Concurrent Versions System
The Concurrent Versions System (CVS) is an essential component of Source Configuration Management. It is a free revision control system through which a user can record the history of source files. Open-source developers widely use it to manage a source code repository. CVS stores only the differences between the versions instead of saving every version for every file. It allows merging the work done by several developers making it a good point from an open-source developers perspective. It manages various module versions so that if a future version encounters a defect, then a past version can be referenced.
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CVS allows isolating changes onto separate lines of development known as branches. The changes in a file are not reflected on the main trunk.
Need of CVS
A developer needs to maintain several documents associated with a project. The process of efficiently managing such resources can be challenging. In some situations, the advanced and improved version can have less accuracy than their previous versions. In that case, the developer needs to switch back to the previous modules. Hence, parallel management of both modules is essential. This can be accomplished by a special database that can store software-related data. This is where CVS comes into the picture.
CVS manages consistency among files using the following concepts:
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File locking ensures that one person modifies the file at a time. The same file modified by several users can be monitored using the watch command.
- It ensures appropriate policies to avoid conflicts in files modified by a developer.
Features of CVS
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Real-time Collaboration: Several developers working on different components from several geographical locations can simultaneously collaborate on a single project.
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Source File History: It allows a developer to roll back to the previous version if the new version displays less accuracy or more bugs.
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Owned Branches: Several developers work on the same project and different components. It allows developers to manage their branches that can be merged later to avoid conflicts with each other's works.
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Flexible Module Database: All the logs which contain the commits and the changes made by the developers are stored in the database.
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Repository Event Triggers: In case of any modification in the repository, an alert is sent to the developers containing the information regarding the new update.
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Checkout Usage Model: Checkout is creating a copy of the current repository and then committing changes in the repository and at last updating the repository so that it has the new version of the project.
Important CVS Commands
- cvs checkout: Check out the source for editing.
- cvs add: Add new files to the repository.
- cvs remove: Remove an entry from the repository.
- cvs status: Display status of the checked-out files.
- cvs log: Display revision history for the files.
- cvs differ: Compare working files to the versions in the repository.
- cvs update: Sync working files with the files in the repository.
- cvs commit: Check files into the repository.
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cvs tag: label the sources.
Advantages and Disadvantages of CVS
Advantages:
- It allows developers scattered at different locations to work on a single project simultaneously.
- It can run scripts that allow users to log CVS operations or enforce site-specific policies.
- It has good support from a huge CVS community.
- It provides a strong and fully featured command-line client.
- It provides excellent cross-platform support.
Disadvantages:
- No integrity checking for the source code repository.
- Checkout and commits are not atomic.
- Poor support for distributed source control.
- CVS manages revision on a file-to-file basis.
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More oriented towards text files can mess up the management of binary files.
FAQs
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What is the most used version control system?
Git is one of the most widely used version control systems. It can be used on various platforms with numerous repository systems.
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What is the purpose of version control software?
It facilitates sharing, coordination, and collaboration across the entire development team. It allows developers to work in a distributed and asynchronous environment, manage changed code versions, and resolve merge conflicts.
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What is a merge conflict?
A merge conflict occurs when Git cannot automatically resolve code differences between two commits.
Key Takeaways
In this article, we have extensively discussed Concurrent Version Systems. CVS is a free revision control system through which a user can record the history of source files. It allows merging the work done by several developers making it a good point from an open-source developers perspective.
We hope that this blog has helped you enhance your knowledge regarding concurrent version systems, and if you would like to learn more, you can follow our guided path. Do upvote our blog to help other ninjas grow.
Happy Coding!