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Revision 1.83 by root, Mon Jan 28 12:24:05 2008 UTC vs.
Revision 1.99 by root, Tue Jul 8 09:37:37 2008 UTC

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2 2
3EV - perl interface to libev, a high performance full-featured event loop 3EV - perl interface to libev, a high performance full-featured event loop
4 4
5=head1 SYNOPSIS 5=head1 SYNOPSIS
6 6
7 use EV; 7 use EV;
8
9 # TIMERS
10
11 my $w = EV::timer 2, 0, sub {
12 warn "is called after 2s";
13 };
14
15 my $w = EV::timer 2, 2, sub {
16 warn "is called roughly every 2s (repeat = 2)";
17 };
18
19 undef $w; # destroy event watcher again
20
21 my $w = EV::periodic 0, 60, 0, sub {
22 warn "is called every minute, on the minute, exactly";
23 };
24
25 # IO
26
27 my $w = EV::io *STDIN, EV::READ, sub {
28 my ($w, $revents) = @_; # all callbacks receive the watcher and event mask
29 warn "stdin is readable, you entered: ", <STDIN>;
30 };
31
32 # SIGNALS
33
34 my $w = EV::signal 'QUIT', sub {
35 warn "sigquit received\n";
36 };
37
38 # CHILD/PID STATUS CHANGES
8 39
9 # TIMERS 40 my $w = EV::child 666, 0, sub {
41 my ($w, $revents) = @_;
42 my $status = $w->rstatus;
43 };
10 44
11 my $w = EV::timer 2, 0, sub {
12 warn "is called after 2s";
13 };
14
15 my $w = EV::timer 2, 2, sub {
16 warn "is called roughly every 2s (repeat = 2)";
17 };
18
19 undef $w; # destroy event watcher again
20
21 my $w = EV::periodic 0, 60, 0, sub {
22 warn "is called every minute, on the minute, exactly";
23 };
24
25 # IO
26
27 my $w = EV::io *STDIN, EV::READ, sub {
28 my ($w, $revents) = @_; # all callbacks receive the watcher and event mask
29 warn "stdin is readable, you entered: ", <STDIN>;
30 };
31
32 # SIGNALS
33
34 my $w = EV::signal 'QUIT', sub {
35 warn "sigquit received\n";
36 };
37
38 # CHILD/PID STATUS CHANGES
39
40 my $w = EV::child 666, 0, sub {
41 my ($w, $revents) = @_;
42 my $status = $w->rstatus;
43 };
44
45 # STAT CHANGES 45 # STAT CHANGES
46 my $w = EV::stat "/etc/passwd", 10, sub { 46 my $w = EV::stat "/etc/passwd", 10, sub {
47 my ($w, $revents) = @_; 47 my ($w, $revents) = @_;
48 warn $w->path, " has changed somehow.\n"; 48 warn $w->path, " has changed somehow.\n";
49 }; 49 };
50 50
51 # MAINLOOP 51 # MAINLOOP
52 EV::loop; # loop until EV::unloop is called or all watchers stop 52 EV::loop; # loop until EV::unloop is called or all watchers stop
53 EV::loop EV::LOOP_ONESHOT; # block until at least one event could be handled 53 EV::loop EV::LOOP_ONESHOT; # block until at least one event could be handled
54 EV::loop EV::LOOP_NONBLOCK; # try to handle same events, but do not block 54 EV::loop EV::LOOP_NONBLOCK; # try to handle same events, but do not block
55 55
56=head1 DESCRIPTION 56=head1 DESCRIPTION
57 57
58This module provides an interface to libev 58This module provides an interface to libev
59(L<http://software.schmorp.de/pkg/libev.html>). While the documentation 59(L<http://software.schmorp.de/pkg/libev.html>). While the documentation
60below is comprehensive, one might also consult the documentation of libev 60below is comprehensive, one might also consult the documentation of libev
61itself (L<http://cvs.schmorp.de/libev/ev.html>) for more subtle details on 61itself (L<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod>) for more
62watcher semantics or some discussion on the available backends, or how to 62subtle details on watcher semantics or some discussion on the available
63force a specific backend with C<LIBEV_FLAGS>, or just about in any case 63backends, or how to force a specific backend with C<LIBEV_FLAGS>, or just
64because it has much more detailed information. 64about in any case because it has much more detailed information.
