1File::Flock(3)        User Contributed Perl Documentation       File::Flock(3)
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NAME

6        File::Flock - file locking with flock
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SYNOPSIS

9        use File::Flock;
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11        lock($filename);
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13        lock($filename, 'shared');
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15        lock($filename, undef, 'nonblocking');
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17        lock($filename, 'shared', 'nonblocking');
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19        unlock($filename);
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21        lock_rename($oldfilename, $newfilename)
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23        my $lock = new File::Flock '/somefile';
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25        $lock->unlock();
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27        $lock->lock_rename('/new/file');
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29        forget_locks();
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DESCRIPTION

32       Lock files using the flock() call.  If the file to be locked does not
33       exist, then the file is created.  If the file was created then it will
34       be removed when it is unlocked assuming it's still an empty file.
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36       Locks can be created by new'ing a File::Flock object.  Such locks are
37       automatically removed when the object goes out of scope.  The unlock()
38       method may also be used.
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40       lock_rename() is used to tell File::Flock when a file has been renamed
41       (and thus the internal locking data that is stored based on the
42       filename should be moved to a new name).  unlock() the new name rather
43       than the original name.
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45       Locks are released on process exit when the process that created the
46       lock exits.  Subprocesses that exit do not remove locks.  Use
47       forget_locks() or POSIX::_exit() to prevent unlocking on process exit.
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SEE ALSO

50       See File::Flock::Subprocess for a variant that uses a subprocess to
51       hold the locks so that the locks survive when the parent process forks.
52       See File::Flock::Forking for a way to automatically choose between
53       File::Flock and File::Flock::Subprocess.
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LICENSE

56       Copyright (C) 1996-2012 David Muir Sharnoff <cpan@dave.sharnoff.org>
57       Copyright (C) 2013 Google, Inc.  This module may be used/copied/etc on
58       the same terms as Perl itself.
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PACKAGERS

61       File::Flock is packaged for Fedora by Emmanuel Seyman
62       <emmanuel.seyman@club-internet.fr>.
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66perl v5.38.0                      2023-07-20                    File::Flock(3)