Use of CVS

History

Short Description

CVS (Concurrent Versions System) is installed there, with all its sources.

CVS keeps all versions and all branches of a particular source file "f.c" in a single file "f.c,v". This file has a structure which uses the differences from version to version, so that it takes up much less space than the corresponding set of versions. Access to versions is through a command "check out" and a new version is incorporated into this file through a command "check in".

The set of all ",v" files used for an application is called its "repository". The repository is structured as a hierarchy of directories, just like the sources for the application would be.

You never touch the repository except through commands given to CVS.

Normally you will start work by checking out of the repository a complete set of source files into your private work space. CVS will extract the sources and create the necessary directory structure in your space.

Development can then go on independently of any other person working on the same version: each developer has his own private copies.

When you have work ready, you will check in your files: CVS will incorporate the changes of all modified files into the repository as a new version.

More important: when a different developer has checked in some work (e.g. a bug fix), you can incorporate that into your current work *without* having to check in, by the "update" operation. Developers synchronise once in a while through updates.

There are also various means of identifying important versions.

WWW installation

The directory CVSRepository is where CVS stores the sources in the RCS format, i.e. one file for all versions and branches of each source file.

Please do not touch CVSROOT nor CVSRepository, they are to be maintained by use of CVS commands only.

CVS manual

(Note: Terry Hung introduced it at SLAC, but I believe we got it from the "standard" sources: prep.ai.mit.edu.)

RC