[ViewVC] Diff of: cvs/libev/ev.pod

Comparing libev/ev.pod (file contents):
Revision 1.23 by root, Mon Nov 12 18:40:21 2007 UTC vs.
Revision 1.37 by root, Sat Nov 24 07:20:43 2007 UTC

…		…
45		45
46	Libev represents time as a single floating point number, representing the	46	Libev represents time as a single floating point number, representing the
47	(fractional) number of seconds since the (POSIX) epoch (somewhere near	47	(fractional) number of seconds since the (POSIX) epoch (somewhere near
48	the beginning of 1970, details are complicated, don't ask). This type is	48	the beginning of 1970, details are complicated, don't ask). This type is
49	called C<ev_tstamp>, which is what you should use too. It usually aliases	49	called C<ev_tstamp>, which is what you should use too. It usually aliases
50	to the double type in C.	50	to the C<double> type in C, and when you need to do any calculations on
		51	it, you should treat it as such.
		52
51		53
52	=head1 GLOBAL FUNCTIONS	54	=head1 GLOBAL FUNCTIONS
53		55
54	These functions can be called anytime, even before initialising the	56	These functions can be called anytime, even before initialising the
55	library in any way.	57	library in any way.
56		58
57	=over 4	59	=over 4
58		60
59	=item ev_tstamp ev_time ()	61	=item ev_tstamp ev_time ()
60		62
61	Returns the current time as libev would use it.	63	Returns the current time as libev would use it. Please note that the
		64	C<ev_now> function is usually faster and also often returns the timestamp
		65	you actually want to know.
62		66
63	=item int ev_version_major ()	67	=item int ev_version_major ()
64		68
65	=item int ev_version_minor ()	69	=item int ev_version_minor ()
66		70
…		…
73	Usually, it's a good idea to terminate if the major versions mismatch,	77	Usually, it's a good idea to terminate if the major versions mismatch,
74	as this indicates an incompatible change. Minor versions are usually	78	as this indicates an incompatible change. Minor versions are usually
75	compatible to older versions, so a larger minor version alone is usually	79	compatible to older versions, so a larger minor version alone is usually
76	not a problem.	80	not a problem.
77		81
		82	Example: make sure we haven't accidentally been linked against the wrong
		83	version:
		84
		85	assert (("libev version mismatch",
		86	ev_version_major () == EV_VERSION_MAJOR
		87	&& ev_version_minor () >= EV_VERSION_MINOR));
		88
		89	=item unsigned int ev_supported_backends ()
		90
		91	Return the set of all backends (i.e. their corresponding C<EV_BACKEND_*>
		92	value) compiled into this binary of libev (independent of their
		93	availability on the system you are running on). See C<ev_default_loop> for
		94	a description of the set values.
		95
		96	Example: make sure we have the epoll method, because yeah this is cool and
		97	a must have and can we have a torrent of it please!!!11
		98
		99	assert (("sorry, no epoll, no sex",
		100	ev_supported_backends () & EVBACKEND_EPOLL));
		101
		102	=item unsigned int ev_recommended_backends ()
		103
		104	Return the set of all backends compiled into this binary of libev and also
		105	recommended for this platform. This set is often smaller than the one
		106	returned by C<ev_supported_backends>, as for example kqueue is broken on
		107	most BSDs and will not be autodetected unless you explicitly request it
		108	(assuming you know what you are doing). This is the set of backends that
		109	libev will probe for if you specify no backends explicitly.
		110
		111	=item unsigned int ev_embeddable_backends ()
		112
		113	Returns the set of backends that are embeddable in other event loops. This
		114	is the theoretical, all-platform, value. To find which backends
		115	might be supported on the current system, you would need to look at
		116	C<ev_embeddable_backends () & ev_supported_backends ()>, likewise for
		117	recommended ones.
