ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/EV/EV.pm
(Generate patch)

Comparing EV/EV.pm (file contents):
Revision 1.81 by root, Mon Dec 31 00:59:34 2007 UTC vs.
Revision 1.101 by root, Sat Jul 12 22:19:22 2008 UTC

… …
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 $w = EV::child 666, sub {
41 my ($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
76no warnings;
70use strict; 77use strict;
71 78
72BEGIN { 79BEGIN {
73 our $VERSION = '2.01'; 80 our $VERSION = '3.431';
74 use XSLoader; 81 use XSLoader;
75 XSLoader::load "EV", $VERSION; 82 XSLoader::load "EV", $VERSION;
76} 83}
77 84
78@EV::IO::ISA = 85@EV::IO::ISA =
… …
84@EV::Idle::ISA = 91@EV::Idle::ISA =
85@EV::Prepare::ISA = 92@EV::Prepare::ISA =
86@EV::Check::ISA = 93@EV::Check::ISA =
87@EV::Embed::ISA = 94@EV::Embed::ISA =
88@EV::Fork::ISA = 95@EV::Fork::ISA =
96@EV::Async::ISA =
89 "EV::Watcher"; 97 "EV::Watcher";
90 98
91@EV::Loop::Default::ISA = "EV::Loop"; 99@EV::Loop::Default::ISA = "EV::Loop";
92 100
93=head1 EVENT LOOPS 101=head1 EVENT LOOPS
… …
104default loop as this is fastest (perl-wise), best supported by other 112default loop as this is fastest (perl-wise), best supported by other
105modules (e.g. AnyEvent or Coro) and most portable event loop. 113modules (e.g. AnyEvent or Coro) and most portable event loop.
106 114
107For specific programs you can create additional event loops dynamically. 115For specific programs you can create additional event loops dynamically.
108 116
117If you want to take avdantage of kqueue (which often works properly for
118sockets only) even though the default loop doesn't enable it, you can
119I<embed> a kqueue loop into the default loop: running the default loop
120will then also service the kqueue loop to some extent. See the example in
121the section about embed watchers for an example on how to achieve that.
122
109=over 4 123=over 4
110 124
111=item $loop = new EV::loop [$flags] 125=item $loop = new EV::loop [$flags]
112 126
113Create a new event loop as per the specified flags. Please refer to the 127Create a new event loop as per the specified flags. Please refer to the
… …
123 137
124=item $loop->loop_fork 138=item $loop->loop_fork
125 139
126Must be called after a fork in the child, before entering or continuing 140Must 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 141the event loop. An alternative is to use C<EV::FLAG_FORKCHECK> which calls
128this fucntion automatically, at some performance loss (refer to the libev 142this function automatically, at some performance loss (refer to the libev
129documentation). 143documentation).
130 144
145=item $loop->loop_verify
146
147Calls C<ev_verify> to make internal consistency checks (for debugging
148libev) and abort the program if any data structures were found to be
149corrupted.
150
131=item $loop = EV::default_loop [$flags] 151=item $loop = EV::default_loop [$flags]
132 152
133Return the default loop (which is a singleton object). 153Return the default loop (which is a singleton object). Since this module
154already creates the default loop with default flags, specifying flags here
155will not have any effect unless you destroy the default loop first, which
156isn't supported. So in short: don't do it, and if you break it, you get to
157keep the pieces.
134 158
135=back 159=back
136 160
137 161
138=head1 BASIC INTERFACE 162=head1 BASIC INTERFACE
… …
268 292
269A watcher is an object that gets created to record your interest in some 293A 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 294event. For instance, if you want to wait for STDIN to become readable, you
271would create an EV::io watcher for that: 295would create an EV::io watcher for that:
272 296
273 my $watcher = EV::io *STDIN, EV::READ, sub { 297 my $watcher = EV::io *STDIN, EV::READ, sub {
274 my ($watcher, $revents) = @_; 298 my ($watcher, $revents) = @_;
275 warn "yeah, STDIN should now be readable without blocking!\n" 299 warn "yeah, STDIN should now be readable without blocking!\n"
276 }; 300 };
277 301
278All watchers can be active (waiting for events) or inactive (paused). Only 302All watchers can be active (waiting for events) or inactive (paused). Only
279active watchers will have their callbacks invoked. All callbacks will be 303active watchers will have their callbacks invoked. All callbacks will be
280called with at least two arguments: the watcher and a bitmask of received 304called with at least two arguments: the watcher and a bitmask of received
281events. 305events.
… …
394Example: Register an I/O watcher for some UDP socket but do not keep the 418Example: Register an I/O watcher for some UDP socket but do not keep the
395event loop from running just because of that watcher. 419event loop from running just because of that watcher.
