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 |
… | |
… | |
340 | =head2 CHILD PROCESS WATCHERS |
375 | =head2 CHILD PROCESS WATCHERS |
341 | |
376 | |
342 | You can also watch on a child process exit and catch its exit status. |
377 | You can also watch on a child process exit and catch its exit status. |
343 | |
378 | |
344 | The child process is specified by the C<pid> argument (if set to C<0>, it |
379 | The child process is specified by the C<pid> argument (if set to C<0>, it |
345 | watches for any child process exit). The watcher will trigger as often |
380 | watches for any child process exit). The watcher will triggered only when |
346 | as status change for the child are received. This works by installing a |
381 | the child process has finished and an exit status is available, not on |
347 | signal handler for C<SIGCHLD>. The callback will be called with the pid |
382 | any trace events (stopped/continued). |
348 | and exit status (as returned by waitpid), so unlike other watcher types, |
383 | |
349 | you I<can> rely on child watcher callback arguments. |
384 | The callback will be called with the pid and exit status (as returned by |
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385 | waitpid), so unlike other watcher types, you I<can> rely on child watcher |
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386 | callback arguments. |
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387 | |
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388 | This watcher type works by installing a signal handler for C<SIGCHLD>, |
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389 | and since it cannot be shared, nothing else should use SIGCHLD or reap |
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390 | random child processes (waiting for specific child processes, e.g. inside |
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391 | C<system>, is just fine). |
350 | |
392 | |
351 | 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 |
352 | 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 |
353 | have exited already (and no SIGCHLD will be sent anymore). |
395 | have exited already (and no SIGCHLD will be sent anymore). |
354 | |
396 | |
… | |
… | |
376 | ); |
418 | ); |
377 | |
419 | |
378 | # do something else, then wait for process exit |
420 | # do something else, then wait for process exit |
379 | $done->recv; |
421 | $done->recv; |
380 | |
422 | |
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423 | =head2 IDLE WATCHERS |
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424 | |
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425 | Sometimes there is a need to do something, but it is not so important |
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426 | to do it instantly, but only when there is nothing better to do. This |
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427 | "nothing better to do" is usually defined to be "no other events need |
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428 | attention by the event loop". |
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429 | |
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430 | Idle watchers ideally get invoked when the event loop has nothing |
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431 | better to do, just before it would block the process to wait for new |
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432 | events. Instead of blocking, the idle watcher is invoked. |
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433 | |
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434 | Most event loops unfortunately do not really support idle watchers (only |
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435 | EV, Event and Glib do it in a usable fashion) - for the rest, AnyEvent |
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436 | will simply call the callback "from time to time". |
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437 | |
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438 | Example: read lines from STDIN, but only process them when the |
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439 | program is otherwise idle: |
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440 | |
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441 | my @lines; # read data |
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442 | my $idle_w; |
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443 | my $io_w = AnyEvent->io (fh => \*STDIN, poll => 'r', cb => sub { |
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444 | push @lines, scalar <STDIN>; |
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445 | |
