Mail::Box::Locker::NFS(3)                  User Contributed Perl Documentation


NAME
       Mail::Box::Locker::NFS - lock a folder with a separate file, NFS-safe

INHERITANCE
        Mail::Box::Locker::NFS
          is a Mail::Box::Locker
          is a Mail::Reporter

SYNOPSIS
         See Mail::Box::Locker

DESCRIPTION
       Like the "::DotLock" locker, but then in an NFS-safe fashion.  Over
       NFS, the creation of a file is not atomic.  The "::DotLock" locker
       depends on an atomic "open" system call, hence in not usable to lock a
       folder which accessed over NFS.  The "::NFS" locker is therefore more
       complicated (so therefore slower), but will work for NFS --and for
       local disks as well.

       Extends "DESCRIPTION" in Mail::Box::Locker.

METHODS
       Extends "METHODS" in Mail::Box::Locker.

   Constructors
       Extends "Constructors" in Mail::Box::Locker.

       $class->new(%options)
           Inherited, see "METHODS" in Mail::Box::Locker

            -Option --Defined in       --Default
             expires  Mail::Box::Locker  1 hour
             file     Mail::Box::Locker  undef
             folder   Mail::Box::Locker  <C<undef>>
             method   Mail::Box::Locker  'NFS'
             timeout  Mail::Box::Locker  10

           expires => $seconds
           file => $file
           folder => $folder
           method => $name|CLASS|\@names
           timeout => $seconds|'NOTIMEOUT'

   Attributes
       Extends "Attributes" in Mail::Box::Locker.

       $obj->expires( [SECONDS] )
           Inherited, see "Attributes" in Mail::Box::Locker

       $obj->filename( [$filename] )
           Inherited, see "Attributes" in Mail::Box::Locker

       $obj->folder( [$folder] )
           Inherited, see "Attributes" in Mail::Box::Locker

       $obj->name()
           Inherited, see "Attributes" in Mail::Box::Locker

       $obj->timeout( [SECONDS] )
           Inherited, see "Attributes" in Mail::Box::Locker

   Locking
       Extends "Locking" in Mail::Box::Locker.

       $obj->hasLock()
           Inherited, see "Locking" in Mail::Box::Locker

       $obj->isLocked()
           Inherited, see "Locking" in Mail::Box::Locker

       $obj->lock()
           Inherited, see "Locking" in Mail::Box::Locker

       $obj->unlock()
           Inherited, see "Locking" in Mail::Box::Locker

   Error handling
       Extends "Error handling" in Mail::Box::Locker.

       $obj->AUTOLOAD()
           Inherited, see "Error handling" in Mail::Reporter

       $obj->notImplemented()
           Inherited, see "Error handling" in Mail::Reporter

   Cleanup
       Extends "Cleanup" in Mail::Box::Locker.

       $obj->DESTROY()
           Inherited, see "Cleanup" in Mail::Box::Locker

DIAGNOSTICS
       Error: class $package does not implement method $method.
           Fatal error: the specific $package (or one of its superclasses)
           does not implement this method where it should. This message means
           that some other related classes do implement this method however
           the class at hand does not.  Probably you should investigate this
           and probably inform the author of the package.  Cast by
           notImplemented()

       Fault: couldn't remove lockfile $file: $!
           Cast by unlock()

       Warning: folder $name already locked over NFS.
           Do not try to lock the folder when the application already has the
           lock: it will give you dead-locks.  Cast by lock()

       Warning: removed expired lockfile $file.
           A lock $file was found which was older than the expiration period
           as specified with new(timeout).  The lock file was successfully
           removed.  Cast by lock()

       Fault: unable to remove expired lockfile $file: $!
           A lock file was found which was older than the expiration period as
           specified with the new(timeout) option.  It is impossible to remove
           that lock file, so we need to wait until it vanishes by some
           external cause.  Cast by lock()

SEE ALSO
       This module is part of Mail-Box version 4.02, built on April 10, 2026.
       Website: http://perl.overmeer.net/CPAN/

LICENSE
       For contributors see file ChangeLog.

       This software is copyright (c) 2001-2026 by Mark Overmeer.

       This is free software; you can redistribute it and/or modify it under
       the same terms as the Perl 5 programming language system itself.

perl v5.42.2                      2026-04-11         Mail::Box::Locker::NFS(3)