I was not sure on the title for this post, but I bet everyone, at least once, needed to know which file is being modified at this exact moment in your filesystem/server.
Some days ago I noticed something was making my filesystem full. I cleared some gigas in logs from Diag Home but the space gone 100% very quickly. What is consuming the space?
1. Create a new file.
$ touch a.log
2. Find everything newer than this file.
$ find . -newer a.log
Here you go!
In my situation, after finding this, I noticed there was a session in a bug situation generating thousands of messages on trace file.
Killed the session, got part of the messages, cleared file. Issue solved.
Hope it helps!