1 | =head1 NAME |
1 | =head1 NAME |
2 | |
2 | |
3 | AnyEvent - provide framework for multiple event loops |
3 | AnyEvent - provide framework for multiple event loops |
4 | |
4 | |
5 | EV, Event, Glib, Tk, Perl, Event::Lib, Qt, POE - various supported event loops |
5 | EV, Event, Glib, Tk, Perl, Event::Lib, Qt and POE are various supported |
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6 | event loops. |
6 | |
7 | |
7 | =head1 SYNOPSIS |
8 | =head1 SYNOPSIS |
8 | |
9 | |
9 | use AnyEvent; |
10 | use AnyEvent; |
10 | |
11 | |
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12 | # file descriptor readable |
11 | my $w = AnyEvent->io (fh => $fh, poll => "r|w", cb => sub { ... }); |
13 | my $w = AnyEvent->io (fh => $fh, poll => "r", cb => sub { ... }); |
12 | |
14 | |
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15 | # one-shot or repeating timers |
13 | my $w = AnyEvent->timer (after => $seconds, cb => sub { ... }); |
16 | my $w = AnyEvent->timer (after => $seconds, cb => sub { ... }); |
14 | my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ... |
17 | my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ... |
15 | |
18 | |
16 | print AnyEvent->now; # prints current event loop time |
19 | print AnyEvent->now; # prints current event loop time |
17 | print AnyEvent->time; # think Time::HiRes::time or simply CORE::time. |
20 | print AnyEvent->time; # think Time::HiRes::time or simply CORE::time. |
18 | |
21 | |
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22 | # POSIX signal |
19 | my $w = AnyEvent->signal (signal => "TERM", cb => sub { ... }); |
23 | my $w = AnyEvent->signal (signal => "TERM", cb => sub { ... }); |
20 | |
24 | |
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25 | # child process exit |
21 | my $w = AnyEvent->child (pid => $pid, cb => sub { |
26 | my $w = AnyEvent->child (pid => $pid, cb => sub { |
22 | my ($pid, $status) = @_; |
27 | my ($pid, $status) = @_; |
23 | ... |
28 | ... |
24 | }); |
29 | }); |
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30 | |
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31 | # called when event loop idle (if applicable) |
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32 | my $w = AnyEvent->idle (cb => sub { ... }); |
25 | |
33 | |
26 | my $w = AnyEvent->condvar; # stores whether a condition was flagged |
34 | my $w = AnyEvent->condvar; # stores whether a condition was flagged |
27 | $w->send; # wake up current and all future recv's |
35 | $w->send; # wake up current and all future recv's |
28 | $w->recv; # enters "main loop" till $condvar gets ->send |
36 | $w->recv; # enters "main loop" till $condvar gets ->send |
29 | # use a condvar in callback mode: |
37 | # use a condvar in callback mode: |
… | |
… | |
137 | These watchers are normal Perl objects with normal Perl lifetime. After |
145 | These watchers are normal Perl objects with normal Perl lifetime. After |
138 | creating a watcher it will immediately "watch" for events and invoke the |
146 | creating a watcher it will immediately "watch" for events and invoke the |
139 | callback when the event occurs (of course, only when the event model |
147 | callback when the event occurs (of course, only when the event model |
140 | is in control). |
148 | is in control). |
141 | |
149 | |
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150 | Note that B<callbacks must not permanently change global variables> |
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151 | potentially in use by the event loop (such as C<$_> or C<$[>) and that B<< |
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152 | callbacks must not C<die> >>. The former is good programming practise in |
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153 | Perl and the latter stems from the fact that exception handling differs |
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154 | widely between event loops. |
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155 | |
142 | To disable the watcher you have to destroy it (e.g. by setting the |
156 | To disable the watcher you have to destroy it (e.g. by setting the |
143 | variable you store it in to C<undef> or otherwise deleting all references |
157 | variable you store it in to C<undef> or otherwise deleting all references |
144 | to it). |
158 | to it). |
145 | |
159 | |
146 | All watchers are created by calling a method on the C<AnyEvent> class. |
160 | All watchers are created by calling a method on the C<AnyEvent> class. |
… | |
… | |
162 | =head2 I/O WATCHERS |
176 | =head2 I/O WATCHERS |
163 | |
177 | |
164 | You can create an I/O watcher by calling the C<< AnyEvent->io >> method |
178 | You can create an I/O watcher by calling the C<< AnyEvent->io >> method |
165 | with the following mandatory key-value pairs as arguments: |
179 | with the following mandatory key-value pairs as arguments: |
166 | |
180 | |
167 | C<fh> the Perl I<file handle> (I<not> file descriptor) to watch for events |
181 | C<fh> is the Perl I<file handle> (I<not> file descriptor) to watch |
168 | (AnyEvent might or might not keep a reference to this file handle). C<poll> |
182 | for events (AnyEvent might or might not keep a reference to this file |
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183 | handle). Note that only file handles pointing to things for which |
