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1NAME 1NAME
2 EV - perl interface to libev, a high performance full-featured event 2 EV - perl interface to libev, a high performance full-featured event
3 loop 3 loop
4 4
5SYNOPSIS 5SYNOPSIS
6 use EV; 6 use EV;
7 7
8 # TIMERS 8 # TIMERS
9 9
10 my $w = EV::timer 2, 0, sub { 10 my $w = EV::timer 2, 0, sub {
11 warn "is called after 2s"; 11 warn "is called after 2s";
12 }; 12 };
13 13
14 my $w = EV::timer 2, 2, sub { 14 my $w = EV::timer 2, 2, sub {
15 warn "is called roughly every 2s (repeat = 2)"; 15 warn "is called roughly every 2s (repeat = 2)";
16 }; 16 };
17 17
18 undef $w; # destroy event watcher again 18 undef $w; # destroy event watcher again
19 19
20 my $w = EV::periodic 0, 60, 0, sub { 20 my $w = EV::periodic 0, 60, 0, sub {
21 warn "is called every minute, on the minute, exactly"; 21 warn "is called every minute, on the minute, exactly";
22 }; 22 };
23 23
24 # IO 24 # IO
25 25
26 my $w = EV::io *STDIN, EV::READ, sub { 26 my $w = EV::io *STDIN, EV::READ, sub {
27 my ($w, $revents) = @_; # all callbacks receive the watcher and event mask 27 my ($w, $revents) = @_; # all callbacks receive the watcher and event mask
28 warn "stdin is readable, you entered: ", <STDIN>; 28 warn "stdin is readable, you entered: ", <STDIN>;
29 }; 29 };
30 30
31 # SIGNALS 31 # SIGNALS
32 32
33 my $w = EV::signal 'QUIT', sub { 33 my $w = EV::signal 'QUIT', sub {
34 warn "sigquit received\n"; 34 warn "sigquit received\n";
35 }; 35 };
36 36
37 # CHILD/PID STATUS CHANGES 37 # CHILD/PID STATUS CHANGES
38 38
39 my $w = EV::child 666, 0, sub { 39 my $w = EV::child 666, 0, sub {
40 my ($w, $revents) = @_; 40 my ($w, $revents) = @_;
41 my $status = $w->rstatus; 41 my $status = $w->rstatus;
42 }; 42 };
43 43
44 # STAT CHANGES 44 # STAT CHANGES
45 my $w = EV::stat "/etc/passwd", 10, sub { 45 my $w = EV::stat "/etc/passwd", 10, sub {
46 my ($w, $revents) = @_; 46 my ($w, $revents) = @_;
47 warn $w->path, " has changed somehow.\n"; 47 warn $w->path, " has changed somehow.\n";
48 }; 48 };
49 49
50 # MAINLOOP 50 # MAINLOOP
51 EV::loop; # loop until EV::unloop is called or all watchers stop 51 EV::loop; # loop until EV::unloop is called or all watchers stop
52 EV::loop EV::LOOP_ONESHOT; # block until at least one event could be handled 52 EV::loop EV::LOOP_ONESHOT; # block until at least one event could be handled
53 EV::loop EV::LOOP_NONBLOCK; # try to handle same events, but do not block 53 EV::loop EV::LOOP_NONBLOCK; # try to handle same events, but do not block
54
55BEFORE YOU START USING THIS MODULE
56 If you only need timer, I/O, signal, child and idle watchers and not the
57 advanced functionality of this module, consider using AnyEvent instead,
58 specifically the simplified API described in AE.
59
60 When used with EV as backend, the AE API is as fast as the native EV
61 API, but your programs/modules will still run with many other event
62 loops.
54 63
55DESCRIPTION 64DESCRIPTION
56 This module provides an interface to libev 65 This module provides an interface to libev
57 (<http://software.schmorp.de/pkg/libev.html>). While the documentation 66 (<http://software.schmorp.de/pkg/libev.html>). While the documentation
58 below is comprehensive, one might also consult the documentation of 67 below is comprehensive, one might also consult the documentation of
59 libev itself (<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod>) 68 libev itself (<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod> or
60 for more subtle details on watcher semantics or some discussion on the 69 perldoc EV::libev) for more subtle details on watcher semantics or some
61 available backends, or how to force a specific backend with 70 discussion on the available backends, or how to force a specific backend
62 "LIBEV_FLAGS", or just about in any case because it has much more 71 with "LIBEV_FLAGS", or just about in any case because it has much more
63 detailed information. 72 detailed information.