396 420
397 my $udp_socket = ... 421 my $udp_socket = ...
398 my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... }; 422 my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... };
399 $1000udp_watcher->keepalive (0); 423 $udp_watcher->keepalive (0);
400 424
401=item $loop = $w->loop 425=item $loop = $w->loop
402 426
403Return the loop that this watcher is attached to. 427Return the loop that this watcher is attached to.
404 428
… …
533This time simply fires at the wallclock time C<$at> and doesn't repeat. It 557This time simply fires at the wallclock time C<$at> and doesn't repeat. It
534will not adjust when a time jump occurs, that is, if it is to be run 558will not adjust when a time jump occurs, that is, if it is to be run
535at January 1st 2011 then it will run when the system time reaches or 559at January 1st 2011 then it will run when the system time reaches or
536surpasses this time. 560surpasses this time.
537 561
538=item * non-repeating interval timer ($interval > 0, $reschedule_cb = 0) 562=item * repeating interval timer ($interval > 0, $reschedule_cb = 0)
539 563
540In this mode the watcher will always be scheduled to time out at the 564In this mode the watcher will always be scheduled to time out at the
541next C<$at + N * $interval> time (for some integer N) and then repeat, 565next C<$at + N * $interval> time (for some integer N) and then repeat,
542regardless of any time jumps. 566regardless of any time jumps.
543 567
… …
561time the periodic watcher gets scheduled, the reschedule callback 585time the periodic watcher gets scheduled, the reschedule callback
562($reschedule_cb) will be called with the watcher as first, and the current 586($reschedule_cb) will be called with the watcher as first, and the current
563time as second argument. 587time as second argument.
564 588
565I<This callback MUST NOT stop or destroy this or any other periodic 589I<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 590watcher, ever, and MUST NOT call any event loop functions or methods>. If
567afterwards. 591you need to stop it, return 1e30 and stop it afterwards. You may create
592and start a C<EV::prepare> watcher for this task.
568 593
569It must return the next time to trigger, based on the passed time value 594It 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 595(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 596argument). It will usually be called just before the callback will be
572might be called at other times, too. 597triggered, but might be called at other times, too.
573 598
574This can be used to create very complex timers, such as a timer that 599This 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 600triggers 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 601midnight, 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 602in about the same space (without requiring elaborate modules), drop me a
… …
644 669
645=head3 CHILD WATCHERS - watch out for process status changes 670=head3 CHILD WATCHERS - watch out for process status changes
646 671
647=over 4 672=over 4
648 673
649=item $w = EV::child $pid, $callback 674=item $w = EV::child $pid, $trace, $callback
650 675
651=item $w = EV::child_ns $pid, $callback 676=item $w = EV::child_ns $pid, $trace, $callback
652 677
653=item $w = $loop->child ($pid, $callback) 678=item $w = $loop->child ($pid, $trace, $callback)
654 679
655=item $w = $loop->child_ns ($pid, $callback) 680=item $w = $loop->child_ns ($pid, $trace, $callback)
656 681
657Call the callback when a status change for pid C<$pid> (or any pid if 682Call the callback when a status change for pid C<$pid> (or any pid
658C<$pid> is 0) has been received. More precisely: when the process receives 683if C<$pid> is 0) has been received (a status change happens when the
684process terminates or is killed, or, when trace is true, additionally when
685it is stopped or continued). More precisely: when the process receives
659a C<SIGCHLD>, EV will fetch the outstanding exit/wait status for all 686a C<SIGCHLD>, EV will fetch the outstanding exit/wait status for all
660changed/zombie children and call the callback. 687changed/zombie children and call the callback.
661 688
662It is valid (and fully supported) to install a child watcher after a child 689It is valid (and fully supported) to install a child watcher after a child
663has exited but before the event loop has started its next iteration (for 690has exited but before the event loop has started its next iteration (for
… …
670You can have as many pid watchers per pid as you want, they will all be 697You can have as many pid watchers per pid as you want, they will all be
671called. 698called.
672 699
673The C<child_ns> variant doesn't start (activate) the newly created watcher. 700The C<child_ns> variant doesn't start (activate) the newly created watcher.
674 701
675=item $w->set ($pid) 702=item $w->set ($pid, $trace)
676 703
677Reconfigures the watcher, see the constructor above for details. Can be called at 704Reconfigures the watcher, see the constructor above for details. Can be called at
678any time. 705any time.
679 706
680=item $current_pid = $w->pid 707=item $current_pid = $w->pid
681
682=item $old_pid = $w->pid ($new_pid)
683 708
684Returns the previously set process id and optionally set a new one. 709Returns the previously set process id and optionally set a new one.
