Mail::...:Flock(3pm)

📦
version 4.02 · 9 versions
, in ubuntu stonking

💖 Mail::Box::Locker::Flock 💖

okay bestie, welcome to Mail::...:Flock(3pm) — that's the User Contributed Perl Documentation corner of the internet, and today we're locking folders with the actual kernel. obsessed. 🦋

✨ NAME ✨

Mail::Box::Locker::Flock — lock a folder using kernel file-locking 🔒

🌸 INHERITANCE 🌸

it's giving family tree, and the lineage is immaculate:

Mail::Box::Locker::Flock
  is a Mail::Box::Locker
  is a Mail::Reporter

🎀 SYNOPSIS 🎀

See the generic Mail::Box::Locker interface

literally that's it, it just says go read the generic interface. no notes. 💅

⭐ DESCRIPTION ⭐

The ::Flock object locks the folder by creating an exclusive lock on the file using the kernel's flock facilities. Big main-character move: that lock is created on a separate file-handle to the folder file, so not the handle which is reading. two handles, zero drama. ✨

🚨 real talk though: file locking does not work in some situations — for instance, operating systems that do not support flock. if that's your OS, this whole vibe is just not happening, sorry bestie. 😭

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.

the defaults table, served fresh, every single one of them:

 -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  'FLOCK'
  timeout  Mail::Box::Locker  10

and what each one takes:

  • 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() — Acquire a lock on the folder. Improves base, 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 💀

the "things went sideways" section. buckle up.

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(). 😭

Warning: folder $name already flocked. The folder is already locked, but you attempt to lock it again. The behavior of double flock's is platform dependent, and therefore should not be attempted. The second lock is ignored (but the unlock isn't). Cast by lock(). 🙈

Fault: unable to check lock file $file for $folder: $! To check whether the $file is used to flock a $folder, the file must be opened. Apparently this fails, which does not mean that the folder is locked neither that it is unlocked. Cast by isLocked(). 🫠

Fault: unable to open flock file $file for $folder: $! For flock-ing a $folder it must be opened, which does not succeed for the specified reason. Cast by lock(). 💔

Fault: will never get a flock at $file for $folder: $! Tried to flock the $folder, but it did not succeed. The error code received from the OS indicates that it will not succeed ever, so we do not need to try again. Cast by lock(). periodt, it's over. ✋

👑 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.

and that's the whole page bestie, perl v5.40.1, dated 2026-05-09 — she's a Mail::...:Flock(3pm) girlie through and through. go lock something (safely). 💖✨🎀

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