FUSER(1)			 User Commands			      FUSER(1)



NAME
       fuser - identify processes using files or sockets

SYNOPSIS
       fuser [-fuv] [-a|-s] [-4|-6] [-c|-m|-n space] [ -k [-i] [-M] [-w]
       [-SIGNAL] ] name ...
       fuser -l
       fuser -V

DESCRIPTION
       fuser displays the PIDs of processes using the specified files or  file
       systems.	  In the default display mode, each file name is followed by a
       letter denoting the type of access:

	      c	     current directory.
	      e	     executable being run.
	      f	     open file.	 f is omitted in default display mode.
	      F	     open file for writing.  F is omitted in  default  display
		     mode.
	      r	     root directory.
	      m	     mmap'ed file or shared library.

       fuser  returns a non-zero return code if none of the specified files is
       accessed or in case of a fatal error.  If at least one access has  been
       found, fuser returns zero.

       In  order  to  look  up processes using TCP and UDP sockets, the corre-
       sponding name space has to be selected with the -n option.  By  default
       fuser  will look in both IPv6 and IPv4 sockets.	To change the default,
       behavior, use the -4 and -6 options.  The socket(s) can be specified by
       the  local  and	remote	port,  and the remote address.	All fields are
       optional, but commas in front of missing fields must be present:

       [lcl_port][,[rmt_host][,[rmt_port]]]

       Either symbolic or numeric values can be used for IP addresses and port
       numbers.

       fuser  outputs  only  the  PIDs	to  stdout, everything else is sent to
       stderr.

OPTIONS
       -a, --all
	      Show all files specified on the command line.  By default,  only
	      files that are accessed by at least one process are shown.

       -c     Same as -m option, used for POSIX compatibility.

       -f     Silently ignored, used for POSIX compatibility.

       -k, --kill
	      Kill processes accessing the file.  Unless changed with -SIGNAL,
	      SIGKILL is sent.	An fuser process never kills itself,  but  may
	      kill  other  fuser  processes.   The  effective  user  ID of the
	      process executing fuser is  set  to  its	real  user  ID	before
	      attempting to kill.

       -i, --interactive
	      Ask  the	user  for  confirmation before killing a process. This
	      option is silently ignored if -k is not present too.

       -l, --list-signals
	      List all known signal names.

       -m NAME, --mount NAME
	      NAME specifies a file on a mounted file system or a block device
	      that  is	mounted.   All	processes accessing files on that file
	      system are listed.  If a directory  file	is  specified,	it  is
	      automatically  changed  to  NAME/.   to use any file system that
	      might be mounted on that directory.

       -M --ismountpoint
	      Request will be fulfilled only if NAME specifies	a  mountpoint.
	      This  is	an invaluable seatbelt which prevents you from killing
	      the machine if NAME happens to not be a filesystem.

       -w     Kill only processes which have write  access.   This  option  is
	      silently ignored if -k is not present too.

       -n SPACE, --namespace SPACE
	      Select  a	 different  name  space.   The	name spaces file (file
	      names, the default), udp (local UDP ports), and tcp  (local  TCP
	      ports)  are supported.  For ports, either the port number or the
	      symbolic name can be specified.  If there is no  ambiguity,  the
	      shortcut notation name/space (e.g. 80/tcp) can be used.

       -s, --silent
	      Silent  operation.  -u and -v are ignored in this mode.  -a must
	      not be used with -s.

       -SIGNAL
	      Use the specified signal instead of SIGKILL  when	 killing  pro-
	      cesses.  Signals can be specified either by name (e.g.  -HUP) or
	      by number (e.g.  -1).  This option is silently ignored if the -k
	      option is not used.

       -u, --user
	      Append the user name of the process owner to each PID.

       -v, --verbose

	      Verbose  mode.   Processes  are  shown  in a ps-like style.  The
	      fields PID, USER and COMMAND are similar to  ps.	 ACCESS	 shows
	      how  the process accesses the file.  Verbose mode will also show
	      when a particular file is being access as a  mount  point,  knfs
	      export  or  swap	file.  In this case kernel is shown instead of
	      the PID.

       -V, --version
	      Display version information.

       -4, --ipv4
	      Search only for IPv4 sockets.  This option must not be used with
	      the -6 option and only has an effect with the tcp and udp names-
	      paces.

       -6, --ipv6
	      Search only for IPv6 sockets.  This option must not be used with
	      the -4 option and only has an effect with the tcp and udp names-
	      paces.

       -      Reset all options and set the signal back to SIGKILL.

FILES
       /proc  location of the proc file system

EXAMPLES
       fuser -km /home
	      kills all processes accessing the file system /home in any way.

       if fuser -s /dev/ttyS1; then :; else something; fi
	      invokes something if no other process is using /dev/ttyS1.

       fuser telnet/tcp
	      shows all processes at the (local) TELNET port.

RESTRICTIONS
       Processes accessing the same file or file system several times  in  the
       same way are only shown once.

       If the same object is specified several times on the command line, some
       of those entries may be ignored.

       fuser may only be able to gather partial information  unless  run  with
       privileges.   As	 a consequence, files opened by processes belonging to
       other users may not be listed and  executables  may  be	classified  as
       mapped only.

       Installing  fuser SUID root will avoid problems associated with partial
       information, but may be undesirable for security and privacy reasons.

       udp and tcp name spaces, and UNIX domain sockets can't be searched with
       kernels older than 1.3.78.

       Accesses by the kernel are only shown with the -v option.

       The  -k	option	only  works  on processes.  If the user is the kernel,
       fuser will print an advice, but take no action beyond that.

BUGS
       fuser -m /dev/sgX will show (or kill with the -k flag)  all  processes,
       even  if	 you  don't  have  that device configured.  There may be other
       devices it does this for too.

       fuser cannot report on any processes that it doesn't have permission to
       look at the file descriptor table for.  The most common time this prob-
       lem occurs is when looking for TCP or UDP sockets when running fuser as
       a non-root user.	 In this case fuser will report no access

       The  mount  -m option will match any file within the save device as the
       specified file, use the -M option as well if you mean to	 specify  only
       the mount point.

SEE ALSO
       kill(1), killall(1), lsof(8), pkill(1), ps(1), kill(2).



psmisc				  2012-07-28			      FUSER(1)