64 73
65 This module is very fast and scalable. It is actually so fast that you 74 This module is very fast and scalable. It is actually so fast that you
66 can use it through the AnyEvent module, stay portable to other event 75 can use it through the AnyEvent module, stay portable to other event
67 loops (if you don't rely on any watcher types not available through it) 76 loops (if you don't rely on any watcher types not available through it)
68 and still be faster than with any other event loop currently supported 77 and still be faster than with any other event loop currently supported
69 in Perl. 78 in Perl.
79
80 PORTING FROM EV 3.X to 4.X
81 EV version 4 introduces a number of incompatible changes summarised
82 here. According to the depreciation strategy used by libev, there is a
83 compatibility layer in place so programs should continue to run
84 unchanged (the XS interface lacks this layer, so programs using that one
85 need to be updated).
86
87 This compatibility layer will be switched off in some future release.
88
89 All changes relevant to Perl are renames of symbols, functions and
90 methods:
91
92 EV::loop => EV::run
93 EV::LOOP_NONBLOCK => EV::RUN_NOWAIT
94 EV::LOOP_ONESHOT => EV::RUN_ONCE
95
96 EV::unloop => EV::break
97 EV::UNLOOP_CANCEL => EV::BREAK_CANCEL
98 EV::UNLOOP_ONE => EV::BREAK_ONE
99 EV::UNLOOP_ALL => EV::BREAK_ALL
100
101 EV::TIMEOUT => EV::TIMER
102
103 EV::loop_count => EV::iteration
104 EV::loop_depth => EV::depth
105 EV::loop_verify => EV::verify
106
107 The loop object methods corresponding to the functions above have been
108 similarly renamed.
109
110 MODULE EXPORTS
111 This module does not export any symbols.
70 112
71EVENT LOOPS 113EVENT LOOPS
72 EV supports multiple event loops: There is a single "default event loop" 114 EV supports multiple event loops: There is a single "default event loop"
73 that can handle everything including signals and child watchers, and any 115 that can handle everything including signals and child watchers, and any
74 number of "dynamic event loops" that can use different backends (with 116 number of "dynamic event loops" that can use different backends (with
81 default loop as this is fastest (perl-wise), best supported by other 123 default loop as this is fastest (perl-wise), best supported by other
82 modules (e.g. AnyEvent or Coro) and most portable event loop. 124 modules (e.g. AnyEvent or Coro) and most portable event loop.
83 125
84 For specific programs you can create additional event loops dynamically. 126 For specific programs you can create additional event loops dynamically.
85 127
128 If you want to take advantage of kqueue (which often works properly for
129 sockets only) even though the default loop doesn't enable it, you can
130 *embed* a kqueue loop into the default loop: running the default loop
131 will then also service the kqueue loop to some extent. See the example
132 in the section about embed watchers for an example on how to achieve
133 that.
134
86 $loop = new EV::loop [$flags] 135 $loop = new EV::Loop [$flags]
87 Create a new event loop as per the specified flags. Please refer to 136 Create a new event loop as per the specified flags. Please refer to
88 the "ev_loop_new ()" function description in the libev documentation 137 the "ev_loop_new ()" function description in the libev documentation
89 (<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#GLOBAL_FUNCTI 138 (<http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#GLOBAL_FUNCTI
90 ONS>) for more info. 139 ONS>, or locally-installed as EV::libev manpage) for more info.
91 140
92 The loop will automatically be destroyed when it is no longer 141 The loop will automatically be destroyed when it is no longer
93 referenced by any watcher and the loop object goes out of scope. 142 referenced by any watcher and the loop object goes out of scope.
94 143
95 Using "EV::FLAG_FORKCHECK" is recommended, as only the default event 144 If you are not embedding the loop, then Using "EV::FLAG_FORKCHECK"
96 loop is protected by this module. 145 is recommended, as only the default event loop is protected by this
146 module. If you *are* embedding this loop in the default loop, this
147 is not necessary, as "EV::embed" automatically does the right thing
148 on fork.
