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=head1 NAME |
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Coro::Signal - thread signals (binary semaphores) |
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=head1 SYNOPSIS |
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use Coro; |
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my $sig = new Coro::Signal; |
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$sig->wait; # wait for signal |
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# ... some other "thread" |
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$sig->send; |
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=head1 DESCRIPTION |
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This module implements signals/binary semaphores/condition variables |
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(basically all the same thing). You can wait for a signal to occur or send |
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it, in which case it will wake up one waiter, or it can be broadcast, |
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waking up all waiters. |
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It is recommended not to mix C<send> and C<broadcast> calls on the same |
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C<Coro::Signal> without some deep thinking: while it should work as |
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documented, it can easily confuse you :-> |
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You don't have to load C<Coro::Signal> manually, it will be loaded |
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automatically when you C<use Coro> and call the C<new> constructor. |
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=over 4 |
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=cut |
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package Coro::Signal; |
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use common::sense; |
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use Coro::Semaphore (); |
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our $VERSION = 6.57; |
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=item $sig = new Coro::Signal; |
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Create a new signal. |
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=item $sig->wait |
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Wait for the signal to occur (via either C<send> or C<broadcast>). Returns |
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immediately if the signal has been sent before. |
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=item $sig->wait ($callback) |
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If you pass a callback argument to C<wait>, it will not wait, but |
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immediately return. The callback will be called under the same conditions |
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as C<wait> without arguments would continue the thrad. |
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The callback might wake up any number of threads, but is I<NOT> allowed to |
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block (switch to other threads). |
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=item $sig->send |
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Send the signal, waking up I<one> waiting process or remember the signal |
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if no process is waiting. |
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=item $sig->broadcast |
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Send the signal, waking up I<all> waiting process. If no process is |
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waiting the signal is lost. |
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=item $sig->awaited |
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Return true when the signal is being awaited by some process. |
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=cut |
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#=item $status = $s->timed_wait ($timeout) |
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# |
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#Like C<wait>, but returns false if no signal happens within $timeout |
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#seconds, otherwise true. |
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# |
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#See C<wait> for some reliability concerns. |
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# |
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#=cut |
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#ub timed_wait { |
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# require Coro::Timer; |
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# my $timeout = Coro::Timer::timeout($_[1]); |
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# |
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# unless (delete $_[0][0]) { |
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# push @{$_[0][1]}, $Coro::current; |
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# &Coro::schedule; |
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# |
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# return 0 if $timeout; |
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# } |
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# |
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# 1 |
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# |
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1; |
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=back |
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=head1 AUTHOR/SUPPORT/CONTACT |
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Marc A. Lehmann <schmorp@schmorp.de> |
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http://software.schmorp.de/pkg/Coro.html |
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=cut |
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