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Top Terminal Multiplexer Tools

The phrase 'terminal multiplexer' sounds a bit of a mouthful and a large dollop of jargon. Multiplexing is a method of combining multiple data streams into one stream over a shared medium. This gives us a hint of the function of a terminal multiplexer. It is computer software that can be used to multiplex several video consoles. In English? Well, it allows you to make use of multiple separate terminal sessions inside a single terminal. So one terminal session can act like many sessions.

<A HREF="http://www.linuxlinks.com/article/20141227174048933/TerminalMultiplexerTools.html">Full article</A>

 

12 of the Best Free Git Books

Git is the most widely used version control system, in part because of the popularity of GitHub, a web-based Git repository hosting service, which offers all of the distributed revision control and source code management) functionality of Git as well as adding its own features.

The books featured in this article are all available for free, and many of them are released under an open source license. Some of the text are designed for beginners, others help developers get to grip with the somewhat ugly internals of Git. So get reading, learning and sharing code.

<A HREF="http://www.linuxlinks.com/article/20141221023950260/GitBooks.html">Read more</A>

 

Soft Links (i.e.Symlinks or Symbolic Links) and Hard Links in Linux File Systems

Most of us know that, every single component of Linux file systems is associated with an Inode. Every single element in the Linux file systems is uniquely identified by an Inode number. In one of my previous articles, Understanding Inodes in Linux/Unix File Systems, I have explained 'What Inodes are', 'How they can be accessed' and 'How they are used'.

This article can be considered as a continuum of the above mentioned article and this article will elaborate on Links in Linux file systems, which are Soft Links (also known as Symlinks or Symbolic Links) and Hard Links.

Here we go!

What are Links..?

Links in Linux/Unix can are very much similar to Pointers in programming languages. The basic difference is that, Pointers in programming languages are used to point to the other variables, likewise Link is a pointer to a file or a directory. Creating a links is very much similar to creating a shortcut to a file in order to access it.

There are two kinds of these links based on their properties, which are:
1. Soft Links or Symbolic Links or Symlinks
2. Hard Links

Let's see what exactly they are.

Soft Links:
If you have been using Windows operating systems, understanding Soft Links would be an easier task for you. You can just compare Soft Links in Linux with the 'shortcuts' in Windows, they do not possess any information in them, but they point to the location of a file or a directory in the file system. Eventually, when original file is lost, Soft Links lose their importance.

Hard Links:
Again, when compared to Windows operating systems, Hard Links in Linux are very much similar to 'Copy' of a file in Windows. A bit of difference is that, whenever any changes are made to original file, those changes are reflected in the Hard Links, unlike in Windows. But, when the original file is lost, the contents in the Hard Links are still preserved. How? Lets see in the upcoming section.

 

Read more at YourOwnLinux

 

 

Running Nova-Docker on OpenStack RDO Juno (CentOS 7)

Recently Filip Krikav made a fork on github and create a Juno branch using
the latest commit + fixing the problem of loading an image from glance
https://github.com/fikovnik/nova-docker/tree/juno   Posting bellow is supposed to test Juno Branch
https://github.com/fikovnik/nova-docker.git.   Complete article may be viewed here

 

How To : Install NVIDIA 340.65 Graphics Drivers in Ubuntu/Linux Mint Systems

The latest version of Nvidia Graphics driver for Linux which is Nvidia 340.65 has been released and is available for download. It comes with plenty of fixes and changes. This article will guide you to install Nvidia 340.65 in Ubuntu and Linux Mint systems.

Fixes

  • Added support for X.Org xserver ABI 19 (xorg-server 1.17).
  • Improved compatibility with recent Linux kernels.
  • Fixed a bug that prevented internal 4K panels on some laptops from being driven at a sufficient bandwidth to support their native resolutions.
  • Fixed a regression that prevented the NVIDIA kernel module from loading in some virtualized environments such as Amazon Web Services.
  • Fixed a regression that caused displays to be detected incorrectly on some notebook systems.
  • Fixed a bug that could cause X to freeze when using Base Mosaic.
  • Fixed a regression that prevented the NVIDIA X driver from recognizing Base Mosaic layouts generated by the nvidia-settings control panel.

Read more at YourOwnLinux.

 

How To: Install Linux Kernel 3.18.1 in Ubuntu/Linux Mint Systems

The Linux Kernel 3.18.1 is now available for the users, announced Linus Torvalds. This Linux Kernel version comes with plenty of fixes and improvements. This article will guide you to install or upgrade to Linux Kernel 3.18.1 in your Ubuntu or Linux Mint system.

 

Read more at YourOwnLinux.