97 149
98 $loop->loop_fork 150 $loop->loop_fork
99 Must be called after a fork in the child, before entering or 151 Must be called after a fork in the child, before entering or
100 continuing the event loop. An alternative is to use 152 continuing the event loop. An alternative is to use
101 "EV::FLAG_FORKCHECK" which calls this function automatically, at 153 "EV::FLAG_FORKCHECK" which calls this function automatically, at
102 some performance loss (refer to the libev documentation). 154 some performance loss (refer to the libev documentation).
103 155
104 $loop->loop_verify 156 $loop->loop_verify
105 Calls "ev_verify" to make internal consistency checks (for debugging 157 Calls "ev_verify" to make internal consistency checks (for debugging
106 libev) and abort the program if any data structures wree found to be 158 libev) and abort the program if any data structures were found to be
107 corrupted. 159 corrupted.
108 160
109 $loop = EV::default_loop [$flags] 161 $loop = EV::default_loop [$flags]
110 Return the default loop (which is a singleton object). Since this 162 Return the default loop (which is a singleton object). Since this
111 module already creates the default loop with default flags, 163 module already creates the default loop with default flags,
112 specifying flags here will not have any effect unless you destroy 164 specifying flags here will not have any effect unless you destroy
113 the default loop. 165 the default loop first, which isn't supported. So in short: don't do
166 it, and if you break it, you get to keep the pieces.
114 167
115BASIC INTERFACE 168BASIC INTERFACE
116 $EV::DIED 169 $EV::DIED
117 Must contain a reference to a function that is called when a 170 Must contain a reference to a function that is called when a
118 callback throws an exception (with $@ containing the error). The 171 callback throws an exception (with $@ containing the error). The
135 Returns the current time in (fractional) seconds since the epoch. 188 Returns the current time in (fractional) seconds since the epoch.
136 189
137 $time = EV::now 190 $time = EV::now
138 $time = $loop->now 191 $time = $loop->now
139 Returns the time the last event loop iteration has been started. 192 Returns the time the last event loop iteration has been started.
140 This is the time that (relative) timers are based on, and refering 193 This is the time that (relative) timers are based on, and referring
141 to it is usually faster then calling EV::time. 194 to it is usually faster then calling EV::time.
195
196 EV::now_update
197 $loop->now_update
198 Establishes the current time by querying the kernel, updating the
199 time returned by "EV::now" in the progress. This is a costly
200 operation and is usually done automatically within "EV::loop".
201
202 This function is rarely useful, but when some event callback runs
203 for a very long time without entering the event loop, updating
204 libev's idea of the current time is a good idea.
205
206 EV::suspend
207 $loop->suspend
208 EV::resume
209 $loop->resume
210 These two functions suspend and resume a loop, for use when the loop
211 is not used for a while and timeouts should not be processed.
212
213 A typical use case would be an interactive program such as a game:
214 When the user presses "^Z" to suspend the game and resumes it an
215 hour later it would be best to handle timeouts as if no time had
216 actually passed while the program was suspended. This can be
217 achieved by calling "suspend" in your "SIGTSTP" handler, sending
218 yourself a "SIGSTOP" and calling "resume" directly afterwards to
219 resume timer processing.
220
221 Effectively, all "timer" watchers will be delayed by the time spend
222 between "suspend" and "resume", and all "periodic" watchers will be
223 rescheduled (that is, they will lose any events that would have
224 occured while suspended).
225
226 After calling "suspend" you must not call *any* function on the
227 given loop other than "resume", and you must not call "resume"
228 without a previous call to "suspend".
229
230 Calling "suspend"/"resume" has the side effect of updating the event
231 loop time (see "now_update").
142 232
143 $backend = EV::backend 233 $backend = EV::backend
144 $backend = $loop->backend 234 $backend = $loop->backend
145 Returns an integer describing the backend used by libev 235 Returns an integer describing the backend used by libev
146 (EV::METHOD_SELECT or EV::METHOD_EPOLL). 236 (EV::BACKEND_SELECT or EV::BACKEND_EPOLL).
