… | |
… | |
6 | |
6 | |
7 | =head1 SYNOPSIS |
7 | =head1 SYNOPSIS |
8 | |
8 | |
9 | use AnyEvent; |
9 | use AnyEvent; |
10 | |
10 | |
11 | my $w = AnyEvent->io (fh => $fh, poll => "r|w", cb => sub { |
11 | my $w = AnyEvent->io (fh => $fh, poll => "r|w", cb => sub { ... }); |
12 | ... |
|
|
13 | }); |
|
|
14 | |
12 | |
15 | my $w = AnyEvent->timer (after => $seconds, cb => sub { |
13 | my $w = AnyEvent->timer (after => $seconds, cb => sub { ... }); |
|
|
14 | my $w = AnyEvent->timer (after => $seconds, interval => $seconds, cb => ... |
|
|
15 | |
|
|
16 | print AnyEvent->now; # prints current event loop time |
|
|
17 | print AnyEvent->time; # think Time::HiRes::time or simply CORE::time. |
|
|
18 | |
|
|
19 | my $w = AnyEvent->signal (signal => "TERM", cb => sub { ... }); |
|
|
20 | |
|
|
21 | my $w = AnyEvent->child (pid => $pid, cb => sub { |
|
|
22 | my ($pid, $status) = @_; |
16 | ... |
23 | ... |
17 | }); |
24 | }); |
18 | |
25 | |
19 | my $w = AnyEvent->condvar; # stores whether a condition was flagged |
26 | my $w = AnyEvent->condvar; # stores whether a condition was flagged |
20 | $w->send; # wake up current and all future recv's |
27 | $w->send; # wake up current and all future recv's |
21 | $w->recv; # enters "main loop" till $condvar gets ->send |
28 | $w->recv; # enters "main loop" till $condvar gets ->send |
|
|
29 | # use a condvar in callback mode: |
|
|
30 | $w->cb (sub { $_[0]->recv }); |
22 | |
31 | |
23 | =head1 INTRODUCTION/TUTORIAL |
32 | =head1 INTRODUCTION/TUTORIAL |
24 | |
33 | |
25 | This manpage is mainly a reference manual. If you are interested |
34 | This manpage is mainly a reference manual. If you are interested |
26 | in a tutorial or some gentle introduction, have a look at the |
35 | in a tutorial or some gentle introduction, have a look at the |
… | |
… | |
33 | |
42 | |
34 | Executive Summary: AnyEvent is I<compatible>, AnyEvent is I<free of |
43 | Executive Summary: AnyEvent is I<compatible>, AnyEvent is I<free of |
35 | policy> and AnyEvent is I<small and efficient>. |
44 | policy> and AnyEvent is I<small and efficient>. |
36 | |
45 | |
37 | First and foremost, I<AnyEvent is not an event model> itself, it only |
46 | First and foremost, I<AnyEvent is not an event model> itself, it only |
38 | interfaces to whatever event model the main program happens to use in a |
47 | interfaces to whatever event model the main program happens to use, in a |
39 | pragmatic way. For event models and certain classes of immortals alike, |
48 | pragmatic way. For event models and certain classes of immortals alike, |
40 | the statement "there can only be one" is a bitter reality: In general, |
49 | the statement "there can only be one" is a bitter reality: In general, |
41 | only one event loop can be active at the same time in a process. AnyEvent |
50 | only one event loop can be active at the same time in a process. AnyEvent |
42 | helps hiding the differences between those event loops. |
51 | cannot change this, but it can hide the differences between those event |
|
|
52 | loops. |
43 | |
53 | |
44 | The goal of AnyEvent is to offer module authors the ability to do event |
54 | The goal of AnyEvent is to offer module authors the ability to do event |
45 | programming (waiting for I/O or timer events) without subscribing to a |
55 | programming (waiting for I/O or timer events) without subscribing to a |
46 | religion, a way of living, and most importantly: without forcing your |
56 | religion, a way of living, and most importantly: without forcing your |
47 | module users into the same thing by forcing them to use the same event |
57 | module users into the same thing by forcing them to use the same event |
48 | model you use. |
58 | model you use. |
49 | |
59 | |
50 | For modules like POE or IO::Async (which is a total misnomer as it is |
60 | For modules like POE or IO::Async (which is a total misnomer as it is |
51 | actually doing all I/O I<synchronously>...), using them in your module is |
61 | actually doing all I/O I<synchronously>...), using them in your module is |
52 | like joining a cult: After you joined, you are dependent on them and you |
62 | like joining a cult: After you joined, you are dependent on them and you |
53 | cannot use anything else, as it is simply incompatible to everything that |
63 | cannot use anything else, as they are simply incompatible to everything |
54 | isn't itself. What's worse, all the potential users of your module are |
64 | that isn't them. What's worse, all the potential users of your |
55 | I<also> forced to use the same event loop you use. |
65 | module are I<also> forced to use the same event loop you use. |
56 | |
66 | |
57 | AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works |
67 | AnyEvent is different: AnyEvent + POE works fine. AnyEvent + Glib works |
58 | fine. AnyEvent + Tk works fine etc. etc. but none of these work together |
68 | fine. AnyEvent + Tk works fine etc. etc. but none of these work together |
