TronProg: Programming and Computers

This can be seen as a sort of follow-up of my previous post, Eclipse internal Web Browser in Ubuntu Lucid: after installing Kubuntu Precise Pangolin 12.04 the internal browser of Eclipse stopped working. In particular, when using Mylyn Gerrit connector (relying on OpenID authentication, which requires the eclipse internal browser) I got this error

org.eclipse.swt.SWTException: Failed to execute runnable (org.eclipse.swt.SWTError: No more handles [Unknown Mozilla path (MOZILLA_FIVE_HOME not set)])

sudo apt-get install libwebkitgtk-1.0-0

Pubblicato da betto a 9:02 PM 7 commenti

Etichette: eclipse, kubuntu, precise

After I switched to Kubuntu Natty 11.04, my microphone stopped working (especially in Skype). I tried to adjust the microphone settings in Phonon System Settings, but, besides having too many devices to choose from, that settings dialog seems to have a bug which prevents the preferences to being saved. Not to mention that there is no way to test the input device from that setting dialog!

Luckily, in that bug report I also found the solution to have microphone work!

The solution consists in installing the package pavucontrol, which provides a comfortable PulseAudio Volume Control dialog, which also gives you immediate feedback to see whether the microphone is working, and reduces the number of devices to choose from!

After you installed that package, Skype options dialog presents a button to open that volume control dialog


If you click the button you'll get the pavucontrol dialog, and in "Input Devices" tab you can choose the input device from the list and instantly check whether that's the right device: just speak in the microphone, and see whether the horizontal bar moves while you're speaking.


That's all! Now you're microphone is set correctly. :)

Pubblicato da betto a 11:43 AM 19 commenti

Etichette: audio, kubuntu, natty, skype, ubuntu

I was experiencing problems with the microphone (in Skype) in Kubuntu Maverick 10.10: no input was received by the microphone, either in Skype or using the arecord. The soundcard is an

Intel [HDA Intel], device 0: AD198x Analog [AD198x Analog]

Pubblicato da betto a 4:45 PM 0 commenti

Etichette: audio, kubuntu, linux

I've always recompiled Linux kernel on all my Linux installations, starting from the kernel sources of the Ubuntu repositories. Then I've heard about the famous 200 lines kernel patch, that I wanted to try, but it doesn't seem to apply to ubuntu linux sources (or at least I had this impression), and I didn't want to try the alternatives.

Then I stumbled upon this nice article about using KernelCheck (which I didn't know) to compile the linux kernel (not from the ubuntu repositories):

a graphical user interface program designed to make the kernel-compiling process as easy as the click of a button. KernelCheck will fetch the latest information from http://www.kernel.org, which hosts the source packages for the Linux kernel, and ask the user which one they would like to compile into a .deb package (with the option of installing the kernel after the compilation).

• NOT to select the reconfiguration of X server
• NOT to install the nvidia driver
• to select "apply custom patch to the kernel" (if you want to try the 200 lines patch)
• I prefer not to install the kernel package after compilation: I'll do that myself
  

Pubblicato da betto a 12:50 PM 3 commenti

Etichette: kernel, kubuntu, linux, nvidia, ubuntu

Lately I started to try to develop applications for the Nokia N900, and the Maemo platform uses my beloved framework Qt :)

In particular, Nokia started to develop the Qt-Mobility Framework. Quoting from their white paper:

The Qt Mobility Project presents a collection of related software frameworks and interfaces. The objective being to deliver new Qt APIs for mobile application developers. Using these new APIs, developers will be able to create cross-platform applications targeting Maemo, Symbian and other platforms. This suite of features also has components that will be desirable to all users, not just those with mobile devices, so Mobility has advantages even for the desktop user.

sudo apt-get install libasound2-dev libbluetooth-dev libgstreamer0.10-dev libgstreamer-plugins-base0.10-dev network-manager-dev libxv-dev gstreamer-tools gstreamer0.10-plugins-base gstreamer0.10-ffmpeg w32codecs ubuntu-restricted-extras gstreamer0.10-plugins-good freeglut3-dev

git clone git://gitorious.org/qt-mobility/qt-mobility.git

• cd ~/build/qt-mobility/qt-4.6.3
• PATH=~/usr/local/Trolltech/qtsdk-2010.03/qt/bin:$PATH ~/install/qt-mobility/configure -examples -prefix ~/usr/local/Trolltech/qt-mobility> output.txt

• make
• make install

• install -m 644 -p /home/bettini/build/qt-mobility/qt-4.6.3/features/mobility.prf /home/bettini/usr/local/Trolltech/qtsdk-2010.03/qt/mkspecs/features/
• install -m 644 -p /home/bettini/build/qt-mobility/qt-4.6.3/features/mobilityconfig.prf /home/bettini/usr/local/Trolltech/qtsdk-2010.03/qt/mkspecs/features/
  

