solving a start job is running for create volatile files and directories : manjaro linux

I have used Manjaro Linux which is Arch Linux based system for several month. Manjaro using roling system update, so we don't need to install new distribution to use latest version. We only need to upgrade through update manager.

After several times I used roling update then I restart my system boot time take long time, and plymouth like freeze. When I press escape to view error message on boot time. I got this message.

a start job is running for create volatile files and directories

 I search internet but I got nothing to solve my problems, then I try to view my manjaro setting then I take look on kernel section, I know that my kernel is need to be upgrade. Manjaro system will notif recommended kernel version for installed system if newer kernel exist.

 

Install Recommended kernel from kernel section, after installation finish I restart my system and  it's like a magic all error message and boot time back to normal :).

#good luck have fun

Manjaro XFCE Post Installation Tips and Tricks

To read original article go to here.

It's nearly a year since my last post, a lot of things had happened in between, Placement preparation, couple of interviews, six month internship in Blackberry Platform at Payoda Technologies  and finally completion of my studies. During this period a lot of distros had been released but I stayed with the stable Opensuse, but then I felt KDE version of opensuse is little bit heavy, which can be felt during both start-up and during normal day to day usage(say Eclipse+amarok+chrome) even with 4GB RAM and i3 Processor.

I started my quest for "The best GNU/Linux OS" with distrowatch.com. Since I wanted a lighter distro but not certainly like Puppy/Tiny and no Ubuntu/Debian forks then by default I left with Arch. But the fear of  two earlier failed attempts to install Arch forced me to try arch fork than arch. Seeing Manjaro  Linux description "Manjaro Linux is a desktop-oriented, user-friendly distribution based on Arch Linux" , I thought I would give it a try. Downloaded and Installed manjaro-xfce-0.8.5.1-x86_64 from Manjaro site.

The first thing I noticed with Manjaro is, it's fast start-up and shutdown time, it is comparatively faster than opensuse. Here are the some of tricks which I had done to achieve what's in their description user-friendly distribution. NOTE: No Graphics driver installation tips are given because author himself followed the steps listed in Beginner's guide and finally ended with blank screen even though he only have Intel's Integrated graphics card. 

Manjaro Linux: Arch For People Who Don’t Have Time

I am manjaro Linux user, and want to share how arch linux based system transform into friendly distro for end user.

This article originaly from make use of site.

There are plenty of things that make Arch Linux highly appealing to users: it’s always up-to-date, it’s a rolling release, and there’s tons of software available for it in its repositories. But what isn’t so appealing is the learning curve and pure difficulty of setting up an Arch system. If you want the best aspects of Arch, without the bad parts, you need Manjaro Linux.

About Manjaro Linux

Manjaro Linux is an Arch-based distribution, meaning that it runs on the same backbone and the same repositories as Arch itself. It also implements the rolling release upgrade model, meaning that you never have to perform a major upgrade from “release 1″ to “release 2″ – just update your packages and you’ll be up-to-date.

However, unlike Arch, it doesn’t require that users build up systems on their own. This isn’t to say that setting up the Arch way is a bad thing, or that it’s too difficult – there’s plenty of documentation for the job. But some people simply don’t have the time, regardless of their skill level.
There’s a lot of fuss among Arch users whether they should support Manjaro, and while some believe that it goes against everything Arch stands for, I think it’s a good option for those who want it.
Also unlike Arch, there are some defaults when it comes to the included software. For example, Manjaro defaults to the Xfce desktop environment (which is lightweight and awesome), although official Openbox,(a very minimal desktop environment), and KDE (a desktop environment with lots of eye candy) versions are available as well. Other desktop environments, such as Gnome, are available as “Community Editions”.

Don’t Fear the Beta!

Technically speaking, Manjaro is still a beta distribution – its version sits at 0.8.9 at time of writing. This shouldn’t push away any potential users. The main reason why Manjaro is still considered a beta distribution is because of the Manjaro additions to the otherwise stable Arch packages that are installed. Things like the Manjaro installer and the Pacman (package manager) graphical frontend are still beta, but everything else that is on the system are stable versions of the software that Arch offers in its repositories.

Scary Steam for Linux bug erases all the personal files on your PC

Original Article From pcworld

If you’re a Steam fan running Linux, the last thing you’ll want to do in the next few days is mess with your Steam files. Users on Valve’s GitHub Steam for Linux page are complaining about a nasty bug that has the potential to wipe out every single personal file on your PC. Even worse, users say the bug will even wipe out documents on USB connected drives. So much for local backups.
The impact on you at home: The obvious implication if you’re running Steam on Linux is to be wary of the program right now. As a precaution, don’t connect any local external hard drives while you’re running Steam. Users complaining of this bug appear to have moved their .steam or ~/.local/share/steam directories, or invoked Steam’s Bash script with the —reset option enabled.

UPDATE: Valve gave us the following statement: "So far we have had a handful of users report this issue, after they manually moved their Steam install. We have not been able to reproduce the reported issue, but we are adding some additional checks to ensure this is not possible while we continue to investigate. If anyone else has experienced this or has more information, they should email linux@valvesoftware.com."