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446 | # start an idle watcher, if not already done |
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447 | $idle_w ||= AnyEvent->idle (cb => sub { |
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448 | # handle only one line, when there are lines left |
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449 | if (my $line = shift @lines) { |
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450 | print "handled when idle: $line"; |
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451 | } else { |
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452 | # otherwise disable the idle watcher again |
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453 | undef $idle_w; |
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454 | } |
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455 | }); |
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456 | }); |
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457 | |
381 | =head2 CONDITION VARIABLES |
458 | =head2 CONDITION VARIABLES |
382 | |
459 | |
383 | If you are familiar with some event loops you will know that all of them |
460 | If you are familiar with some event loops you will know that all of them |
384 | require you to run some blocking "loop", "run" or similar function that |
461 | require you to run some blocking "loop", "run" or similar function that |
385 | will actively watch for new events and call your callbacks. |
462 | will actively watch for new events and call your callbacks. |
… | |
… | |
818 | =item L<AnyEvent::IGS> |
895 | =item L<AnyEvent::IGS> |
819 | |
896 | |
820 | A non-blocking interface to the Internet Go Server protocol (used by |
897 | A non-blocking interface to the Internet Go Server protocol (used by |
821 | L<App::IGS>). |
898 | L<App::IGS>). |
822 | |
899 | |
823 | =item L<Net::IRC3> |
900 | =item L<AnyEvent::IRC> |
824 | |
901 | |
825 | AnyEvent based IRC client module family. |
902 | AnyEvent based IRC client module family (replacing the older Net::IRC3). |
826 | |
903 | |
827 | =item L<Net::XMPP2> |
904 | =item L<Net::XMPP2> |
828 | |
905 | |
829 | AnyEvent based XMPP (Jabber protocol) module family. |
906 | AnyEvent based XMPP (Jabber protocol) module family. |
830 | |
907 | |
… | |
… | |
850 | =cut |
927 | =cut |
851 | |
928 | |
852 | package AnyEvent; |
929 | package AnyEvent; |
853 | |
930 | |
854 | no warnings; |
931 | no warnings; |
855 | use strict; |
932 | use strict qw(vars subs); |
856 | |
933 | |
857 | use Carp; |
934 | use Carp; |
858 | |
935 | |
859 | our $VERSION = 4.233; |
936 | our $VERSION = 4.411; |
860 | our $MODEL; |
937 | our $MODEL; |
861 | |
938 | |
862 | our $AUTOLOAD; |
939 | our $AUTOLOAD; |
863 | our @ISA; |
940 | our @ISA; |
864 | |
941 | |
… | |
… | |
896 | [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza |
973 | [POE::Kernel:: => AnyEvent::Impl::POE::], # lasciate ogni speranza |
897 | [Wx:: => AnyEvent::Impl::POE::], |
974 | [Wx:: => AnyEvent::Impl::POE::], |
898 | [Prima:: => AnyEvent::Impl::POE::], |
975 | [Prima:: => AnyEvent::Impl::POE::], |
899 | ); |
976 | ); |
900 | |
977 | |
901 | our %method = map +($_ => 1), qw(io timer time now signal child condvar one_event DESTROY); |
978 | our %method = map +($_ => 1), |
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979 | qw(io timer time now now_update signal child idle condvar one_event DESTROY); |
902 | |
980 | |
903 | our @post_detect; |
981 | our @post_detect; |
904 | |
982 | |
905 | sub post_detect(&) { |
983 | sub post_detect(&) { |
906 | my ($cb) = @_; |
984 | my ($cb) = @_; |
… | |
… | |
911 | 1 |
989 | 1 |
912 | } else { |
990 | } else { |
913 | push @post_detect, $cb; |
991 | push @post_detect, $cb; |
914 | |
992 | |
915 | defined wantarray |
993 | defined wantarray |
916 | ? bless \$cb, "AnyEvent::Util::PostDetect" |
994 | ? bless \$cb, "AnyEvent::Util::postdetect" |
917 | : () |
995 | : () |
918 | } |
996 | } |
919 | } |
997 | } |
920 | |
998 | |
921 | sub AnyEvent::Util::PostDetect::DESTROY { |
999 | sub AnyEvent::Util::postdetect::DESTROY { |
922 | @post_detect = grep $_ != ${$_[0]}, @post_detect; |
1000 | @post_detect = grep $_ != ${$_[0]}, @post_detect; |
923 | } |
1001 | } |
924 | |
1002 | |
925 | sub detect() { |
1003 | sub detect() { |
926 | unless ($MODEL) { |
1004 | unless ($MODEL) { |
… | |
… | |
963 | last; |
1041 | last; |
964 | } |
1042 | } |
965 | } |
1043 | } |
966 | |
1044 | |
967 | $MODEL |
1045 | $MODEL |
968 | or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib."; |
1046 | or die "No event module selected for AnyEvent and autodetect failed. Install any one of these modules: EV, Event or Glib.\n"; |
969 | } |
1047 | } |
970 | } |
1048 | } |
971 | |
1049 | |