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184 | non-blocking operation makes sense are allowed. This includes sockets, |
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185 | most character devices, pipes, fifos and so on, but not for example files |
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186 | or block devices. |
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187 | |
169 | must be a string that is either C<r> or C<w>, which creates a watcher |
188 | C<poll> must be a string that is either C<r> or C<w>, which creates a |
170 | waiting for "r"eadable or "w"ritable events, respectively. C<cb> is the |
189 | watcher waiting for "r"eadable or "w"ritable events, respectively. |
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190 | |
171 | callback to invoke each time the file handle becomes ready. |
191 | C<cb> is the callback to invoke each time the file handle becomes ready. |
172 | |
192 | |
173 | Although the callback might get passed parameters, their value and |
193 | Although the callback might get passed parameters, their value and |
174 | presence is undefined and you cannot rely on them. Portable AnyEvent |
194 | presence is undefined and you cannot rely on them. Portable AnyEvent |
175 | callbacks cannot use arguments passed to I/O watcher callbacks. |
195 | callbacks cannot use arguments passed to I/O watcher callbacks. |
176 | |
196 | |
… | |
… | |
308 | In either case, if you care (and in most cases, you don't), then you |
328 | In either case, if you care (and in most cases, you don't), then you |
309 | can get whatever behaviour you want with any event loop, by taking the |
329 | can get whatever behaviour you want with any event loop, by taking the |
310 | difference between C<< AnyEvent->time >> and C<< AnyEvent->now >> into |
330 | difference between C<< AnyEvent->time >> and C<< AnyEvent->now >> into |
311 | account. |
331 | account. |
312 | |
332 | |
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333 | =item AnyEvent->now_update |
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334 | |
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335 | Some event loops (such as L<EV> or L<AnyEvent::Impl::Perl>) cache |
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336 | the current time for each loop iteration (see the discussion of L<< |
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337 | AnyEvent->now >>, above). |
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338 | |
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339 | When a callback runs for a long time (or when the process sleeps), then |
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340 | this "current" time will differ substantially from the real time, which |
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341 | might affect timers and time-outs. |
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342 | |
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343 | When this is the case, you can call this method, which will update the |
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344 | event loop's idea of "current time". |
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345 | |
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346 | Note that updating the time I<might> cause some events to be handled. |
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347 | |
313 | =back |
348 | =back |
314 | |
349 | |
315 | =head2 SIGNAL WATCHERS |
350 | =head2 SIGNAL WATCHERS |
316 | |
351 | |
317 | You can watch for signals using a signal watcher, C<signal> is the signal |
352 | You can watch for signals using a signal watcher, C<signal> is the signal |
… | |
… | |
357 | |
392 | |
358 | There is a slight catch to child watchers, however: you usually start them |
393 | There is a slight catch to child watchers, however: you usually start them |
359 | I<after> the child process was created, and this means the process could |
394 | I<after> the child process was created, and this means the process could |
360 | have exited already (and no SIGCHLD will be sent anymore). |
395 | have exited already (and no SIGCHLD will be sent anymore). |
361 | |
396 | |
362 | Not all event models handle this correctly (POE doesn't), but even for |
397 | Not all event models handle this correctly (neither POE nor IO::Async do, |
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398 | see their AnyEvent::Impl manpages for details), but even for event models |
363 | event models that I<do> handle this correctly, they usually need to be |
399 | that I<do> handle this correctly, they usually need to be loaded before |
364 | loaded before the process exits (i.e. before you fork in the first place). |
400 | the process exits (i.e. before you fork in the first place). AnyEvent's |
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401 | pure perl event loop handles all cases correctly regardless of when you |
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402 | start the watcher. |
365 | |
403 | |
366 | This means you cannot create a child watcher as the very first thing in an |
404 | This means you cannot create a child watcher as the very first |
367 | AnyEvent program, you I<have> to create at least one watcher before you |