		118
		119	See the description of C<ev_embed> watchers for more info.
		120
78	=item ev_set_allocator (void (cb)(void *ptr, long size))	121	=item ev_set_allocator (void (cb)(void *ptr, long size))
79		122
80	Sets the allocation function to use (the prototype is similar to the	123	Sets the allocation function to use (the prototype is similar to the
81	realloc C function, the semantics are identical). It is used to allocate	124	realloc C function, the semantics are identical). It is used to allocate
82	and free memory (no surprises here). If it returns zero when memory	125	and free memory (no surprises here). If it returns zero when memory
…		…
84	destructive action. The default is your system realloc function.	127	destructive action. The default is your system realloc function.
85		128
86	You could override this function in high-availability programs to, say,	129	You could override this function in high-availability programs to, say,
87	free some memory if it cannot allocate memory, to use a special allocator,	130	free some memory if it cannot allocate memory, to use a special allocator,
88	or even to sleep a while and retry until some memory is available.	131	or even to sleep a while and retry until some memory is available.
		132
		133	Example: replace the libev allocator with one that waits a bit and then
		134	retries: better than mine).
		135
		136	static void *
		137	persistent_realloc (void *ptr, long size)
		138	{
		139	for (;;)
		140	{
		141	void *newptr = realloc (ptr, size);
		142
		143	if (newptr)
		144	return newptr;
		145
		146	sleep (60);
		147	}
		148	}
		149
		150	...
		151	ev_set_allocator (persistent_realloc);
89		152
90	=item ev_set_syserr_cb (void (cb)(const char msg));	153	=item ev_set_syserr_cb (void (cb)(const char msg));
91		154
92	Set the callback function to call on a retryable syscall error (such	155	Set the callback function to call on a retryable syscall error (such
93	as failed select, poll, epoll_wait). The message is a printable string	156	as failed select, poll, epoll_wait). The message is a printable string
…		…
95	callback is set, then libev will expect it to remedy the sitution, no	158	callback is set, then libev will expect it to remedy the sitution, no
96	matter what, when it returns. That is, libev will generally retry the	159	matter what, when it returns. That is, libev will generally retry the
97	requested operation, or, if the condition doesn't go away, do bad stuff	160	requested operation, or, if the condition doesn't go away, do bad stuff
98	(such as abort).	161	(such as abort).
99		162
		163	Example: do the same thing as libev does internally:
		164
		165	static void
		166	fatal_error (const char *msg)
		167	{
		168	perror (msg);
		169	abort ();
		170	}
		171
		172	...
		173	ev_set_syserr_cb (fatal_error);
		174
100	=back	175	=back
101		176
102	=head1 FUNCTIONS CONTROLLING THE EVENT LOOP	177	=head1 FUNCTIONS CONTROLLING THE EVENT LOOP
103		178
104	An event loop is described by a C<struct ev_loop *>. The library knows two	179	An event loop is described by a C<struct ev_loop *>. The library knows two
…		…
117	=item struct ev_loop *ev_default_loop (unsigned int flags)	192	=item struct ev_loop *ev_default_loop (unsigned int flags)
118		193
119	This will initialise the default event loop if it hasn't been initialised	194	This will initialise the default event loop if it hasn't been initialised
120	yet and return it. If the default loop could not be initialised, returns	195	yet and return it. If the default loop could not be initialised, returns
121	false. If it already was initialised it simply returns it (and ignores the	196	false. If it already was initialised it simply returns it (and ignores the
122	flags).	197	flags. If that is troubling you, check C<ev_backend ()> afterwards).
123		198
124	If you don't know what event loop to use, use the one returned from this	199	If you don't know what event loop to use, use the one returned from this
125	function.	200	function.
126		201
127	The flags argument can be used to specify special behaviour or specific	202	The flags argument can be used to specify special behaviour or specific
128	backends to use, and is usually specified as 0 (or EVFLAG_AUTO).	203	backends to use, and is usually specified as C<0> (or C<EVFLAG_AUTO>).
129		204
130	It supports the following flags:	205	The following flags are supported:
131		206
132	=over 4	207	=over 4
133		208
134	=item C<EVFLAG_AUTO>	209	=item C<EVFLAG_AUTO>
135		210
…		…
143	C<LIBEV_FLAGS>. Otherwise (the default), this environment variable will	218	C<LIBEV_FLAGS>. Otherwise (the default), this environment variable will
144	override the flags completely if it is found in the environment. This is	219	override the flags completely if it is found in the environment. This is
145	useful to try out specific backends to test their performance, or to work	220	useful to try out specific backends to test their performance, or to work
146	around bugs.	221	around bugs.