972 | push @{"$MODEL\::ISA"}, "AnyEvent::Base"; |
1050 | push @{"$MODEL\::ISA"}, "AnyEvent::Base"; |
973 | |
1051 | |
… | |
… | |
997 | # to support binding more than one watcher per filehandle (they usually |
1075 | # to support binding more than one watcher per filehandle (they usually |
998 | # allow only one watcher per fd, so we dup it to get a different one). |
1076 | # allow only one watcher per fd, so we dup it to get a different one). |
999 | sub _dupfh($$$$) { |
1077 | sub _dupfh($$$$) { |
1000 | my ($poll, $fh, $r, $w) = @_; |
1078 | my ($poll, $fh, $r, $w) = @_; |
1001 | |
1079 | |
1002 | require Fcntl; |
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1003 | |
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1004 | # cygwin requires the fh mode to be matching, unix doesn't |
1080 | # cygwin requires the fh mode to be matching, unix doesn't |
1005 | my ($rw, $mode) = $poll eq "r" ? ($r, "<") |
1081 | my ($rw, $mode) = $poll eq "r" ? ($r, "<") |
1006 | : $poll eq "w" ? ($w, ">") |
1082 | : $poll eq "w" ? ($w, ">") |
1007 | : Carp::croak "AnyEvent->io requires poll set to either 'r' or 'w'"; |
1083 | : Carp::croak "AnyEvent->io requires poll set to either 'r' or 'w'"; |
1008 | |
1084 | |
1009 | open my $fh2, "$mode&" . fileno $fh |
1085 | open my $fh2, "$mode&" . fileno $fh |
1010 | or die "cannot dup() filehandle: $!"; |
1086 | or die "cannot dup() filehandle: $!,"; |
1011 | |
1087 | |
1012 | # we assume CLOEXEC is already set by perl in all important cases |
1088 | # we assume CLOEXEC is already set by perl in all important cases |
1013 | |
1089 | |
1014 | ($fh2, $rw) |
1090 | ($fh2, $rw) |
1015 | } |
1091 | } |
1016 | |
1092 | |
1017 | package AnyEvent::Base; |
1093 | package AnyEvent::Base; |
1018 | |
1094 | |
1019 | # default implementation for now and time |
1095 | # default implementations for many methods |
1020 | |
1096 | |
1021 | BEGIN { |
1097 | BEGIN { |
1022 | if (eval "use Time::HiRes (); time (); 1") { |
1098 | if (eval "use Time::HiRes (); Time::HiRes::time (); 1") { |
1023 | *_time = \&Time::HiRes::time; |
1099 | *_time = \&Time::HiRes::time; |
1024 | # if (eval "use POSIX (); (POSIX::times())... |
1100 | # if (eval "use POSIX (); (POSIX::times())... |
1025 | } else { |
1101 | } else { |
1026 | *_time = \&CORE::time; # epic fail |
1102 | *_time = sub { time }; # epic fail |
1027 | } |
1103 | } |
1028 | } |
1104 | } |
1029 | |
1105 | |
1030 | sub time { _time } |
1106 | sub time { _time } |
1031 | sub now { _time } |
1107 | sub now { _time } |
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1108 | sub now_update { } |
1032 | |
1109 | |
1033 | # default implementation for ->condvar |
1110 | # default implementation for ->condvar |
1034 | |
1111 | |
1035 | sub condvar { |
1112 | sub condvar { |
1036 | bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, AnyEvent::CondVar:: |
1113 | bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, "AnyEvent::CondVar" |
1037 | } |
1114 | } |
1038 | |
1115 | |
1039 | # default implementation for ->signal |
1116 | # default implementation for ->signal |
1040 | |
1117 | |
1041 | our %SIG_CB; |
1118 | our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO); |
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1119 | |
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1120 | sub _signal_exec { |
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1121 | sysread $SIGPIPE_R, my $dummy, 4; |
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1122 | |
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1123 | while (%SIG_EV) { |
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1124 | for (keys %SIG_EV) { |
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1125 | delete $SIG_EV{$_}; |
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1126 | $_->() for values %{ $SIG_CB{$_} || {} }; |
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1127 | } |
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1128 | } |
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1129 | } |
1042 | |
1130 | |
1043 | sub signal { |
1131 | sub signal { |
1044 | my (undef, %arg) = @_; |
1132 | my (undef, %arg) = @_; |
1045 | |
1133 | |
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1134 | unless ($SIGPIPE_R) { |
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1135 | require Fcntl; |
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1136 | |
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1137 | if (AnyEvent::WIN32) { |
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1138 | require AnyEvent::Util; |
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1139 | |
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1140 | ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe (); |