Ouch

Steam’s bug appears to be caused by a line in the Steam.sh Bash script: rm -rf “$STEAMROOT/“*. That command is a basic Bash instruction that tells the computer to remove the STEAMROOT directory and all its sub-directories (folders).
That’s all well and good, but the issue is that if the STEAMROOT folder is not there then the computer interprets the command as rm -rf “/“*, as first reported by Bit-Tech. If you’re not familiar with Bash, that command tells the system to delete everything on your hard drive starting from the root directory.
The saving grace for Linux users is that you can only erase files you have write permissions over. That means the system itself can’t be erased, but pretty much all of a user’s files—including photos and personal documents—would be at risk.
Ironically, the instruction at issue is preceded by a comment from the developer: # Scary!.
Indeed.
Editor's note: This article originally published on 1/16/15, but was updated on 1/17/15 to include Valve's statement.

pkg_config libvala problem

Today I resolved error when compiling monodevelop from git source, that need libvala-0.12 or higher. But when I installed libvala-0.22 and try to ./configure there is error appear, it said that libvala-0.12 not found. :-(

No package 'libvala-0.12' found

Then I googling but nothing result to solve, but I figure it out pkg_config is program that extract information from *.pc about installed library. Then I find libvala-0.22.pc in my Ubuntu OS.

amru@blackstar:/usr/lib/x86_64-linux-gnu$ sudo find / -iname *.pc | grep libvala
/usr/lib/x86_64-linux-gnu/pkgconfig/libvala-0.22.pc

Got it, then I create soft link using "ln" command,

amru@blackstar:/usr/lib/x86_64-linux-gnu$ sudo ln -s /usr/lib/x86_64-linux-gnu/pkgconfig/libvala-0.22.pc /usr/lib/x86_64-linux-gnu/pkgconfig/libvala-0.12.pc

VIOLA, ./configure work prefect :D.

Koding.com the social collaborative plaform

Last time I tried openshift from RedHat, it's good platform. But there is some thing that I don't get is about root access to virtual machine, and live code editing :-), with koding platform I get 20GB for a free, root access to virtual machine, live code editing, social collaborative and the best part is I don't really need local setup for development because I can code on the fly for testing app :-).

The thing is we need to register to koding.com to get 20GB free storage and awesome platform.

With this I try to create web application, but still in progress hope I can finish this in 2014 :-) and make something useful for other people.

Some awesome feature:

1. Social Development, also you can create interactive class for tutoring

Cross Site Request Forgery protection (CSRF)

Original Image from here.

I just build some web application using Django, and I found some interesting thing when using Ajax through Django Framework.

I am not deep in knowledge and advance programmer nor developer, just like script kiddies and I always want to know about new thing. Formerly I am Python big fan, so I want to create something with Python. Not only for building system nor system programming but I want to make something different :-).

In Django if we want to request using Ajax, Django will response with access forbidden. Why? because Django care about security to prevent again Cross Site Request Forgery protection (CSRF). Which is the first defense against CSRF attacks is to ensure that GET requests (and other ‘safe’ methods, as defined by 9.1.1 Safe Methods, HTTP 1.1, RFC 2616) are side-effect free. Requests via ‘unsafe’ methods, such as POST, PUT and DELETE.

At first time I confuse how to use it :-D #newbie, but then I found good documentation from Django documentation, very clear and bulls eye.

Go to here for more information how to use CSRF on Django.

RedHat OPENSHIFT Cloud

Today I will write my experience using Openshift cloud framework from RedHat, It's not just cloud storage but it's complete application framework cloud base. #In my Opinion Openshift based on Redhat Openstack Cloud.

What really I get from Openshift ?

OpenShift is Red Hat's Platform-as-a-Service (PaaS) that allows developers to quickly develop, host, and scale applications in a cloud environment. With OpenShift you have choice of offerings, including online, on premise, and open source project options.

One thing why I like Openshift ? because is about easy development, I don't care about backend from Openshift but I just need care and focused on how my code will work and how it should be deployed. Just in case in Openshift you already have many server language based, you just need to select which one is appropriate to you :D + git integration. It's like one shot. #damn.

First thing that you need to do is sign up, is it easy ? of course, you just need to fill detailed form in sign up form. No need to be worried :D, after finish sign up you will get 3 different application + 1 GB free space. So you can create and develop your application until you really want to release your application.

After sign up success, you can start create new application depend on your based server side language, it's about 5 minute to setup :D. What do you want ? just do simply select and follow the instruction.

In this case I'd like to select and setup DJango framework #coz I like Python :D, you can select which database you will use I'd like to select Postgresql and it will automatically create your git repository in the Openshift, so don't worry you just need to fill ssh key for clone project purpose.

After finish setup application, next step I need to do is to clone my application from Openshift in to my local computer. Then you will get this layout tree after you do git clone.

But it will give different file list, depend on what server side framework do you select. I just need to open setup.py then change configuration field.

