[2005] Shared file used by who?

In my application I need to overwrite some shared files with a new version of them so, is it possible to know if a shared file is in use and by who? I need to check that before overwriting them.

Thanks

You can test to see if a file is in use with this code

However I am not aware of a specific way to be able to tell WHO is locking the file. I know there are ways to keep track of that, I have seen it in server admin software, but I don't know of any specific way to do it from a client workstation in VB.