405 | thing in an AnyEvent program, you I<have> to create at least one |
368 | C<fork> the child (alternatively, you can call C<AnyEvent::detect>). |
406 | watcher before you C<fork> the child (alternatively, you can call |
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407 | C<AnyEvent::detect>). |
369 | |
408 | |
370 | Example: fork a process and wait for it |
409 | Example: fork a process and wait for it |
371 | |
410 | |
372 | my $done = AnyEvent->condvar; |
411 | my $done = AnyEvent->condvar; |
373 | |
412 | |
… | |
… | |
383 | ); |
422 | ); |
384 | |
423 | |
385 | # do something else, then wait for process exit |
424 | # do something else, then wait for process exit |
386 | $done->recv; |
425 | $done->recv; |
387 | |
426 | |
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427 | =head2 IDLE WATCHERS |
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428 | |
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429 | Sometimes there is a need to do something, but it is not so important |
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430 | to do it instantly, but only when there is nothing better to do. This |
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431 | "nothing better to do" is usually defined to be "no other events need |
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432 | attention by the event loop". |
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433 | |
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434 | Idle watchers ideally get invoked when the event loop has nothing |
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435 | better to do, just before it would block the process to wait for new |
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436 | events. Instead of blocking, the idle watcher is invoked. |
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437 | |
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438 | Most event loops unfortunately do not really support idle watchers (only |
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439 | EV, Event and Glib do it in a usable fashion) - for the rest, AnyEvent |
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440 | will simply call the callback "from time to time". |
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441 | |
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442 | Example: read lines from STDIN, but only process them when the |
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443 | program is otherwise idle: |
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444 | |
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445 | my @lines; # read data |
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446 | my $idle_w; |
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447 | my $io_w = AnyEvent->io (fh => \*STDIN, poll => 'r', cb => sub { |
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448 | push @lines, scalar <STDIN>; |
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449 | |
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450 | # start an idle watcher, if not already done |
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451 | $idle_w ||= AnyEvent->idle (cb => sub { |
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452 | # handle only one line, when there are lines left |
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453 | if (my $line = shift @lines) { |
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454 | print "handled when idle: $line"; |
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455 | } else { |
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456 | # otherwise disable the idle watcher again |
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457 | undef $idle_w; |
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458 | } |
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459 | }); |
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460 | }); |
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461 | |
388 | =head2 CONDITION VARIABLES |
462 | =head2 CONDITION VARIABLES |
389 | |
463 | |
390 | If you are familiar with some event loops you will know that all of them |
464 | If you are familiar with some event loops you will know that all of them |
391 | require you to run some blocking "loop", "run" or similar function that |
465 | require you to run some blocking "loop", "run" or similar function that |
392 | will actively watch for new events and call your callbacks. |
466 | will actively watch for new events and call your callbacks. |
… | |
… | |
660 | AnyEvent::Impl::Tk based on Tk, very bad choice. |
734 | AnyEvent::Impl::Tk based on Tk, very bad choice. |
661 | AnyEvent::Impl::Qt based on Qt, cannot be autoprobed (see its docs). |
735 | AnyEvent::Impl::Qt based on Qt, cannot be autoprobed (see its docs). |
662 | AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. |
736 | AnyEvent::Impl::EventLib based on Event::Lib, leaks memory and worse. |
663 | AnyEvent::Impl::POE based on POE, not generic enough for full support. |
737 | AnyEvent::Impl::POE based on POE, not generic enough for full support. |
664 | |
738 | |
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739 | # warning, support for IO::Async is only partial, as it is too broken |
