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=head1 NAME |
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AE - simpler/faster/newer/cooler AnyEvent API |
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=head1 SYNOPSIS |
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use AnyEvent; # not AE |
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=head1 DESCRIPTION |
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This module documents the new simpler AnyEvent API. |
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The rationale for the new API is that experience with L<EV> shows that |
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this API actually "works", despite it's lack of extensibility, leading to |
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a shorter, easier and faster API. |
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The main difference to AnyEvent is that instead of method calls, function |
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calls are used, and that no named arguments are used. |
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This makes calls to watcher creation functions really short, which can |
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make a program more readable, despite the lack of named parameters. |
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Function calls also allow more static type checking than method calls, so |
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many mistakes are caught at compiletime with this API. |
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Also, some backends (Perl and EV) are so fast that the method call |
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overhead is very noticable (with EV it increases the time five- to |
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six-fold, with Perl the method call overhead is about a factor of two). |
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At the moment, there will be no checking (L<AnyEvent::Strict> does not |
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affect his API), so the L<AnyEvent> API has a definite advantage here |
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still. |
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Note that the C<AE> API is an alternative to, not the future version of, |
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the AnyEvent API. Both APIs can be used interchangably and and there are |
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no plans to "switch", so if in doubt, use the L<AnyEvent> API. |
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As the AE API is complementary, not everything in the AnyEvent API is |
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available, so you still need to use AnyEvent for the finer stuff. Also, |
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you should not C<use AE> directly, C<use AnyEvent> will provide the AE |
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namespace. |
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=head2 FUNCTIONS |
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This section briefly describes the alternative watcher |
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constructors. Semantics and any methods are not described here, please |
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refer to the L<AnyEvent> manpage for the details. |
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=over 4 |
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=cut |
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package AE; |
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use AnyEvent (); # BEGIN { AnyEvent::common_sense } |
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=item $w = AE::io $fh_or_fd, $watch_write, $cb |
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Creates an I/O watcher that listens for read events (C<$watch_write> |
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false) or write events (C<$watch_write> is true) on the file handle or |
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file descriptor C<$fh_or_fd>. |
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The callback C<$cb> is invoked as soon and as long as I/O of the type |
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specified by C<$watch_write>) can be done on the file handle/descriptor. |
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Example: wait until STDIN becomes readable. |
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$stdin_ready = AE::io *STDIN, 0, sub { scalar <STDIN> }; |
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Example. wait until STDOUT becomes writable and print something. |
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$stdout_ready = AE::io *STDOUT, 1, sub { print STDOUT "woaw\n" }; |
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=item $w = AE::timer $after, $interval, $cb |
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Creates a timer watcher that invokes the callback C<$cb> after at least |
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C<$after> second have passed (C<$after> can be negative or C<0>). |
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If C<$interval> is C<0>, then the clalback will only be invoked once, |
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otherwise it must be a positive number of seconds that specified the |
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interval between successive invocations of the callback. |
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Example: print "too late" after at least one second has passed. |
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$timer_once = AE::timer 1, 0, sub { print "too late\n" }; |
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Example: print "blubb" once a second, starting as soon as possible. |
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$timer_repeated = AE::timer 0, 1, sub { print "blubb\n" }; |
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=item $w = AE::signal $signame, $cb |
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Invoke the callback c<$cb> each time one or more occurences of the named |
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signal C<$signame> are detected. |
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=item $w = AE::child $pid, $cb |
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Invokes the callbakc C<$cb> when the child with the given C<$pid> exits |
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(or all children, when C<$pid> is zero). |
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The callback will get the actual pid and exit status as arguments. |
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=item $w = AE::idle $cb |
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Invoke the callback C<$cb> each time the event loop is "idle" (has no |
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events outstanding), but do not prevent the event loop from polling for |
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more events. |
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=item $cv = AE::cv |
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=item $cv = AE::cv { BLOCK } |
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Create a new condition variable. The first form is identical to C<< |
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AnyEvent->condvar >>, the second form additionally sets the callback (as |
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if the C<cb> method is called on the condition variable). |
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=item AE::now |
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Returns the current event loop time (may be cached by the event loop). |
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=item AE::now_update |
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Ensures that the current event loop time is up to date. |
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=item AE::time |
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Return the current time (not cached, always consults a hardware clock). |
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=back |
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=head1 AUTHOR |
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Marc Lehmann <schmorp@schmorp.de> |
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http://home.schmorp.de/ |
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=cut |
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1 |
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