147 237
148 EV::loop [$flags] 238 EV::loop [$flags]
149 $loop->loop ([$flags]) 239 $loop->loop ([$flags])
150 Begin checking for events and calling callbacks. It returns when a 240 Begin checking for events and calling callbacks. It returns when a
151 callback calls EV::unloop. 241 callback calls EV::unloop.
165 EV::loop will return as fast as possible. 255 EV::loop will return as fast as possible.
166 256
167 $count = EV::loop_count 257 $count = EV::loop_count
168 $count = $loop->loop_count 258 $count = $loop->loop_count
169 Return the number of times the event loop has polled for new events. 259 Return the number of times the event loop has polled for new events.
170 Sometiems useful as a generation counter. 260 Sometimes useful as a generation counter.
171 261
172 EV::once $fh_or_undef, $events, $timeout, $cb->($revents) 262 EV::once $fh_or_undef, $events, $timeout, $cb->($revents)
173 $loop->once ($fh_or_undef, $events, $timeout, $cb->($revents)) 263 $loop->once ($fh_or_undef, $events, $timeout, $cb->($revents))
174 This function rolls together an I/O and a timer watcher for a single 264 This function rolls together an I/O and a timer watcher for a single
175 one-shot event without the need for managing a watcher object. 265 one-shot event without the need for managing a watcher object.
184 Otherwise a EV::timer with this value will be started. 274 Otherwise a EV::timer with this value will be started.
185 275
186 When an error occurs or either the timeout or I/O watcher triggers, 276 When an error occurs or either the timeout or I/O watcher triggers,
187 then the callback will be called with the received event set (in 277 then the callback will be called with the received event set (in
188 general you can expect it to be a combination of "EV::ERROR", 278 general you can expect it to be a combination of "EV::ERROR",
189 "EV::READ", "EV::WRITE" and "EV::TIMEOUT"). 279 "EV::READ", "EV::WRITE" and "EV::TIMER").
190 280
191 EV::once doesn't return anything: the watchers stay active till 281 EV::once doesn't return anything: the watchers stay active till
192 either of them triggers, then they will be stopped and freed, and 282 either of them triggers, then they will be stopped and freed, and
193 the callback invoked. 283 the callback invoked.
194 284
209 $loop->set_timeout_collect_interval ($time) 299 $loop->set_timeout_collect_interval ($time)
210 These advanced functions set the minimum block interval when polling 300 These advanced functions set the minimum block interval when polling
211 for I/O events and the minimum wait interval for timer events. See 301 for I/O events and the minimum wait interval for timer events. See
212 the libev documentation at 302 the libev documentation at
213 <http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#FUNCTIONS_CONT 303 <http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#FUNCTIONS_CONT
214 ROLLING_THE_EVENT_LOOP> for a more detailed discussion. 304 ROLLING_THE_EVENT_LOOP> (locally installed as EV::libev) for a more
305 detailed discussion.
306
307 $count = EV::pending_count
308 $count = $loop->pending_count
309 Returns the number of currently pending watchers.
310
311 EV::invoke_pending
312 $loop->invoke_pending
313 Invoke all currently pending watchers.
215 314
216WATCHER OBJECTS 315WATCHER OBJECTS
217 A watcher is an object that gets created to record your interest in some 316 A watcher is an object that gets created to record your interest in some
218 event. For instance, if you want to wait for STDIN to become readable, 317 event. For instance, if you want to wait for STDIN to become readable,
219 you would create an EV::io watcher for that: 318 you would create an EV::io watcher for that:
220 319
221 my $watcher = EV::io *STDIN, EV::READ, sub { 320 my $watcher = EV::io *STDIN, EV::READ, sub {
222 my ($watcher, $revents) = @_; 321 my ($watcher, $revents) = @_;
223 warn "yeah, STDIN should now be readable without blocking!\n" 322 warn "yeah, STDIN should now be readable without blocking!\n"
224 }; 323 };
225 324
226 All watchers can be active (waiting for events) or inactive (paused). 325 All watchers can be active (waiting for events) or inactive (paused).
227 Only active watchers will have their callbacks invoked. All callbacks 326 Only active watchers will have their callbacks invoked. All callbacks
228 will be called with at least two arguments: the watcher and a bitmask of 327 will be called with at least two arguments: the watcher and a bitmask of
229 received events. 328 received events.