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740 | # and limited toe ven support the AnyEvent API. See AnyEvent::Impl::Async. |
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741 | AnyEvent::Impl::IOAsync based on IO::Async, cannot be autoprobed (see its docs). |
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742 | |
665 | There is no support for WxWidgets, as WxWidgets has no support for |
743 | There is no support for WxWidgets, as WxWidgets has no support for |
666 | watching file handles. However, you can use WxWidgets through the |
744 | watching file handles. However, you can use WxWidgets through the |
667 | POE Adaptor, as POE has a Wx backend that simply polls 20 times per |
745 | POE Adaptor, as POE has a Wx backend that simply polls 20 times per |
668 | second, which was considered to be too horrible to even consider for |
746 | second, which was considered to be too horrible to even consider for |
669 | AnyEvent. Likewise, other POE backends can be used by AnyEvent by using |
747 | AnyEvent. Likewise, other POE backends can be used by AnyEvent by using |
… | |
… | |
861 | no warnings; |
939 | no warnings; |
862 | use strict qw(vars subs); |
940 | use strict qw(vars subs); |
863 | |
941 | |
864 | use Carp; |
942 | use Carp; |
865 | |
943 | |
866 | our $VERSION = 4.34; |
944 | our $VERSION = 4.412; |
867 | our $MODEL; |
945 | our $MODEL; |
868 | |
946 | |
869 | our $AUTOLOAD; |
947 | our $AUTOLOAD; |
870 | our @ISA; |
948 | our @ISA; |
871 | |
949 | |
872 | our @REGISTRY; |
950 | our @REGISTRY; |
873 | |
951 | |
874 | our $WIN32; |
952 | our $WIN32; |
875 | |
953 | |
876 | BEGIN { |
954 | BEGIN { |
877 | my $win32 = ! ! ($^O =~ /mswin32/i); |
955 | eval "sub WIN32(){ " . (($^O =~ /mswin32/i)*1) ." }"; |
878 | eval "sub WIN32(){ $win32 }"; |
956 | eval "sub TAINT(){ " . (${^TAINT}*1) . " }"; |
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957 | |
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958 | delete @ENV{grep /^PERL_ANYEVENT_/, keys %ENV} |
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959 | if ${^TAINT}; |
879 | } |
960 | } |
880 | |
961 | |
881 | our $verbose = $ENV{PERL_ANYEVENT_VERBOSE}*1; |
962 | our $verbose = $ENV{PERL_ANYEVENT_VERBOSE}*1; |
882 | |
963 | |
883 | our %PROTOCOL; # (ipv4|ipv6) => (1|2), higher numbers are preferred |
964 | our %PROTOCOL; # (ipv4|ipv6) => (1|2), higher numbers are preferred |
… | |
… | |
901 | [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy |
982 | [Event::Lib:: => AnyEvent::Impl::EventLib::], # too buggy |
902 | [Qt:: => AnyEvent::Impl::Qt::], # requires special main program |
983 | [Qt:: => AnyEvent::Impl::Qt::], # requires special main program |
903 | [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza |
984 | [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza |
904 | [Wx:: => AnyEvent::Impl::POE::], |
985 | [Wx:: => AnyEvent::Impl::POE::], |
905 | [Prima:: => AnyEvent::Impl::POE::], |
986 | [Prima:: => AnyEvent::Impl::POE::], |
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987 | # IO::Async is just too broken - we would need workaorunds for its |
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988 | # byzantine signal and broken child handling, among others. |
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989 | # IO::Async is rather hard to detect, as it doesn't have any |
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990 | # obvious default class. |
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991 | # [IO::Async:: => AnyEvent::Impl::IOAsync::], # requires special main program |
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992 | # [IO::Async::Loop:: => AnyEvent::Impl::IOAsync::], # requires special main program |
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993 | # [IO::Async::Notifier:: => AnyEvent::Impl::IOAsync::], # requires special main program |
906 | ); |
994 | ); |
907 | |
995 | |
908 | our %method = map +($_ => 1), qw(io timer time now signal child condvar one_event DESTROY); |
996 | our %method = map +($_ => 1), |
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997 | qw(io timer time now now_update signal child idle condvar one_event DESTROY); |
909 | |
998 | |
910 | our @post_detect; |
999 | our @post_detect; |
911 | |
1000 | |
912 | sub post_detect(&) { |
1001 | sub post_detect(&) { |
913 | my ($cb) = @_; |
1002 | my ($cb) = @_; |
… | |
… | |
918 | 1 |
1007 | 1 |
919 | } else { |
1008 | } else { |
920 | push @post_detect, $cb; |
1009 | push @post_detect, $cb; |
921 | |
1010 | |
922 | defined wantarray |
1011 | defined wantarray |
923 | ? bless \$cb, "AnyEvent::Util::PostDetect" |
1012 | ? bless \$cb, "AnyEvent::Util::postdetect" |
924 | : () |
1013 | : () |
925 | } |
1014 | } |
926 | } |
1015 | } |
927 | |
1016 | |
928 | sub AnyEvent::Util::PostDetect::DESTROY { |
1017 | sub AnyEvent::Util::postdetect::DESTROY { |
929 | @post_detect = grep $_ != ${$_[0]}, @post_detect; |
1018 | @post_detect = grep $_ != ${$_[0]}, @post_detect; |
930 | } |
1019 | } |
931 | |
1020 | |
932 | sub detect() { |
1021 | sub detect() { |
933 | unless ($MODEL) { |
1022 | unless ($MODEL) { |
… | |
… | |
970 | last; |
1059 | last; |
971 | } |
1060 | } |
972 | } |
1061 | } |
973 | |
1062 | |
974 | $MODEL |