65
66This module is very fast and scalable. It is actually so fast that you
67can use it through the L<AnyEvent> module, stay portable to other event
68loops (if you don't rely on any watcher types not available through it)
69and still be faster than with any other event loop currently supported in
70Perl.
65 71
66=cut 72=cut
67 73
68package EV; 74package EV;
69 75
70use strict; 76use strict;
71 77
72BEGIN { 78BEGIN {
73 our $VERSION = '3.0'; 79 our $VERSION = '3.42';
74 use XSLoader; 80 use XSLoader;
75 XSLoader::load "EV", $VERSION; 81 XSLoader::load "EV", $VERSION;
76} 82}
77 83
78@EV::IO::ISA = 84@EV::IO::ISA =
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84@EV::Idle::ISA = 90@EV::Idle::ISA =
85@EV::Prepare::ISA = 91@EV::Prepare::ISA =
86@EV::Check::ISA = 92@EV::Check::ISA =
87@EV::Embed::ISA = 93@EV::Embed::ISA =
88@EV::Fork::ISA = 94@EV::Fork::ISA =
95@EV::Async::ISA =
89 "EV::Watcher"; 96 "EV::Watcher";
90 97
91@EV::Loop::Default::ISA = "EV::Loop"; 98@EV::Loop::Default::ISA = "EV::Loop";
92 99
93=head1 EVENT LOOPS 100=head1 EVENT LOOPS
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104default loop as this is fastest (perl-wise), best supported by other 111default loop as this is fastest (perl-wise), best supported by other
105modules (e.g. AnyEvent or Coro) and most portable event loop. 112modules (e.g. AnyEvent or Coro) and most portable event loop.
106 113
107For specific programs you can create additional event loops dynamically. 114For specific programs you can create additional event loops dynamically.
108 115
116If you want to take avdantage of kqueue (which often works properly for
117sockets only) even though the default loop doesn't enable it, you can
118I<embed> a kqueue loop into the default loop: running the default loop
119will then also service the kqueue loop to some extent. See the example in
120the section about embed watchers for an example on how to achieve that.
121
109=over 4 122=over 4
110 123
111=item $loop = new EV::loop [$flags] 124=item $loop = new EV::loop [$flags]
112 125
113Create a new event loop as per the specified flags. Please refer to the 126Create a new event loop as per the specified flags. Please refer to the
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123 136
124=item $loop->loop_fork 137=item $loop->loop_fork
125 138
126Must be called after a fork in the child, before entering or continuing 139Must be called after a fork in the child, before entering or continuing
127the event loop. An alternative is to use C<EV::FLAG_FORKCHECK> which calls 140the event loop. An alternative is to use C<EV::FLAG_FORKCHECK> which calls
128this fucntion automatically, at some performance loss (refer to the libev 141this function automatically, at some performance loss (refer to the libev
129documentation). 142documentation).
130 143
144=item $loop->loop_verify
145
146Calls C<ev_verify> to make internal consistency checks (for debugging
147libev) and abort the program if any data structures were found to be
148corrupted.
149
131=item $loop = EV::default_loop [$flags] 150=item $loop = EV::default_loop [$flags]
132 151
133Return the default loop (which is a singleton object). 152Return the default loop (which is a singleton object). Since this module
153already creates the default loop with default flags, specifying flags here
154will not have any effect unless you destroy the default loop first, which
155isn't supported. So in short: don't do it, and if you break it, you get to
156keep the pieces.
