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Comparing AnyEvent/lib/AnyEvent.pm (file contents):
Revision 1.265 by root, Wed Jul 29 13:10:58 2009 UTC vs.
Revision 1.270 by root, Fri Jul 31 20:16:34 2009 UTC

181my variables are only visible after the statement in which they are 181my variables are only visible after the statement in which they are
182declared. 182declared.
183 183
184=head2 I/O WATCHERS 184=head2 I/O WATCHERS
185 185
186 $w = AnyEvent->io (
187 fh => <filehandle_or_fileno>,
188 poll => <"r" or "w">,
189 cb => <callback>,
190 );
191
186You can create an I/O watcher by calling the C<< AnyEvent->io >> method 192You can create an I/O watcher by calling the C<< AnyEvent->io >> method
187with the following mandatory key-value pairs as arguments: 193with the following mandatory key-value pairs as arguments:
188 194
189C<fh> is the Perl I<file handle> (or a naked file descriptor) to watch 195C<fh> is the Perl I<file handle> (or a naked file descriptor) to watch
190for events (AnyEvent might or might not keep a reference to this file 196for events (AnyEvent might or might not keep a reference to this file
219 undef $w; 225 undef $w;
220 }); 226 });
221 227
222=head2 TIME WATCHERS 228=head2 TIME WATCHERS
223 229
230 $w = AnyEvent->timer (after => <seconds>, cb => <callback>);
231
232 $w = AnyEvent->timer (
233 after => <fractional_seconds>,
234 interval => <fractional_seconds>,
235 cb => <callback>,
236 );
237
224You can create a time watcher by calling the C<< AnyEvent->timer >> 238You can create a time watcher by calling the C<< AnyEvent->timer >>
225method with the following mandatory arguments: 239method with the following mandatory arguments:
226 240
227C<after> specifies after how many seconds (fractional values are 241C<after> specifies after how many seconds (fractional values are
228supported) the callback should be invoked. C<cb> is the callback to invoke 242supported) the callback should be invoked. C<cb> is the callback to invoke
355 369
356=back 370=back
357 371
358=head2 SIGNAL WATCHERS 372=head2 SIGNAL WATCHERS
359 373
374 $w = AnyEvent->signal (signal => <uppercase_signal_name>, cb => <callback>);
375
360You can watch for signals using a signal watcher, C<signal> is the signal 376You can watch for signals using a signal watcher, C<signal> is the signal
361I<name> in uppercase and without any C<SIG> prefix, C<cb> is the Perl 377I<name> in uppercase and without any C<SIG> prefix, C<cb> is the Perl
362callback to be invoked whenever a signal occurs. 378callback to be invoked whenever a signal occurs.
363 379
364Although the callback might get passed parameters, their value and 380Although the callback might get passed parameters, their value and
383 my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 }); 399 my $w = AnyEvent->signal (signal => "INT", cb => sub { exit 1 });
384 400
385=head3 Signal Races, Delays and Workarounds 401=head3 Signal Races, Delays and Workarounds
386 402
387Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching 403Many event loops (e.g. Glib, Tk, Qt, IO::Async) do not support attaching
388callbacks to signals in a generic way, which is a pity, as you cannot do 404callbacks to signals in a generic way, which is a pity, as you cannot
389race-free signal handling in perl. AnyEvent will try to do it's best, but 405do race-free signal handling in perl, requiring C libraries for
406this. AnyEvent will try to do it's best, which means in some cases,
390in some cases, signals will be delayed. The maximum time a signal might 407signals will be delayed. The maximum time a signal might be delayed is
391be delayed is specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 408specified in C<$AnyEvent::MAX_SIGNAL_LATENCY> (default: 10 seconds). This
392seconds). This variable can be changed only before the first signal 409variable can be changed only before the first signal watcher is created,
393watcher is created, and should be left alone otherwise. Higher values 410and should be left alone otherwise. This variable determines how often
411AnyEvent polls for signals (in case a wake-up was missed). Higher values
394will cause fewer spurious wake-ups, which is better for power and CPU 412will cause fewer spurious wake-ups, which is better for power and CPU
413saving.
414
395saving. All these problems can be avoided by installing the optional 415All these problems can be avoided by installing the optional
396L<Async::Interrupt> module. This will not work with inherently broken 416L<Async::Interrupt> module, which works with most event loops. It will not
397event loops such as L<Event> or L<Event::Lib> (and not with L<POE> 417work with inherently broken event loops such as L<Event> or L<Event::Lib>
398currently, as POE does it's own workaround with one-second latency). With 418(and not with L<POE> currently, as POE does it's own workaround with
399those, you just have to suffer the delays. 419one-second latency). For those, you just have to suffer the delays.
400 420
401=head2 CHILD PROCESS WATCHERS 421=head2 CHILD PROCESS WATCHERS
422
423 $w = AnyEvent->child (pid => <process id>, cb => <callback>);
402 424
403You can also watch on a child process exit and catch its exit status. 425You can also watch on a child process exit and catch its exit status.
