{"id":266,"date":"2018-07-13T08:51:12","date_gmt":"2018-07-13T08:51:12","guid":{"rendered":"http:\/\/itp7.epgpbooks.inflibnet.ac.in\/?post_type=chapter&p=266"},"modified":"2019-05-16T08:33:14","modified_gmt":"2019-05-16T08:33:14","slug":"version-control-system-git","status":"publish","type":"chapter","link":"https:\/\/ebooks.inflibnet.ac.in\/itp7\/chapter\/version-control-system-git\/","title":{"rendered":"Version Control System – GIT"},"content":{"raw":"
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Introduction<\/strong><\/p>\r\n \r\n

Programmers develop software on daily basis. Every day, they add more code to the existing program. So, the software keeps on evolving. To manage the changes made in the software on periodic basis, version control systems were developed. Imagine there is a team of developers working on the same project. When each programmer starts submitting their code, it will become difficult to track who submitted the code and when. In case, if we want to rollback to the earlier version, it will be difficult in simple file based system. The version control system manages the\u00a0changes made to system and if need arises, restores to some previous recall point. Although there are many version control system like CVS, Subversion, Perforce, Bazaar, and so on, GIT is an open source distributed version control system, we will study the GIT software in the module.<\/span><\/p>\r\n\r\n<\/div>\r\nVersion Control System<\/strong>\r\n\r\n \r\n

Version control system records changes to a file or set of files over time so that we can recall specific versions later on when required. A version control system keeps track of all changes made to a project. It allows many users to work in large teams on very complex projects while minimizing the conflicts between changes. Version control systems are necessary while developing software in teams. Each team member can have their own working copy of the project code without interfering with other developer\u2019s copies or the main trunk.<\/p>\r\n \r\n

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Figure 1: Version control system \u2013 Local, Centralized & Distributed(Image source: https:\/\/git-scm.com\/book\/en\/v2)<\/strong><\/p>\r\n \r\n

Few widely used version control systems include CVS (Concurrent Versions System), SVN (Apache Subversion), Git, etc. CVS is mostly a legacy system; SVN is a centralized system while Git is a decentralized system. Git is a free and open source distributed version control system designed to handle everything from small to very large projects with speed and efficiency. There can be multiple servers that can act as repositories, but each copy on each developer\u2019s own system is also a complete revision copy. Each team member can have their own working copy of the project code without interfering with other developer\u2019s copies or the main trunk.<\/p>\r\n \r\n\r\nOverview of GIT<\/strong>\r\n\r\n \r\n

Development of Git was initiated by Linus Torvalds in 2005. Git is written in C, Shell, Perl, Tcl and Python, Git supports OS like Linux, Windows, MacOS. Git is released under GNU GPLv2 and GNU LGPL License. GitHub is a web-based Git or version control repository and Internet hosting service. It offers all of the distributed version control and source code management (SCM) functionality of Git as well as adding its own features. It provides access control and several collaboration features such as bug tracking, feature requests, task management, and wikis for every project.<\/p>\r\n \r\n\r\nInstallation of GIT<\/strong>\r\n\r\n \r\n

GIT software is available for various platforms like Linux, MacOS, Windows and Solaris. Let us explore how to install GIT in our system.<\/p>\r\n \r\n\r\n\"\"\r\n

Figure 1: git software installation<\/strong><\/p>\r\n \r\n

For Windows, GIT can be downloaded from the website http:\/\/git-scm.com\/downloads, <\/a>The software is an installer file which can be installed in windows. Git has its own bash prompt and a command prompt. To install GIT in Linux, we must type the following commands at command prompt for Ubuntu based distribution and Red Hat based distributions respectively:<\/p>\r\n

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We must enter our name and email address (highlighted in red color) while configuring git. The above command will create a single repository on our local system.<\/p>\r\n \r\n\r\nGitHub.com<\/strong>\r\n\r\n \r\n

GitHub is a web-based Git or version control repository and Internet hosting service. It offers all of the distributed version control and source code management (SCM) functionality of git. It provides access control and several collaboration features such as bug tracking, feature requests, task management, and wikis for every project. GitHub.com allows us to share our open source code with others by creating a repository over internet. It is a hosting service, where it is free for open source software, however, those who want to create private repositories that is not visisble to others need to pay to maintain their private repository.<\/p>\r\n \r\n\r\nGithub allows to:\r\n