[ S O L V E D ] - Executable: plasma-desktop PID: Signal: Segmentation fault (11)

I was playing around with plasma-desktop the other day, creating new activities at the desktop, adding useful widgets activity related when suddenly it crashed!
A window opened with a filled in crash report. The process was plasma-desktop and the failure was number 11.

The Black screen appeared. All that was working at first sight was the mouse.
By pressing ALT+F2 I got the run program prompt at the very top of the screen, I typed "konsole" to open one, and then typed plasma-desktop.

After a second or two, everything came back to normality, for at least 1 more second, then it crashed again.





This was the output of "plasma-desktop" when run from the 'konsole'.

~$ plasma-desktop
QDBusConnection: session D-Bus connection created before QCoreApplication. Application may misbehave.                                                                         
QDBusConnection: session D-Bus connection created before QCoreApplication. Application may misbehave.                                                                         
Gtk-Message: Failed to load module "gtk-vector-screenshot"                                                                                                                    
QDBusObjectPath: invalid path ""
plasma-desktop(3963)/libplasma Plasma::isPluginVersionCompatible: unversioned plugin detected, may result in instability
plasma-desktop(3963)/libplasma Plasma::isPluginVersionCompatible: unversioned plugin detected, may result in instability
plasma-desktop(3963)/libplasma Plasma::isPluginVersionCompatible: unversioned plugin detected, may result in instability
plasma-desktop(3963)/libplasma Plasma::isPluginVersionCompatible: unversioned plugin detected, may result in instability
plasma-desktop(3963)/libplasma Plasma::isPluginVersionCompatible: unversioned plugin detected, may result in instability
plasma-desktop(3963)/libplasma Plasma::isPluginVersionCompatible: unversioned plugin detected, may result in instability
plasma-desktop(3963)/libplasma Plasma::isPluginVersionCompatible: unversioned plugin detected, may result in instability
plasma-desktop(3963)/libplasma Plasma::isPluginVersionCompatible: unversioned plugin detected, may result in instability
plasma-desktop(3963)/libplasma Plasma::isPluginVersionCompatible: unversioned plugin detected, may result in instability
plasma-desktop(3963)/libplasma Plasma::isPluginVersionCompatible: unversioned plugin detected, may result in instability
plasma-desktop(3963)/libplasma Plasma::isPluginVersionCompatible: unversioned plugin detected, may result in instability
plasma-desktop(3963)/libplasma Plasma::isPluginVersionCompatible: unversioned plugin detected, may result in instability
plasma-desktop(3963)/libplasma Plasma::isPluginVersionCompatible: unversioned plugin detected, may result in instability
fenix@xcalibur:~$ plasma-desktop(3963)/plasma StatusNotifierItemSource::refreshCallback: DBusMenu disabled for this application
Connecting to deprecated signal QDBusConnectionInterface::serviceOwnerChanged(QString,QString,QString)
Object::connect: No such slot MediaPlayer::volumeChanged(qreal)
Object::connect: No such slot MediaPlayer::stateChanged(Phonon::State,Phonon::State)
Object::connect: No such slot MediaPlayer::seekableChanged(bool)
Object::connect: No such slot MediaPlayer::tick(qint64)
Object::connect: No such slot MediaPlayer::totalTimeChanged(qint64)
QCoreApplication::postEvent: Unexpected null receiver
QCoreApplication::postEvent: Unexpected null receiver
QCoreApplication::postEvent: Unexpected null receiver
QCoreApplication::postEvent: Unexpected null receiver
QCoreApplication::postEvent: Unexpected null receiver
Object::connect: No such slot DictApplet::updateColors()
loading state
static bool QDeclarativeMetaType::isModule(const QByteArray&, int, int) Qt 4.7 import detected; please note that Qt 4.7 is directly reusable as QtQuick 1.x with no code changes. Continuing, but startup time will be slower.
file:///usr/share/kde4/apps/plasma/plasmoids/calculator/contents/ui/calculator.qml:40: Unable to assign [undefined] to QString operator
KCrash: Attempting to start /usr/bin/plasma-desktop from kdeinit
sock_file=/home/fenix/.kde/socket-MYHOST/kdeinit4__0
KCrash: Application 'plasma-desktop' crashing...
KCrash: Attempting to start /usr/lib/kde4/libexec/drkonqi from kdeinit
sock_file=/home/fenix/.kde/socket-MYHOST/kdeinit4__0

Well, I figured out that it had to be something related to sockets as the 4 last lines say so.

By moving all the files from ~/.kde/socket-MYHOST/ to whatever folder I created just to rollback changes if nothing happened and running back plasma-desktop all came back to normality.