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1141 | AnyEvent::Util::fh_nonblocking ($SIGPIPE_R) if $SIGPIPE_R; |
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1142 | AnyEvent::Util::fh_nonblocking ($SIGPIPE_W) if $SIGPIPE_W; # just in case |
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1143 | } else { |
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1144 | pipe $SIGPIPE_R, $SIGPIPE_W; |
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1145 | fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R; |
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1146 | fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case |
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1147 | |
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1148 | # not strictly required, as $^F is normally 2, but let's make sure... |
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1149 | fcntl $SIGPIPE_R, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; |
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1150 | fcntl $SIGPIPE_W, &Fcntl::F_SETFD, &Fcntl::FD_CLOEXEC; |
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1151 | } |
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1152 | |
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1153 | $SIGPIPE_R |
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1154 | or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n"; |
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1155 | |
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1156 | $SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec); |
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1157 | } |
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1158 | |
1046 | my $signal = uc $arg{signal} |
1159 | my $signal = uc $arg{signal} |
1047 | or Carp::croak "required option 'signal' is missing"; |
1160 | or Carp::croak "required option 'signal' is missing"; |
1048 | |
1161 | |
1049 | $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; |
1162 | $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; |
1050 | $SIG{$signal} ||= sub { |
1163 | $SIG{$signal} ||= sub { |
1051 | $_->() for values %{ $SIG_CB{$signal} || {} }; |
1164 | local $!; |
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|
1165 | syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV; |
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|
1166 | undef $SIG_EV{$signal}; |
1052 | }; |
1167 | }; |
1053 | |
1168 | |
1054 | bless [$signal, $arg{cb}], "AnyEvent::Base::Signal" |
1169 | bless [$signal, $arg{cb}], "AnyEvent::Base::signal" |
1055 | } |
1170 | } |
1056 | |
1171 | |
1057 | sub AnyEvent::Base::Signal::DESTROY { |
1172 | sub AnyEvent::Base::signal::DESTROY { |
1058 | my ($signal, $cb) = @{$_[0]}; |
1173 | my ($signal, $cb) = @{$_[0]}; |
1059 | |
1174 | |
1060 | delete $SIG_CB{$signal}{$cb}; |
1175 | delete $SIG_CB{$signal}{$cb}; |
1061 | |
1176 | |
|
|
1177 | # delete doesn't work with older perls - they then |
|
|
1178 | # print weird messages, or just unconditionally exit |
|
|
1179 | # instead of getting the default action. |
1062 | delete $SIG{$signal} unless keys %{ $SIG_CB{$signal} }; |
1180 | undef $SIG{$signal} unless keys %{ $SIG_CB{$signal} }; |
1063 | } |
1181 | } |
1064 | |
1182 | |
1065 | # default implementation for ->child |
1183 | # default implementation for ->child |
1066 | |
1184 | |
1067 | our %PID_CB; |
1185 | our %PID_CB; |
1068 | our $CHLD_W; |
1186 | our $CHLD_W; |
1069 | our $CHLD_DELAY_W; |
1187 | our $CHLD_DELAY_W; |
1070 | our $PID_IDLE; |
|
|
1071 | our $WNOHANG; |
1188 | our $WNOHANG; |
1072 | |
1189 | |
1073 | sub _child_wait { |
1190 | sub _sigchld { |
1074 | while (0 < (my $pid = waitpid -1, $WNOHANG)) { |
1191 | while (0 < (my $pid = waitpid -1, $WNOHANG)) { |
1075 | $_->($pid, $?) for (values %{ $PID_CB{$pid} || {} }), |
1192 | $_->($pid, $?) for (values %{ $PID_CB{$pid} || {} }), |
1076 | (values %{ $PID_CB{0} || {} }); |
1193 | (values %{ $PID_CB{0} || {} }); |
1077 | } |
1194 | } |
1078 | |
|
|
1079 | undef $PID_IDLE; |
|
|
1080 | } |
|
|
1081 | |
|
|
1082 | sub _sigchld { |
|
|
1083 | # make sure we deliver these changes "synchronous" with the event loop. |
|
|
1084 | $CHLD_DELAY_W ||= AnyEvent->timer (after => 0, cb => sub { |
|
|
1085 | undef $CHLD_DELAY_W; |
|
|
1086 | &_child_wait; |
|
|
1087 | }); |
|
|
1088 | } |
1195 | } |
1089 | |
1196 | |
1090 | sub child { |
1197 | sub child { |
1091 | my (undef, %arg) = @_; |
1198 | my (undef, %arg) = @_; |
1092 | |
1199 | |
1093 | defined (my $pid = $arg{pid} + 0) |
1200 | defined (my $pid = $arg{pid} + 0) |
1094 | or Carp::croak "required option 'pid' is missing"; |
1201 | or Carp::croak "required option 'pid' is missing"; |