147		222
148	=item C<EVMETHOD_SELECT> (portable select backend)	223	=item C<EVBACKEND_SELECT> (value 1, portable select backend)
149		224
		225	This is your standard select(2) backend. Not I<completely> standard, as
		226	libev tries to roll its own fd_set with no limits on the number of fds,
		227	but if that fails, expect a fairly low limit on the number of fds when
		228	using this backend. It doesn't scale too well (O(highest_fd)), but its usually
		229	the fastest backend for a low number of fds.
		230
150	=item C<EVMETHOD_POLL> (poll backend, available everywhere except on windows)	231	=item C<EVBACKEND_POLL> (value 2, poll backend, available everywhere except on windows)
151		232
152	=item C<EVMETHOD_EPOLL> (linux only)	233	And this is your standard poll(2) backend. It's more complicated than
		234	select, but handles sparse fds better and has no artificial limit on the
		235	number of fds you can use (except it will slow down considerably with a
		236	lot of inactive fds). It scales similarly to select, i.e. O(total_fds).
153		237
154	=item C<EVMETHOD_KQUEUE> (some bsds only)	238	=item C<EVBACKEND_EPOLL> (value 4, Linux)
155		239
156	=item C<EVMETHOD_DEVPOLL> (solaris 8 only)	240	For few fds, this backend is a bit little slower than poll and select,
		241	but it scales phenomenally better. While poll and select usually scale like
		242	O(total_fds) where n is the total number of fds (or the highest fd), epoll scales
		243	either O(1) or O(active_fds).
157		244
158	=item C<EVMETHOD_PORT> (solaris 10 only)	245	While stopping and starting an I/O watcher in the same iteration will
		246	result in some caching, there is still a syscall per such incident
		247	(because the fd could point to a different file description now), so its
		248	best to avoid that. Also, dup()ed file descriptors might not work very
		249	well if you register events for both fds.
		250
		251	Please note that epoll sometimes generates spurious notifications, so you
		252	need to use non-blocking I/O or other means to avoid blocking when no data
		253	(or space) is available.
		254
		255	=item C<EVBACKEND_KQUEUE> (value 8, most BSD clones)
		256
		257	Kqueue deserves special mention, as at the time of this writing, it
		258	was broken on all BSDs except NetBSD (usually it doesn't work with
		259	anything but sockets and pipes, except on Darwin, where of course its
		260	completely useless). For this reason its not being "autodetected"
		261	unless you explicitly specify it explicitly in the flags (i.e. using
		262	C<EVBACKEND_KQUEUE>).
		263
		264	It scales in the same way as the epoll backend, but the interface to the
		265	kernel is more efficient (which says nothing about its actual speed, of
		266	course). While starting and stopping an I/O watcher does not cause an
		267	extra syscall as with epoll, it still adds up to four event changes per
		268	incident, so its best to avoid that.
		269
		270	=item C<EVBACKEND_DEVPOLL> (value 16, Solaris 8)
		271
		272	This is not implemented yet (and might never be).
		273
		274	=item C<EVBACKEND_PORT> (value 32, Solaris 10)
		275
		276	This uses the Solaris 10 port mechanism. As with everything on Solaris,
		277	it's really slow, but it still scales very well (O(active_fds)).
		278
		279	Please note that solaris ports can result in a lot of spurious
		280	notifications, so you need to use non-blocking I/O or other means to avoid
		281	blocking when no data (or space) is available.