• ~/usr/local/Trolltech/qt-mobility/bin/player
• ~/usr/local/Trolltech/qt-mobility/bin/weatherinfo_with_location

QT += core gui

TARGET = myvideowidget
TEMPLATE = app


SOURCES += main.cpp\
 mainwindow.cpp

HEADERS += mainwindow.h

CONFIG += mobility
MOBILITY = multimedia

#ifndef MAINWINDOW_H
#define MAINWINDOW_H

#include <QMainWindow>

class QVideoWidget;
class QMediaPlayer;

class MainWindow : public QMainWindow
{
 Q_OBJECT

public:
 explicit MainWindow(QWidget *parent = 0);

private:
 QVideoWidget *videoWidget;
 QMediaPlayer *player;
};

#endif // MAINWINDOW_H

#include <QMediaPlayer>
#include <QVideoWidget>
#include <QTextEdit>

#include "mainwindow.h"

MainWindow::MainWindow(QWidget *parent) :
 QMainWindow(parent)
{
 videoWidget = new QVideoWidget(this);

 setCentralWidget(videoWidget);
}

#include <QtGui/QApplication>
#include "mainwindow.h"

int main(int argc, char *argv[])
{
 QApplication a(argc, argv);
 MainWindow w;
 w.show();
 return a.exec();
}

• ~/usr/local/Trolltech/qtsdk-2010.03/qt/bin/qmake myvideowidget.pro

• g++ -c -pipe -O2 -Wall -W -D_REENTRANT -DQT_NO_DEBUG -DQT_OPENGL_LIB -DQT_GUI_LIB -DQT_NETWORK_LIB -DQT_CORE_LIB -DQT_SHARED -I../../../../usr/local/Trolltech/qtsdk-2010.03/qt/mkspecs/linux-g++ -I../../myvideowidget -I../../../../usr/local/Trolltech/qtsdk-2010.03/qt/include/QtCore -I../../../../usr/local/Trolltech/qtsdk-2010.03/qt/include/QtNetwork -I../../../../usr/local/Trolltech/qtsdk-2010.03/qt/include/QtGui -I../../../../usr/local/Trolltech/qtsdk-2010.03/qt/include/QtOpenGL -I../../../../usr/local/Trolltech/qtsdk-2010.03/qt/include -I/home/bettini/usr/local/Trolltech/qtsdk-2010.03/qt/include/QtMultimediaKit -I../../../../usr/local/Trolltech/qt-mobility/include -I../../../../usr/local/Trolltech/qt-mobility/include/QtMultimediaKit -I/usr/X11R6/include -I. -I../../myvideowidget -I. -o mainwindow.o ../../myvideowidget/mainwindow.cpp
• g++ -Wl,-O1 -Wl,-rpath,/home/bettini/usr/local/Trolltech/qtsdk-2010.03/qt/lib -Wl,-rpath,/home/bettini/usr/local/Trolltech/qt-mobility/lib -o myvideowidget main.o mainwindow.o moc_mainwindow.o -L/home/bettini/usr/local/Trolltech/qtsdk-2010.03/qt/lib -L/usr/X11R6/lib -L/home/bettini/usr/local/Trolltech/qt-mobility/lib -lQtMultimediaKit -lQtOpenGL -L/home/bettini/usr/local/Trolltech/qtsdk-2010.03/qt/lib -L/usr/X11R6/lib -lQtGui -lQtNetwork -lQtCore -lGLU -lGL -lpthread

Pubblicato da betto a 11:05 AM 2 commenti

Etichette: kubuntu, maemo, qt, qt-mobility, ubuntu

In a previous post I blogged about sucessfully installing this Huawei E1692 Internet device in Ubuntu Jaunty. Now that I switched to Kubuntu Karmic I found out that this device was not recognized any more.

Fortunately, this was a known issue, and I found this blog post which summarizes the solution to use this device also in Ubuntu Karmic.

I followed the instructions, however, the device still didn't show up (in particular, it wasn't mounted as an external device so that I could run the installation procedure). Probably it's a problem of Kubuntu and not Ubuntu (and I don't have Ubuntu version of Karmic, but only the Kubuntu one), so I cannot tell for sure.

However, you only need to perform some manual steps and it works in Kubuntu as well.

First, you need to follow the instructions found in this blog post anyway.

