The lsof command

The lsof (list open files) command returns the user processes that are actively using a file system. It is sometimes helpful in determining why a file system remains in use and cannot be unmounted.

The lsof command is available in Linux® distributions or by using anonymous ftp from lsof.itap.purdue.edu (cd to /pub/tools/unix/lsof). The inventor of the lsof command is Victor A. Abell (abe@purdue.edu), Purdue University Computing Center.