59 | with the rest: POE + IO::Async? No go. Tk + Event? No go. Again: if |
69 | with the rest: POE + IO::Async? No go. Tk + Event? No go. Again: if |
60 | your module uses one of those, every user of your module has to use it, |
70 | your module uses one of those, every user of your module has to use it, |
61 | too. But if your module uses AnyEvent, it works transparently with all |
71 | too. But if your module uses AnyEvent, it works transparently with all |
62 | event models it supports (including stuff like POE and IO::Async, as long |
72 | event models it supports (including stuff like IO::Async, as long as those |
63 | as those use one of the supported event loops. It is trivial to add new |
73 | use one of the supported event loops. It is trivial to add new event loops |
64 | event loops to AnyEvent, too, so it is future-proof). |
74 | to AnyEvent, too, so it is future-proof). |
65 | |
75 | |
66 | In addition to being free of having to use I<the one and only true event |
76 | In addition to being free of having to use I<the one and only true event |
67 | model>, AnyEvent also is free of bloat and policy: with POE or similar |
77 | model>, AnyEvent also is free of bloat and policy: with POE or similar |
68 | modules, you get an enormous amount of code and strict rules you have to |
78 | modules, you get an enormous amount of code and strict rules you have to |
69 | follow. AnyEvent, on the other hand, is lean and up to the point, by only |
79 | follow. AnyEvent, on the other hand, is lean and up to the point, by only |
… | |
… | |
127 | These watchers are normal Perl objects with normal Perl lifetime. After |
137 | These watchers are normal Perl objects with normal Perl lifetime. After |
128 | creating a watcher it will immediately "watch" for events and invoke the |
138 | creating a watcher it will immediately "watch" for events and invoke the |
129 | callback when the event occurs (of course, only when the event model |
139 | callback when the event occurs (of course, only when the event model |
130 | is in control). |
140 | is in control). |
131 | |
141 | |
|
|
142 | Note that B<callbacks must not permanently change global variables> |
|
|
143 | potentially in use by the event loop (such as C<$_> or C<$[>) and that B<< |
|
|
144 | callbacks must not C<die> >>. The former is good programming practise in |
|
|
145 | Perl and the latter stems from the fact that exception handling differs |
|
|
146 | widely between event loops. |
|
|
147 | |
132 | To disable the watcher you have to destroy it (e.g. by setting the |
148 | To disable the watcher you have to destroy it (e.g. by setting the |
133 | variable you store it in to C<undef> or otherwise deleting all references |
149 | variable you store it in to C<undef> or otherwise deleting all references |
134 | to it). |
150 | to it). |
135 | |
151 | |
136 | All watchers are created by calling a method on the C<AnyEvent> class. |
152 | All watchers are created by calling a method on the C<AnyEvent> class. |
… | |
… | |
330 | =head2 CHILD PROCESS WATCHERS |
346 | =head2 CHILD PROCESS WATCHERS |
331 | |
347 | |
332 | You can also watch on a child process exit and catch its exit status. |
348 | You can also watch on a child process exit and catch its exit status. |
333 | |
349 | |
334 | The child process is specified by the C<pid> argument (if set to C<0>, it |
350 | The child process is specified by the C<pid> argument (if set to C<0>, it |
335 | watches for any child process exit). The watcher will trigger as often |
351 | watches for any child process exit). The watcher will triggered only when |
336 | as status change for the child are received. This works by installing a |
352 | the child process has finished and an exit status is available, not on |
337 | signal handler for C<SIGCHLD>. The callback will be called with the pid |
353 | any trace events (stopped/continued). |
338 | and exit status (as returned by waitpid), so unlike other watcher types, |
354 | |
339 | you I<can> rely on child watcher callback arguments. |
355 | The callback will be called with the pid and exit status (as returned by |
|
|
356 | waitpid), so unlike other watcher types, you I<can> rely on child watcher |
|
|
357 | callback arguments. |
|
|
358 | |
|
|
359 | This watcher type works by installing a signal handler for C<SIGCHLD>, |
|
|
360 | and since it cannot be shared, nothing else should use SIGCHLD or reap |
|
|
361 | random child processes (waiting for specific child processes, e.g. inside |
|
|
362 | C<system>, is just fine). |
340 | |
363 | |
341 | There is a slight catch to child watchers, however: you usually start them |
364 | There is a slight catch to child watchers, however: you usually start them |
342 | I<after> the child process was created, and this means the process could |
365 | I<after> the child process was created, and this means the process could |