First of all, by running dmesg after inserting the device you should see something like the following lines which, at least, tells you that the device is recognized (though not mounted):

[ 664.188996] usb-storage: device found at 6 
[ 664.188998] usb-storage: waiting for device to settle before scanning 
[ 664.189997] scsi9 : SCSI emulation for USB Mass Storage devices 
[ 664.190571] usb-storage: device found at 6 
[ 664.190573] usb-storage: waiting for device to settle before scanning 
[ 669.189727] usb-storage: device scan complete 
[ 669.191577] scsi 8:0:0:0: CD-ROM HUAWEI Mass Storage 2.31 PQ: 0 ANSI: 2 
[ 669.191585] usb-storage: device scan complete 
[ 669.194267] scsi 9:0:0:0: Direct-Access HUAWEI SD Storage 2.31 PQ: 0 ANSI: 2 
[ 669.212737] sr1: scsi-1 drive 
[ 669.213052] sr 8:0:0:0: Attached scsi CD-ROM sr1 
[ 669.213215] sr 8:0:0:0: Attached scsi generic sg2 type 5 
[ 669.214044] sd 9:0:0:0: Attached scsi generic sg3 type 0 
[ 669.235684] sd 9:0:0:0: [sdb] Attached SCSI removable disk

sudo mount -t iso9660 /dev/sr1 /mnt/

sudo /mnt/install_linux

Pubblicato da betto a 2:13 PM 4 commenti

Etichette: karmic, kubuntu, linux, mobile, modem

I finally had a working version of PDT (Php eclipse plugin) and XDebug, so that I can finally debug, not only php script, but also php web sites! :-)

This blog post helped me a lot, but I must also admit that pdt people did a wonderful job, and now everything seems to work out of the box!

First of all I relied on the pdt all in one version (i.e., eclipse together with all the requested plugins and the pdt plugin), that can be found at http://www.eclipse.org/pdt/downloads.

However, you also need to install xdebug and (k)ubuntu already has a package for this, so you just need to type

apt-get install php5-xdebug

Now just check the path of the xdebug.so library file, in my case it is

/usr/lib/php5/20060613+lfs/xdebug.so

then you'll need to add some parts in the php.ini configuration file, so you need to add at the end of your /etc/php5/apache2/php.ini these lines (use the path of xdebug.so above):

; XDebug
zend_extension="/usr/lib/php5/20060613+lfs/xdebug.so"
xdebug.remote_enable=true
xdebug.remote_host="127.0.0.1" ; if debugging on remote server,
 ; put client IP here

Pubblicato da betto a 6:33 PM 0 commenti

Etichette: eclipse, kubuntu, linux, pdt, xdebug

Finally, I managed to connect to the Internet with my Nokia 6630 in Linux Kubuntu; it's not that I had troubles before: it's just that I had never had to connect with the cellphone, and I must admit that I quite appreciated that it was really easy and straightforward to this :-)

Actually, first I had tried with the bluetooth way and thanks to many documentation found on the web, I succeeded, though the procedure might not be trivial. However, in that case, I noticed that the connection was not reliable and not very fast. So I decided to buy a (quite expensive for what it does) USB cable (it's just a usb cable... why does it cost 20 euros?!).

Well, with USB the procedure is even more trivial: you just connect it and you'll see that dmesg happily reports this:

[ 149.162045] usb 3-2: new full speed USB device using uhci_hcd and address 2
[ 149.207194] usb 3-2: configuration #1 chosen from 1 choice
[ 149.461122] cdc_acm 3-2:1.8: ttyACM0: USB ACM device
[ 149.463589] usbcore: registered new interface driver cdc_acm
[ 149.463594] /build/buildd/linux-2.6.24/drivers/usb/class/cdc-acm.c: v0.25:USB Abstract Control Model driver for USB modems and ISDN adapters

ll /dev/ttyACM0
crw-rw---- 1 root dialout 166, 0 2008年12月24日 17:28 /dev/ttyACM0

AT+cgdcont=,"ip","ibox.tim.it"

Pubblicato da betto a 10:34 AM 0 commenti

Etichette: kubuntu, linux, nokia

I tried Compiz on a desktop computer, but this made the system pretty slow, so I removed it with synaptic... after a restart, all the windows of the KDE desktop were shown without a frame (thus it was pretty useless). This seems to be a known bug in (k)ubuntu, but the solution

sudo aptitude reinstall kwin

find ~/ -name "*compiz*" -exec rm -rf {} \;

Pubblicato da betto a 1:43 PM 1 commenti

Etichette: kde, kubuntu

I had struggled in the past already with a Xerox Phaser 4500; now a new printer, a Xerox Phaser 4510 was brought at work and so I was already worried about its installation with cups, in kubuntu, since no driver is provided by default by cups.