		282
		283	=item C<EVBACKEND_ALL>
		284
		285	Try all backends (even potentially broken ones that wouldn't be tried
		286	with C<EVFLAG_AUTO>). Since this is a mask, you can do stuff such as
		287	C<EVBACKEND_ALL & ~EVBACKEND_KQUEUE>.
		288
		289	=back
159		290
160	If one or more of these are ored into the flags value, then only these	291	If one or more of these are ored into the flags value, then only these
161	backends will be tried (in the reverse order as given here). If one are	292	backends will be tried (in the reverse order as given here). If none are
162	specified, any backend will do.	293	specified, most compiled-in backend will be tried, usually in reverse
		294	order of their flag values :)
163		295
164	=back	296	The most typical usage is like this:
		297
		298	if (!ev_default_loop (0))
		299	fatal ("could not initialise libev, bad $LIBEV_FLAGS in environment?");
		300
		301	Restrict libev to the select and poll backends, and do not allow
		302	environment settings to be taken into account:
		303
		304	ev_default_loop (EVBACKEND_POLL \| EVBACKEND_SELECT \| EVFLAG_NOENV);
		305
		306	Use whatever libev has to offer, but make sure that kqueue is used if
		307	available (warning, breaks stuff, best use only with your own private
		308	event loop and only if you know the OS supports your types of fds):
		309
		310	ev_default_loop (ev_recommended_backends () \| EVBACKEND_KQUEUE);
165		311
166	=item struct ev_loop *ev_loop_new (unsigned int flags)	312	=item struct ev_loop *ev_loop_new (unsigned int flags)
167		313
168	Similar to C<ev_default_loop>, but always creates a new event loop that is	314	Similar to C<ev_default_loop>, but always creates a new event loop that is
169	always distinct from the default loop. Unlike the default loop, it cannot	315	always distinct from the default loop. Unlike the default loop, it cannot
170	handle signal and child watchers, and attempts to do so will be greeted by	316	handle signal and child watchers, and attempts to do so will be greeted by
171	undefined behaviour (or a failed assertion if assertions are enabled).	317	undefined behaviour (or a failed assertion if assertions are enabled).
172		318
		319	Example: try to create a event loop that uses epoll and nothing else.
		320
		321	struct ev_loop *epoller = ev_loop_new (EVBACKEND_EPOLL \| EVFLAG_NOENV);
		322	if (!epoller)
		323	fatal ("no epoll found here, maybe it hides under your chair");
		324
173	=item ev_default_destroy ()	325	=item ev_default_destroy ()
174		326
175	Destroys the default loop again (frees all memory and kernel state	327	Destroys the default loop again (frees all memory and kernel state
176	etc.). This stops all registered event watchers (by not touching them in	328	etc.). None of the active event watchers will be stopped in the normal
177	any way whatsoever, although you cannot rely on this :).	329	sense, so e.g. C<ev_is_active> might still return true. It is your
		330	responsibility to either stop all watchers cleanly yoursef I<before>
		331	calling this function, or cope with the fact afterwards (which is usually
		332	the easiest thing, youc na just ignore the watchers and/or C<free ()> them
		333	for example).
178		334
179	=item ev_loop_destroy (loop)	335	=item ev_loop_destroy (loop)
180		336
181	Like C<ev_default_destroy>, but destroys an event loop created by an	337	Like C<ev_default_destroy>, but destroys an event loop created by an
182	earlier call to C<ev_loop_new>.	338	earlier call to C<ev_loop_new>.
…		…
186	This function reinitialises the kernel state for backends that have	342	This function reinitialises the kernel state for backends that have
187	one. Despite the name, you can call it anytime, but it makes most sense	343	one. Despite the name, you can call it anytime, but it makes most sense
188	after forking, in either the parent or child process (or both, but that	344	after forking, in either the parent or child process (or both, but that
189	again makes little sense).	345	again makes little sense).
190		346
191	You I<must> call this function after forking if and only if you want to	347	You I<must> call this function in the child process after forking if and
192	use the event library in both processes. If you just fork+exec, you don't	348	only if you want to use the event library in both processes. If you just
193	have to call it.	349	fork+exec, you don't have to call it.
194		350
195	The function itself is quite fast and it's usually not a problem to call	351	The function itself is quite fast and it's usually not a problem to call
196	it just in case after a fork. To make this easy, the function will fit in	352	it just in case after a fork. To make this easy, the function will fit in
197	quite nicely into a call to C<pthread_atfork>:	353	quite nicely into a call to C<pthread_atfork>:
198		354
199	pthread_atfork (0, 0, ev_default_fork);	355	pthread_atfork (0, 0, ev_default_fork);
200		356
		357	At the moment, C<EVBACKEND_SELECT> and C<EVBACKEND_POLL> are safe to use
		358	without calling this function, so if you force one of those backends you
		359	do not need to care.
