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NAME

       incrontab - tables for driving inotify cron (incron)

DESCRIPTION

       An incrontab file contains instructions to the incrond(8) daemon of the
       general form: "run this command on these file events".  There  are  two
       categories  of  tables:  system  tables (with root privileges) and user
       tables (with user privileges).

       System tables are (by default) located in /etc/incron.d  and  may  have
       any  names. Each system table exists separately inside incron and their
       watches never collide.

       Each user has their own table, and commands in any given incrontab will
       be  executed  as the user who owns the incrontab. System users (such as
       apache, postfix, nobody etc.) may have their own incrontab.

       incrontab files are read when the incrond(8) daemon  starts  and  after
       any change (incrontab file are being hooked when incrond is running).

       Blank lines are ignored. The general line format is the following:

       <path> <mask> <command>

       Where  path  is  an absolute filesystem path, mask is an event mask (in
       symbolic or numeric form) and command  is  an  executable  file  (or  a
       script)  with  its  arguments.  See  bellow for event mask symbols. The
       executable file may be noted as an absolute path or only  as  the  name
       itself (PATH locations are examined).

       Please  remember  that  the  same  path  may  occur only once per table
       (otherwise only the first occurrence takes effect and an error  message
       is emitted to the system log).

EVENT SYMBOLS

       These basic event mask symbols are defined:

       IN_ACCESS           File was accessed (read) (*)
       IN_ATTRIB           Metadata changed (permissions, timestamps, extended
       attributes, etc.) (*)
       IN_CLOSE_WRITE      File opened for writing was closed (*)
       IN_CLOSE_NOWRITE    File not opened for writing was closed (*)
       IN_CREATE           File/directory created in watched directory (*)
       IN_DELETE           File/directory deleted from watched directory (*)
       IN_DELETE_SELF           Watched file/directory was itself deleted
       IN_MODIFY           File was modified (*)
       IN_MOVE_SELF        Watched file/directory was itself moved
       IN_MOVED_FROM       File moved out of watched directory (*)
       IN_MOVED_TO         File moved into watched directory (*)
       IN_OPEN             File was opened (*)

       When monitoring a directory, the events marked  with  an  asterisk  (*)
       above  can  occur  for  files  in the directory, in which case the name
       field in the returned event data identifies the name of the file within
       the directory.

       The  IN_ALL_EVENTS  symbol is defined as a bit mask of all of the above
       events. Two additional convenience symbols  are  IN_MOVE,  which  is  a
       combination  of  IN_MOVED_FROM  and  IN_MOVED_TO,  and  IN_CLOSE  which
       combines IN_CLOSE_WRITE and IN_CLOSE_NOWRITE.

       The following further symbols can be specified in the mask:

       IN_DONT_FOLLOW      Don’t dereference pathname if it is a symbolic link
       IN_ONESHOT          Monitor pathname for only one event
       IN_ONLYDIR          Only watch pathname if it is a directory

       Additionally,  there  is  a  symbol which doesn’t appear in the inotify
       symbol set. It it IN_NO_LOOP. This symbol  disables  monitoring  events
       until  the  current  one is completely handled (until its child process
       exits).

WILDCARDS

       The following wildards may be used inside command specification:

       $$   dollar sign
       $@   watched filesystem path (see above)
       $#   event-related file name
       $%   event flags (textually)
       $&   event flags (numerically)

EXAMPLE

       These are some example rules which can be used in an incrontab file:

       /tmp IN_ALL_EVENTS abcd $@/$# $%

       /usr/bin IN_ACCESS,IN_NO_LOOP abcd $#

       /home IN_CREATE /usr/local/bin/abcd $#

       /var/log 12 abcd $@/$#

       The first line monitors all events on the /tmp directory. When an event
       occurs  it  runs  a application called ’abcd’ with the full path of the
       file as the first arguments and the event flags as the second one.

       The second line monitors accesses (readings) on the /usr/bin directory.
       The  application  ’abcd’  is run as a handler and the appropriate event
       watch is disabled until the program finishes. The  file  name  (without
       the directory path) is passed in as an argument.

       The  third example is used for monitoring the /home directory for newly
       create files or directories (it practically means an event is sent when
       a new user is added). This event is processed by a program specified by
       an absolute path.

       And the final line shows how to  use  numeric  event  mask  instead  of
       textual    one.    The    value    12    is   exactly   the   same   as
       IN_ATTRIB,IN_CLOSE_WRITE.

SEE ALSO

       incrond(8), incrontab(1), incron.conf(5)

AUTHOR

       Lukas    Jelinek    <lukas@aiken.cz>    (please    report    bugs    to
       http://bts.aiken.cz or <bugs@aiken.cz>).

COPYING

       This  program  is  free  software. It can be used, redistributed and/or
       modified under the terms of the GNU General Public License, version  2.