OSX / Mac OS Empty Trash
Sometimes while deleting files from trash, mac os gives error that the file is in use. It is very difficult to track down the application that uses the file. The following commands can be of some help.
lsof | grep Trash
The above command shows you the application that is preventing the files from being deleted from trash.
Now you can always close the application and try again, however if there is still error or you cannot close the application that’s using the file to be deleted, you can again use the power of command line.
rm -Rf ~/.Trash/*
The above command clears the files from Trash.