		360
201	=item ev_loop_fork (loop)	361	=item ev_loop_fork (loop)
202		362
203	Like C<ev_default_fork>, but acts on an event loop created by	363	Like C<ev_default_fork>, but acts on an event loop created by
204	C<ev_loop_new>. Yes, you have to call this on every allocated event loop	364	C<ev_loop_new>. Yes, you have to call this on every allocated event loop
205	after fork, and how you do this is entirely your own problem.	365	after fork, and how you do this is entirely your own problem.
206		366
207	=item unsigned int ev_method (loop)	367	=item unsigned int ev_backend (loop)
208		368
209	Returns one of the C<EVMETHOD_*> flags indicating the event backend in	369	Returns one of the C<EVBACKEND_*> flags indicating the event backend in
210	use.	370	use.
211		371
212	=item ev_tstamp ev_now (loop)	372	=item ev_tstamp ev_now (loop)
213		373
214	Returns the current "event loop time", which is the time the event loop	374	Returns the current "event loop time", which is the time the event loop
215	got events and started processing them. This timestamp does not change	375	received events and started processing them. This timestamp does not
216	as long as callbacks are being processed, and this is also the base time	376	change as long as callbacks are being processed, and this is also the base
217	used for relative timers. You can treat it as the timestamp of the event	377	time used for relative timers. You can treat it as the timestamp of the
218	occuring (or more correctly, the mainloop finding out about it).	378	event occuring (or more correctly, libev finding out about it).
219		379
220	=item ev_loop (loop, int flags)	380	=item ev_loop (loop, int flags)
221		381
222	Finally, this is it, the event handler. This function usually is called	382	Finally, this is it, the event handler. This function usually is called
223	after you initialised all your watchers and you want to start handling	383	after you initialised all your watchers and you want to start handling
224	events.	384	events.
225		385
226	If the flags argument is specified as 0, it will not return until either	386	If the flags argument is specified as C<0>, it will not return until
227	no event watchers are active anymore or C<ev_unloop> was called.	387	either no event watchers are active anymore or C<ev_unloop> was called.
		388
		389	Please note that an explicit C<ev_unloop> is usually better than
		390	relying on all watchers to be stopped when deciding when a program has
		391	finished (especially in interactive programs), but having a program that
		392	automatically loops as long as it has to and no longer by virtue of
		393	relying on its watchers stopping correctly is a thing of beauty.
228		394
229	A flags value of C<EVLOOP_NONBLOCK> will look for new events, will handle	395	A flags value of C<EVLOOP_NONBLOCK> will look for new events, will handle
230	those events and any outstanding ones, but will not block your process in	396	those events and any outstanding ones, but will not block your process in
231	case there are no events and will return after one iteration of the loop.	397	case there are no events and will return after one iteration of the loop.
232		398
233	A flags value of C<EVLOOP_ONESHOT> will look for new events (waiting if	399	A flags value of C<EVLOOP_ONESHOT> will look for new events (waiting if
234	neccessary) and will handle those and any outstanding ones. It will block	400	neccessary) and will handle those and any outstanding ones. It will block
235	your process until at least one new event arrives, and will return after	401	your process until at least one new event arrives, and will return after
236	one iteration of the loop.	402	one iteration of the loop. This is useful if you are waiting for some
		403	external event in conjunction with something not expressible using other
		404	libev watchers. However, a pair of C<ev_prepare>/C<ev_check> watchers is
		405	usually a better approach for this kind of thing.
237		406
238	This flags value could be used to implement alternative looping	407	Here are the gory details of what C<ev_loop> does:
239	constructs, but the C<prepare> and C<check> watchers provide a better and	408
240	more generic mechanism.	409	* If there are no active watchers (reference count is zero), return.
		410	- Queue prepare watchers and then call all outstanding watchers.
		411	- If we have been forked, recreate the kernel state.