404 426
405The child process is specified by the C<pid> argument (one some backends, 427The child process is specified by the C<pid> argument (one some backends,
406using C<0> watches for any child process exit, on others this will 428using C<0> watches for any child process exit, on others this will
455 # do something else, then wait for process exit 477 # do something else, then wait for process exit
456 $done->recv; 478 $done->recv;
457 479
458=head2 IDLE WATCHERS 480=head2 IDLE WATCHERS
459 481
482 $w = AnyEvent->idle (cb => <callback>);
483
460Sometimes there is a need to do something, but it is not so important 484Sometimes there is a need to do something, but it is not so important
461to do it instantly, but only when there is nothing better to do. This 485to do it instantly, but only when there is nothing better to do. This
462"nothing better to do" is usually defined to be "no other events need 486"nothing better to do" is usually defined to be "no other events need
463attention by the event loop". 487attention by the event loop".
464 488
490 }); 514 });
491 }); 515 });
492 516
493=head2 CONDITION VARIABLES 517=head2 CONDITION VARIABLES
494 518
519 $cv = AnyEvent->condvar;
520
521 $cv->send (<list>);
522 my @res = $cv->recv;
523
495If you are familiar with some event loops you will know that all of them 524If you are familiar with some event loops you will know that all of them
496require you to run some blocking "loop", "run" or similar function that 525require you to run some blocking "loop", "run" or similar function that
497will actively watch for new events and call your callbacks. 526will actively watch for new events and call your callbacks.
498 527
499AnyEvent is slightly different: it expects somebody else to run the event 528AnyEvent is slightly different: it expects somebody else to run the event
761=item $cb = $cv->cb ($cb->($cv)) 790=item $cb = $cv->cb ($cb->($cv))
762 791
763This is a mutator function that returns the callback set and optionally 792This is a mutator function that returns the callback set and optionally
764replaces it before doing so. 793replaces it before doing so.
765 794
766The callback will be called when the condition becomes "true", i.e. when 795The callback will be called when the condition becomes (or already was)
767C<send> or C<croak> are called, with the only argument being the condition 796"true", i.e. when C<send> or C<croak> are called (or were called), with
768variable itself. Calling C<recv> inside the callback or at any later time 797the only argument being the condition variable itself. Calling C<recv>
769is guaranteed not to block. 798inside the callback or at any later time is guaranteed not to block.
770 799
771=back 800=back
772 801
773=head1 SUPPORTED EVENT LOOPS/BACKENDS 802=head1 SUPPORTED EVENT LOOPS/BACKENDS
774 803
1086 1115
1087BEGIN { AnyEvent::common_sense } 1116BEGIN { AnyEvent::common_sense }
1088 1117
1089use Carp (); 1118use Carp ();
1090 1119
1091our $VERSION = 4.881; 1120our $VERSION = 4.9;
1092our $MODEL; 1121our $MODEL;
1093 1122
1094our $AUTOLOAD; 1123our $AUTOLOAD;
1095our @ISA; 1124our @ISA;
1096 1125
1605 Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak}; 1634 Carp::croak $_[0]{_ae_croak} if $_[0]{_ae_croak};
1606 wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0] 1635 wantarray ? @{ $_[0]{_ae_sent} } : $_[0]{_ae_sent}[0]
1607} 1636}
1608 1637
1609sub cb { 1638sub cb {
1610 $_[0]{_ae_cb} = $_[1] if @_ > 1; 1639 my $cv = shift;
1640
1641 @_
1642 and $cv->{_ae_cb} = shift
1643 and $cv->{_ae_sent}
1644 and (delete $cv->{_ae_cb})->($cv);
1645
1611 $_[0]{_ae_cb} 1646 $cv->{_ae_cb}
1612} 1647}
1613 1648
1614sub begin { 1649sub begin {
1615 ++$_[0]{_ae_counter}; 1650 ++$_[0]{_ae_counter};
1616 $_[0]{_ae_end_cb} = $_[1] if @_ > 1; 1651 $_[0]{_ae_end_cb} = $_[1] if @_ > 1;
1622} 1657}
1623 1658
1624# undocumented/compatibility with pre-3.4 1659# undocumented/compatibility with pre-3.4
1625*broadcast = \&send; 1660*broadcast = \&send;
1626*wait = \&_wait; 1661*wait = \&_wait;
1662
1663#############################################################################
1664# "new" API, currently only emulation of it
1665#############################################################################
1666
1667package AE;
1668
1669sub io($$$) {
1670 AnyEvent->io (fh => $_[0], poll => $_[1] ? "w" : "r", cb => $_[2])
1671}
1672
1673sub timer($$$) {
1674 AnyEvent->timer (after => $_[0], interval => $_[1], cb => $_[2]);
1675}
1676
1677sub signal($$) {
1678 AnyEvent->signal (signal => $_[0], cb => $_[1]);
1679}
1680
1681sub child($$) {
1682 AnyEvent->child (pid => $_[0], cb => $_[1]);
1683}
1684
1685sub idle($) {
1686 AnyEvent->idle (cb => $_[0]);
1687}
1688
1689sub cv() {
1690 AnyEvent->condvar
1691}
1692
1693sub now() {
1694 AnyEvent->now
1695}
1696
1697sub now_update() {
1698 AnyEvent->now_update
1699}
1700
1701sub time() {
1702 AnyEvent->time
1703}
1627 1704
1628=head1 ERROR AND EXCEPTION HANDLING 1705=head1 ERROR AND EXCEPTION HANDLING
1629 1706
1630In general, AnyEvent does not do any error handling - it relies on the 1707In general, AnyEvent does not do any error handling - it relies on the
1631caller to do that if required. The L<AnyEvent::Strict> module (see also 1708caller to do that if required. The L<AnyEvent::Strict> module (see also

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