230 329
231 Each watcher type has its associated bit in revents, so you can use the 330 Each watcher type has its associated bit in revents, so you can use the
232 same callback for multiple watchers. The event mask is named after the 331 same callback for multiple watchers. The event mask is named after the
233 type, i..e. EV::child sets EV::CHILD, EV::prepare sets EV::PREPARE, 332 type, i.e. EV::child sets EV::CHILD, EV::prepare sets EV::PREPARE,
234 EV::periodic sets EV::PERIODIC and so on, with the exception of I/O 333 EV::periodic sets EV::PERIODIC and so on, with the exception of I/O
235 events (which can set both EV::READ and EV::WRITE bits), and EV::timer 334 events (which can set both EV::READ and EV::WRITE bits).
236 (which uses EV::TIMEOUT).
237 335
238 In the rare case where one wants to create a watcher but not start it at 336 In the rare case where one wants to create a watcher but not start it at
239 the same time, each constructor has a variant with a trailing "_ns" in 337 the same time, each constructor has a variant with a trailing "_ns" in
240 its name, e.g. EV::io has a non-starting variant EV::io_ns and so on. 338 its name, e.g. EV::io has a non-starting variant EV::io_ns and so on.
241 339
306 the watcher isn't pending it does nothing and returns 0. 404 the watcher isn't pending it does nothing and returns 0.
307 405
308 $previous_state = $w->keepalive ($bool) 406 $previous_state = $w->keepalive ($bool)
309 Normally, "EV::loop" will return when there are no active watchers 407 Normally, "EV::loop" will return when there are no active watchers
310 (which is a "deadlock" because no progress can be made anymore). 408 (which is a "deadlock" because no progress can be made anymore).
311 This is convinient because it allows you to start your watchers (and 409 This is convenient because it allows you to start your watchers (and
312 your jobs), call "EV::loop" once and when it returns you know that 410 your jobs), call "EV::loop" once and when it returns you know that
313 all your jobs are finished (or they forgot to register some watchers 411 all your jobs are finished (or they forgot to register some watchers
314 for their task :). 412 for their task :).
315 413
316 Sometimes, however, this gets in your way, for example when the 414 Sometimes, however, this gets in your way, for example when the
323 421
324 In this case you can clear the keepalive status, which means that 422 In this case you can clear the keepalive status, which means that
325 even though your watcher is active, it won't keep "EV::loop" from 423 even though your watcher is active, it won't keep "EV::loop" from
326 returning. 424 returning.
327 425
328 The initial value for keepalive is true (enabled), and you cna 426 The initial value for keepalive is true (enabled), and you can
329 change it any time. 427 change it any time.
330 428
331 Example: Register an I/O watcher for some UDP socket but do not keep 429 Example: Register an I/O watcher for some UDP socket but do not keep
332 the event loop from running just because of that watcher. 430 the event loop from running just because of that watcher.
333 431
334 my $udp_socket = ... 432 my $udp_socket = ...
335 my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... }; 433 my $udp_watcher = EV::io $udp_socket, EV::READ, sub { ... };
336 $1000udp_watcher->keepalive (0); 434 $udp_watcher->keepalive (0);
337 435
338 $loop = $w->loop 436 $loop = $w->loop
339 Return the loop that this watcher is attached to. 437 Return the loop that this watcher is attached to.
340 438
341WATCHER TYPES 439WATCHER TYPES
507 Return the time that the watcher is expected to trigger next. 605 Return the time that the watcher is expected to trigger next.
508 606
509 SIGNAL WATCHERS - signal me when a signal gets signalled! 607 SIGNAL WATCHERS - signal me when a signal gets signalled!
510 $w = EV::signal $signal, $callback 608 $w = EV::signal $signal, $callback
511 $w = EV::signal_ns $signal, $callback 609 $w = EV::signal_ns $signal, $callback
610 $w = $loop->signal ($signal, $callback)
611 $w = $loop->signal_ns ($signal, $callback)
512 Call the callback when $signal is received (the signal can be 612 Call the callback when $signal is received (the signal can be
513 specified by number or by name, just as with "kill" or %SIG). 613 specified by number or by name, just as with "kill" or %SIG).
614
615 Only one event loop can grab a given signal - attempting to grab the
616 same signal from two EV loops will crash the program immediately or
617 cause data corruption.
