Automated versioning of files in file share?

We have a file share on a debian server which p开发者_C百科eople will be putting mostly small plain text, word, excel, pdf, misc, files into. We want to keep file level versioning of everything placed in that file share. We'd like all of the versioning to happen automatically in the background every time a change is made to a file.

What's the easiest open source way to do this? What's the best versioning system to do this with? Is there an automated versioning system like this out there somewhere?

I'm not asking for complete instructions. I'm just looking for recommendations or keywords to search with (other than "automatic versioning files" which didn't find me much).

We're already backing up the volume many times a day. We don't want to do volume snapshots etc. We're looking for some kind of automated file level versioning.

Update:

Using incron to autocommit changes in a folder:

http://andrew.mcmillan.net.nz/blog/using_incron_to_autoversion_a_directory

Thanks to using the new keyword "autoversioning" I found the above which I'm interested in. It's a script which is triggered from incron every time a file changes. One problem is incron isn't recursive.

I would try a versioned filesystem, such as ext3cow or nilfs. I have no experience with them, but they have always looked like a very interesting idea to me.

The SVNAutoVersioning directive to mod_dav_svn is one solution.