Every once in a while you find a document that cannot be deleted or a disk volume that cannot be ejected because the file is locked by a process that is currently running.
For example, yesterday one of our users could not eject the AllBookmarks disk image:
The best way to find what process is using this file is to use lsof command. For example,
lsof | grep AllBookmarks
The output will display a list of processes that a related to AllBookmarks:
As you can see in this picture, the process with id 913 is using the disk image volume. Now that you have the process id you can force this process to quit by using Activity Monitor application or simply by running kill 913 in the Terminal window.