		412	- Update the kernel state with all outstanding changes.
		413	- Update the "event loop time".
		414	- Calculate for how long to block.
		415	- Block the process, waiting for any events.
		416	- Queue all outstanding I/O (fd) events.
		417	- Update the "event loop time" and do time jump handling.
		418	- Queue all outstanding timers.
		419	- Queue all outstanding periodics.
		420	- If no events are pending now, queue all idle watchers.
		421	- Queue all check watchers.
		422	- Call all queued watchers in reverse order (i.e. check watchers first).
		423	Signals and child watchers are implemented as I/O watchers, and will
		424	be handled here by queueing them when their watcher gets executed.
		425	- If ev_unloop has been called or EVLOOP_ONESHOT or EVLOOP_NONBLOCK
		426	were used, return, otherwise continue with step *.
		427
		428	Example: queue some jobs and then loop until no events are outsanding
		429	anymore.
		430
		431	... queue jobs here, make sure they register event watchers as long
		432	... as they still have work to do (even an idle watcher will do..)
		433	ev_loop (my_loop, 0);
		434	... jobs done. yeah!
241		435
242	=item ev_unloop (loop, how)	436	=item ev_unloop (loop, how)
243		437
244	Can be used to make a call to C<ev_loop> return early (but only after it	438	Can be used to make a call to C<ev_loop> return early (but only after it
245	has processed all outstanding events). The C<how> argument must be either	439	has processed all outstanding events). The C<how> argument must be either
246	C<EVUNLOOP_ONCE>, which will make the innermost C<ev_loop> call return, or	440	C<EVUNLOOP_ONE>, which will make the innermost C<ev_loop> call return, or
247	C<EVUNLOOP_ALL>, which will make all nested C<ev_loop> calls return.	441	C<EVUNLOOP_ALL>, which will make all nested C<ev_loop> calls return.
248		442
249	=item ev_ref (loop)	443	=item ev_ref (loop)
250		444
251	=item ev_unref (loop)	445	=item ev_unref (loop)
…		…
259	visible to the libev user and should not keep C<ev_loop> from exiting if	453	visible to the libev user and should not keep C<ev_loop> from exiting if
260	no event watchers registered by it are active. It is also an excellent	454	no event watchers registered by it are active. It is also an excellent
261	way to do this for generic recurring timers or from within third-party	455	way to do this for generic recurring timers or from within third-party
262	libraries. Just remember to I<unref after start> and I<ref before stop>.	456	libraries. Just remember to I<unref after start> and I<ref before stop>.
263		457
		458	Example: create a signal watcher, but keep it from keeping C<ev_loop>
		459	running when nothing else is active.
		460
		461	struct dv_signal exitsig;
		462	ev_signal_init (&exitsig, sig_cb, SIGINT);
		463	ev_signal_start (myloop, &exitsig);
		464	evf_unref (myloop);
		465
		466	Example: for some weird reason, unregister the above signal handler again.
		467
		468	ev_ref (myloop);
		469	ev_signal_stop (myloop, &exitsig);
		470
264	=back	471	=back
265		472
266	=head1 ANATOMY OF A WATCHER	473	=head1 ANATOMY OF A WATCHER
267		474
268	A watcher is a structure that you create and register to record your	475	A watcher is a structure that you create and register to record your
…		…
302	*) >>), and you can stop watching for events at any time by calling the	509	*) >>), and you can stop watching for events at any time by calling the
303	corresponding stop function (C<< ev_<type>_stop (loop, watcher *) >>.	510	corresponding stop function (C<< ev_<type>_stop (loop, watcher *) >>.
304		511
305	As long as your watcher is active (has been started but not stopped) you	512	As long as your watcher is active (has been started but not stopped) you
306	must not touch the values stored in it. Most specifically you must never	513	must not touch the values stored in it. Most specifically you must never
307	reinitialise it or call its set method.	514	reinitialise it or call its C<set> macro.
308
309	You can check whether an event is active by calling the C<ev_is_active
310	(watcher *)> macro. To see whether an event is outstanding (but the
311	callback for it has not been called yet) you can use the C<ev_is_pending
312	(watcher *)> macro.