134 157
135=back 158=back
136 159
137 160
138=head1 BASIC INTERFACE 161=head1 BASIC INTERFACE
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268 291
269A watcher is an object that gets created to record your interest in some 292A watcher is an object that gets created to record your interest in some
270event. For instance, if you want to wait for STDIN to become readable, you 293event. For instance, if you want to wait for STDIN to become readable, you
271would create an EV::io watcher for that: 294would create an EV::io watcher for that:
272 295
273 my $watcher = EV::io *STDIN, EV::READ, sub { 296 my $watcher = EV::io *STDIN, EV::READ, sub {
274 my ($watcher, $revents) = @_; 297 my ($watcher, $revents) = @_;
275 warn "yeah, STDIN should now be readable without blocking!\n" 298 warn "yeah, STDIN should now be readable without blocking!\n"
276 }; 299 };
277 300
278All watchers can be active (waiting for events) or inactive (paused). Only 301All watchers can be active (waiting for events) or inactive (paused). Only
279active watchers will have their callbacks invoked. All callbacks will be 302active watchers will have their callbacks invoked. All callbacks will be
280called with at least two arguments: the watcher and a bitmask of received 303called with at least two arguments: the watcher and a bitmask of received
281events. 304events.
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394Example: Register an I/O watcher for some UDP socket but do not keep the 417Example: Register an I/O watcher for some UDP socket but do not keep the
395event loop from running just because of that watcher. 418event loop from running just because of that watcher.
396 419
397 my $udp_socket = ... 420 my $udp_socket = ...
398 my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... }; 421 my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... };
399 $1000udp_watcher->keepalive (0); 422 $udp_watcher->keepalive (0);
400 423
401=item $loop = $w->loop 424=item $loop = $w->loop
402 425
403Return the loop that this watcher is attached to. 426Return the loop that this watcher is attached to.
404 427
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533This time simply fires at the wallclock time C<$at> and doesn't repeat. It 556This time simply fires at the wallclock time C<$at> and doesn't repeat. It
534will not adjust when a time jump occurs, that is, if it is to be run 557will not adjust when a time jump occurs, that is, if it is to be run
535at January 1st 2011 then it will run when the system time reaches or 558at January 1st 2011 then it will run when the system time reaches or
536surpasses this time. 559surpasses this time.
537 560
538=item * non-repeating interval timer ($interval > 0, $reschedule_cb = 0) 561=item * repeating interval timer ($interval > 0, $reschedule_cb = 0)
539 562
540In this mode the watcher will always be scheduled to time out at the 563In this mode the watcher will always be scheduled to time out at the
541next C<$at + N * $interval> time (for some integer N) and then repeat, 564next C<$at + N * $interval> time (for some integer N) and then repeat,
542regardless of any time jumps. 565regardless of any time jumps.
543 566
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561time the periodic watcher gets scheduled, the reschedule callback 584time the periodic watcher gets scheduled, the reschedule callback
562($reschedule_cb) will be called with the watcher as first, and the current 585($reschedule_cb) will be called with the watcher as first, and the current
563time as second argument. 586time as second argument.
564 587
565I<This callback MUST NOT stop or destroy this or any other periodic 588I<This callback MUST NOT stop or destroy this or any other periodic
566watcher, ever>. If you need to stop it, return 1e30 and stop it 589watcher, ever, and MUST NOT call any event loop functions or methods>. If
567afterwards. 590you need to stop it, return 1e30 and stop it afterwards. You may create
591and start a C<EV::prepare> watcher for this task.
568 592
569It must return the next time to trigger, based on the passed time value 593It must return the next time to trigger, based on the passed time value
570(that is, the lowest time value larger than to the second argument). It 594(that is, the lowest time value larger than or equal to to the second
571will usually be called just before the callback will be triggered, but 595argument). It will usually be called just before the callback will be
572might be called at other times, too. 596triggered, but might be called at other times, too.
573 597
574This can be used to create very complex timers, such as a timer that 598This can be used to create very complex timers, such as a timer that
575triggers on each midnight, local time (actually 24 hours after the last 599triggers on each midnight, local time (actually 24 hours after the last
576midnight, to keep the example simple. If you know a way to do it correctly 600midnight, to keep the example simple. If you know a way to do it correctly
577in about the same space (without requiring elaborate modules), drop me a 601in about the same space (without requiring elaborate modules), drop me a
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935for more details. 959for more details.