1063 | $MODEL |
975 | or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib."; |
1064 | or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.\n"; |
976 | } |
1065 | } |
977 | } |
1066 | } |
978 | |
1067 | |
979 | push @{"$MODEL\::ISA"}, "AnyEvent::Base"; |
1068 | push @{"$MODEL\::ISA"}, "AnyEvent::Base"; |
980 | |
1069 | |
… | |
… | |
1001 | } |
1090 | } |
1002 | |
1091 | |
1003 | # utility function to dup a filehandle. this is used by many backends |
1092 | # utility function to dup a filehandle. this is used by many backends |
1004 | # to support binding more than one watcher per filehandle (they usually |
1093 | # to support binding more than one watcher per filehandle (they usually |
1005 | # allow only one watcher per fd, so we dup it to get a different one). |
1094 | # allow only one watcher per fd, so we dup it to get a different one). |
1006 | sub _dupfh($$$$) { |
1095 | sub _dupfh($$;$$) { |
1007 | my ($poll, $fh, $r, $w) = @_; |
1096 | my ($poll, $fh, $r, $w) = @_; |
1008 | |
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1009 | require Fcntl; |
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1010 | |
1097 | |
1011 | # cygwin requires the fh mode to be matching, unix doesn't |
1098 | # cygwin requires the fh mode to be matching, unix doesn't |
1012 | my ($rw, $mode) = $poll eq "r" ? ($r, "<") |
1099 | my ($rw, $mode) = $poll eq "r" ? ($r, "<") |
1013 | : $poll eq "w" ? ($w, ">") |
1100 | : $poll eq "w" ? ($w, ">") |
1014 | : Carp::croak "AnyEvent->io requires poll set to either 'r' or 'w'"; |
1101 | : Carp::croak "AnyEvent->io requires poll set to either 'r' or 'w'"; |
1015 | |
1102 | |
1016 | open my $fh2, "$mode&" . fileno $fh |
1103 | open my $fh2, "$mode&" . fileno $fh |
1017 | or die "cannot dup() filehandle: $!"; |
1104 | or die "cannot dup() filehandle: $!,"; |
1018 | |
1105 | |
1019 | # we assume CLOEXEC is already set by perl in all important cases |
1106 | # we assume CLOEXEC is already set by perl in all important cases |
1020 | |
1107 | |
1021 | ($fh2, $rw) |
1108 | ($fh2, $rw) |
1022 | } |
1109 | } |
1023 | |
1110 | |
1024 | package AnyEvent::Base; |
1111 | package AnyEvent::Base; |
1025 | |
1112 | |
1026 | # default implementation for now and time |
1113 | # default implementations for many methods |
1027 | |
1114 | |
1028 | BEGIN { |
1115 | BEGIN { |
1029 | if (eval "use Time::HiRes (); time (); 1") { |
1116 | if (eval "use Time::HiRes (); Time::HiRes::time (); 1") { |
1030 | *_time = \&Time::HiRes::time; |
1117 | *_time = \&Time::HiRes::time; |
1031 | # if (eval "use POSIX (); (POSIX::times())... |
1118 | # if (eval "use POSIX (); (POSIX::times())... |
1032 | } else { |
1119 | } else { |
1033 | *_time = sub { time }; # epic fail |
1120 | *_time = sub { time }; # epic fail |
1034 | } |
1121 | } |
1035 | } |
1122 | } |
1036 | |
1123 | |
1037 | sub time { _time } |
1124 | sub time { _time } |
1038 | sub now { _time } |
1125 | sub now { _time } |
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1126 | sub now_update { } |
1039 | |
1127 | |
1040 | # default implementation for ->condvar |
1128 | # default implementation for ->condvar |
1041 | |
1129 | |
1042 | sub condvar { |
1130 | sub condvar { |
1043 | bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, AnyEvent::CondVar:: |
1131 | bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar" |
1044 | } |
1132 | } |
1045 | |
1133 | |
1046 | # default implementation for ->signal |
1134 | # default implementation for ->signal |
1047 | |
1135 | |
1048 | our %SIG_CB; |
1136 | our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO); |
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1137 | |
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1138 | sub _signal_exec { |
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1139 | sysread $SIGPIPE_R, my $dummy, 4; |
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1140 | |
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1141 | while (%SIG_EV) { |
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1142 | for (keys %SIG_EV) { |
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1143 | delete $SIG_EV{$_}; |
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1144 | $_->() for values %{ $SIG_CB{$_} || {} }; |
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1145 | } |
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1146 | } |
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1147 | } |
1049 | |
1148 | |
1050 | sub signal { |
1149 | sub signal { |
1051 | my (undef, %arg) = @_; |
1150 | my (undef, %arg) = @_; |
1052 | |
1151 | |
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1152 | unless ($SIGPIPE_R) { |
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1153 | require Fcntl; |
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1154 | |
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1155 | if (AnyEvent::WIN32) { |
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1156 | require AnyEvent::Util; |
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1157 | |
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1158 | ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe (); |
|
|
1159 | AnyEvent::Util::fh_nonblocking ($SIGPIPE_R) if $SIGPIPE_R; |
|
|
1160 | AnyEvent::Util::fh_nonblocking ($SIGPIPE_W) if $SIGPIPE_W; # just in case |
