MediaWiki is a very popular free and open-source wiki software that powers some of the most visited wikis on the Internet including the Wikipedia. You can also host it in your own environment for your own wiki requirements or for your organization.

At my work, we use MediaWiki for our developer's wiki site. When I started working for a new product team sometimes back, I came to know about this wiki format for the first time and I didn't like it very much.

After my previous post about why I chose Debian Testing as my current distribution, I wanted to share how I installed and configured Debian Testing. So that somebody out there looking for a guide to install their own Debian rolling system, will have at least a starting point.

Before I proceed with the post, please know that although I am a long time Linux user, with Debian, I just started my journey a couple of months back. And by no mean I am a seasoned Debian user. So whatever steps I am going to list in this post are the ones that I thought would be best suited for my requirement when I installed it on my system.

A few weeks back, I switched my home laptop to Debian and I wanted to write about my reasons behind choosing Debian and my experience with it for the first few days. But before I dive into that, here's a little background about myself. I have been using Ubuntu and later Xubuntu at home and later at office on my Desktop and on my Laptop for more than 7 years now and on the server front, I have worked on both Redhat/Centos and Ubuntu based systems. So I am not new to Linux at all.

If you are on Ubuntu 16.04 using radeon open source driver for your graphics card and having issues with playing mp4 or mkv files with VLC media player then read on. If you are not sure what graphics driver is in use in your system, paste the below line in Terminal.

lspci -v -s lspci | awk '/VGA/{print $1}'

And check for the below line in the output:

Kernel driver in use: radeon<br />

The issue occurs as soon as you open a media file of type mkv or mp4 with VLC media player. Immediately after opening, it crashes silently. But if you check the /var/log/syslog, you should be able to see segmentation fault messages.

Higher order functions are those functions that can return functions as their results. The returned function can then be invoked in the same way as you would invoke a normal function. In programming languages like Python, where functional programming is treated as a first class citizen, you can easily define higher order function like this.

def adder(a):
 def add(b):
  return a + b
 return add
add_with_5 = adder(5)
final_value = add_with_5(1)

Java on the other hand introduced functional programming in version 1.8. The support is still very primitive and it does not allow one to create higher order functions that return functions.