343 | have exited already (and no SIGCHLD will be sent anymore). |
366 | have exited already (and no SIGCHLD will be sent anymore). |
344 | |
367 | |
… | |
… | |
380 | The instrument to do that is called a "condition variable", so called |
403 | The instrument to do that is called a "condition variable", so called |
381 | because they represent a condition that must become true. |
404 | because they represent a condition that must become true. |
382 | |
405 | |
383 | Condition variables can be created by calling the C<< AnyEvent->condvar |
406 | Condition variables can be created by calling the C<< AnyEvent->condvar |
384 | >> method, usually without arguments. The only argument pair allowed is |
407 | >> method, usually without arguments. The only argument pair allowed is |
|
|
408 | |
385 | C<cb>, which specifies a callback to be called when the condition variable |
409 | C<cb>, which specifies a callback to be called when the condition variable |
386 | becomes true. |
410 | becomes true, with the condition variable as the first argument (but not |
|
|
411 | the results). |
387 | |
412 | |
388 | After creation, the condition variable is "false" until it becomes "true" |
413 | After creation, the condition variable is "false" until it becomes "true" |
389 | by calling the C<send> method (or calling the condition variable as if it |
414 | by calling the C<send> method (or calling the condition variable as if it |
390 | were a callback, read about the caveats in the description for the C<< |
415 | were a callback, read about the caveats in the description for the C<< |
391 | ->send >> method). |
416 | ->send >> method). |
… | |
… | |
447 | |
472 | |
448 | my $done = AnyEvent->condvar; |
473 | my $done = AnyEvent->condvar; |
449 | my $delay = AnyEvent->timer (after => 5, cb => $done); |
474 | my $delay = AnyEvent->timer (after => 5, cb => $done); |
450 | $done->recv; |
475 | $done->recv; |
451 | |
476 | |
|
|
477 | Example: Imagine an API that returns a condvar and doesn't support |
|
|
478 | callbacks. This is how you make a synchronous call, for example from |
|
|
479 | the main program: |
|
|
480 | |
|
|
481 | use AnyEvent::CouchDB; |
|
|
482 | |
|
|
483 | ... |
|
|
484 | |
|
|
485 | my @info = $couchdb->info->recv; |
|
|
486 | |
|
|
487 | And this is how you would just ste a callback to be called whenever the |
|
|
488 | results are available: |
|
|
489 | |
|
|
490 | $couchdb->info->cb (sub { |
|
|
491 | my @info = $_[0]->recv; |
|
|
492 | }); |
|
|
493 | |
452 | =head3 METHODS FOR PRODUCERS |
494 | =head3 METHODS FOR PRODUCERS |
453 | |
495 | |
454 | These methods should only be used by the producing side, i.e. the |
496 | These methods should only be used by the producing side, i.e. the |
455 | code/module that eventually sends the signal. Note that it is also |
497 | code/module that eventually sends the signal. Note that it is also |
456 | the producer side which creates the condvar in most cases, but it isn't |
498 | the producer side which creates the condvar in most cases, but it isn't |
… | |
… | |
589 | =item $bool = $cv->ready |
631 | =item $bool = $cv->ready |
590 | |
632 | |
591 | Returns true when the condition is "true", i.e. whether C<send> or |
633 | Returns true when the condition is "true", i.e. whether C<send> or |
592 | C<croak> have been called. |
634 | C<croak> have been called. |
593 | |
635 | |
594 | =item $cb = $cv->cb ([new callback]) |
636 | =item $cb = $cv->cb ($cb->($cv)) |
595 | |
637 | |
596 | This is a mutator function that returns the callback set and optionally |
638 | This is a mutator function that returns the callback set and optionally |
597 | replaces it before doing so. |
639 | replaces it before doing so. |
598 | |
640 | |
599 | The callback will be called when the condition becomes "true", i.e. when |
641 | The callback will be called when the condition becomes "true", i.e. when |
… | |
… | |
789 | =item L<AnyEvent::IGS> |
831 | =item L<AnyEvent::IGS> |
790 | |
832 | |
791 | A non-blocking interface to the Internet Go Server protocol (used by |
833 | A non-blocking interface to the Internet Go Server protocol (used by |
792 | L<App::IGS>). |
834 | L<App::IGS>). |
793 | |
835 | |
794 | =item L<Net::IRC3> |
836 | =item L<AnyEvent::IRC> |
795 | |
837 | |
796 | AnyEvent based IRC client module family. |
838 | AnyEvent based IRC client module family (replacing the older Net::IRC3). |
797 | |
839 | |
798 | =item L<Net::XMPP2> |
840 | =item L<Net::XMPP2> |
799 | |
841 | |
800 | AnyEvent based XMPP (Jabber protocol) module family. |
842 | AnyEvent based XMPP (Jabber protocol) module family. |
801 | |
843 | |
… | |
… | |
821 | =cut |
863 | =cut |
822 | |
864 | |
823 | package AnyEvent; |
865 | package AnyEvent; |
824 | |
866 | |
825 | no warnings; |
867 | no warnings; |
826 | use strict; |
868 | use strict qw(vars subs); |
827 | |
869 | |
828 | use Carp; |
870 | use Carp; |
829 | |
871 | |
830 | our $VERSION = 4.2; |
872 | our $VERSION = 4.341; |