|
|
1161 | } else { |
|
|
1162 | pipe $SIGPIPE_R, $SIGPIPE_W; |
|
|
1163 | fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R; |
|
|
1164 | fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case |
|
|
1165 | |
|
|
1166 | # not strictly required, as $^F is normally 2, but let's make sure... |
|
|
1167 | fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; |
|
|
1168 | fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; |
|
|
1169 | } |
|
|
1170 | |
|
|
1171 | $SIGPIPE_R |
|
|
1172 | or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n"; |
|
|
1173 | |
|
|
1174 | $SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec); |
|
|
1175 | } |
|
|
1176 | |
1053 | my $signal = uc $arg{signal} |
1177 | my $signal = uc $arg{signal} |
1054 | or Carp::croak "required option 'signal' is missing"; |
1178 | or Carp::croak "required option 'signal' is missing"; |
1055 | |
1179 | |
1056 | $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; |
1180 | $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; |
1057 | $SIG{$signal} ||= sub { |
1181 | $SIG{$signal} ||= sub { |
1058 | $_->() for values %{ $SIG_CB{$signal} || {} }; |
1182 | local $!; |
|
|
1183 | syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV; |
|
|
1184 | undef $SIG_EV{$signal}; |
1059 | }; |
1185 | }; |
1060 | |
1186 | |
1061 | bless [$signal, $arg{cb}], "AnyEvent::Base::Signal" |
1187 | bless [$signal, $arg{cb}], "AnyEvent::Base::signal" |
1062 | } |
1188 | } |
1063 | |
1189 | |
1064 | sub AnyEvent::Base::Signal::DESTROY { |
1190 | sub AnyEvent::Base::signal::DESTROY { |
1065 | my ($signal, $cb) = @{$_[0]}; |
1191 | my ($signal, $cb) = @{$_[0]}; |
1066 | |
1192 | |
1067 | delete $SIG_CB{$signal}{$cb}; |
1193 | delete $SIG_CB{$signal}{$cb}; |
1068 | |
1194 | |
|
|
1195 | # delete doesn't work with older perls - they then |
|
|
1196 | # print weird messages, or just unconditionally exit |
|
|
1197 | # instead of getting the default action. |
1069 | delete $SIG{$signal} unless keys %{ $SIG_CB{$signal} }; |
1198 | undef $SIG{$signal} unless keys %{ $SIG_CB{$signal} }; |
1070 | } |
1199 | } |
1071 | |
1200 | |
1072 | # default implementation for ->child |
1201 | # default implementation for ->child |
1073 | |
1202 | |
1074 | our %PID_CB; |
1203 | our %PID_CB; |
1075 | our $CHLD_W; |
1204 | our $CHLD_W; |
1076 | our $CHLD_DELAY_W; |
1205 | our $CHLD_DELAY_W; |
1077 | our $PID_IDLE; |
|
|
1078 | our $WNOHANG; |
1206 | our $WNOHANG; |
1079 | |
1207 | |
1080 | sub _child_wait { |
1208 | sub _sigchld { |
1081 | while (0 < (my $pid = waitpid -1, $WNOHANG)) { |
1209 | while (0 < (my $pid = waitpid -1, $WNOHANG)) { |
1082 | $_->($pid, $?) for (values %{ $PID_CB{$pid} || {} }), |
1210 | $_->($pid, $?) for (values %{ $PID_CB{$pid} || {} }), |
1083 | (values %{ $PID_CB{0} || {} }); |
1211 | (values %{ $PID_CB{0} || {} }); |
1084 | } |
1212 | } |
1085 | |
|
|
1086 | undef $PID_IDLE; |
|
|
1087 | } |
|
|
1088 | |
|
|
1089 | sub _sigchld { |
|
|
1090 | # make sure we deliver these changes "synchronous" with the event loop. |
|
|
1091 | $CHLD_DELAY_W ||= AnyEvent->timer (after => 0, cb => sub { |
|
|
1092 | undef $CHLD_DELAY_W; |
|
|
1093 | &_child_wait; |
|
|
1094 | }); |
|
|
1095 | } |
1213 | } |
1096 | |
1214 | |
1097 | sub child { |
1215 | sub child { |
1098 | my (undef, %arg) = @_; |
1216 | my (undef, %arg) = @_; |
1099 | |
1217 | |
1100 | defined (my $pid = $arg{pid} + 0) |
1218 | defined (my $pid = $arg{pid} + 0) |
1101 | or Carp::croak "required option 'pid' is missing"; |
1219 | or Carp::croak "required option 'pid' is missing"; |
1102 | |
1220 | |
1103 | $PID_CB{$pid}{$arg{cb}} = $arg{cb}; |
1221 | $PID_CB{$pid}{$arg{cb}} = $arg{cb}; |
1104 | |
1222 | |
1105 | unless ($WNOHANG) { |
|
|
1106 | $WNOHANG = eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1; |
1223 | $WNOHANG ||= eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1; |
1107 | } |
|
|
1108 | |
1224 | |
1109 | unless ($CHLD_W) { |
1225 | unless ($CHLD_W) { |
1110 | $CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld); |
1226 | $CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld); |
1111 | # child could be a zombie already, so make at least one round |
1227 | # child could be a zombie already, so make at least one round |
1112 | &_sigchld; |
1228 | &_sigchld; |
1113 | } |
1229 | } |
1114 | |
1230 | |
1115 | bless [$pid, $arg{cb}], "AnyEvent::Base::Child" |
1231 | bless [$pid, $arg{cb}], "AnyEvent::Base::child" |
1116 | } |
1232 | } |
1117 | |
1233 | |
1118 | sub AnyEvent::Base::Child::DESTROY { |
1234 | sub AnyEvent::Base::child::DESTROY { |
1119 | my ($pid, $cb) = @{$_[0]}; |
1235 | my ($pid, $cb) = @{$_[0]}; |
1120 | |
1236 | |
1121 | delete $PID_CB{$pid}{$cb}; |
1237 | delete $PID_CB{$pid}{$cb}; |
1122 | delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} }; |
1238 | delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} }; |
1123 | |
1239 | |
1124 | undef $CHLD_W unless keys %PID_CB; |
1240 | undef $CHLD_W unless keys %PID_CB; |
|
|
1241 | } |
|
|
1242 | |
|
|
1243 | # idle emulation is done by simply using a timer, regardless |
|
|
1244 | # of whether the process is idle or not, and not letting |
|
|
1245 | # the callback use more than 50% of the time. |
|
|
1246 | sub idle { |
|
|
1247 | my (undef, %arg) = @_; |
