Apologies if this has been discussed previously... I did a stack overflow and google search but probably didn't use the right keywords.
Anyway, is there an easy way to determine what files are open on Mac OS X? I had an issue in which I could not unmount a firewire HD until I closed all running apps. Turns out keychain access had a reference to a file on the HD, but it begged the question: how to find out what files are open and what app (or apps) has the file open?
Thanks in advance and again apologies if this has been covered previously.