936 960
937In short, this watcher is most useful on BSD systems without working 961In short, this watcher is most useful on BSD systems without working
938kqueue to still be able to handle a large number of sockets: 962kqueue to still be able to handle a large number of sockets:
939 963
940 my $socket_loop; 964 my $socket_loop;
941 965
942 # check wether we use SELECT or POLL _and_ KQUEUE is supported 966 # check wether we use SELECT or POLL _and_ KQUEUE is supported
943 if ( 967 if (
944 (EV::backend & (EV::BACKEND_POLL | EV::BACKEND_SELECT)) 968 (EV::backend & (EV::BACKEND_POLL | EV::BACKEND_SELECT))
945 && (EV::supported_backends & EV::embeddable_backends & EV::BACKEND_KQUEUE) 969 && (EV::supported_backends & EV::embeddable_backends & EV::BACKEND_KQUEUE)
946 ) { 970 ) {
947 # use kqueue for sockets 971 # use kqueue for sockets
948 $socket_loop = new EV::Loop EV::BACKEND_KQUEUE | EV::FLAG_NOENV; 972 $socket_loop = new EV::Loop EV::BACKEND_KQUEUE | EV::FLAG_NOENV;
949 } 973 }
950 974
951 # use the default loop otherwise 975 # use the default loop otherwise
952 $socket_loop ||= EV::default_loop; 976 $socket_loop ||= EV::default_loop;
953 977
954=over 4 978=over 4
955 979
956=item $w = EV::embed $otherloop, $callback 980=item $w = EV::embed $otherloop, $callback
957 981
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965I/O activity. The C<$callback> should alwas be specified as C<undef> in 989I/O activity. The C<$callback> should alwas be specified as C<undef> in
966this version of EV, which means the embedded event loop will be managed 990this version of EV, which means the embedded event loop will be managed
967automatically. 991automatically.
968 992
969The C<embed_ns> variant doesn't start (activate) the newly created watcher. 993The C<embed_ns> variant doesn't start (activate) the newly created watcher.
994
995=back
996
997=head3 ASYNC WATCHERS - how to wake up another event loop
998
999Async watchers are provided by EV, but have little use in perl directly, as perl
1000neither supports threads nor direct access to signal handlers or other
1001contexts where they could be of value.
1002
1003It is, however, possible to use them from the XS level.
1004
1005Please see the libev documentation for further details.
1006
1007=over 4
1008
1009=item $w = EV::async $callback
1010
1011=item $w = EV::async_ns $callback
1012
1013=item $w->send
1014
1015=item $bool = $w->async_pending
970 1016
971=back 1017=back
972 1018
973 1019
974=head1 PERL SIGNALS 1020=head1 PERL SIGNALS
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1026 1072
1027=head1 SEE ALSO 1073=head1 SEE ALSO
1028 1074
1029L<EV::ADNS> (asynchronous DNS), L<Glib::EV> (makes Glib/Gtk2 use EV as 1075L<EV::ADNS> (asynchronous DNS), L<Glib::EV> (makes Glib/Gtk2 use EV as
1030event loop), L<EV::Glib> (embed Glib into EV), L<Coro::EV> (efficient 1076event loop), L<EV::Glib> (embed Glib into EV), L<Coro::EV> (efficient
1031coroutines with EV), L<Net::SNMP::EV> (asynchronous SNMP). 1077coroutines with EV), L<Net::SNMP::EV> (asynchronous SNMP), L<AnyEvent> for
1078event-loop agnostic and portable event driven programming.
1032 1079
1033=head1 AUTHOR 1080=head1 AUTHOR
1034 1081
1035 Marc Lehmann <schmorp@schmorp.de> 1082 Marc Lehmann <schmorp@schmorp.de>
1036 http://home.schmorp.de/ 1083 http://home.schmorp.de/
1037 1084
1038=cut 1085=cut
1039 1086

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