|
|
1248 | |
|
|
1249 | my ($cb, $w, $rcb) = $arg{cb}; |
|
|
1250 | |
|
|
1251 | $rcb = sub { |
|
|
1252 | if ($cb) { |
|
|
1253 | $w = _time; |
|
|
1254 | &$cb; |
|
|
1255 | $w = _time - $w; |
|
|
1256 | |
|
|
1257 | # never use more then 50% of the time for the idle watcher, |
|
|
1258 | # within some limits |
|
|
1259 | $w = 0.0001 if $w < 0.0001; |
|
|
1260 | $w = 5 if $w > 5; |
|
|
1261 | |
|
|
1262 | $w = AnyEvent->timer (after => $w, cb => $rcb); |
|
|
1263 | } else { |
|
|
1264 | # clean up... |
|
|
1265 | undef $w; |
|
|
1266 | undef $rcb; |
|
|
1267 | } |
|
|
1268 | }; |
|
|
1269 | |
|
|
1270 | $w = AnyEvent->timer (after => 0.05, cb => $rcb); |
|
|
1271 | |
|
|
1272 | bless \\$cb, "AnyEvent::Base::idle" |
|
|
1273 | } |
|
|
1274 | |
|
|
1275 | sub AnyEvent::Base::idle::DESTROY { |
|
|
1276 | undef $${$_[0]}; |
1125 | } |
1277 | } |
1126 | |
1278 | |
1127 | package AnyEvent::CondVar; |
1279 | package AnyEvent::CondVar; |
1128 | |
1280 | |
1129 | our @ISA = AnyEvent::CondVar::Base::; |
1281 | our @ISA = AnyEvent::CondVar::Base::; |
… | |
… | |
1203 | so on. |
1355 | so on. |
1204 | |
1356 | |
1205 | =head1 ENVIRONMENT VARIABLES |
1357 | =head1 ENVIRONMENT VARIABLES |
1206 | |
1358 | |
1207 | The following environment variables are used by this module or its |
1359 | The following environment variables are used by this module or its |
1208 | submodules: |
1360 | submodules. |
|
|
1361 | |
|
|
1362 | Note that AnyEvent will remove I<all> environment variables starting with |
|
|
1363 | C<PERL_ANYEVENT_> from C<%ENV> when it is loaded while taint mode is |
|
|
1364 | enabled. |
1209 | |
1365 | |
1210 | =over 4 |
1366 | =over 4 |
1211 | |
1367 | |
1212 | =item C<PERL_ANYEVENT_VERBOSE> |
1368 | =item C<PERL_ANYEVENT_VERBOSE> |
1213 | |
1369 | |
… | |
… | |
1225 | =item C<PERL_ANYEVENT_STRICT> |
1381 | =item C<PERL_ANYEVENT_STRICT> |
1226 | |
1382 | |
1227 | AnyEvent does not do much argument checking by default, as thorough |
1383 | AnyEvent does not do much argument checking by default, as thorough |
1228 | argument checking is very costly. Setting this variable to a true value |
1384 | argument checking is very costly. Setting this variable to a true value |
1229 | will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly |
1385 | will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly |
1230 | check the arguments passed to most method calls. If it finds any problems |
1386 | check the arguments passed to most method calls. If it finds any problems, |
1231 | it will croak. |
1387 | it will croak. |
1232 | |
1388 | |
1233 | In other words, enables "strict" mode. |
1389 | In other words, enables "strict" mode. |
1234 | |
1390 | |
1235 | Unlike C<use strict>, it is definitely recommended ot keep it off in |
1391 | Unlike C<use strict>, it is definitely recommended to keep it off in |
1236 | production. Keeping C<PERL_ANYEVENT_STRICT=1> in your environment while |
1392 | production. Keeping C<PERL_ANYEVENT_STRICT=1> in your environment while |
1237 | developing programs can be very useful, however. |
1393 | developing programs can be very useful, however. |
1238 | |
1394 | |
1239 | =item C<PERL_ANYEVENT_MODEL> |
1395 | =item C<PERL_ANYEVENT_MODEL> |
1240 | |
1396 | |
… | |
… | |
1753 | =item * C-based event loops perform very well with small number of |
1909 | =item * C-based event loops perform very well with small number of |
1754 | watchers, as the management overhead dominates. |
1910 | watchers, as the management overhead dominates. |
1755 | |
1911 | |
1756 | =back |
1912 | =back |
1757 | |
1913 | |
|
|
1914 | =head2 THE IO::Lambda BENCHMARK |
|
|
1915 | |
|
|
1916 | Recently I was told about the benchmark in the IO::Lambda manpage, which |
|
|
1917 | could be misinterpreted to make AnyEvent look bad. In fact, the benchmark |
|
|
1918 | simply compares IO::Lambda with POE, and IO::Lambda looks better (which |
|
|
1919 | shouldn't come as a surprise to anybody). As such, the benchmark is |
|
|
1920 | fine, and mostly shows that the AnyEvent backend from IO::Lambda isn't |
|
|
1921 | very optimal. But how would AnyEvent compare when used without the extra |
|
|
1922 | baggage? To explore this, I wrote the equivalent benchmark for AnyEvent. |
|
|
1923 | |
|
|
1924 | The benchmark itself creates an echo-server, and then, for 500 times, |
|
|
1925 | connects to the echo server, sends a line, waits for the reply, and then |
|
|
1926 | creates the next connection. This is a rather bad benchmark, as it doesn't |
|
|
1927 | test the efficiency of the framework or much non-blocking I/O, but it is a |
|
|
1928 | benchmark nevertheless. |
|
|
1929 | |
|
|
1930 | name runtime |
|
|
1931 | Lambda/select 0.330 sec |
|
|
1932 | + optimized 0.122 sec |
|
|
1933 | Lambda/AnyEvent 0.327 sec |
|
|
1934 | + optimized 0.138 sec |
|
|
1935 | Raw sockets/select 0.077 sec |
|
|
1936 | POE/select, components 0.662 sec |
|
|
1937 | POE/select, raw sockets 0.226 sec |
|
|
1938 | POE/select, optimized 0.404 sec |
|
|
1939 | |
|
|
1940 | AnyEvent/select/nb 0.085 sec |
|
|
1941 | AnyEvent/EV/nb 0.068 sec |
|
|
1942 | +state machine 0.134 sec |
|
|
1943 | |
|
|
1944 | The benchmark is also a bit unfair (my fault): the IO::Lambda/POE |
|
|
1945 | benchmarks actually make blocking connects and use 100% blocking I/O, |