514 618
515 EV will grab the signal for the process (the kernel only allows one 619 EV will grab the signal for the process (the kernel only allows one
516 component to receive a signal at a time) when you start a signal 620 component to receive a signal at a time) when you start a signal
517 watcher, and removes it again when you stop it. Perl does the same 621 watcher, and removes it again when you stop it. Perl does the same
518 when you add/remove callbacks to %SIG, so watch out. 622 when you add/remove callbacks to %SIG, so watch out.
692 $w = $loop->check_ns ($callback) 796 $w = $loop->check_ns ($callback)
693 Call the callback just after the process wakes up again (after it 797 Call the callback just after the process wakes up again (after it
694 has gathered events), but before any other callbacks have been 798 has gathered events), but before any other callbacks have been
695 invoked. 799 invoked.
696 800
697 This is used to integrate other event-based software into the EV 801 This can be used to integrate other event-based software into the EV
698 mainloop: You register a prepare callback and in there, you create 802 mainloop: You register a prepare callback and in there, you create
699 io and timer watchers as required by the other software. Here is a 803 io and timer watchers as required by the other software. Here is a
700 real-world example of integrating Net::SNMP (with some details left 804 real-world example of integrating Net::SNMP (with some details left
701 out): 805 out):
702 806
733 # make the dispatcher handle any new stuff 837 # make the dispatcher handle any new stuff
734 ... not shown 838 ... not shown
735 }; 839 };
736 840
737 The callbacks of the created watchers will not be called as the 841 The callbacks of the created watchers will not be called as the
738 watchers are destroyed before this cna happen (remember EV::check 842 watchers are destroyed before this can happen (remember EV::check
739 gets called first). 843 gets called first).
740 844
741 The "check_ns" variant doesn't start (activate) the newly created 845 The "check_ns" variant doesn't start (activate) the newly created
742 watcher. 846 watcher.
847
848 EV::CHECK constant issues
849 Like all other watcher types, there is a bitmask constant for use in
850 $revents and other places. The "EV::CHECK" is special as it has the
851 same name as the "CHECK" sub called by Perl. This doesn't cause big
852 issues on newer perls (beginning with 5.8.9), but it means thatthe
853 constant must be *inlined*, i.e. runtime calls will not work. That
854 means that as long as you always "use EV" and then "EV::CHECK" you
855 are on the safe side.
743 856
744 FORK WATCHERS - the audacity to resume the event loop after a fork 857 FORK WATCHERS - the audacity to resume the event loop after a fork
745 Fork watchers are called when a "fork ()" was detected. The invocation 858 Fork watchers are called when a "fork ()" was detected. The invocation
746 is done before the event loop blocks next and before "check" watchers 859 is done before the event loop blocks next and before "check" watchers
747 are being called, and only in the child after the fork. 860 are being called, and only in the child after the fork.
762 embedded loop, other types of watchers might be handled in a delayed or 875 embedded loop, other types of watchers might be handled in a delayed or
763 incorrect fashion and must not be used). 876 incorrect fashion and must not be used).
764 877
765 See the libev documentation at 878 See the libev documentation at
766 <http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#code_ev_embed_code 879 <http://pod.tst.eu/http://cvs.schmorp.de/libev/ev.pod#code_ev_embed_code
767 _when_one_backend_> for more details. 880 _when_one_backend_> (locally installed as EV::libev) for more details.
