Version Control and Source Code Control Systems CS140 Dick Steflik

Version Control Systems Used on multi programmer projects to insure that developers don't accidentally destroy each other's changes Like a library: each user has to check files in and out, systems prevents one person from saving their changes to a file on top of another person's changes System enforces safe controls Changes are saved as a sequence of add, deletes and modifications to a base file, not as complete files (GIT works differently)

CVS Concurrent Versioning System Oldest of the version control systems Open Source Client-server architecture Originally developed for UNIX Ported to Windows NT Each time a file is checked in, user is required to enter a description of what was done Commandline and GUI based client programs are available.

Visual SourceSafe Originally developed by One Tree Software Original name was Delta Acquired by Microsoft and rebranded as Visual SourceSafe (1994)‏ Integrates with most Microsoft software development products Not Client Server based

Subversion Open Source version control system Circa 2000, goal is to be the preferred successor to CVS Widely used in the Open Source community for version control on projects like Apache, KDE, Gnome, gcc, python, ruby, Mono... Client-server architecture Commandline and GUI clients available for most OS environments. Saves changes in terms of things added and things deleted When retrieving a file from the system the system must reconstruct the file from previously stored adds and deletes When saving a file the system must analyze it to reduce it into a set of adds and deletes

GIT Developed by Linus Torvalds for managing the development of the Linux Kernel Based on BitKeeper and Monotone Currently has about 30% of the Software Configuration Market Each GIT Working directory is a full fledged repository, complete with history and versioning capabilities