1095 | |
1202 | |
1096 | $PID_CB{$pid}{$arg{cb}} = $arg{cb}; |
1203 | $PID_CB{$pid}{$arg{cb}} = $arg{cb}; |
1097 | |
1204 | |
1098 | unless ($WNOHANG) { |
|
|
1099 | $WNOHANG = eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1; |
1205 | $WNOHANG ||= eval { local $SIG{__DIE__}; require POSIX; &POSIX::WNOHANG } || 1; |
1100 | } |
|
|
1101 | |
1206 | |
1102 | unless ($CHLD_W) { |
1207 | unless ($CHLD_W) { |
1103 | $CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld); |
1208 | $CHLD_W = AnyEvent->signal (signal => 'CHLD', cb => \&_sigchld); |
1104 | # child could be a zombie already, so make at least one round |
1209 | # child could be a zombie already, so make at least one round |
1105 | &_sigchld; |
1210 | &_sigchld; |
1106 | } |
1211 | } |
1107 | |
1212 | |
1108 | bless [$pid, $arg{cb}], "AnyEvent::Base::Child" |
1213 | bless [$pid, $arg{cb}], "AnyEvent::Base::child" |
1109 | } |
1214 | } |
1110 | |
1215 | |
1111 | sub AnyEvent::Base::Child::DESTROY { |
1216 | sub AnyEvent::Base::child::DESTROY { |
1112 | my ($pid, $cb) = @{$_[0]}; |
1217 | my ($pid, $cb) = @{$_[0]}; |
1113 | |
1218 | |
1114 | delete $PID_CB{$pid}{$cb}; |
1219 | delete $PID_CB{$pid}{$cb}; |
1115 | delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} }; |
1220 | delete $PID_CB{$pid} unless keys %{ $PID_CB{$pid} }; |
1116 | |
1221 | |
1117 | undef $CHLD_W unless keys %PID_CB; |
1222 | undef $CHLD_W unless keys %PID_CB; |
|
|
1223 | } |
|
|
1224 | |
|
|
1225 | # idle emulation is done by simply using a timer, regardless |
|
|
1226 | # of whether the process is idle or not, and not letting |
|
|
1227 | # the callback use more than 50% of the time. |
|
|
1228 | sub idle { |
|
|
1229 | my (undef, %arg) = @_; |
|
|
1230 | |
|
|
1231 | my ($cb, $w, $rcb) = $arg{cb}; |
|
|
1232 | |
|
|
1233 | $rcb = sub { |
|
|
1234 | if ($cb) { |
|
|
1235 | $w = _time; |
|
|
1236 | &$cb; |
|
|
1237 | $w = _time - $w; |
|
|
1238 | |
|
|
1239 | # never use more then 50% of the time for the idle watcher, |
|
|
1240 | # within some limits |
|
|
1241 | $w = 0.0001 if $w < 0.0001; |
|
|
1242 | $w = 5 if $w > 5; |
|
|
1243 | |
|
|
1244 | $w = AnyEvent->timer (after => $w, cb => $rcb); |
|
|
1245 | } else { |
|
|
1246 | # clean up... |
|
|
1247 | undef $w; |
|
|
1248 | undef $rcb; |
|
|
1249 | } |
|
|
1250 | }; |
|
|
1251 | |
|
|
1252 | $w = AnyEvent->timer (after => 0.05, cb => $rcb); |
|
|
1253 | |
|
|
1254 | bless \\$cb, "AnyEvent::Base::idle" |
|
|
1255 | } |
|
|
1256 | |
|
|
1257 | sub AnyEvent::Base::idle::DESTROY { |
|
|
1258 | undef $${$_[0]}; |
1118 | } |
1259 | } |
1119 | |
1260 | |
1120 | package AnyEvent::CondVar; |
1261 | package AnyEvent::CondVar; |
1121 | |
1262 | |
1122 | our @ISA = AnyEvent::CondVar::Base::; |
1263 | our @ISA = AnyEvent::CondVar::Base::; |
… | |
… | |
1174 | } |
1315 | } |
1175 | |
1316 | |
1176 | # undocumented/compatibility with pre-3.4 |
1317 | # undocumented/compatibility with pre-3.4 |
1177 | *broadcast = \&send; |
1318 | *broadcast = \&send; |
1178 | *wait = \&_wait; |
1319 | *wait = \&_wait; |
|
|
1320 | |
|
|
1321 | =head1 ERROR AND EXCEPTION HANDLING |
|
|
1322 | |
|
|
1323 | In general, AnyEvent does not do any error handling - it relies on the |
|
|
1324 | caller to do that if required. The L<AnyEvent::Strict> module (see also |
|
|
1325 | the C<PERL_ANYEVENT_STRICT> environment variable, below) provides strict |
|
|
1326 | checking of all AnyEvent methods, however, which is highly useful during |
|
|
1327 | development. |
|
|
1328 | |
|
|
1329 | As for exception handling (i.e. runtime errors and exceptions thrown while |
|
|
1330 | executing a callback), this is not only highly event-loop specific, but |
|
|
1331 | also not in any way wrapped by this module, as this is the job of the main |
|
|
1332 | program. |
|
|
1333 | |
|
|
1334 | The pure perl event loop simply re-throws the exception (usually |
|
|
1335 | within C<< condvar->recv >>), the L<Event> and L<EV> modules call C<< |
|
|
1336 | $Event/EV::DIED->() >>, L<Glib> uses C<< install_exception_handler >> and |
|
|
1337 | so on. |
|
|
1338 | |
|
|
1339 | =head1 ENVIRONMENT VARIABLES |
|
|
1340 | |
|
|
1341 | The following environment variables are used by this module or its |
|
|
1342 | submodules: |
|
|
1343 | |
|
|
1344 | =over 4 |
|
|
1345 | |
|
|
1346 | =item C<PERL_ANYEVENT_VERBOSE> |
|
|
1347 | |
|
|
1348 | By default, AnyEvent will be completely silent except in fatal |
|
|
1349 | conditions. You can set this environment variable to make AnyEvent more |
|
|
1350 | talkative. |
|
|
1351 | |
|
|
1352 | When set to C<1> or higher, causes AnyEvent to warn about unexpected |
|
|
1353 | conditions, such as not being able to load the event model specified by |
|
|
1354 | C<PERL_ANYEVENT_MODEL>. |