831 | our $MODEL; |
873 | our $MODEL; |
832 | |
874 | |
833 | our $AUTOLOAD; |
875 | our $AUTOLOAD; |
834 | our @ISA; |
876 | our @ISA; |
835 | |
877 | |
… | |
… | |
940 | } |
982 | } |
941 | } |
983 | } |
942 | |
984 | |
943 | push @{"$MODEL\::ISA"}, "AnyEvent::Base"; |
985 | push @{"$MODEL\::ISA"}, "AnyEvent::Base"; |
944 | |
986 | |
945 | if ($ENV{PERL_ANYEVENT_STRICT}) { |
|
|
946 | unshift @AnyEvent::Base::Strict::ISA, $MODEL; |
|
|
947 | unshift @ISA, AnyEvent::Base::Strict:: |
|
|
948 | } else { |
|
|
949 | unshift @ISA, $MODEL; |
987 | unshift @ISA, $MODEL; |
950 | } |
988 | |
|
|
989 | require AnyEvent::Strict if $ENV{PERL_ANYEVENT_STRICT}; |
951 | |
990 | |
952 | (shift @post_detect)->() while @post_detect; |
991 | (shift @post_detect)->() while @post_detect; |
953 | } |
992 | } |
954 | |
993 | |
955 | $MODEL |
994 | $MODEL |
… | |
… | |
965 | |
1004 | |
966 | my $class = shift; |
1005 | my $class = shift; |
967 | $class->$func (@_); |
1006 | $class->$func (@_); |
968 | } |
1007 | } |
969 | |
1008 | |
|
|
1009 | # utility function to dup a filehandle. this is used by many backends |
|
|
1010 | # to support binding more than one watcher per filehandle (they usually |
|
|
1011 | # allow only one watcher per fd, so we dup it to get a different one). |
|
|
1012 | sub _dupfh($$$$) { |
|
|
1013 | my ($poll, $fh, $r, $w) = @_; |
|
|
1014 | |
|
|
1015 | # cygwin requires the fh mode to be matching, unix doesn't |
|
|
1016 | my ($rw, $mode) = $poll eq "r" ? ($r, "<") |
|
|
1017 | : $poll eq "w" ? ($w, ">") |
|
|
1018 | : Carp::croak "AnyEvent->io requires poll set to either 'r' or 'w'"; |
|
|
1019 | |
|
|
1020 | open my $fh2, "$mode&" . fileno $fh |
|
|
1021 | or die "cannot dup() filehandle: $!"; |
|
|
1022 | |
|
|
1023 | # we assume CLOEXEC is already set by perl in all important cases |
|
|
1024 | |
|
|
1025 | ($fh2, $rw) |
|
|
1026 | } |
|
|
1027 | |
970 | package AnyEvent::Base; |
1028 | package AnyEvent::Base; |
971 | |
1029 | |
972 | # default implementation for now and time |
1030 | # default implementation for now and time |
973 | |
1031 | |
974 | use Time::HiRes (); |
1032 | BEGIN { |
|
|
1033 | if (eval "use Time::HiRes (); time (); 1") { |
|
|
1034 | *_time = \&Time::HiRes::time; |
|
|
1035 | # if (eval "use POSIX (); (POSIX::times())... |
|
|
1036 | } else { |
|
|
1037 | *_time = sub { time }; # epic fail |
|
|
1038 | } |
|
|
1039 | } |
975 | |
1040 | |
976 | sub time { Time::HiRes::time } |
1041 | sub time { _time } |
977 | sub now { Time::HiRes::time } |
1042 | sub now { _time } |
978 | |
1043 | |
979 | # default implementation for ->condvar |
1044 | # default implementation for ->condvar |
980 | |
1045 | |
981 | sub condvar { |
1046 | sub condvar { |
982 | bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, AnyEvent::CondVar:: |
1047 | bless { @_ == 3 ? (_ae_cb => $_[2]) : () }, AnyEvent::CondVar:: |
983 | } |
1048 | } |
984 | |
1049 | |
985 | # default implementation for ->signal |
1050 | # default implementation for ->signal |
986 | |
1051 | |
987 | our %SIG_CB; |
1052 | our ($SIGPIPE_R, $SIGPIPE_W, %SIG_CB, %SIG_EV, $SIG_IO); |
|
|
1053 | |
|
|
1054 | sub _signal_exec { |
|
|
1055 | sysread $SIGPIPE_R, my $dummy, 4; |
|
|
1056 | |
|
|
1057 | while (%SIG_EV) { |
|
|
1058 | for (keys %SIG_EV) { |
|
|
1059 | delete $SIG_EV{$_}; |
|
|
1060 | $_->() for values %{ $SIG_CB{$_} || {} }; |
|
|
1061 | } |
|
|
1062 | } |
|
|
1063 | } |
988 | |
1064 | |
989 | sub signal { |
1065 | sub signal { |
990 | my (undef, %arg) = @_; |
1066 | my (undef, %arg) = @_; |
991 | |
1067 | |
|
|
1068 | unless ($SIGPIPE_R) { |
|
|
1069 | if (AnyEvent::WIN32) { |
|
|
1070 | ($SIGPIPE_R, $SIGPIPE_W) = AnyEvent::Util::portable_pipe (); |
|
|
1071 | AnyEvent::Util::fh_nonblocking ($SIGPIPE_R) if $SIGPIPE_R; |
|
|
1072 | AnyEvent::Util::fh_nonblocking ($SIGPIPE_W) if $SIGPIPE_W; # just in case |
|
|
1073 | } else { |
|
|
1074 | pipe $SIGPIPE_R, $SIGPIPE_W; |
|
|
1075 | require Fcntl; |
|
|
1076 | fcntl $SIGPIPE_R, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_R; |
|
|
1077 | fcntl $SIGPIPE_W, &Fcntl::F_SETFL, &Fcntl::O_NONBLOCK if $SIGPIPE_W; # just in case |
|
|
1078 | } |
|
|
1079 | |
|
|
1080 | $SIGPIPE_R |
|
|
1081 | or Carp::croak "AnyEvent: unable to create a signal reporting pipe: $!\n"; |
|
|
1082 | |
|
|
1083 | $SIG_IO = AnyEvent->io (fh => $SIGPIPE_R, poll => "r", cb => \&_signal_exec); |
|
|
1084 | } |
|
|
1085 | |
992 | my $signal = uc $arg{signal} |
1086 | my $signal = uc $arg{signal} |
993 | or Carp::croak "required option 'signal' is missing"; |
1087 | or Carp::croak "required option 'signal' is missing"; |
994 | |
1088 | |
995 | $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; |
1089 | $SIG_CB{$signal}{$arg{cb}} = $arg{cb}; |
996 | $SIG{$signal} ||= sub { |
1090 | $SIG{$signal} ||= sub { |
997 | $_->() for values %{ $SIG_CB{$signal} || {} }; |
1091 | syswrite $SIGPIPE_W, "\x00", 1 unless %SIG_EV; |
|
|
1092 | undef $SIG_EV{$signal}; |
