inotifywait(1)                                                General Commands Manual                                               inotifywait(1)

NAME

       inotifywait - wait for changes to files using inotify

SYNOPSIS

       inotifywait [-hcmrq] [-e <event> ] [-t <seconds> ] [--format <fmt> ] [--timefmt <fmt> ] <file> [ ... ]

DESCRIPTION

       inotifywait  efficiently  waits  for  changes to files using Linux's inotify(7) interface.  It is suitable for waiting for changes to files
       from shell scripts.  It can either exit once an event occurs, or continually execute and output events as they occur.

OUTPUT

       inotifywait will output diagnostic information on standard error and event information on standard output.  The event output can be config-
       ured, but by default it consists of lines of the following form:

       watched_filename EVENT_NAMES event_filename

       watched_filename
              is the name of the file on which the event occurred.  If the file is a directory, a trailing slash is output.

       EVENT_NAMES
              are the names of the inotify events which occurred, separated by commas.

       event_filename
              is  output only when the event occurred on a directory, and in this case the name of the file within the directory which caused this
              event is output.

              By default, any special characters in filenames are not escaped in any way.  This can make the output of  inotifywait  difficult  to
              parse in awk scripts or similar.  The --csv and --format options will be helpful in this case.

OPTIONS

       -h, --help
              Output some helpful usage information.

       @<file>
              When  watching a directory tree recursively, exclude the specified file from being watched.  The file must be specified with a rela-
              tive or absolute path according to whether a relative or absolute path is given for watched directories.   If  a  specific  path  is
              explicitly both included and excluded, it will always be watched.

              Note: If you need to watch a directory or file whose name starts with @, give the absolute path.

       --fromfile <file>
              Read  filenames  to  watch  or exclude from a file, one filename per line.  If filenames begin with @ they are excluded as described
              above.  If <file> is `-', filenames are read from standard input.  Use this option if you need to watch too many files to pass in as
              command line arguments.

       -m, --monitor
              Instead  of  exiting  after  receiving a single event, execute indefinitely.  The default behaviour is to exit after the first event
              occurs.

       -d, --daemon
              Same as --monitor, except run in the background logging events to a file that must be specified by --outfile. Implies --syslog.

       -o, --outfile <file>
              Output events to <file> rather than stdout.

       -s, --syslog
              Output errors to syslog(3) system log module rather than stderr.

       -r, --recursive
              Watch all subdirectories of any directories passed as arguments.  Watches will be set up recursively to an  unlimited  depth.   Sym-
              bolic links are not traversed.  Newly created subdirectories will also be watched.

              Warning:  If  you  use  this  option  while watching the root directory of a large tree, it may take quite a while until all inotify
              watches are established, and events will not be received in this time.  Also, since one inotify watch will be established per subdi-
              rectory, it is possible that the maximum amount of inotify watches per user will be reached.  The default maximum is 8192; it can be
              increased by writing to /proc/sys/fs/inotify/max_user_watches.

       -q, --quiet
              If specified once, the program will be less verbose.  Specifically, it will not state when it has completed establishing all inotify
              watches.

              If specified twice, the program will output nothing at all, except in the case of fatal errors.

       --exclude <pattern>
              Do not process any events whose filename matches the specified POSIX extended regular expression, case sensitive.

       --excludei <pattern>
              Do not process any events whose filename matches the specified POSIX extended regular expression, case insensitive.

       -t <seconds>, --timeout <seconds>
              Exit if an appropriate event has not occurred within <seconds> seconds. If <seconds> is zero (the default), wait indefinitely for an
              event.

       -e <event>, --event <event>
              Listen for specific event(s) only.  The events which can be listened for are listed in the EVENTS section.  This option can be spec-
              ified more than once.  If omitted, all events are listened for.

       -c, --csv
              Output  in CSV (comma-separated values) format.  This is useful when filenames may contain spaces, since in this case it is not safe
              to simply split the output at each space character.

       --timefmt <fmt>
              Set a time format string as accepted by strftime(3) for use with the `%T' conversion in the --format option.

       --format <fmt>
              Output in a user-specified format, using printf-like syntax.  The event strings output are limited to  around  4000  characters  and
              will be truncated to this length.  The following conversions are supported:

       %w     This will be replaced with the name of the Watched file on which an event occurred.

       %f     When  an  event  occurs within a directory, this will be replaced with the name of the File which caused the event to occur.  Other-
              wise, this will be replaced with an empty string.

       %e     Replaced with the Event(s) which occurred, comma-separated.

