2.2.1 Where files are stored within the repository

The overall structure of the repository is a directory tree corresponding to the directories in the working directory. For example, supposing the repository is in

/usr/local/cvsroot

here is a possible directory tree (showing only the directories):

/usr
 |
 +--local
 |   |
 |   +--cvsroot
 |   |    |
 |   |    +--CVSROOT
          |      (administrative files)
          |
          +--gnu
          |   |
          |   +--diff
          |   |   (source code to GNU diff)
          |   |
          |   +--rcs
          |   |   (source code to RCS)
          |   |
          |   +--cvs
          |       (source code to CVS)
          |
          +--yoyodyne
              |
              +--tc
              |    |
              |    +--man
              |    |
              |    +--testing
              |
              +--(other Yoyodyne software)

With the directories are history files for each file under version control. The name of the history file is the name of the corresponding file with `,v' appended to the end. Here is what the repository for the `yoyodyne/tc' directory might look like:

  $CVSROOT
    |
    +--yoyodyne
    |   |
    |   +--tc
    |   |   |
            +--Makefile,v
            +--backend.c,v
            +--driver.c,v
            +--frontend.c,v
            +--parser.c,v
            +--man
            |    |
            |    +--tc.1,v
            |
            +--testing
                 |
                 +--testpgm.t,v
                 +--test2.t,v

The history files contain, among other things, enough information to recreate any revision of the file, a log of all commit messages and the user-name of the person who committed the revision. The history files are known as RCS files, because the first program to store files in that format was a version control system known as RCS. For a full description of the file format, see the man page rcsfile(5), distributed with RCS, or the file `doc/RCSFILES' in the CVS source distribution. This file format has become very common--many systems other than CVS or RCS can at least import history files in this format.

The RCS files used in CVS differ in a few ways from the standard format. The biggest difference is magic branches; for more information see 5.5 Magic branch numbers. Also in CVS the valid tag names are a subset of what RCS accepts; for CVS's rules see 4.4 Tags--Symbolic revisions.