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<h3 id="TOP">Index</h3>

<ul><li><a href="#NAME">NAME</a></li>
<li><a href="#CATEGORY">CATEGORY</a></li>
<li><a href="#SYNOPSIS">SYNOPSIS</a></li>
<li><a href="#METHODS">METHODS</a>
<ul><li><a href="#add_timer">add_timer</a></li>
<li><a href="#remove_timer">remove_timer</a>
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<h1 id="NAME">NAME</h1><p><a href="#TOP" class="toplink">Top</a></p>
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<p>SDL::Time - An SDL Perl extension for managing timers</p>

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<h1 id="CATEGORY">CATEGORY</h1><p><a href="#TOP" class="toplink">Top</a></p>
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<p>Core</p>

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<h1 id="SYNOPSIS">SYNOPSIS</h1><p><a href="#TOP" class="toplink">Top</a></p>
<div id="SYNOPSIS_CONTENT">
<pre> use warnings;
 use strict;

 use threads;
 use threads::shared;

 use SDL::Time;

 package foo;

 use SDL ':all';

 SDL::init(SDL_INIT_TIMER);

 my $tick :shared = 0;
 sub ticker { $tick++; warn $tick; return 100; }

 package main;

 my $id = SDL::Time::add_timer(100, 'foo::ticker');

 sleep(2);

 SDL::Time::remove_timer($id);

</pre>

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<h1 id="METHODS">METHODS</h1><p><a href="#TOP" class="toplink">Top</a></p>
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<h2 id="add_timer">add_timer</h2>
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<pre> my $id = SDL::Timer::add_timer( $ms_interval, $callback );

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<p>This runs in a separate thread and a cloned Perl thread.
<code>threads</code> and <code>threads::shared</code> must be used to share any variables the timer uses.</p>
<p>The <code>$callback</code> function, specified with a string of the function's name, will be called after the milliseconds of <code>$interval</code> have elapsed.
The actual delay may be longer than specified depending on the underlying OS.
The callback function is passed the current timer interval as well as the <code>$interval</code> parameter and should return the next timer interval.
If the return value from the callback is 0, the timer is cancelled; otherwise, the timer will continue to run.</p>
<p>The timer callback function may run in a different thread to your main program, so it shouldn't call any functions from within itself.
You may call SDL::push_event, however.</p>
<p><code>SDL::Time::add_timer</code> returns the identifier value of the generated timer or undef on error.</p>
<p><strong>Note:</strong> You must initialize (<code>SDL::init</code>) the timer subsystem to use this function.</p>

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<h2 id="remove_timer">remove_timer</h2>
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<pre> SDL::Timer::remove_timer( $id );

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<p>The other way to cancel a timer is to use <code>SDL::Time::remove_timer</code> on the <code>$id</code> of a timer.
This ID is the return value of the <code>SDL::Time::add_timer</code> function.</p>
<p><code>SDL::Time::remove_timer</code> returns <code>0</code> on success or <code>-1</code> on error.</p>

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