NAME

       File::ChangeNotify::Watcher - Base class for all watchers

VERSION

       version 0.24

SYNOPSIS

           my $watcher =
               File::ChangeNotify->instantiate_watcher
                   ( directories => [ '/my/path', '/my/other' ],
                     filter      => qr/\.(?:pm|conf|yml)$/,
                     exclude     => ['t', 'root', qr(/(?!\.)[^/]+$)],
                   );

           if ( my @events = $watcher->new_events() ) { ... }

           # blocking
           while ( my @events = $watcher->wait_for_events() ) { ... }

DESCRIPTION

       A "File::ChangeNotify::Watcher" class monitors a directory for changes made to any file.
       You can provide a regular expression to filter out files you are not interested in. It
       handles the addition of new subdirectories by adding them to the watch list.

       Note that the actual granularity of what each watcher subclass reports may vary across
       subclasses. Implementations that hook into some sort of kernel event interface (Inotify,
       for example) have much better knowledge of exactly what changes are happening than one
       implemented purely in userspace code (like the Default subclass).

       By default, events are returned in the form File::ChangeNotify::Event objects, but this
       can be overridden by providing an "event_class" attribute to the constructor.

       The watcher can operate in a blocking/callback style, or you can simply ask it for a list
       of new events as needed.

METHODS

   File::ChangeNotify::Watcher::Subclass->new(...)
       This method creates a new watcher. It accepts the following arguments:

       •   directories => $path

       •   directories => \@paths

           This argument is required. It can be either one or many paths which should be watched
           for changes.

       •   filter => qr/.../

           This is an optional regular expression that will be used to check if a file is of
           interest. This filter is only applied to files.

           By default, all files are included.

       •   exclude => [...]

           An optional list of paths to exclude. This list can contain either plain strings or
           regular expressions. If you provide a string it should contain the complete path to be
           excluded.

           The paths can be either directories or specific files. If the exclusion matches a
           directory, all of its files and subdirectories are ignored.

       •   follow_symlinks => $bool

           By default, symlinks are ignored. Set this to true to follow them.

           If this symlinks are being followed, symlinks to files and directories will be
           followed. Directories will be watched, and changes for directories and files reported.

       •   sleep_interval => $number

           For watchers which call "sleep" to implement the "$watcher->wait_for_events()" method,
           this argument controls how long it sleeps for. The value is a number in seconds.

           The default is 2 seconds.

       •   event_class => $class

           This can be used to change the class used to report events. By default, this is
           File::ChangeNotify::Event.

   $watcher->wait_for_events()
       This method causes the watcher to block until it sees interesting events, and then return
       them as a list.

       Some watcher subclasses may implement blocking as a sleep loop, while others may actually
       block.

   $watcher->new_events()
       This method returns a list of any interesting events seen since the last time the watcher
       checked.

   $watcher->sees_all_events()
       If this is true, the watcher will report on all events.

       Some watchers, like the Default subclass, are not smart enough to track things like a file
       being created and then immediately deleted, and can only detect changes between snapshots
       of the file system.

       Other watchers, like the Inotify subclass, see all events that happen and report on them.

AUTHOR

       Dave Rolsky <autarch@urth.org>

COPYRIGHT AND LICENSE

       This software is Copyright (c) 2013 by Dave Rolsky.

       This is free software, licensed under:

         The Artistic License 2.0 (GPL Compatible)