       %Xe    Replaced with the Event(s) which occurred, separated by whichever character is in the place of `X'.

       %T     Replaced with the current Time in the format specified by the --timefmt option, which should be a format string suitable for passing
              to strftime(3).

EXIT STATUS

       0      The program executed successfully, and an event occurred which was being listened for.

       1      An  error  occurred in execution of the program, or an event occurred which was not being listened for.  The latter generally occurs
              if something happens which forcibly removes the inotify watch, such as a watched file being deleted or the filesystem  containing  a
              watched file being unmounted.

       2      The -t option was used and an event did not occur in the specified interval of time.

EVENTS

       The following events are valid for use with the -e option:

       access A watched file or a file within a watched directory was read from.

       modify A watched file or a file within a watched directory was written to.

       attrib The  metadata  of  a  watched  file  or a file within a watched directory was modified.  This includes timestamps, file permissions,
              extended attributes etc.

       close_write
              A watched file or a file within a watched directory was closed, after being opened in writeable mode.   This  does  not  necessarily
              imply the file was written to.

       close_nowrite
              A watched file or a file within a watched directory was closed, after being opened in read-only mode.

       close  A  watched file or a file within a watched directory was closed, regardless of how it was opened.  Note that this is actually imple-
              mented simply by listening for both close_write and close_nowrite, hence all close events received will be output as one  of  these,
              not CLOSE.

       open   A watched file or a file within a watched directory was opened.

       moved_to
              A  file  or  directory  was moved into a watched directory.  This event occurs even if the file is simply moved from and to the same
              directory.

       moved_from
              A file or directory was moved from a watched directory.  This event occurs even if the file is simply moved from  and  to  the  same
              directory.

       move   A  file  or directory was moved from or to a watched directory.  Note that this is actually implemented simply by listening for both
              moved_to and moved_from, hence all close events received will be output as one or both of these, not MOVE.

       move_self
              A watched file or directory was moved. After this event, the file or directory is no longer being watched.

       create A file or directory was created within a watched directory.

       delete A file or directory within a watched directory was deleted.

       delete_self
              A watched file or directory was deleted.  After this event the file or directory is no longer being watched.  Note that  this  event
              can occur even if it is not explicitly being listened for.

       unmount
              The  filesystem  on  which  a  watched file or directory resides was unmounted.  After this event the file or directory is no longer
              being watched.  Note that this event can occur even if it is not explicitly being listened to.

EXAMPLES

   Example 1
       Running inotifywait at the command-line to wait for any file in the `test' directory to  be  accessed.   After  running  inotifywait,  `cat
       test/foo' is run in a separate console.

       % inotifywait test
       Setting up watches.
       Watches established.
       test/ ACCESS foo

   Example 2
       A short shell script to efficiently wait for httpd-related log messages and do something appropriate.

       #!/bin/sh
       while inotifywait -e modify /var/log/messages; do
         if tail -n1 /var/log/messages | grep httpd; then
           kdialog --msgbox "Apache needs love!"
         fi
       done

   Example 3
       A custom output format is used to watch `~/test'.  Meanwhile, someone runs `touch ~/test/badfile; touch ~/test/goodfile; rm ~/test/badfile'
       in another console.

       % inotifywait -m -r --format '%:e %f' ~/test
       Setting up watches.  Beware: since -r was given, this may take a while!
       Watches established.
       CREATE badfile
       OPEN badfile
       ATTRIB badfile
       CLOSE_WRITE:CLOSE badfile
       CREATE goodfile
       OPEN goodfile
       ATTRIB goodfile
       CLOSE_WRITE:CLOSE goodfile
       DELETE badfile

CAVEATS

       When using inotifywait, the filename that is outputted is not guaranteed to be up to date after a move because it  is  the  inode  that  is
       being  monitored.  Additionally,  none  of  the  observed  operations are guaranteed to have been performed on the filename inotifywait was
       instructed to monitor in cases when the file is known by several names in the filesystem.

BUGS

       There are race conditions in the recursive directory watching code which can cause events to be missed if they occur in a directory immedi-
       ately after that directory is created.  This is probably not fixable.

       It is assumed the inotify event queue will never overflow.

AUTHORS

       inotifywait is written and maintained by Rohan McGovern <rohan@mcgovern.id.au>.

       inotifywait is part of inotify-tools.  The inotify-tools website is located at: http://inotify-tools.sourceforge.net/

SEE ALSO

       inotifywatch(1), strftime(3), inotify(7)

inotifywait 3.14                                                  March 14, 2010                                                    inotifywait(1)