998 | }; |
1093 | }; |
999 | |
1094 | |
1000 | bless [$signal, $arg{cb}], "AnyEvent::Base::Signal" |
1095 | bless [$signal, $arg{cb}], "AnyEvent::Base::Signal" |
1001 | } |
1096 | } |
1002 | |
1097 | |
… | |
… | |
1121 | |
1216 | |
1122 | # undocumented/compatibility with pre-3.4 |
1217 | # undocumented/compatibility with pre-3.4 |
1123 | *broadcast = \&send; |
1218 | *broadcast = \&send; |
1124 | *wait = \&_wait; |
1219 | *wait = \&_wait; |
1125 | |
1220 | |
1126 | package AnyEvent::Base::Strict; |
1221 | =head1 ERROR AND EXCEPTION HANDLING |
1127 | |
1222 | |
1128 | use Carp qw(croak); |
1223 | In general, AnyEvent does not do any error handling - it relies on the |
|
|
1224 | caller to do that if required. The L<AnyEvent::Strict> module (see also |
|
|
1225 | the C<PERL_ANYEVENT_STRICT> environment variable, below) provides strict |
|
|
1226 | checking of all AnyEvent methods, however, which is highly useful during |
|
|
1227 | development. |
1129 | |
1228 | |
1130 | # supply checks for argument validity for many functions |
1229 | As for exception handling (i.e. runtime errors and exceptions thrown while |
|
|
1230 | executing a callback), this is not only highly event-loop specific, but |
|
|
1231 | also not in any way wrapped by this module, as this is the job of the main |
|
|
1232 | program. |
1131 | |
1233 | |
1132 | sub io { |
1234 | The pure perl event loop simply re-throws the exception (usually |
1133 | my $class = shift; |
1235 | within C<< condvar->recv >>), the L<Event> and L<EV> modules call C<< |
1134 | my %arg = @_; |
1236 | $Event/EV::DIED->() >>, L<Glib> uses C<< install_exception_handler >> and |
|
|
1237 | so on. |
1135 | |
1238 | |
1136 | ref $arg{cb} |
1239 | =head1 ENVIRONMENT VARIABLES |
1137 | or croak "AnyEvent->io called with illegal cb argument '$arg{cb}'"; |
|
|
1138 | delete $arg{cb}; |
|
|
1139 | |
|
|
1140 | fileno $arg{fh} |
|
|
1141 | or croak "AnyEvent->io called with illegal fh argument '$arg{fh}'"; |
|
|
1142 | delete $arg{fh}; |
|
|
1143 | |
|
|
1144 | $arg{poll} =~ /^[rw]$/ |
|
|
1145 | or croak "AnyEvent->io called with illegal poll argument '$arg{poll}'"; |
|
|
1146 | delete $arg{poll}; |
|
|
1147 | |
|
|
1148 | croak "AnyEvent->io called with unsupported parameter(s) " . join ", ", keys %arg |
|
|
1149 | if keys %arg; |
|
|
1150 | |
1240 | |
1151 | $class->SUPER::io (@_) |
1241 | The following environment variables are used by this module or its |
1152 | } |
1242 | submodules: |
1153 | |
1243 | |
1154 | sub timer { |
1244 | =over 4 |
1155 | my $class = shift; |
|
|
1156 | my %arg = @_; |
|
|
1157 | |
1245 | |
1158 | ref $arg{cb} |
1246 | =item C<PERL_ANYEVENT_VERBOSE> |
1159 | or croak "AnyEvent->timer called with illegal cb argument '$arg{cb}'"; |
|
|
1160 | delete $arg{cb}; |
|
|
1161 | |
|
|
1162 | exists $arg{after} |
|
|
1163 | or croak "AnyEvent->timer called without mandatory 'after' parameter"; |
|
|
1164 | delete $arg{after}; |
|
|
1165 | |
|
|
1166 | $arg{interval} > 0 || !$arg{interval} |
|
|
1167 | or croak "AnyEvent->timer called with illegal interval argument '$arg{interval}'"; |
|
|
1168 | delete $arg{interval}; |
|
|
1169 | |
|
|
1170 | croak "AnyEvent->timer called with unsupported parameter(s) " . join ", ", keys %arg |
|
|
1171 | if keys %arg; |
|
|
1172 | |
1247 | |
1173 | $class->SUPER::timer (@_) |
1248 | By default, AnyEvent will be completely silent except in fatal |
1174 | } |
1249 | conditions. You can set this environment variable to make AnyEvent more |
|
|
1250 | talkative. |
1175 | |
1251 | |
1176 | sub signal { |
1252 | When set to C<1> or higher, causes AnyEvent to warn about unexpected |
1177 | my $class = shift; |
1253 | conditions, such as not being able to load the event model specified by |
1178 | my %arg = @_; |
1254 | C<PERL_ANYEVENT_MODEL>. |
1179 | |
1255 | |
1180 | ref $arg{cb} |
1256 | When set to C<2> or higher, cause AnyEvent to report to STDERR which event |
1181 | or croak "AnyEvent->signal called with illegal cb argument '$arg{cb}'"; |
1257 | model it chooses. |
1182 | delete $arg{cb}; |
|
|
1183 | |
|
|
1184 | eval "require POSIX; defined &POSIX::SIG$arg{signal}" |
|
|
1185 | or croak "AnyEvent->signal called with illegal signal name '$arg{signal}'"; |
|
|
1186 | delete $arg{signal}; |
|
|
1187 | |
|
|
1188 | croak "AnyEvent->signal called with unsupported parameter(s) " . join ", ", keys %arg |
|
|
1189 | if keys %arg; |
|
|
1190 | |
1258 | |
1191 | $class->SUPER::signal (@_) |
1259 | =item C<PERL_ANYEVENT_STRICT> |
1192 | } |
|
|
1193 | |
1260 | |
1194 | sub child { |
1261 | AnyEvent does not do much argument checking by default, as thorough |
1195 | my $class = shift; |
1262 | argument checking is very costly. Setting this variable to a true value |
1196 | my %arg = @_; |
1263 | will cause AnyEvent to load C<AnyEvent::Strict> and then to thoroughly |
|
|
1264 | check the arguments passed to most method calls. If it finds any problems |
|
|
1265 | it will croak. |
