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REGULAR EXPRESSIONS SPECIAL CHARACTERS EXPLAINED

Regular expressions” (often shortened to “regex”) is a language used to represent patterns for matching text. Regular expressions are the primary text-matching schema in all text-processing tools, including grep,egrep,awk ,sed.

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How To Install Tomcat 7 Server on CentOS/RHEL 5/6

Apache Tomcat is an opensource webserver product of Apache Foundation like Apache HTTP server. It is used to deploying Java Servlet and JSP applications. To deploy any application in Tomcat we can simply create a war fileand deploy them. For more details about you can visit apache official site.

 

Continue to following article to Install Apache Tomcat 7 on CentOS/RHEL Servers.  

 

Cantata 1.3.0 Music Player Released with 87 Fixes [Ubuntu Installation]

Cantata, a Qt-based music player for MPD (Music Player Daemon), has reached version 1.3.0 just yesterday, and a fix for compiling it in KDE, 1.3.0.1, was put out a few moments ago. This release comes with 87 fixes and improvements. Some major changes and new features include:

  • add option to control start-up state: visible, hidden or remembered from previous run
  • undo/redo support for play queue
  • many interface fixes and improvements
  • add remove duplicates functionality to playlists and play queue
  • read lyrics from the LYRICS tag in FLAC, Vorbis, Opus and Speex files

cantata_kdeapps01
Image source: Image credit

Overall, Cantata suffered major overhauls on all levels. The interface has suffered lots of fixes and improvements; communication with MPD was improved too; playlist and play queue handling also suffered fixes.

cantata_kdeapps02
Image source: Image credit

Installing Cantata 1.3.0 in Ubuntu 13.10

Installing from the PPA
Open the terminal and type the following commands to install Cantata from the PPA:

sudo add-apt-repository ppa:ubuntuhandbook1/cantata
sudo apt-get update
sudo apt-get install cantata

Installing from Source
Make seems to give the following error on Ubuntu 13.10 with Cantata 1.3.0 (this was fixed in Cantata 1.3.0.1):

lconvert: could not exec '/usr/lib/i386-linux-gnu/qt4/bin/lconvert': No such file or directory
make[2]: *** [translations] Error 1
make[1]: *** [po/CMakeFiles/translations.dir/all] Error 2
make: *** [all] Error 2

However, the binary is successfully built, available in the build directory and you can run Cantata as ./cantata.

Cantata 1.3.0.1 was released few moments ago with a fix for compiling it. Follow the next steps:

Download the source tarball from here and uncompress it:

tar -xjf cantata-1.3.0.1.tar.bz2

Next, install the dependencies:

sudo apt-get build-dep cantata

You will need the source repositories enabled for this to work.

Finally, change the working directory to cantata-1.3.0.1 and type the commands:

mkdir build && cd build
cmake ..
make
sudo make install

To install as normal user in a different prefix, use this:

mkdir build && cd build
cmake .. -DCMAKE_INSTALL_PREFIX=$HOME/usr
make
make install

Cantata offers a wealth of options, as well as Internet services like Jamendo and support for podcasts:

cantata03

 

Linux: Log Suspicious Martian Packets / Un-routable Source Addresses

A Martian packet is nothing but an IP packet which specifies a source or destination address that is reserved for special-use by Internet Assigned Numbers Authority (IANA). You can log packets with un-routable source addresses on Linux operating system. This tutorial explains how to log spoofed packets on Debian / Ubuntu / CentOS / RHEL / Linux based server.

Linux: Log Suspicious Martian Packets / Un-routable Source Addresses

 

Need a Good Bitcoin Client?

Bitcoin is a decentralized peer-to-peer payment system and digital currency that is powered by its users with no central authority, central server or middlemen. Instead, managing transactions and issuing money are carried out collectively by the network. Bitcoin is controlled by all Bitcoin users around the world.

To provide an insight into the quality of software that is available, we have compiled a list of 5 highly promising Bitcoin clients. Hopefully, there will be something of interest here for anyone who wants ease of use, security and advanced features.

[url=http://www.linuxlinks.com/article/20140216030924430/BitcoinClients.html]Read more[/url]

 

Cutting-Edge New Virtualization Technology: Docker Takes On Enterprise

Docker’s new container technology is offering a smart, more sophisticated solution for server virtualization today. The latest version of Docker, version 0.8, was announced couple of days ago.

Docker virtualization

Docker 0.8 is to focus more on quality rather than on features, with the objective of targeting the requirements of enterprises.

According to the software’s present developmental team; many companies that use the software have been using it for highly critical functions. As a result, the aim of the most recent release has been to provide such businesses top quality tools for improving efficiency and performance.

