inotifywait(1) — Linux manual page

NAME | SYNOPSIS | DESCRIPTION | OUTPUT | OPTIONS | EXIT STATUS | EVENTS | EXAMPLES | BUGS | AUTHORS | SEE ALSO | COLOPHON

inotifywait(1)           General Commands Manual          inotifywait(1)

NAME         top

       inotifywait - wait for changes to files using inotify

SYNOPSIS         top

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

DESCRIPTION         top

       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         top

       inotifywait will output diagnostic information on standard error
       and event information on standard output.  The event output can
       be configured, 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         top

       -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 relative 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.

       -P, --no-dereference
              Do not follow symlinks.

       -r, --recursive
              Watch all subdirectories of any directories passed as
              arguments.  Watches will be set up recursively to an
              unlimited depth.  Symbolic 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 subdirectory, 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 a negative value (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 specified 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.

       --no-newline
              Don't print newline symbol after user-specified format 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.  Otherwise, 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).

       %0     Replaced with NUL.

       %n     Replaced with Line Feed.

EXIT STATUS         top

       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         top

       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 implemented 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
              move 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         top

   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

   Example 4
       Enforce file permissions in directory `~/test'

       inotifywait -qmr -e 'moved_to,create' --format '%w%f%0' --no-newline ~/test |\
           while IFS= read -r -d '' file
           do
              chmod -v a+rX "$file"
           done

BUGS         top

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

       It is assumed the inotify event queue will never overflow.

AUTHORS         top

       inotifywait was started by Rohan McGovern, and is currently
       maintained by Eric Curtin and Radu Voicilas.
       https://www.openhub.net/p/inotify-tools/contributors/summary
       gives you a more complete list of contributors.

       inotifywait is part of inotify-tools.  The inotify-tools website
       is located at:
       https://github.com/inotify-tools/inotify-tools/wiki 

SEE ALSO         top

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

COLOPHON         top

       This page is part of the inotify-tools (command-line programs
       providing a simple interface to inotify) project.  Information
       about the project can be found at 
       ⟨https://github.com/rvoicilas/inotify-tools/wiki⟩.  If you have a
       bug report for this manual page, send it to
       inotify-tools-general@lists.sourceforge.net.  This page was
       obtained from the project's upstream Git repository
       ⟨https://github.com/rvoicilas/inotify-tools.git⟩ on 2020-12-18.
       (At that time, the date of the most recent commit that was found
       in the repository was 2020-12-08.)  If you discover any rendering
       problems in this HTML version of the page, or you believe there
       is a better or more up-to-date source for the page, or you have
       corrections or improvements to the information in this COLOPHON
       (which is not part of the original manual page), send a mail to
       man-pages@man7.org

inotifywait 3.20.11.0          2020-05-16                 inotifywait(1)

Pages that refer to this page: inotifywatch(1)inotify(7)