1197 | |
1266 | |
1198 | ref $arg{cb} |
1267 | In other words, enables "strict" mode. |
1199 | or croak "AnyEvent->signal called with illegal cb argument '$arg{cb}'"; |
|
|
1200 | delete $arg{cb}; |
|
|
1201 | |
|
|
1202 | $arg{pid} =~ /^-?\d+$/ |
|
|
1203 | or croak "AnyEvent->signal called with illegal pid value '$arg{pid}'"; |
|
|
1204 | delete $arg{pid}; |
|
|
1205 | |
|
|
1206 | croak "AnyEvent->signal called with unsupported parameter(s) " . join ", ", keys %arg |
|
|
1207 | if keys %arg; |
|
|
1208 | |
1268 | |
1209 | $class->SUPER::child (@_) |
1269 | Unlike C<use strict>, it is definitely recommended ot keep it off in |
1210 | } |
1270 | production. Keeping C<PERL_ANYEVENT_STRICT=1> in your environment while |
|
|
1271 | developing programs can be very useful, however. |
1211 | |
1272 | |
1212 | sub condvar { |
1273 | =item C<PERL_ANYEVENT_MODEL> |
1213 | my $class = shift; |
|
|
1214 | my %arg = @_; |
|
|
1215 | |
1274 | |
1216 | !exists $arg{cb} or ref $arg{cb} |
1275 | This can be used to specify the event model to be used by AnyEvent, before |
1217 | or croak "AnyEvent->condvar called with illegal cb argument '$arg{cb}'"; |
1276 | auto detection and -probing kicks in. It must be a string consisting |
1218 | delete $arg{cb}; |
1277 | entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended |
1219 | |
1278 | and the resulting module name is loaded and if the load was successful, |
1220 | croak "AnyEvent->condvar called with unsupported parameter(s) " . join ", ", keys %arg |
1279 | used as event model. If it fails to load AnyEvent will proceed with |
1221 | if keys %arg; |
1280 | auto detection and -probing. |
1222 | |
1281 | |
1223 | $class->SUPER::condvar (@_) |
1282 | This functionality might change in future versions. |
1224 | } |
|
|
1225 | |
1283 | |
1226 | sub time { |
1284 | For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you |
1227 | my $class = shift; |
1285 | could start your program like this: |
1228 | |
1286 | |
1229 | @_ |
1287 | PERL_ANYEVENT_MODEL=Perl perl ... |
1230 | and croak "AnyEvent->time wrongly called with paramaters"; |
|
|
1231 | |
1288 | |
1232 | $class->SUPER::time (@_) |
1289 | =item C<PERL_ANYEVENT_PROTOCOLS> |
1233 | } |
|
|
1234 | |
1290 | |
1235 | sub now { |
1291 | Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences |
1236 | my $class = shift; |
1292 | for IPv4 or IPv6. The default is unspecified (and might change, or be the result |
|
|
1293 | of auto probing). |
1237 | |
1294 | |
1238 | @_ |
1295 | Must be set to a comma-separated list of protocols or address families, |
1239 | and croak "AnyEvent->now wrongly called with paramaters"; |
1296 | current supported: C<ipv4> and C<ipv6>. Only protocols mentioned will be |
|
|
1297 | used, and preference will be given to protocols mentioned earlier in the |
|
|
1298 | list. |
1240 | |
1299 | |
1241 | $class->SUPER::now (@_) |
1300 | This variable can effectively be used for denial-of-service attacks |
1242 | } |
1301 | against local programs (e.g. when setuid), although the impact is likely |
|
|
1302 | small, as the program has to handle conenction and other failures anyways. |
|
|
1303 | |
|
|
1304 | Examples: C<PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6> - prefer IPv4 over IPv6, |
|
|
1305 | but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4> |
|
|
1306 | - only support IPv4, never try to resolve or contact IPv6 |
|
|
1307 | addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or |
|
|
1308 | IPv6, but prefer IPv6 over IPv4. |
|
|
1309 | |
|
|
1310 | =item C<PERL_ANYEVENT_EDNS0> |
|
|
1311 | |
|
|
1312 | Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension |
|
|
1313 | for DNS. This extension is generally useful to reduce DNS traffic, but |
|
|
1314 | some (broken) firewalls drop such DNS packets, which is why it is off by |
|
|
1315 | default. |
|
|
1316 | |
|
|
1317 | Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce |
|
|
1318 | EDNS0 in its DNS requests. |
|
|
1319 | |
|
|
1320 | =item C<PERL_ANYEVENT_MAX_FORKS> |
|
|
1321 | |
|
|
1322 | The maximum number of child processes that C<AnyEvent::Util::fork_call> |
|
|
1323 | will create in parallel. |
|
|
1324 | |
|
|
1325 | =back |
1243 | |
1326 | |
1244 | =head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE |
1327 | =head1 SUPPLYING YOUR OWN EVENT MODEL INTERFACE |
1245 | |
1328 | |
1246 | This is an advanced topic that you do not normally need to use AnyEvent in |
1329 | This is an advanced topic that you do not normally need to use AnyEvent in |
1247 | a module. This section is only of use to event loop authors who want to |
1330 | a module. This section is only of use to event loop authors who want to |
… | |
… | |
1281 | |
1364 | |
1282 | I<rxvt-unicode> also cheats a bit by not providing blocking access to |
1365 | I<rxvt-unicode> also cheats a bit by not providing blocking access to |
1283 | condition variables: code blocking while waiting for a condition will |
