Getting PKGBUILDs from SVN
The entire SVN repo is huge. Not only will it take an obscene amount of disk space, but it will also tax the archlinux.org server for you to download it. Do not download the whole repo, only follow the instructions below.
If you abuse this service, your address may be blocked.
Never use the public SVN for any sort of scripting.
svn checkout -N svn://archlinux.org/home/svn-packages
This creates a directory named "svn-packages" which contains nothing. It does, however, know that it is an svn checkout.
Checkout a package
cd svn-packages svn update package-name
This will pull the package you requested into your checkout. From now on, any time you `svn update` at the top level, this will be updated as well.
Updating all packages
cd svn-packages svn update
Checkout an older revision of a package
cd svn-packages svn log
Find out the revision you want by examining the history
svn update -r1729 package-name
This will update an existing working copy of package-name to r1729