isRouteDisplayed() {
// TODO Auto-generated method stub
return false;
}

- for manifest:
<uses-permission android:name="android.permission.ACCESS_COARSE_LOCATION">
</uses-permission>
<uses-permission android:name="android.permission.INTERNET">
</uses-permission>

- for layout:
<com.google.android.maps.MapView
android:id="@+id/mapview1"
android:layout_width="fill_parent"
android:layout_height="fill_parent"
android:enabled="true"
android:clickable="true"
android:apiKey="..." >

Shell exec rsync

2009-08-10T02:05:00.000-07:00

How to execute remotely rsync that has dependency on some library which is in other path

#!/bin/bash

BD=${HOME}/bin
LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/lib; export LD_LIBRARY_PATH

exec $BD/rsync-real $*

Drag and Drop in applet

2009-06-25T00:21:00.000-07:00

Have you ever thought of this requirement. Although I have heard and seen google wave demo. And the notice dnd images in that demo via GWT there is not much more that this on the web. Some independent sample would have been handy for that purpose.

Is there something like demo or tutorial.

Nuts and Bolts of WordML

2009-04-01T01:31:00.000-07:00

It seems that Microsoft is making some progress. That was partially ignored by community because of various reasons. Fortunately it is one step in long walk to get to better world?

Fortunately it is somehow usable. Especially when able to ignore some weird functionality and benefit from XML. To give you some clues that may help you. First one is just go on and try. One important thing that I read in O'Reily's sample chapter of nice book "Office 2003 XML" is do not try to understand everything! Just play a bit and do not be scared of many unknown tags.

Few things to try just reformat XML into some nice indented form, like Notepad++ (TextFX -> TextFX HTML Tidy -> Tidy: Reindent XML). It produces nicely readable code BUT it breaks things in there so you must make a copy. At this point I was wondering whether some web application would not help me editing somehow the document (DOM, OracleXML or others).

Another point is that Microsoft WordXML at least in Word 2003 is able to do so strange thing like marking XML as being in UTF-8 but actualy saving it as a ISO Latin1 maybe CP497. Therefore "recode lat1..utf-8" gets handy.

Lot of unexpected behaviour must have been cleaned in Office 2007 but it is not adopted so widely and therefore you should keep 2003 version for some period of time.

Another strange thing that I revealed and is somehow documented somewhere on msdn.microsoft.com that when making pages landscape and portrait you should know that you have to put for all sections into except the last otherwise you get one surplus page.

IPTV revisited

2009-02-09T23:50:00.000-08:00

There are tons of websites found when "google:iptv dvbstream getstream" but not many of them describe the miracle of unix-style setup of transponder forward in a clear way.

dvbstream -c 0 -f 11325000 -p h -s 24500 -udp -i 233.51.128.19 -r 1234 8192

vlc udp://@233.51.128.19:1234
or
progdvb iptv

Boot CD howto

2009-01-29T07:15:00.001-08:00

How to prepare bootable USB or CD in a hurry UBCD, to be done...

Time lapse photos with Camedia 2040Z

2009-01-29T07:13:00.000-08:00

This is just idea placeholder for how I made first attempt in Time Lapse video/photos. Strange setup of computer controlled Camedia. root access necessary... to be continued

Bluetooth game

2009-01-11T23:05:00.001-08:00

Have you ever tried to not get mad from your bunch of gadgets? The good way to smart use is synchronize, synchronize and synchronize (... and backup). Replicas are some kind of updated backup strategies. But it can become more and more difficult connecting these many devices. Good news is that there is some nice communication and personal things like USB, BlueTooth and WiFi.
All of them can help you with you WM device, Smart Phone, S60 (N95 8GB), Android and Eee... and many other to get connected.

From communication point of view you can benefit from transports (keep switched to your linux mode) rndis0 (usb WM sync) or pan0/bnep0 (BlueTooth GN, NAP, ... mode personal networks). But then also comes some other troubles like hidd replaced with DBUS aware bluetoothd, pand replaced with network.service...

I spent some time working with these SW and I'll keep you informed of what's up in that landscape. Although I thought that it is just plug and play I has shown that it is not...

Sajax Error for foreign languages

2009-01-11T23:01:00.000-08:00

I decided to use sajax for binding pages with back end of PHP. Unfortunately that handy script was made by English only speaker and he did never catched one weird bug that is in there. And therefore sajax.php does not receive correctly national UTF-8 chracters. But solution is simple, just replace encode() with encodeURIComponent().

Weird Javascript

2009-01-11T22:55:00.000-08:00

Just small hint that can help you when hacking JavaScript. Whenever you try to use Ajax, then some strange things may happen. For example page is unintentionally reloaded and return value from Ajax call is lost. When you do that locally you may not even notice that there was double submit.

And the way out... Watch server logs you will see double submit. And avoid it! How as easy as ...href="#" onClick="return yourAjaxFunction(123,'params');"... and of course yourAjaxFunction should return false. Another alternative is to use additional return false at the end of Javascript in onClick.

QoS and Linux documentation

2008-06-08T22:32:00.000-07:00

I have recently came across a need for creating some Traffic Control rules for a commercial project. I hoped that Linux has a stable and comprehensive documentation. But it turned into a race for any information. It seems that iproute2 package which contains tc tool is not yet well documented. If it is documented at all. I have never seen such a poor documentation for any of Linux parts. There are two parts missing first documentation of how it all works. Some studies exist but most of them are outdated papers or diving just into some parts of the QoS problem. And the second description of control of the QoS via the tc program. I tried hard to get any information and I plan to issue some own to help.

How avoid FFoxes inteference

2008-06-08T10:26:00.000-07:00

I think that a lot of linux users have tested recetly published FireFox version 3. It is cute little tool and ubelievably fast. I spent more than 4 hours trying. These two versions try to share $HOME/.mozilla directory. But it somehow crashes when ever you install incompatible plugins, such us google toolbar or google gears.

What could be the solution for it. Simply move it somewhere else... but it depends on HOME and home is not easy to change and not to break any other program. Way out? Change it as close to the real binary as possible... it is in /usr/lib/firefox/run-firefox.sh, at the end when the program binary is started simply put this HOME=$HOME/.ff2

On Ubuntu 8.04 it simply works... Just useful hint, don't forget to link ~/.beagle to ~/.ff2/.beagle