1366 | condition variables: code blocking while waiting for a condition will |
1284 | C<die>. This still works with most modules/usages, and blocking calls must |
1367 | C<die>. This still works with most modules/usages, and blocking calls must |
1285 | not be done in an interactive application, so it makes sense. |
1368 | not be done in an interactive application, so it makes sense. |
1286 | |
|
|
1287 | =head1 ENVIRONMENT VARIABLES |
|
|
1288 | |
|
|
1289 | The following environment variables are used by this module: |
|
|
1290 | |
|
|
1291 | =over 4 |
|
|
1292 | |
|
|
1293 | =item C<PERL_ANYEVENT_VERBOSE> |
|
|
1294 | |
|
|
1295 | By default, AnyEvent will be completely silent except in fatal |
|
|
1296 | conditions. You can set this environment variable to make AnyEvent more |
|
|
1297 | talkative. |
|
|
1298 | |
|
|
1299 | When set to C<1> or higher, causes AnyEvent to warn about unexpected |
|
|
1300 | conditions, such as not being able to load the event model specified by |
|
|
1301 | C<PERL_ANYEVENT_MODEL>. |
|
|
1302 | |
|
|
1303 | When set to C<2> or higher, cause AnyEvent to report to STDERR which event |
|
|
1304 | model it chooses. |
|
|
1305 | |
|
|
1306 | =item C<PERL_ANYEVENT_STRICT> |
|
|
1307 | |
|
|
1308 | AnyEvent does not do much argument checking by default, as thorough |
|
|
1309 | argument checking is very costly. Setting this variable to a true value |
|
|
1310 | will cause AnyEvent to thoroughly check the arguments passed to most |
|
|
1311 | method calls and croaks if it finds any problems. In other words, enables |
|
|
1312 | "strict" mode. Unlike C<use strict> it is definitely recommended ot keep |
|
|
1313 | it off in production. |
|
|
1314 | |
|
|
1315 | =item C<PERL_ANYEVENT_MODEL> |
|
|
1316 | |
|
|
1317 | This can be used to specify the event model to be used by AnyEvent, before |
|
|
1318 | auto detection and -probing kicks in. It must be a string consisting |
|
|
1319 | entirely of ASCII letters. The string C<AnyEvent::Impl::> gets prepended |
|
|
1320 | and the resulting module name is loaded and if the load was successful, |
|
|
1321 | used as event model. If it fails to load AnyEvent will proceed with |
|
|
1322 | auto detection and -probing. |
|
|
1323 | |
|
|
1324 | This functionality might change in future versions. |
|
|
1325 | |
|
|
1326 | For example, to force the pure perl model (L<AnyEvent::Impl::Perl>) you |
|
|
1327 | could start your program like this: |
|
|
1328 | |
|
|
1329 | PERL_ANYEVENT_MODEL=Perl perl ... |
|
|
1330 | |
|
|
1331 | =item C<PERL_ANYEVENT_PROTOCOLS> |
|
|
1332 | |
|
|
1333 | Used by both L<AnyEvent::DNS> and L<AnyEvent::Socket> to determine preferences |
|
|
1334 | for IPv4 or IPv6. The default is unspecified (and might change, or be the result |
|
|
1335 | of auto probing). |
|
|
1336 | |
|
|
1337 | Must be set to a comma-separated list of protocols or address families, |
|
|
1338 | current supported: C<ipv4> and C<ipv6>. Only protocols mentioned will be |
|
|
1339 | used, and preference will be given to protocols mentioned earlier in the |
|
|
1340 | list. |
|
|
1341 | |
|
|
1342 | This variable can effectively be used for denial-of-service attacks |
|
|
1343 | against local programs (e.g. when setuid), although the impact is likely |
|
|
1344 | small, as the program has to handle connection errors already- |
|
|
1345 | |
|
|
1346 | Examples: C<PERL_ANYEVENT_PROTOCOLS=ipv4,ipv6> - prefer IPv4 over IPv6, |
|
|
1347 | but support both and try to use both. C<PERL_ANYEVENT_PROTOCOLS=ipv4> |
|
|
1348 | - only support IPv4, never try to resolve or contact IPv6 |
|
|
1349 | addresses. C<PERL_ANYEVENT_PROTOCOLS=ipv6,ipv4> support either IPv4 or |
|
|
1350 | IPv6, but prefer IPv6 over IPv4. |
|
|
1351 | |
|
|
1352 | =item C<PERL_ANYEVENT_EDNS0> |
|
|
1353 | |
|
|
1354 | Used by L<AnyEvent::DNS> to decide whether to use the EDNS0 extension |
|
|
1355 | for DNS. This extension is generally useful to reduce DNS traffic, but |
|
|
1356 | some (broken) firewalls drop such DNS packets, which is why it is off by |
|
|
1357 | default. |
|
|
1358 | |
|
|
1359 | Setting this variable to C<1> will cause L<AnyEvent::DNS> to announce |
|
|
1360 | EDNS0 in its DNS requests. |
|
|
1361 | |
|
|
1362 | =item C<PERL_ANYEVENT_MAX_FORKS> |
|
|
1363 | |
|
|
1364 | The maximum number of child processes that C<AnyEvent::Util::fork_call> |
|
|
1365 | will create in parallel. |
|
|
1366 | |
|
|
1367 | =back |
|
|
1368 | |
1369 | |
1369 | =head1 EXAMPLE PROGRAM |
1370 | =head1 EXAMPLE PROGRAM |
1370 | |
1371 | |
1371 | The following program uses an I/O watcher to read data from STDIN, a timer |
1372 | The following program uses an I/O watcher to read data from STDIN, a timer |
1372 | to display a message once per second, and a condition variable to quit the |
1373 | to display a message once per second, and a condition variable to quit the |
… | |
… | |
1566 | watcher. |
1567 | watcher. |
1567 | |
1568 | |
