SVN error when trying to commit to remote host

I'm using svn on OS X, and am able to check items out of the repository of an svn server on my university campus (I am at home). I am now trying to commit files from my local working directory. I use the following command:

svn commit -m "First commit" file://hostname.ac.uk/directory/project/

where hostname is the same as I use to successfully check out items. However, the following error message is returned:

svn: Must give local path (not URL) as the target of a commit

It would be worth knowing that I have never committed anything to svn before. I wondered if the mes开发者_C百科sage implied that to commit I have to be physically connected to the svn server, i.e. on campus?

Specify your local working directory as the last parameter (. if you are already in it). It will know what remote location to commit to by itself.