Get info. about files opened by processes

An open file may be a regular file, a directory, a block special file, a character special file, an executing text reference, a library, a stream or a network file (Internet socket, NFS file or UNIX domain socket.) A specific file or all the files in a file system may be selected by path.

So If you want to know about what processes are currently hund on to your directory /mnt/cdrom