What Is Docker?

Docker is an open source virtualization technology for Linux that is essentially a modern extension of Linux Containers (LXC). The software is still quite a young initiative, having been launched for the first time in March 2013. Founder Solomon Hykes created Docker as an internal project for dotCloud, a PaaS enterprise.

The response to the application was highly impressive and the company soon reinvented itself as Docker Inc, going on to obtain $15 million in investments from Greylock Partners. Docker Inc. continued to run their original PaaS solutions, but the focus moved to the Docker platform. Since its initiation, over 400,000 users have downloaded the virtualization software.

Google (along with couple of most popular cloud computing providers out there) is offering the software as part of its Google Compute Engine though still nothing from major Australian companies (yes, I’m looking at you Macquarie).

Red Hat also included it in OpenShift PaaS as well as in the beta version of the upcoming release Red Hat Enterprise Linux. The benefits of containers are receiving greater attention from customers, who find that they can reduce overheads with lightweight apps and scale across cloud and physical architectures.

Containers Over Full Virtual Machines

For those unfamiliar with Linux containers, they are called the Linux kernel containment at a basic level. These containers can hold applications and processes like a virtual machine, rather than virtualizing an entire operating system. In such a scenario the application developer does not have to worry about writing to the operating system. This allows greater security, efficiency and portability when it comes to performance.

Virtualization through containers has been available as part of the Linux source code for many years. Solaris Zones was pioneering software created by Sun Microsystems over 10 years ago.

Docker takes the concept of containers a little further and modernizes it. It does not come with a full OS, unlike full virtual machines, but it shares the host OS, which is Linux. The software offers a simpler deployment process for the user and tailors virtualization technology for the requirements of PaaS (platform-as-a-service) solutions and cloud computing.

Docker images

This makes containers more efficient and less resource hungry than virtual machines. The condition is that the user must limit the OS host to a single platform. Containers can launch within seconds while full virtual machines can take several minutes to do so. Virtual machines must also be run through a hypervisor, which containers do not.

This further enhances container performance as compared to virtual machines. According to the company, containers can offer application processing speeds that are double than virtual machines. In addition, a single server can have a greater number of containers packed into it. This is possible because the OS does not have to be virtualized for each and every application.

The New Improvements and Features Present In Docker 0.8

Docker 0.8 has seen several improvements and debugging since its last release. Quality improvements have been the primary goal of the developmental team. The team – comprising over 120 volunteers for the release – focused on bug fixing, improving stability, and streamlining the code, performance boosting and updating documentation. The goals in future releases will be to keep the improvements on and increase quality.

There are some specific improvements that users of earlier releases will find in version 0.8. The Docker daemon is quicker. Containers and images can be moved faster. It is quicker building source images with docker build. Memory footprints are smaller; the build is more stable with fixed race conditions. Packaging is more portable for tar implementation. The code has been made easier to change because of compacted sub-packaging.

The Docker Build command has also been improved in many ways. A new caching layer, greatly in demand among customers, speeds up the software. It achieves this by eschewing the need to upload content from the same disk again and again.

There are also a few new features to expect from 0.8. The software is being shipped with a BTRFS (B-Tree File System) storage driver that is at an experimental stage. The BTRFS file system is a recent alternative to ZFS among the Linux community. This gives users a chance to try out the new, experimental file system for themselves.

A new ONBUILD trigger feature also allows an image to be used later to create other images, by adding a trigger instruction to the image.

Version 0.8 is supported by Mac OSX, which will be good news for many Mac users. Docker can be run completely offline and directly on their Mac machines to build Linux applications. Installing the software to an Apple Macintosh OS X workstation is made easy with the help of a lightweight virtual machine named Boot2Docker.

Docker may have gained the place it has today partly because of its simplicity. Containers are otherwise a complex technology, and users are traditionally required to apply complex configurations and command lines. Docker makes it easier for administrators, with its API, to easily have Docker images inserted in a larger workflow.

It is currently being developed as a plug-in that will allow use with platforms beyond Linux, such as Microsoft Windows, via a hypervisor. The future plans for the developmental team is to update the software once a month. Version 0.9 is expected to see a release early in March, 2014. The new release may have some new features if they are merged before the next release, otherwise they will be carried over to the next release.

Docker is expected to follow Linux in numbering versions. Major changes will be represented by changing the first digit. Second digit changes signify regular updates while emergency fixes will be represented by a final digit.

