30.1.1.2 Supported Version Control Systems

VC currently works with many different version control systems, which it refers to as back ends:

• Git is a decentralized version control system originally invented by Linus Torvalds to support development of Linux (his kernel). VC supports many common Git operations, but others, such as repository syncing, must be done from the command line.
• CVS is the free version control system that was, until circa 2008, used by the majority of free software projects. Since then, it has been superseded by newer systems. CVS allows concurrent multi-user development either locally or over the network. Unlike newer systems, it lacks support for atomic commits and file moving/renaming. VC supports all basic editing operations under CVS.
• Subversion (svn) is a free version control system designed to be similar to CVS but without its problems (e.g., it supports atomic commits of filesets, and versioning of directories, symbolic links, meta-data, renames, copies, and deletes).
• SCCS was the first version control system ever built, and was long ago superseded by more advanced ones. VC compensates for certain features missing in SCCS (e.g., tag names for releases) by implementing them itself. Other VC features, such as multiple branches, are simply unavailable. Since SCCS is non-free, we recommend avoiding it.
• CSSC is a free replacement for SCCS. You should use CSSC only if, for some reason, you cannot use a more recent and better-designed version control system.
• RCS is the free version control system around which VC was initially built. It is relatively primitive: it cannot be used over the network, and works at the level of individual files. Almost everything you can do with RCS can be done through VC.
• Mercurial (hg) is a decentralized version control system broadly resembling Git. VC supports most Mercurial commands, with the exception of repository sync operations.
• Bazaar (bzr) is a decentralized version control system that supports both repository-based and decentralized versioning. VC supports most basic editing operations under Bazaar.
• SRC (src) is RCS, reloaded—a specialized version-control system designed for single-file projects worked on by only one person. It allows multiple files with independent version-control histories to exist in one directory, and is thus particularly well suited for maintaining small documents, scripts, and dotfiles. While it uses RCS for revision storage, it presents a modern user interface featuring lockless operation and integer sequential version numbers. VC supports almost all SRC operations.