NAME
Thread::Queue::Any - thread-safe queues for any data-structure
SYNOPSIS
use Thread::Queue::Any;
my $q = Thread::Queue::Any->new;
$q->enqueue("foo", ["bar"], {"zoo"});
my ($foo,$bar,$zoo) = $q->dequeue;
my ($foo,$bar,$zoo) = $q->dequeue_nb;
my $left = $q->pending;
DESCRIPTION
*** A note of CAUTION ***
This module only functions on Perl versions 5.8.0-RC3 and later.
And then only when threads are enabled with -Dusethreads. It is
of no use with any version of Perl before 5.8.0-RC3 or without
threads enabled.
*************************
A queue, as implemented by Thread::Queue::Any
is a thread-safe data structure that inherits from Thread::Queue
. But unlike the standard Thread::Queue
, you can pass (a reference to) any data structure to the queue.
Apart from the fact that the parameters to enqueue
are considered to be a set that needs to be enqueued together and that dequeue
returns all of the parameters that were enqueued together, this module is a drop-in replacement for Thread::Queue
in every other aspect.
Any number of threads can safely add elements to the end of the list, or remove elements from the head of the list. (Queues don't permit adding or removing elements from the middle of the list).
CLASS METHODS
new
$queue = Thread::Queue::Any->new;
The new
function creates a new empty queue.
OBJECT METHODS
enqueue LIST
$queue->enqueue( 'string',$scalar,[],{} );
The enqueue
method adds a reference to all the specified parameters on to the end of the queue. The queue will grow as needed.
dequeue
($string,$scalar,$listref,$hashref) = $queue->dequeue;
The dequeue
method removes a reference from the head of the queue, dereferences it and returns the resulting values. If the queue is currently empty, dequeue
will block the thread until another thread enqueue
s.
dequeue_nb
($string,$scalar,$listref,$hashref) = $queue->dequeue;
The dequeue_nb
method, like the dequeue
method, removes a scalar from the head of the queue and returns it. Unlike dequeue
, though, dequeue_nb
won't block if the queue is empty, instead returning undef
.
pending
$pending = $queue->pending;
The pending
method returns the number of items still in the queue.
CAVEATS
Passing unshared values between threads is accomplished by serializing the specified values using Storable
when enqueuing and de-serializing the queued value on dequeuing. This allows for great flexibility at the expense of more CPU usage. It also limits what can be passed, as e.g. code references can not be serialized and therefore not be passed.
AUTHOR
Elizabeth Mattijsen, <liz@dijkmat.nl>.
Please report bugs to <perlbugs@dijkmat.nl>.
COPYRIGHT
Copyright (c) 2002 Elizabeth Mattijsen <liz@dijkmat.nl>. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.