fuser

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NAME

       fuser - identify processes using files


SYNOPSIS

       fuser [-a|-s] [-signal] [-kmuv] filename ...  [-] [-sig-
       nal] [-kmuv] filename ...
       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.

              r      root directory.

              m      mmap'ed file or shared library.

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


OPTIONS

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

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

       -l     List all known signal names.

       -m     filename  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  filename/. to use any file system that
              might be mounted on that directory.

       -s     Silent operation. -a, -u and -v are ignored in this
              mode.

       -signal
              use  the  specified  signal instead of SIGKILL when
              killing processes. Signals can be specified  either
              by name (e.g. -HUP) or by number (e.g. -1).

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

       -v     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.

       -V     Display version information.

       -      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.


RESTRICTIONS

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

       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 secu-
       rity and privacy reasons.


AUTHOR

       Werner Almesberger <werner.almesberger@lrc.di.epfl.ch>


SEE ALSO

       kill(1), killall(1), ps(1), kill(2)
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