|
|
1946 | defeating the purpose of an event-based solution. All of the newly |
|
|
1947 | written AnyEvent benchmarks use 100% non-blocking connects (using |
|
|
1948 | AnyEvent::Socket::tcp_connect and the asynchronous pure perl DNS |
|
|
1949 | resolver), so AnyEvent is at a disadvantage here, as non-blocking connects |
|
|
1950 | generally require a lot more bookkeeping and event handling than blocking |
|
|
1951 | connects (which involve a single syscall only). |
|
|
1952 | |
|
|
1953 | The last AnyEvent benchmark additionally uses L<AnyEvent::Handle>, which |
|
|
1954 | offers similar expressive power as POE and IO::Lambda, using conventional |
|
|
1955 | Perl syntax. This means that both the echo server and the client are 100% |
|
|
1956 | non-blocking, further placing it at a disadvantage. |
|
|
1957 | |
|
|
1958 | As you can see, the AnyEvent + EV combination even beats the |
|
|
1959 | hand-optimised "raw sockets benchmark", while AnyEvent + its pure perl |
|
|
1960 | backend easily beats IO::Lambda and POE. |
|
|
1961 | |
|
|
1962 | And even the 100% non-blocking version written using the high-level (and |
|
|
1963 | slow :) L<AnyEvent::Handle> abstraction beats both POE and IO::Lambda by a |
|
|
1964 | large margin, even though it does all of DNS, tcp-connect and socket I/O |
|
|
1965 | in a non-blocking way. |
|
|
1966 | |
|
|
1967 | The two AnyEvent benchmarks programs can be found as F<eg/ae0.pl> and |
|
|
1968 | F<eg/ae2.pl> in the AnyEvent distribution, the remaining benchmarks are |
|
|
1969 | part of the IO::lambda distribution and were used without any changes. |
|
|
1970 | |
1758 | |
1971 | |
1759 | =head1 SIGNALS |
1972 | =head1 SIGNALS |
1760 | |
1973 | |
1761 | AnyEvent currently installs handlers for these signals: |
1974 | AnyEvent currently installs handlers for these signals: |
1762 | |
1975 | |
… | |
… | |
1765 | =item SIGCHLD |
1978 | =item SIGCHLD |
1766 | |
1979 | |
1767 | A handler for C<SIGCHLD> is installed by AnyEvent's child watcher |
1980 | A handler for C<SIGCHLD> is installed by AnyEvent's child watcher |
1768 | emulation for event loops that do not support them natively. Also, some |
1981 | emulation for event loops that do not support them natively. Also, some |
1769 | event loops install a similar handler. |
1982 | event loops install a similar handler. |
|
|
1983 | |
|
|
1984 | If, when AnyEvent is loaded, SIGCHLD is set to IGNORE, then AnyEvent will |
|
|
1985 | reset it to default, to avoid losing child exit statuses. |
1770 | |
1986 | |
1771 | =item SIGPIPE |
1987 | =item SIGPIPE |
1772 | |
1988 | |
1773 | A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef> |
1989 | A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef> |
1774 | when AnyEvent gets loaded. |
1990 | when AnyEvent gets loaded. |
… | |
… | |
1786 | |
2002 | |
1787 | =back |
2003 | =back |
1788 | |
2004 | |
1789 | =cut |
2005 | =cut |
1790 | |
2006 | |
|
|
2007 | undef $SIG{CHLD} |
|
|
2008 | if $SIG{CHLD} eq 'IGNORE'; |
|
|
2009 | |
1791 | $SIG{PIPE} = sub { } |
2010 | $SIG{PIPE} = sub { } |
1792 | unless defined $SIG{PIPE}; |
2011 | unless defined $SIG{PIPE}; |
1793 | |
|
|
1794 | |
2012 | |
1795 | =head1 FORK |
2013 | =head1 FORK |
1796 | |
2014 | |
1797 | Most event libraries are not fork-safe. The ones who are usually are |
2015 | Most event libraries are not fork-safe. The ones who are usually are |
1798 | because they rely on inefficient but fork-safe C<select> or C<poll> |
2016 | because they rely on inefficient but fork-safe C<select> or C<poll> |
… | |
… | |
1819 | use AnyEvent; |
2037 | use AnyEvent; |
1820 | |
2038 | |
1821 | Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can |
2039 | Similar considerations apply to $ENV{PERL_ANYEVENT_VERBOSE}, as that can |
1822 | be used to probe what backend is used and gain other information (which is |
2040 | be used to probe what backend is used and gain other information (which is |
1823 | probably even less useful to an attacker than PERL_ANYEVENT_MODEL), and |
2041 | probably even less useful to an attacker than PERL_ANYEVENT_MODEL), and |
1824 | $ENV{PERL_ANYEGENT_STRICT}. |
2042 | $ENV{PERL_ANYEVENT_STRICT}. |
|
|
2043 | |
|
|
2044 | Note that AnyEvent will remove I<all> environment variables starting with |
|
|
2045 | C<PERL_ANYEVENT_> from C<%ENV> when it is loaded while taint mode is |
|
|
2046 | enabled. |
1825 | |
2047 | |
1826 | |
2048 | |
1827 | =head1 BUGS |
2049 | =head1 BUGS |
1828 | |
2050 | |
1829 | Perl 5.8 has numerous memleaks that sometimes hit this module and are hard |
2051 | Perl 5.8 has numerous memleaks that sometimes hit this module and are hard |
1830 | to work around. If you suffer from memleaks, first upgrade to Perl 5.10 |
2052 | to work around. If you suffer from memleaks, first upgrade to Perl 5.10 |
1831 | and check wether the leaks still show up. (Perl 5.10.0 has other annoying |
2053 | and check wether the leaks still show up. (Perl 5.10.0 has other annoying |
1832 | mamleaks, such as leaking on C<map> and C<grep> but it is usually not as |
2054 | memleaks, such as leaking on C<map> and C<grep> but it is usually not as |
1833 | pronounced). |
2055 | pronounced). |
1834 | |
2056 | |
1835 | |
2057 | |
1836 | =head1 SEE ALSO |
2058 | =head1 SEE ALSO |
1837 | |
2059 | |