The final step I need is just need to push again setup file configuration via git in to Openshift, Openshift will take a rest of installing framework do you need. :D.

Then start create your code and make great and use full application for human being :D

Setup Eclipse C++ and OpenGL support on Ubuntu Linux

Currently I am using Ubuntu 12.04 and Eclipse Version 3.7.2. I am trying to write little note how to setup Ubuntu Linux and Eclipse C++ for developing openGL purpose.

We usually use Glut, FreeGlut and Mesa for developing openGL in Linux  system. We need to get update from Ubuntu repository before installing openGL development resource and then second step install the openGL library.

sudo apt-get update
sudo apt-get install libglu1-mesa-dev freeglut3-dev mesa-common-dev

After resource got installed, we need to setup Eclipse IDE, Eclipse can be done by install from Ubuntu repository with CDT Support.

sudo apt-get install eclipse eclipse-cdt eclipse-cdt-jni

After all tools installed, now it's time to start setup Eclipse IDE and then after Eclipse started, we need to create new C++ project using menu File->New->C++ Project or using key shortcut Shift+Alt+N.

Select Empty Project and Cross GCC then give project name to whatever, in this case I use "opengl_glut" as project name. Then select finish button to completed creating project.

Before start create code, we need to add some linker option, so when linker process the library can be found by linker program. To add glut library on the linker process can be complete by using rigth click on the opengl_glut project then select properties.

Choose C/C++ Build Section, select Setting then select Libraries on C++ Linker section. Add "glut" and "GLU" library on the project then select Ok Button to apply changes.

Now we can start openGL code, create main.cpp by right click on the opengl_glut project and select New->File then give File Name as entry point "main.cpp". Add this code to main.cpp to check if our Eclipse setting is correct:

#include <GL/glut.h>
#define window_width  640
#define window_height 480
// Main loop
void main_loop_function() {
    // Z angle
    static float angle;
    // Clear color (screen)
    // And depth (used internally to block obstructed objects)
    glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
    // Load identity matrix
    glLoadIdentity();
    // Multiply in translation matrix
    glTranslatef(0, 0, -10);
    // Multiply in rotation matrix
    glRotatef(angle, 0, 0, 1);
    // Render colored quad
    glBegin(GL_QUADS);
    glColor3ub(255, 000, 000);
    glVertex2f(-1, 1);
    glColor3ub(000, 255, 000);
    glVertex2f(1, 1);
    glColor3ub(000, 000, 255);
    glVertex2f(1, -1);
    glColor3ub(255, 255, 000);
    glVertex2f(-1, -1);
    glEnd();
    // Swap buffers (color buffers, makes previous render visible)
    glutSwapBuffers();
    // Increase angle to rotate
    angle += 0.25;
}
// Initialze OpenGL perspective matrix
void GL_Setup(int width, int height) {
    glViewport(0, 0, width, height);
    glMatrixMode(GL_PROJECTION);
    glEnable(GL_DEPTH_TEST);
    gluPerspective(45, (float) width / height, .1, 100);
    glMatrixMode(GL_MODELVIEW);
}
// Initialize GLUT and start main loop
int main(int argc, char** argv) {
    glutInit(&argc, argv);
    glutInitWindowSize(window_width, window_height);
    glutInitDisplayMode(GLUT_RGB | GLUT_DOUBLE);
    glutCreateWindow("GLUT Example!!!");
    glutIdleFunc(main_loop_function);
    GL_Setup(window_width, window_height);
    glutMainLoop();
}

Build the code by right click on the opengl_glut then select Build Project menu, this should compile without any error. Then select menu Run->Run or using shortcut Ctrl+F11. If no error, the sample should become to be like this...then we completed all setting setup step for openGL development environment using Eclipse in Ubuntu Linux system.

Compare image scan method

Original Image Link

In this section I will try to compare performance from some scanning method using OpenCV, the compare is about performance image scanning for manipulate per color data.

What will be compare on this section:

• Classic C style operator scanning method
• Iterator safe method scanning method
• On-the-fly address calculation with reference returning scanning method
• Use LUT() core function from OpenCV

Setup OpenCV With QT Creator

OpenCV (Open Source Computer Vision) is a library of programming functions for real time computer vision.

OpenCV is released under a BSD license, it is free for both academic and commercial use. It has C++, C, Python and soon Java interfaces running on Windows, Linux, Android and Mac. The library has >2500 optimized algorithms (see figure below). It is used around the world, has >2.5M downloads and >40K people in the user group. Uses range from interactive art, to mine inspection, stitching maps on the web on through advanced robotics.

How to install opencv? it's depend on our operating system, installation procedure can be found here http://opencv.willowgarage.com/wiki/InstallGuide.

I assume that OpenCV already installed on the computer, it's easy to integrate OpenCV lib and header to QTCreator

• Create Empty QTCreator Project

 Open QTCreator and creaate empty QT Project File -> New File or Project

then give the project name, in this case I use OpenCV as project name.

• Add Library OpenCV to .pro file project

 Open .pro file and add OpenCV library, in this case I use Linux as my operating system so in the .pro file will be like this