However, this time was quite easy, since the Xerox site provides some new drivers that can be downloaded freely here.

You just need to untar the package and use the right .ppd file, and in my case it is xrx4510dt.ppd.

I installed this printer with the CUPS web interface (with the configuration procedure of KDE it failed to correctly set this printer, don't know why), and when you come to select the model you provide the above ppd file.

Everything then worked like a charm!

Pubblicato da betto a 11:21 AM 4 commenti

Etichette: cups, kubuntu, linux, xerox

My new desktop at work is a Dell Optiplex 330, where Linux made its way from the very beginning. I started with my beloved Kubuntu, and then tried also Sabayon. With both distributions I soon noticed a boring bug: the computer does not reboot. After terminating the reboot operations the system just hangs and the computer does not reboot. Fortunately, this is a known bug for many computers, and the solution was quite easy: add the option reboot=b to the kernel line in the grub configuration list. This worked for me both for Kubuntu and Sabayon :-)

Pubblicato da betto a 3:08 PM 4 commenti

Etichette: kubuntu, linux, sabayon

I usually use the computer with a permanent connection to the Internet, so I hadn't noticed this problem. But lately, since I'm using also my laptop off line I started to struggle with this problem: when I use konqueror to connect to a local site, I get this error:

An error occurred while loading http://localhost:
Could not connect to host http://localhost.

Pubblicato da betto a 2:19 PM 0 commenti

Etichette: kubuntu, linux

The time has come I have to return this laptop to my Department, a Sony Vaio VGN-S5VP/B.

I can't say I'm sorry since I didn't like this laptop too much... probably what made me quite biased was the bad story concerning the extended battery (I talked about this issue in this blog).

However, before returning it, a few months ago, I tried to install on this laptop also Kubuntu (I was already using Debian).

The installation was quite smooth and everything seems to work (also things that were not working in Debian, or were quite hard to configure).

You can find details about this installation here: http://www.lorenzobettini.it/linux/kubuntu_vaio.

Pubblicato da betto a 8:36 PM 0 commenti

Etichette: kubuntu, laptop, sony vaio

I've been experienced for some weeks a crash problems with Eclipse on my Debian installation on my Desktop... I use Debian (and Gentoo) on all my computers (3 desktops and 1 laptop), and this was the only computer showing this problem... unfortunately I haven't been able to solve the problem and so I resorted to reinstall the distribution.

I had tried kubuntu a year ago, and I didn't like it... but I thought I could give it another try, and so, instead of re-installing Debian (I'm using Debian on the other computers after all so I won't miss it), and installed a kubuntu edgy 6.10. Since I definitely don't like Gnome (I never did, and probably never will ;-) while I've always loved the pleasant environment provided by KDE, kubuntu was the only choice, instead of ubuntu.

My first impressions were definitely good: the installation consists of only few steps (although grub by default wants to install itself on the mbr, while I didn't want to touch the mbr, since I'm using Gentoo's installation grub, and it wasn't clear in the beginning how to avoid this) and it's quite smooth.

After the installation I was surprised by the desktop and menus that are quite clean, with only the essential programs; actually I was a little bit disappointed by the lacking of programs I'm used to, such as, e.g., the program for resizing the screen (although there's a similar program in System Settings). Concerning the System Settings program, this seems to replace the standard KDE Control Center, but it lacks some voices such as "themes". You can still call the good ol' KDE Control Center by the terminal, though.

I soon installed the good ol' Synaptic package manager, since I wasn't comfortable with Adept package manager, since it provides too few functionalities and packages (but probably it's more usable for the first time users, so praise for it!). Adept is however very good for update checking and installation. It checks for updates in background and then notifies you if some updates are ready. Installing the updates is also very easy.



What I never liked about (k)ubuntu, and I don't think I ever will, is the fact that you're forced to use sudo, since root shell is disabled... I don't think this enhances security and it's less error prone, but that's just my opinion... In fact, I always use sudo -s that opens a root shell ;-)

Another really great surprise is that, few weeks ago, the adept manager not only notified me about available updates, but also about the update of the whole kubuntu distribution itself!


It offered me to install the update (the new Kubuntu 7.04, codenamed Feisty Fawn), and I didn't refuse :-)


This update takes some time but goes on smoothly


and after the downloading, the installation of the update starts and when it's finished you can simply reboot into your new system!


I then enjoyed my new kubuntu system! I think I'll keep on using kubuntu (of course, together with debian and gentoo :-) since it really looks like a very good distribution (standing on the shoulders of the giants... but it stands very well!)

Pubblicato da betto a 9:44 PM 6 commenti

Etichette: debian, kubuntu, linux