685 710
686=item $exit_status = $w->rstatus 711=item $exit_status = $w->rstatus
687 712
… …
935for more details. 960for more details.
936 961
937In short, this watcher is most useful on BSD systems without working 962In short, this watcher is most useful on BSD systems without working
938kqueue to still be able to handle a large number of sockets: 963kqueue to still be able to handle a large number of sockets:
939 964
940 my $socket_loop; 965 my $socket_loop;
941 966
942 # check wether we use SELECT or POLL _and_ KQUEUE is supported 967 # check wether we use SELECT or POLL _and_ KQUEUE is supported
943 if ( 968 if (
944 (EV::backend & (EV::BACKEND_POLL | EV::BACKEND_SELECT)) 969 (EV::backend & (EV::BACKEND_POLL | EV::BACKEND_SELECT))
945 && (EV::supported_backends & EV::embeddable_backends & EV::BACKEND_KQUEUE) 970 && (EV::supported_backends & EV::embeddable_backends & EV::BACKEND_KQUEUE)
946 ) { 971 ) {
947 # use kqueue for sockets 972 # use kqueue for sockets
948 $socket_loop = new EV::Loop EV::BACKEND_KQUEUE | EV::FLAG_NOENV; 973 $socket_loop = new EV::Loop EV::BACKEND_KQUEUE | EV::FLAG_NOENV;
949 } 974 }
950 975
951 # use the default loop otherwise 976 # use the default loop otherwise
952 $socket_loop ||= EV::default_loop; 977 $socket_loop ||= EV::default_loop;
953 978
954=over 4 979=over 4
955 980
956=item $w = EV::embed $otherloop, $callback 981=item $w = EV::embed $otherloop[, $callback]
957 982
958=item $w = EV::embed_ns $otherloop, $callback 983=item $w = EV::embed_ns $otherloop[, $callback]
959 984
960=item $w = $loop->embed ($otherloop, $callback) 985=item $w = $loop->embed ($otherloop[, $callback])
961 986
962=item $w = $loop->embed_ns ($otherloop, $callback) 987=item $w = $loop->embed_ns ($otherloop[, $callback])
963 988
964Call the callback when the embedded event loop (C<$otherloop>) has any 989Call the callback when the embedded event loop (C<$otherloop>) has any
965I/O activity. The C<$callback> should alwas be specified as C<undef> in 990I/O activity. The C<$callback> is optional: if it is missing, then the
966this version of EV, which means the embedded event loop will be managed 991embedded event loop will be managed automatically (which is recommended),
967automatically. 992otherwise you have to invoke C<sweep> yourself.
968 993
969The C<embed_ns> variant doesn't start (activate) the newly created watcher. 994The C<embed_ns> variant doesn't start (activate) the newly created watcher.
995
996=back
997
998=head3 ASYNC WATCHERS - how to wake up another event loop
999
1000Async watchers are provided by EV, but have little use in perl directly, as perl
1001neither supports threads nor direct access to signal handlers or other
1002contexts where they could be of value.
1003
1004It is, however, possible to use them from the XS level.
1005
1006Please see the libev documentation for further details.
1007
1008=over 4
1009
1010=item $w = EV::async $callback
1011
1012=item $w = EV::async_ns $callback
1013
1014=item $w->send
1015
1016=item $bool = $w->async_pending
970 1017
971=back 1018=back
972 1019
973 1020
974=head1 PERL SIGNALS 1021=head1 PERL SIGNALS
… …
1026 1073
1027=head1 SEE ALSO 1074=head1 SEE ALSO
1028 1075
1029L<EV::ADNS> (asynchronous DNS), L<Glib::EV> (makes Glib/Gtk2 use EV as 1076L<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 1077event loop), L<EV::Glib> (embed Glib into EV), L<Coro::EV> (efficient
1031coroutines with EV), L<Net::SNMP::EV> (asynchronous SNMP). 1078coroutines with EV), L<Net::SNMP::EV> (asynchronous SNMP), L<AnyEvent> for
1079event-loop agnostic and portable event driven programming.
1032 1080
1033=head1 AUTHOR 1081=head1 AUTHOR
1034 1082
1035 Marc Lehmann <schmorp@schmorp.de> 1083 Marc Lehmann <schmorp@schmorp.de>
1036 http://home.schmorp.de/ 1084 http://home.schmorp.de/
1037 1085
1038=cut 1086=cut
1039 1087

Diff Legend

– Removed lines
+ Added lines
< Changed lines
> Changed lines