1568 | =head3 Results |
1569 | =head3 Results |
1569 | |
1570 | |
1570 | name watchers bytes create invoke destroy comment |
1571 | name watchers bytes create invoke destroy comment |
1571 | EV/EV 400000 244 0.56 0.46 0.31 EV native interface |
1572 | EV/EV 400000 224 0.47 0.35 0.27 EV native interface |
1572 | EV/Any 100000 244 2.50 0.46 0.29 EV + AnyEvent watchers |
1573 | EV/Any 100000 224 2.88 0.34 0.27 EV + AnyEvent watchers |
1573 | CoroEV/Any 100000 244 2.49 0.44 0.29 coroutines + Coro::Signal |
1574 | CoroEV/Any 100000 224 2.85 0.35 0.28 coroutines + Coro::Signal |
1574 | Perl/Any 100000 513 4.92 0.87 1.12 pure perl implementation |
1575 | Perl/Any 100000 452 4.13 0.73 0.95 pure perl implementation |
1575 | Event/Event 16000 516 31.88 31.30 0.85 Event native interface |
1576 | Event/Event 16000 517 32.20 31.80 0.81 Event native interface |
1576 | Event/Any 16000 590 35.75 31.42 1.08 Event + AnyEvent watchers |
1577 | Event/Any 16000 590 35.85 31.55 1.06 Event + AnyEvent watchers |
1577 | Glib/Any 16000 1357 98.22 12.41 54.00 quadratic behaviour |
1578 | Glib/Any 16000 1357 102.33 12.31 51.00 quadratic behaviour |
1578 | Tk/Any 2000 1860 26.97 67.98 14.00 SEGV with >> 2000 watchers |
1579 | Tk/Any 2000 1860 27.20 66.31 14.00 SEGV with >> 2000 watchers |
1579 | POE/Event 2000 6644 108.64 736.02 14.73 via POE::Loop::Event |
1580 | POE/Event 2000 6328 109.99 751.67 14.02 via POE::Loop::Event |
1580 | POE/Select 2000 6343 94.13 809.12 565.96 via POE::Loop::Select |
1581 | POE/Select 2000 6027 94.54 809.13 579.80 via POE::Loop::Select |
1581 | |
1582 | |
1582 | =head3 Discussion |
1583 | =head3 Discussion |
1583 | |
1584 | |
1584 | The benchmark does I<not> measure scalability of the event loop very |
1585 | The benchmark does I<not> measure scalability of the event loop very |
1585 | well. For example, a select-based event loop (such as the pure perl one) |
1586 | well. For example, a select-based event loop (such as the pure perl one) |
… | |
… | |
1787 | watchers, as the management overhead dominates. |
1788 | watchers, as the management overhead dominates. |
1788 | |
1789 | |
1789 | =back |
1790 | =back |
1790 | |
1791 | |
1791 | |
1792 | |
|
|
1793 | =head1 SIGNALS |
|
|
1794 | |
|
|
1795 | AnyEvent currently installs handlers for these signals: |
|
|
1796 | |
|
|
1797 | =over 4 |
|
|
1798 | |
|
|
1799 | =item SIGCHLD |
|
|
1800 | |
|
|
1801 | A handler for C<SIGCHLD> is installed by AnyEvent's child watcher |
|
|
1802 | emulation for event loops that do not support them natively. Also, some |
|
|
1803 | event loops install a similar handler. |
|
|
1804 | |
|
|
1805 | =item SIGPIPE |
|
|
1806 | |
|
|
1807 | A no-op handler is installed for C<SIGPIPE> when C<$SIG{PIPE}> is C<undef> |
|
|
1808 | when AnyEvent gets loaded. |
|
|
1809 | |
|
|
1810 | The rationale for this is that AnyEvent users usually do not really depend |
|
|
1811 | on SIGPIPE delivery (which is purely an optimisation for shell use, or |
|
|
1812 | badly-written programs), but C<SIGPIPE> can cause spurious and rare |
|
|
1813 | program exits as a lot of people do not expect C<SIGPIPE> when writing to |
|
|
1814 | some random socket. |
|
|
1815 | |
|
|
1816 | The rationale for installing a no-op handler as opposed to ignoring it is |
|
|
1817 | that this way, the handler will be restored to defaults on exec. |
|
|
1818 | |
|
|
1819 | Feel free to install your own handler, or reset it to defaults. |
|
|
1820 | |
|
|
1821 | =back |
|
|
1822 | |
|
|
1823 | =cut |
|
|
1824 | |
|
|
1825 | $SIG{PIPE} = sub { } |
|
|
1826 | unless defined $SIG{PIPE}; |
|
|
1827 | |
|
|
1828 | |
1792 | =head1 FORK |
1829 | =head1 FORK |
1793 | |
1830 | |
1794 | Most event libraries are not fork-safe. The ones who are usually are |
1831 | Most event libraries are not fork-safe. The ones who are usually are |
1795 | because they rely on inefficient but fork-safe C<select> or C<poll> |
1832 | because they rely on inefficient but fork-safe C<select> or C<poll> |
1796 | calls. Only L<EV> is fully fork-aware. |
1833 | calls. Only L<EV> is fully fork-aware. |
… | |
… | |
1824 | =head1 BUGS |
1861 | =head1 BUGS |
1825 | |
1862 | |
1826 | Perl 5.8 has numerous memleaks that sometimes hit this module and are hard |
1863 | Perl 5.8 has numerous memleaks that sometimes hit this module and are hard |
1827 | to work around. If you suffer from memleaks, first upgrade to Perl 5.10 |
1864 | to work around. If you suffer from memleaks, first upgrade to Perl 5.10 |
1828 | and check wether the leaks still show up. (Perl 5.10.0 has other annoying |
1865 | and check wether the leaks still show up. (Perl 5.10.0 has other annoying |
1829 | mamleaks, such as leaking on C<map> and C<grep> but it is usually not as |
1866 | memleaks, such as leaking on C<map> and C<grep> but it is usually not as |
1830 | pronounced). |
1867 | pronounced). |
1831 | |
1868 | |
1832 | |
1869 | |
1833 | =head1 SEE ALSO |
1870 | =head1 SEE ALSO |
1834 | |
1871 | |