|
|
1355 | |
|
|
1356 | When set to C<2> or higher, cause AnyEvent to report to STDERR which event |
|
|
1357 | model it chooses. |
|
|
1358 | |
|
|
1359 | =item C<PERL_ANYEVENT_STRICT> |
|
|
1360 | |
|
|
1361 | AnyEvent does not do much argument checking by default, as thorough |
|
|
1362 | argument checking is very costly. Setting this variable to a true value |
|
|
1363 | will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly |
|
|
1364 | check the arguments passed to most method calls. If it finds any problems |
|
|
1365 | it will croak. |
|
|
1366 | |
|
|
1367 | In other words, enables "strict" mode. |
|
|
1368 | |
|
|
1369 | Unlike C<use strict>, it is definitely recommended ot keep it off in |
|
|
1370 | production. Keeping C<PERL_ANYEVENT_STRICT=1> in your environment while |
|
|
1371 | developing programs can be very useful, however. |
|
|
1372 | |
|
|
1373 | =item C<PERL_ANYEVENT_MODEL> |
|
|
1374 | |
|
|
1375 | This can be used to specify the event model to be used by AnyEvent, before |
|
|
1376 | auto detection and -probing kicks in. It must be a string consisting |
|
|
1377 | entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended |
|
|
1378 | and the resulting module name is loaded and if the load was successful, |
|
|
1379 | used as event model. If it fails to load AnyEvent will proceed with |
|
|
1380 | auto detection and -probing. |
|
|
1381 | |
|
|
1382 | This functionality might change in future versions. |
|
|
1383 | |
|
|
1384 | For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you |
|
|
1385 | could start your program like this: |
|
|
1386 | |
|
|
1387 | PERL_ANYEVENT_MODEL=Perl perl ... |
|
|
1388 | |
|
|
1389 | =item C<PERL_ANYEVENT_PROTOCOLS> |
|
|
1390 | |
|
|
1391 | Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences |
|
|
1392 | for IPv4 or IPv6. The default is unspecified (and might change, or be the result |
|
|
1393 | of auto probing). |
|
|
1394 | |
|
|
1395 | Must be set to a comma-separated list of protocols or address families, |
|
|
1396 | current supported: C<ipv4> and C<ipv6>. Only protocols mentioned will be |
|
|
1397 | used, and preference will be given to protocols mentioned earlier in the |
|
|
1398 | list. |
|
|
1399 | |
|
|
1400 | This variable can effectively be used for denial-of-service attacks |
|
|
1401 | against local programs (e.g. when setuid), although the impact is likely |
|
|
1402 | small, as the program has to handle conenction and other failures anyways. |
|
|
1403 | |
|
|
1404 | Examples: C<PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6> - prefer IPv4 over IPv6, |
|
|
1405 | but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4> |
|
|
1406 | - only support IPv4, never try to resolve or contact IPv6 |
|
|
1407 | addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or |
|
|
1408 | IPv6, but prefer IPv6 over IPv4. |
|
|
1409 | |
|
|
1410 | =item C<PERL_ANYEVENT_EDNS0> |
|
|
1411 | |
|
|
1412 | Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension |
|
|
1413 | for DNS. This extension is generally useful to reduce DNS traffic, but |
|
|
1414 | some (broken) firewalls drop such DNS packets, which is why it is off by |
|
|
1415 | default. |
|
|
1416 | |
|
|
1417 | Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce |
|
|
1418 | EDNS0 in its DNS requests. |
|
|
1419 | |
|
|
1420 | =item C<PERL_ANYEVENT_MAX_FORKS> |
|
|
1421 | |
|
|
1422 | The maximum number of child processes that C<AnyEvent::Util::fork_call> |
|
|
1423 | will create in parallel. |
|
|
1424 | |
|
|
1425 | =back |
1179 | |
1426 | |
1180 | =head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE |
1427 | =head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE |
1181 | |
1428 | |
1182 | This is an advanced topic that you do not normally need to use AnyEvent in |
1429 | This is an advanced topic that you do not normally need to use AnyEvent in |
1183 | a module. This section is only of use to event loop authors who want to |
1430 | a module. This section is only of use to event loop authors who want to |
… | |
… | |
1217 | |
1464 | |
1218 | I<rxvt-unicode> also cheats a bit by not providing blocking access to |
1465 | I<rxvt-unicode> also cheats a bit by not providing blocking access to |
1219 | condition variables: code blocking while waiting for a condition will |
1466 | condition variables: code blocking while waiting for a condition will |
1220 | C<die>. This still works with most modules/usages, and blocking calls must |
1467 | C<die>. This still works with most modules/usages, and blocking calls must |
1221 | not be done in an interactive application, so it makes sense. |
1468 | not be done in an interactive application, so it makes sense. |
1222 | |
|
|