Customers looking forward to the production ready Docker version 1 will have to wait until April. They can also expect support for the software as well as a potential enterprise release. There are also attempts by the team to develop services for signing images, indexing them and creating private image registries.

Give it a try!

 

Basic Use of 'ls' Command With Examples for Beginners

One of the most used commands by Linux users and the one that a Linux beginner must learn is- 'ls' Command. It is usually used to view the contents of current directory. So, when you run this command, the files and sub-directories included under the current directory will be listed before you. Very useful command and everyone who uses Linux should know this command.

This article will guide you to know more about 'ls' command with it's basic usages. Here we start !

Read More at YourOwnLinux.

 

Understanding INODES in Linux/Unix Filesystems

The inode ( also known as Index Node) is a very basic concept related to Linux and UNIX filesystem. Each and every object/element in the filesystem is associated with an inode.

        You must be aware of the fact that, most of the countries have given a unique identity to their citizens in the form of a unique identification number ('Aadhar Card' in India and 'SSN' in the USA) to identify an individual easily and uniquely. This also leads to make all the paper work corresponding to any citizen easier to be handled.
    Just like these identification numbers for people, there is a unique identity of every member of a Linux filesystem which is known as Inode number and it uniquely exists for each and every individual file on Linux or Unix filesystems.

Read more at YourOwnLinux.
 

QuickLicenseRT Linux Can Protect and License Desktop Software

Excel Software announced QuickLicenseRT Linux for desktop software. QuickLicenseRT Linux implements the full QuickLicense runtime system for protection, activation and license management. A company can protect software from piracy and increase revenue by supporting a wide range of license types, activation processes and advanced licensing features.

During development, QuickLicenseRT Linux is used in conjunction with QuickLicense running on a Mac OS X or Windows computer. The developer configures all aspects of the software license with QuickLicense and builds a tiny encrypted Ticket file. That Ticket file is bound to a Linux desktop application with a few lines of programming code that sends commands to the QuickLicenseRT executable.

Linux programmers enjoy a quick, integrated solution for almost any software protection, activation or licensing requirement. The runtime allows one software build to support Trial, Product, Subscription, Floating, Try/Buy or Educational licenses. The activation process for protected software allows manual activation without Internet access, semi-automated activation through a web browser or fully automated activation through an online activation server.

While one license command is sufficient for many applications, the runtime library supports dozens of command strings to access all licensing features available in the QuickLicense system. Runtime commands include license release, restore, reset, suspend, remote enabling of features, field read and write, plus data send and receive through the activation server.

Without writing any software, a developer can configure language specific interfaces for any human language. A configurable License Options panel allows protected software to be securely moved between computers, features to be remotely enabled or time and execution expired licenses to be extended.

QuickLicenseRT Linux is part of the suite of Excel Software protection and licensing solutions for Mac OS X, Windows, Linux, Android, Mobile or Web software. Computer unique Activation or Subscription Codes for protected Linux applications can be generated with QuickLicense or LicenseSupport. Custom online activation can be automated with Serial Numbers using the Safe Activation service or the self-hosted WebActivation or Desktop License Server products running on a vendor website.

QuickLicenseRT Linux supports all major Linux distributions including Ubuntu, Debian, OpenSUSE, Fedora and CentOS on an x86 computer architecture. A Single User License at $395 includes royalty-free runtime distribution rights for any number of protected products or licenses. The package includes a User Guide and the SendMessage test application to try all license types and commands without any programming. Contact Excel Software for a Demo edition or free access to an extensive video library on topics related to software protection, license management and automated order processing for any type of digitial product.

Excel Software
Ph: (702) 445-7645
Fax: (702) 445-7814
Web: www.excelsoftware.com
Email: This e-mail address is being protected from spambots. You need JavaScript enabled to view it

 

 

 

 

 

 

 

A Non Changing Experience In A Changing Environment

We all love the variation that comes with Linux. But if you could why not make it optional for those who want the same experience when changing distribution. I wonder if a version of the operating system could be run from the browser and control the native one. A simplified version would mean that a novice could operate a lot of different desktop environments. Like GNOME, Unity, Cinnamon, MATE, KDE, Xfce, LXDE and Enlightenment. If a larger group of distributions would work together on something like this I think it would make it easier for those distributions to exist in the workplace.

With this you could take advantage of the creativity in web development and a non changing experience for those who want that.

 

Linux Networking Simplified

Making optimal use of the network with Linux for varied purposes such as remote login, network statistics, alive test, and many more, is very essential in day-to-day usage. Linux Networking is incredibly simplified with the following elaborated Linux Network Commands.

For more details, see at  Techdarting.com - Linux Network Commands Simplified

 
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