The pure-data project's CVS data is in read-only mode, so the project may have switched over to another source-code-management system. To check, visit the Project Summary Page for pure-data and see if the menubar lists a newer code repository, such as SVN or Git.
The CVS data can be accessed as follows.
You can run a per-module CVS checkout via pserver protocol:
cvs -z3 -d:pserver:anonymous@a.cvs.sourceforge.net:/cvsroot/pure-data co -P Attic
cvs -z3 -d:pserver:anonymous@a.cvs.sourceforge.net:/cvsroot/pure-data co -P Framestein
cvs -z3 -d:pserver:anonymous@a.cvs.sourceforge.net:/cvsroot/pure-data co -P abstractions
cvs -z3 -d:pserver:anonymous@a.cvs.sourceforge.net:/cvsroot/pure-data co -P doc
cvs -z3 -d:pserver:anonymous@a.cvs.sourceforge.net:/cvsroot/pure-data co -P extensions
cvs -z3 -d:pserver:anonymous@a.cvs.sourceforge.net:/cvsroot/pure-data co -P externals
cvs -z3 -d:pserver:anonymous@a.cvs.sourceforge.net:/cvsroot/pure-data co -P htdocs
cvs -z3 -d:pserver:anonymous@a.cvs.sourceforge.net:/cvsroot/pure-data co -P packages
cvs -z3 -d:pserver:anonymous@a.cvs.sourceforge.net:/cvsroot/pure-data co -P pd
cvs -z3 -d:pserver:anonymous@a.cvs.sourceforge.net:/cvsroot/pure-data co -P scripts
cvs -z3 -d:pserver:anonymous@a.cvs.sourceforge.net:/cvsroot/pure-data co -P supercollider
cvs -z3 -d:pserver:anonymous@a.cvs.sourceforge.net:/cvsroot/pure-data co -P xgui
You can view a list of files or copy all the CVS repository data via rsync (the 1st command lists the files, the 2nd copies):
rsync -a a.cvs.sourceforge.net::cvsroot/pure-data/
rsync -ai a.cvs.sourceforge.net::cvsroot/pure-data/ /my/local/dest/dir/
If you are a project admin for pure-data, you can request that this page redirect to another repo on your project by submitting a support request.