1223 | =head1 ENVIRONMENT VARIABLES |
|
|
1224 | |
|
|
1225 | The following environment variables are used by this module: |
|
|
1226 | |
|
|
1227 | =over 4 |
|
|
1228 | |
|
|
1229 | =item C<PERL_ANYEVENT_VERBOSE> |
|
|
1230 | |
|
|
1231 | By default, AnyEvent will be completely silent except in fatal |
|
|
1232 | conditions. You can set this environment variable to make AnyEvent more |
|
|
1233 | talkative. |
|
|
1234 | |
|
|
1235 | When set to C<1> or higher, causes AnyEvent to warn about unexpected |
|
|
1236 | conditions, such as not being able to load the event model specified by |
|
|
1237 | C<PERL_ANYEVENT_MODEL>. |
|
|
1238 | |
|
|
1239 | When set to C<2> or higher, cause AnyEvent to report to STDERR which event |
|
|
1240 | model it chooses. |
|
|
1241 | |
|
|
1242 | =item C<PERL_ANYEVENT_STRICT> |
|
|
1243 | |
|
|
1244 | AnyEvent does not do much argument checking by default, as thorough |
|
|
1245 | argument checking is very costly. Setting this variable to a true value |
|
|
1246 | will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly |
|
|
1247 | check the arguments passed to most method calls. If it finds any problems |
|
|
1248 | it will croak. |
|
|
1249 | |
|
|
1250 | In other words, enables "strict" mode. |
|
|
1251 | |
|
|
1252 | Unlike C<use strict> it is definitely recommended ot keep it off in |
|
|
1253 | production. |
|
|
1254 | |
|
|
1255 | =item C<PERL_ANYEVENT_MODEL> |
|
|
1256 | |
|
|
1257 | This can be used to specify the event model to be used by AnyEvent, before |
|
|
1258 | auto detection and -probing kicks in. It must be a string consisting |
|
|
1259 | entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended |
|
|
1260 | and the resulting module name is loaded and if the load was successful, |
|
|
1261 | used as event model. If it fails to load AnyEvent will proceed with |
|
|
1262 | auto detection and -probing. |
|
|
1263 | |
|
|
1264 | This functionality might change in future versions. |
|
|
1265 | |
|
|
1266 | For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you |
|
|
1267 | could start your program like this: |
|
|
1268 | |
|
|
1269 | PERL_ANYEVENT_MODEL=Perl perl ... |
|
|
1270 | |
|
|
1271 | =item C<PERL_ANYEVENT_PROTOCOLS> |
|
|
1272 | |
|
|
1273 | Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences |
|
|
1274 | for IPv4 or IPv6. The default is unspecified (and might change, or be the result |
|
|
1275 | of auto probing). |
|
|
1276 | |
|
|
1277 | Must be set to a comma-separated list of protocols or address families, |
|
|
1278 | current supported: C<ipv4> and C<ipv6>. Only protocols mentioned will be |
|
|
1279 | used, and preference will be given to protocols mentioned earlier in the |
|
|
1280 | list. |
|
|
1281 | |
|
|
1282 | This variable can effectively be used for denial-of-service attacks |
|
|
1283 | against local programs (e.g. when setuid), although the impact is likely |
|
|
1284 | small, as the program has to handle connection errors already- |
|
|
1285 | |
|
|
1286 | Examples: C<PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6> - prefer IPv4 over IPv6, |
|
|
1287 | but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4> |
|
|
1288 | - only support IPv4, never try to resolve or contact IPv6 |
|
|
1289 | addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or |
|
|
1290 | IPv6, but prefer IPv6 over IPv4. |
|
|
1291 | |
|
|
1292 | =item C<PERL_ANYEVENT_EDNS0> |
|
|
1293 | |
|
|
1294 | Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension |
|
|
1295 | for DNS. This extension is generally useful to reduce DNS traffic, but |
|
|
1296 | some (broken) firewalls drop such DNS packets, which is why it is off by |
|
|
1297 | default. |
|
|
1298 | |
|
|
1299 | Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce |
|
|
1300 | EDNS0 in its DNS requests. |
|
|
1301 | |
|
|
1302 | =item C<PERL_ANYEVENT_MAX_FORKS> |
|
|
1303 | |
|
|
1304 | The maximum number of child processes that C<AnyEvent::Util::fork_call> |
|
|
1305 | will create in parallel. |
|
|
1306 | |
|
|
1307 | =back |
|
|
1308 | |
1469 | |
1309 | =head1 EXAMPLE PROGRAM |
1470 | =head1 EXAMPLE PROGRAM |
1310 | |
1471 | |
1311 | The following program uses an I/O watcher to read data from STDIN, a timer |
1472 | The following program uses an I/O watcher to read data from STDIN, a timer |
1312 | to display a message once per second, and a condition variable to quit the |
1473 | to display a message once per second, and a condition variable to quit the |
… | |
… | |
1506 | watcher. |
1667 | watcher. |
1507 | |
1668 | |
1508 | =head3 Results |
1669 | =head3 Results |
1509 | |
1670 | |
1510 | name watchers bytes create invoke destroy comment |
1671 | name watchers bytes create invoke destroy comment |
