Thread::Queue - thread-safe queues
use Thread::Queue;
my $q = new Thread::Queue;
$q->enqueue("foo", "bar");
my $foo = $q->dequeue; # The "bar" is still in the queue.
my $foo = $q->dequeue_nb; # returns "bar", or undef if the queue was empty
my $left = $q->pending; # returns the number of items still in the queue
A queue, as implemented by Thread::Queue is a thread-safe
data structure much like a list. 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).
new function creates a new empty queue.
enqueue method adds a list of scalars on to the end of the queue.
The queue will grow as needed to accommodate the list.
dequeue method removes a scalar from the head of the queue and
returns it. If the queue is currently empty, dequeue will block the
thread until another thread enqueues a scalar.
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 method returns the number of items still in the queue.