PVCS Version Manager

The basic features of this version control system are:
Member storage
PVCS simplifies access to project components: code, data files, documentation, object modules, and other binary files. Developers and administrators need not remember where each module is stored. PVCS locates files or projects even across system boundaries. High-level support for module sharing makes PVCS essential on heterogeneous networks.
Access control
PVCS offers precise control of file locking on the LAN to prevent conflicting updates of shared files. Users can be assigned to groups that have specific file access capabilities.
Parallel development
PVCS lets developers create multiple logical views of the same physical modules, so they can create, maintain, and test special versions of an application. Unlimited branching offers flexible, yet safe, parallel development and makes alternative versions easy to maintain. A merge facility resolves conflicts as you merge multiple development efforts to produce the application.

Furthermore, PVCS Version Manager comes with a graphical user interface on all platforms, however all commands can also be called from the command line.