1511 | EV/EV 400000 244 0.56 0.46 0.31 EV native interface |
1672 | EV/EV 400000 224 0.47 0.35 0.27 EV native interface |
1512 | EV/Any 100000 244 2.50 0.46 0.29 EV + AnyEvent watchers |
1673 | EV/Any 100000 224 2.88 0.34 0.27 EV + AnyEvent watchers |
1513 | CoroEV/Any 100000 244 2.49 0.44 0.29 coroutines + Coro::Signal |
1674 | CoroEV/Any 100000 224 2.85 0.35 0.28 coroutines + Coro::Signal |
1514 | Perl/Any 100000 513 4.92 0.87 1.12 pure perl implementation |
1675 | Perl/Any 100000 452 4.13 0.73 0.95 pure perl implementation |
1515 | Event/Event 16000 516 31.88 31.30 0.85 Event native interface |
1676 | Event/Event 16000 517 32.20 31.80 0.81 Event native interface |
1516 | Event/Any 16000 590 35.75 31.42 1.08 Event + AnyEvent watchers |
1677 | Event/Any 16000 590 35.85 31.55 1.06 Event + AnyEvent watchers |
1517 | Glib/Any 16000 1357 98.22 12.41 54.00 quadratic behaviour |
1678 | Glib/Any 16000 1357 102.33 12.31 51.00 quadratic behaviour |
1518 | Tk/Any 2000 1860 26.97 67.98 14.00 SEGV with >> 2000 watchers |
1679 | Tk/Any 2000 1860 27.20 66.31 14.00 SEGV with >> 2000 watchers |
1519 | POE/Event 2000 6644 108.64 736.02 14.73 via POE::Loop::Event |
1680 | POE/Event 2000 6328 109.99 751.67 14.02 via POE::Loop::Event |
1520 | POE/Select 2000 6343 94.13 809.12 565.96 via POE::Loop::Select |
1681 | POE/Select 2000 6027 94.54 809.13 579.80 via POE::Loop::Select |
1521 | |
1682 | |
1522 | =head3 Discussion |
1683 | =head3 Discussion |
1523 | |
1684 | |
1524 | The benchmark does I<not> measure scalability of the event loop very |
1685 | The benchmark does I<not> measure scalability of the event loop very |
1525 | well. For example, a select-based event loop (such as the pure perl one) |
1686 | well. For example, a select-based event loop (such as the pure perl one) |
… | |
… | |
1727 | watchers, as the management overhead dominates. |
1888 | watchers, as the management overhead dominates. |
1728 | |
1889 | |
1729 | =back |
1890 | =back |
1730 | |
1891 | |
1731 | |
1892 | |
|
|
1893 | =head1 SIGNALS |
|
|
1894 | |
|
|
1895 | AnyEvent currently installs handlers for these signals: |
|
|
1896 | |
|
|
1897 | =over 4 |
|
|
1898 | |
|
|
1899 | =item SIGCHLD |
|
|
1900 | |
|
|
1901 | A handler for C<SIGCHLD> is installed by AnyEvent's child watcher |
|
|
1902 | emulation for event loops that do not support them natively. Also, some |
|
|
1903 | event loops install a similar handler. |
|
|
1904 | |
|
|
1905 | =item SIGPIPE |
|
|
1906 | |
|
|
1907 | A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef> |
|
|
1908 | when AnyEvent gets loaded. |
|
|
1909 | |
|
|
1910 | The rationale for this is that AnyEvent users usually do not really depend |
|
|
1911 | on SIGPIPE delivery (which is purely an optimisation for shell use, or |
|
|
1912 | badly-written programs), but C<SIGPIPE> can cause spurious and rare |
|
|
1913 | program exits as a lot of people do not expect C<SIGPIPE> when writing to |
|
|
1914 | some random socket. |
|
|
1915 | |
|
|
1916 | The rationale for installing a no-op handler as opposed to ignoring it is |
|
|
1917 | that this way, the handler will be restored to defaults on exec. |
|
|
1918 | |
|
|
1919 | Feel free to install your own handler, or reset it to defaults. |
|
|
1920 | |
|
|
1921 | =back |
|
|
1922 | |
|
|
1923 | =cut |
|
|
1924 | |
|
|
1925 | $SIG{PIPE} = sub { } |
|
|
1926 | unless defined $SIG{PIPE}; |
|
|
1927 | |
|
|
1928 | |
1732 | =head1 FORK |
1929 | =head1 FORK |
1733 | |
1930 | |
1734 | Most event libraries are not fork-safe. The ones who are usually are |
1931 | Most event libraries are not fork-safe. The ones who are usually are |
1735 | because they rely on inefficient but fork-safe C<select> or C<poll> |
1932 | because they rely on inefficient but fork-safe C<select> or C<poll> |
1736 | calls. Only L<EV> is fully fork-aware. |
1933 | calls. Only L<EV> is fully fork-aware. |
… | |
… | |
1764 | =head1 BUGS |
1961 | =head1 BUGS |
1765 | |
1962 | |
1766 | Perl 5.8 has numerous memleaks that sometimes hit this module and are hard |
1963 | Perl 5.8 has numerous memleaks that sometimes hit this module and are hard |
1767 | to work around. If you suffer from memleaks, first upgrade to Perl 5.10 |
1964 | to work around. If you suffer from memleaks, first upgrade to Perl 5.10 |
1768 | and check wether the leaks still show up. (Perl 5.10.0 has other annoying |
1965 | and check wether the leaks still show up. (Perl 5.10.0 has other annoying |
1769 | mamleaks, such as leaking on C<map> and C<grep> but it is usually not as |
1966 | memleaks, such as leaking on C<map> and C<grep> but it is usually not as |
1770 | pronounced). |
1967 | pronounced). |
1771 | |
1968 | |
1772 | |
1969 | |
1773 | =head1 SEE ALSO |
1970 | =head1 SEE ALSO |
1774 | |
1971 | |