768 881
769 In short, this watcher is most useful on BSD systems without working 882 In short, this watcher is most useful on BSD systems without working
770 kqueue to still be able to handle a large number of sockets: 883 kqueue to still be able to handle a large number of sockets:
771 884
772 my $socket_loop; 885 my $socket_loop;
773 886
774 # check wether we use SELECT or POLL _and_ KQUEUE is supported 887 # check wether we use SELECT or POLL _and_ KQUEUE is supported
775 if ( 888 if (
776 (EV::backend & (EV::BACKEND_POLL | EV::BACKEND_SELECT)) 889 (EV::backend & (EV::BACKEND_POLL | EV::BACKEND_SELECT))
777 && (EV::supported_backends & EV::embeddable_backends & EV::BACKEND_KQUEUE) 890 && (EV::supported_backends & EV::embeddable_backends & EV::BACKEND_KQUEUE)
778 ) { 891 ) {
779 # use kqueue for sockets 892 # use kqueue for sockets
780 $socket_loop = new EV::Loop EV::BACKEND_KQUEUE | EV::FLAG_NOENV; 893 $socket_loop = new EV::Loop EV::BACKEND_KQUEUE | EV::FLAG_NOENV;
781 } 894 }
782 895
783 # use the default loop otherwise 896 # use the default loop otherwise
784 $socket_loop ||= EV::default_loop; 897 $socket_loop ||= EV::default_loop;
785 898
786 $w = EV::embed $otherloop, $callback 899 $w = EV::embed $otherloop[, $callback]
787 $w = EV::embed_ns $otherloop, $callback 900 $w = EV::embed_ns $otherloop[, $callback]
788 $w = $loop->embed ($otherloop, $callback) 901 $w = $loop->embed ($otherloop[, $callback])
789 $w = $loop->embed_ns ($otherloop, $callback) 902 $w = $loop->embed_ns ($otherloop[, $callback])
790 Call the callback when the embedded event loop ($otherloop) has any 903 Call the callback when the embedded event loop ($otherloop) has any
791 I/O activity. The $callback should alwas be specified as "undef" in 904 I/O activity. The $callback is optional: if it is missing, then the
792 this version of EV, which means the embedded event loop will be 905 embedded event loop will be managed automatically (which is
793 managed automatically. 906 recommended), otherwise you have to invoke "sweep" yourself.
794 907
795 The "embed_ns" variant doesn't start (activate) the newly created 908 The "embed_ns" variant doesn't start (activate) the newly created
796 watcher. 909 watcher.
797 910
798 ASYNC WATCHERS - how to wake up another event loop 911 ASYNC WATCHERS - how to wake up another event loop
799 Async watchers are provided by EV, but have little use in perl directly, 912 Async watchers are provided by EV, but have little use in perl directly,
800 as perl neither supports threads nor direct access to signal handlers or 913 as perl neither supports threads running in parallel nor direct access
801 other contexts where they could be of value. 914 to signal handlers or other contexts where they could be of value.
802 915
803 It is, however, possible to use them from the XS level. 916 It is, however, possible to use them from the XS level.
804 917
805 Please see the libev documentation for further details. 918 Please see the libev documentation for further details.
806 919
825 my $async_check = EV::check sub { }; 938 my $async_check = EV::check sub { };
826 939
827 This ensures that perl gets into control for a short time to handle any 940 This ensures that perl gets into control for a short time to handle any
828 pending signals, and also ensures (slightly) slower overall operation. 941 pending signals, and also ensures (slightly) slower overall operation.
829 942
830THREADS 943ITHREADS
831 Threads are not supported by this module in any way. Perl pseudo-threads 944 Ithreads are not supported by this module in any way. Perl
832 is evil stuff and must die. As soon as Perl gains real threads I will 945 pseudo-threads is evil stuff and must die. Real threads as provided by
833 work on thread support for it. 946 Coro are fully supported (and enhanced support is available via
947 Coro::EV).
834 948
835FORK 949FORK
836 Most of the "improved" event delivering mechanisms of modern operating 950 Most of the "improved" event delivering mechanisms of modern operating
837 systems have quite a few problems with fork(2) (to put it bluntly: it is 951 systems have quite a few problems with fork(2) (to put it bluntly: it is
838 not supported and usually destructive). Libev makes it possible to work 952 not supported and usually destructive). Libev makes it possible to work
854 loop), EV::Glib (embed Glib into EV), Coro::EV (efficient coroutines 968 loop), EV::Glib (embed Glib into EV), Coro::EV (efficient coroutines
855 with EV), Net::SNMP::EV (asynchronous SNMP), AnyEvent for event-loop 969 with EV), Net::SNMP::EV (asynchronous SNMP), AnyEvent for event-loop
856 agnostic and portable event driven programming. 970 agnostic and portable event driven programming.
857 971
858AUTHOR 972AUTHOR
859 Marc Lehmann <schmorp@schmorp.de> 973 Marc Lehmann <schmorp@schmorp.de>
860 http://home.schmorp.de/ 974 http://home.schmorp.de/
861 975

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