Well, that's all. I don't know if this solution will last long, Ill keep you inform
:)

GOOD BYE !

PS:

Qt: 4.8.4
KDE Development Platform: 4.10.5
Plasma Desktop Shell: 4.10.5

PLEASE PRESS THE LIKE BUTTON, THANK YOU A LOT!

[ S O L V E D ] Netflix Desktop has choppy video. Playing too fast in Linux

TESTED ON UBUNTU 's 15.10 (Wily) and 12.10 (Quantal Quetzal) and  13.04 (Raring Ringtail)

it works on every edition after 12.04

REVIEWED 02/23/2016

NETFLIX-DESKTOP

I am a Linux user, most of my time use Ubuntu. My distro was 12.04 for some months, but now I' ve installed Ubuntu to 13.04 version. In any of the above versions I was running with the same issue. Choppy videos when using NETFLIX.
After trying lots of different kind of things to solve this problem (with any luck on mi side) I figure that the problem consists that the videos where running too fast,  in fast forward, like 2 times faster making videos unwatchable and sound sharper. That's when I started to do some benchmark tests, and process speed comparisons.
Then, I came to the conclussion that the speed of the whole "netflix-desktop" "wine" "silverlight" and maybe other process launched from netflix-desktop were obeying the speed of the pulseaudio daemon, and this last was running too fast in my box, a 4 core cpu processor.

THE SOLUTION. (tested on 32 bits and 64 bits ubuntu distributions)

By slowing down the pulseaudio daemon with cpulimit, all run like a charm !

1- Install cpulimit if you don't have it. 

$ sudo apt-get install cpulimit

2- Launch cpulimit slowing down pulseaudio and run netflix after that.

$ cpulimit -e pulseaudio -c 1 -l 10 & netflix-desktop

(although I use pulseaudio, it could work for other audio daemons, you should try)

notes:
-e pulseaudio (finds the pid by the name)
-c 1 (uses only 1 core)

-l 10 (limit the core to 10% of its speed for the chosen application)

& netflix-desktop (runs netflix-desktop inmediatly after cpulimit succeeds launching)

ENJOY !!! (please "like" it if you find it useful)

Error reading /home/user/.nano_history: Permission denied Press Enter to continue starting nano.

Sometimes when trying to edit a text file using "nano" we face a not so important but yes annoying error message saying that  there is an error reading the file .nano_history from the current user home directory. Just by hitting the enter key it will proceed to the next step. But we want to fix this so the problem gets fixed so the next time we want to edit anything we  don't face this kind of issue any more.

Error reading /home/user/.nano_history: Permission denied
Press Enter to continue starting nano.

Don't panic, the error has a quick fix.

Run as root or sudo the following command:

sudo chmod 755 /home/<username>/.nano_history

Put the correct password at the prompt, and you are done!

Nano is a gui less text editor, it is perfect for text editting when there is no X session active, or maybe when you can't start your X right.

Most used commands with nano:

CTRL+O - Saves the file you are editting.
CTRL+K - Cuts the line where the cursor is.
CTRL+W - Searches a string inside the text file.
CTRL+T - Text correction
CTRL+X - Quits after saving if not saved there will be a question.

Error leyendo /home/user/.nano_history: Permiso denegado Pulsa intro para continuar iniciando nano

Algunas veces al tratar de editar o crear un archivo de texto utilizando editores de texto como  "nano"  nos encontramos con un mensaje de error que si bien no es importante, es molesto. Basta con presionar la tecla Enter para que el mensaje desaparezca y entremos en el programa para editar dicho archivo.

Este mensaje de error esta causado por no tener permisos para escribir en el archivo /home/usuario/.nano_history, si se fijan bien, el nombre de archivo comienza con un "." (punto), lo que en Linux significa que es un archivo oculto.

Para solucionarlo es necesario devolverle los permisos a dicho archivo (ya que fueron cambiados accidentalmente por lo general).

Basta con ejecutar el comando chmod 755 como root, o con sudo para distribuciones basadas en debian.

:~$ nano ./archivo.txt

Error leyendo /home/usuario/.nano_history: Permiso denegado

Pulsa intro para continuar iniciando nano

:~$ sudo chmod 775 ./.nano_history 

Password: (pon el password correcto)

y listo !

Ya no molestara mas este mensaje la próxima vez que deseemos crear o editar archivos de texto con nano.

Nano es un editor de texto muy potente para la terminal de linux. Carece de interfaz gráfica lo que lo hace una excelente opción para editar archivos de configuración cuando las cosas van mal y no pueden acceder al escritorio o manejador de ventanas.