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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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# file handle or descriptor readable |
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my $w = AE::io $fh, 0, sub { ... }; |
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# one-shot or repeating timers |
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my $w = AE::timer $seconds, 0, sub { ... }; # once |
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my $w = AE::timer $seconds, $interval, sub { ... }; # repeated |
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print AE::now; # prints current event loop time |
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print AE::time; # think Time::HiRes::time or simply CORE::time. |
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|
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# POSIX signal |
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my $w = AE::signal TERM => sub { ... }; |
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|
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# child process exit |
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my $w = AE::child $pid, sub { |
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my ($pid, $status) = @_; |
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... |
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}; |
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|
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# called when event loop idle (if applicable) |
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my $w = AE::idle sub { ... }; |
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my $cv = AE::cv; # stores whether a condition was flagged |
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$cv->send; # wake up current and all future recv's |
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$cv->recv; # enters "main loop" till $condvar gets ->send |
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# use a condvar in callback mode: |
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$cv->cb (sub { $_[0]->recv }); |
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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 its lack of extensibility, leading to |
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a shorter, easier and faster API. |
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The main differences from AnyEvent is that function calls are used |
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instead of method calls, 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 compile-time 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 noticeable (with EV it increases the execution time five- |
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to six-fold, with Perl the method call overhead is about a factor of two). |
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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 interchangeably and there are |
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no plans to "switch", so if in doubt, feel free to use the L<AnyEvent> |
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API in new code. |
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As the AE API is complementary, not everything in the AnyEvent API is |
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available, and 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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|
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At the moment, these functions will become slower then their method-call |
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counterparts when using L<AnyEvent::Strict> or L<AnyEvent::Debug>::wrap. |
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|
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=head2 FUNCTIONS |
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This section briefly describes the alternative watcher constructors and |
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other functions available inside the C<AE> namespace. Semantics are not |
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described here; please refer to the description of the function or method |
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with the same name in the L<AnyEvent> manpage for the details. |
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|
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=over 4 |
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=cut |
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|
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package AE; |
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|
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use AnyEvent (); # BEGIN { AnyEvent::common_sense } |
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our $VERSION = $AnyEvent::VERSION; |
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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<$interval> is C<0>, then the callback will only be invoked once, |
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otherwise it must be a positive number of seconds that specifies the |
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interval between successive invocations of the callback. |
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Example: print "too late" after at least one second has passed. |
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$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 occurrences of the |
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named signal C<$signame> are detected. |
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=item $w = AE::child $pid, $cb |
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Invokes the callback C<$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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=item AE::postpone { BLOCK } |
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Exactly the same as C<AnyEvent:::postpone>. |
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=item AE::log $level, $msg[, @args] |
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Exactly the same as C<AnyEvent::log> (or C<AnyEvent::Log::log>). |
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=back |
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=head1 AUTHOR |
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|
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Marc Lehmann <schmorp@schmorp.de> |
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http://anyevent.schmorp.de |
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=cut |
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1 |
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