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© FUOC • P07/M2101/02709 116 Free Software
8.5.1. CVS
CVS (Concurrent Version System) is an optimistic source management system
designed towards the end of the eighties and used by the vast majority of
free projects (Concurrent Version System [20], Open source code development
with CVS, 2 nd edition) [113], "The Internet standards process", 3 rd revision[95]).
It uses a central repository accessed through a client/server system. The site
administrator decides who has access to the repository, or to which parts of the
repository, although normally, once a developer has been admitted within the
circle of trust, he will have acess to all files. Anonymous access, in read-only
mode, may also be allowed for anyone.
The anonymous collaborator
The anonymous CVS is a vital tool for fulfilling the "release early and often"
concept advocated by Eric Raymond. Any user anxious to try the latest version
of a program can extract it from the CVS, discover bugs and communicate
them, even in the form of patches with the correction. And can examine the
full history of the development.
Let's look at a bit of the mechanics. An advanced user wishes to obtain the
latest version of the module mod from an anonymously accessible repository
in progs.org, directory /var/lib/cvs and protocol pserver. The first
time he will declare his intention to enter:
cvs -d:pserver:anonymous@progs.org:/var/lib/cvs login
If a password is requested, it will be anonymous user (usually the carriage
return), which will be registered in a local file (this operation is not really
necessary for anonymous access, but the program will complain if the file with
the password does not exist). Next, the important thing is obtain the first copy
of the module:
cvs -d:pserver:anonymous@progs.org:/var/lib/cvs co mod
This will create a directory mod with all of the module's files and directories
and some metadata (contents in subdirectories called CVS), which will allow,
among other things, not having to repeat the information already provided.
Our advanced user will enter the created directory, generate the package and
test:
cd mod ./configure make make install ...
When he wishes to obtain a new version, he will simply update his copy wit-
hin mod.