 

How to setup a mail server with Postfix and Dovecot on Ubuntu / Debian

Mail system for your own domain You have your own domain name and your very own vps/dedicated server and want to use the domain name for emails. So you need to setup a mail server using an smtp server and an imap/pop server. This tutorial shows you how to setup Postfix (smtp server) and Dovecot (imap/pop server). The task of the smtp server is to accept incoming mails and relay outgoing mails from authorised users on the system. Whereas Dovecot allows authorized users to access their Inbox and...
Read more... Comment (0)
 

Howto Decorate Bash Prompt

The Bash shell provide users with a very customisable prompt through the variable named PS1 for the primary prompt and PS2 for the secondary prompt. This Howto is the basics to get started.

Simplest method to test changes to the prompt is by entering the following at the prompt and the immediate changes will be shown at the user prompt in the next press of the "Enter" key.

export PS1='Hello world$ '

This will display the words "Hello world$" followed by a space before the cursor.

Backslash-escaped Special Character

Users find it useful with their server hostname, user name, date, time, directory and all sorts of stuff displayed with their prompt. The list can be found at Bash Prompt from TLDP, here are listed a few;

  1. \d - the date  in  "Weekday  Month  Date"  format (e.g., "Tue May 26")
  2. \e - indicate an ASCII escape character (033)
  3. \h - the hostname up to the first '.'
  4. \n - newline
  5. \t - the current time in 24-hour HH:MM:SS format
  6. \T - the current time in 12-hour HH:MM:SS format
  7. \u - the username of the current user
  8. \W - the basename of the current working directory

Example 1: Common user name, server host name and working directory display

export PS1='[\u@\h \W]\$'

Example 2: Display current time and prompt in 2nd line

export PS1='\d [\u@\h \W]\n\t \$'

Colours

Font colour is a assigned with the sequence \[\e[colourcode\] where the colour code in combination of font style and ansi colour code (see TLDP). All colour escape sequences must be followed by letter 'm'.

Ansi colour code

  1. Black      0;30m
  2. Dark Gray     1;30m
  3. Blue        0;34m    
  4. Light Blue    1;34m
  5. Green       0;32m    
  6. Light Green   1;32m
  7. Cyan        0;36m    
  8. Light Cyan    1;36m
  9. Red         0;31m    
  10. Light Red     1;31m
  11. Purple      0;35m    
  12. Light Purple  1;35m
  13. Brown       0;33m    
  14. Yellow        1;33m
  15. Light Gray  0;37m    
  16. White         1;37m

\[\e[m\] Closing colour code

Example 1: Display common prompt as green and following character typed is also green. Its shown 2 ways of writing same prompt

export PS1='[\[\e[0;32m\]\u@\h \W]\$ 'export PS1='[\[\033[0;32m\]\u@\h \W]\$ '

Example 2: Display common prompt as green and following character typed is default colour

export PS1='[\[\e[0;32m\]\u@\h \W[\e[m\]]\$ '

Example 3: Contrast colours to highlight

export PS1='\[\e[1;34m\]\u\[\e[1;33m\]@\[\e[1;32m\]\h\[\e[1;37m\](\[\e[1;31m\]\W\[\e[1;37m\]) \[\e[1;36m\]\$ \[\e[0m\]'

Saving changes

Changes can be saved to ~/.bashrc to make sure that it is applied each time a user access the terminal.

To make this global, add the PS1 line to the /etc/bashrc. This however is always overridden by the user's ~/.bashrc configuration.

Example of ~/.bashrc:

# .bashrc# Source global definitions
if [ -f /etc/bashrc ]; then
    . /etc/bashrc
fi
# User specific aliases and functions
 

What would become of this world if we could not share knowledge

We are living in an age where free flow of information has become vital to human progress. Information is free because is it believed that the more we share, the more we learn, the more we do. That is the open source philosophy. Make software free, not as in cost, but as in freedom to change and recreate. 

I personally do not want to live in a world that keeps valuable information that supports innovation behind bars. We learn from others. Ideas come in many forms. The more ideas implemented within a product, the more usefull and complex it becomes. Importantly, it never stops evolving. 

I am an avocate of sharing information, but under a specific category. The only information that I care to share and collect is technological information that either helps improve or develop new technological products or technological services. It is information that we all need and cannot live without. Decide for yourself. Invision a world without open source.

 

Why open source runs the world

 

Star Wars Luke Skywalker freecomputerdesktopwallpaper 1600

 

 

 

 

How To : Install Linux Kernel 3.17.6 in Ubuntu/Linux Mint Systems

The Linux Kernel 3.17.6 is now available for the users, announced Linus Torvalds. This Linux Kernel version comes with plenty of fixes and improvements. This article will guide you to install or upgrade to Linux Kernel 3.17.6 in your Ubuntu or Linux Mint system.

Read complete article Here.

 

A beginner's guide to bash

A Brief Introduction
Bash or Bourne again shell is a replacement to the original unix shell written by Stephen Bourne at Bell Labs.

It offers vast improvements over the original shell, which include
Integer arithmetic,
Indexed arrays,
Command line editing,
Unlimited command history.

Bash scripts are available by default on most Linux distributions.

http://techarena51.com/index.php/a-beginners-guide-to-bash-scripting/

 
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