| Thread-Cancel documentation | Contained in the Thread-Cancel distribution. |
Thread::Cancel - Cancel (i.e., kill) threads
This document describes Thread::Cancel version 1.13
use Thread::Cancel 'SIGUSR1'; # Set the cancellation signal
use Thread::Cancel; # Defaults to 'KILL'
$thr->cancel(); # Cancel a thread
threads->cancel(); # Cancel all non-detached threads
threads->cancel($thr, $tid, ...); # Cancel multiple threads using
# objects or TIDs
This module adds cancellation capabilities for threads. Cancelled threads are
terminated using threads->exit(). The thread is then detached, and
hence automatically cleaned up.
Threads that are suspended using Thread::Suspend do not need to be resumed in order to be cancelled.
It is possible for a thread to cancel itself.
This module must be imported prior to any threads being created.
Cancellation is accomplished via a signal handler which is used by all threads
on which cancel operations are performed. The signal for this operation can
be specified when this module is declared, and defaults to SIGKILL.
Consequently, the application and its threads must not specify some other
handler for use with the cancel signal.
Declares this module, and defaults to using SIGKILL for cancel operations.
Declares this module, and uses the specified signal for cancel operations. Signals may be specified by the same names or (positive) numbers as supported by kill() ("kill SIGNAL, LIST" in perlfunc).
Cancels the threads.
Cancels all non-detached threads. This offers a clean way to exit a threaded application:
# Terminate all threads and exit
threads->cancel();
exit(0);
Cancels the threads specified by their objects or TIDs (for non-detached threads).
Subject to the limitations of "THREAD SIGNALLING" in threads.
Cancelled threads are automatically detached, so do not try to ->join()
or ->detach() a cancelled thread.
Detached threads can only be cancelled using their threads object:
$thr->detach();
$thr->cancel();
# or
threads->cancel($thr);
Threads that have finished execution are, for the most part, ignored by this module.
Thread::Cancel Discussion Forum on CPAN: http://www.cpanforum.com/dist/Thread-Cancel
Jerry D. Hedden, <jdhedden AT cpan DOT org>
Copyright 2006 - 2009 Jerry D. Hedden. All rights reserved.
This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.
| Thread-Cancel documentation | Contained in the Thread-Cancel distribution. |
package Thread::Cancel; { use strict; use warnings; our $VERSION = '1.13'; use threads 1.39; my $SIGNAL = 'KILL'; # Default cancellation signal sub import { my $class = shift; # Not used # Set the signal for cancel operations while (my $sig = shift) { $SIGNAL = $sig; } $SIGNAL =~ s/^SIG//; # Set up the cancel signal handler $SIG{$SIGNAL} = sub { threads->exit(); }; } sub threads::cancel { my ($class, @threads) = @_; if ($class eq 'threads') { if (@threads) { # Cancel specified list of threads @threads = grep { $_ } map { (ref($_) eq 'threads') ? $_ : threads->object($_) } @threads; } else { # Cancel all threads push(@threads, threads->list()); } } else { # Cancel a single thread push(@threads, $class); } # Cancel threads my $resumable = threads->can('resume'); foreach my $thr (@threads) { $thr->detach() if (! $thr->is_detached()); $thr->kill($SIGNAL); if ($resumable) { $thr->resume() if ($thr->is_suspended()); } } } } 1; __END__