313		515
314	Each and every callback receives the event loop pointer as first, the	516	Each and every callback receives the event loop pointer as first, the
315	registered watcher structure as second, and a bitset of received events as	517	registered watcher structure as second, and a bitset of received events as
316	third argument.	518	third argument.
317		519
…		…
374	with the error from read() or write(). This will not work in multithreaded	576	with the error from read() or write(). This will not work in multithreaded
375	programs, though, so beware.	577	programs, though, so beware.
376		578
377	=back	579	=back
378		580
		581	=head2 SUMMARY OF GENERIC WATCHER FUNCTIONS
		582
		583	In the following description, C<TYPE> stands for the watcher type,
		584	e.g. C<timer> for C<ev_timer> watchers and C<io> for C<ev_io> watchers.
		585
		586	=over 4
		587
		588	=item C<ev_init> (ev_TYPE *watcher, callback)
		589
		590	This macro initialises the generic portion of a watcher. The contents
		591	of the watcher object can be arbitrary (so C<malloc> will do). Only
		592	the generic parts of the watcher are initialised, you I<need> to call
		593	the type-specific C<ev_TYPE_set> macro afterwards to initialise the
		594	type-specific parts. For each type there is also a C<ev_TYPE_init> macro
		595	which rolls both calls into one.
		596
		597	You can reinitialise a watcher at any time as long as it has been stopped
		598	(or never started) and there are no pending events outstanding.
		599
		600	The callbakc is always of type C<void ()(ev_loop loop, ev_TYPE *watcher,
		601	int revents)>.
		602
		603	=item C<ev_TYPE_set> (ev_TYPE *, [args])
		604
		605	This macro initialises the type-specific parts of a watcher. You need to
		606	call C<ev_init> at least once before you call this macro, but you can
		607	call C<ev_TYPE_set> any number of times. You must not, however, call this
		608	macro on a watcher that is active (it can be pending, however, which is a
		609	difference to the C<ev_init> macro).
		610
		611	Although some watcher types do not have type-specific arguments
		612	(e.g. C<ev_prepare>) you still need to call its C<set> macro.
		613
		614	=item C<ev_TYPE_init> (ev_TYPE *watcher, callback, [args])
		615
		616	This convinience macro rolls both C<ev_init> and C<ev_TYPE_set> macro
		617	calls into a single call. This is the most convinient method to initialise
		618	a watcher. The same limitations apply, of course.
		619
		620	=item C<ev_TYPE_start> (loop , ev_TYPE watcher)
		621
		622	Starts (activates) the given watcher. Only active watchers will receive
		623	events. If the watcher is already active nothing will happen.
		624
		625	=item C<ev_TYPE_stop> (loop , ev_TYPE watcher)
		626
		627	Stops the given watcher again (if active) and clears the pending
		628	status. It is possible that stopped watchers are pending (for example,
		629	non-repeating timers are being stopped when they become pending), but
		630	C<ev_TYPE_stop> ensures that the watcher is neither active nor pending. If
		631	you want to free or reuse the memory used by the watcher it is therefore a
		632	good idea to always call its C<ev_TYPE_stop> function.
		633
		634	=item bool ev_is_active (ev_TYPE *watcher)
		635
		636	Returns a true value iff the watcher is active (i.e. it has been started
		637	and not yet been stopped). As long as a watcher is active you must not modify
		638	it.
		639
		640	=item bool ev_is_pending (ev_TYPE *watcher)
		641
		642	Returns a true value iff the watcher is pending, (i.e. it has outstanding
		643	events but its callback has not yet been invoked). As long as a watcher
		644	is pending (but not active) you must not call an init function on it (but
		645	C<ev_TYPE_set> is safe) and you must make sure the watcher is available to
		646	libev (e.g. you cnanot C<free ()> it).
		647
		648	=item callback = ev_cb (ev_TYPE *watcher)
		649
		650	Returns the callback currently set on the watcher.
		651
		652	=item ev_cb_set (ev_TYPE *watcher, callback)
		653
		654	Change the callback. You can change the callback at virtually any time
		655	(modulo threads).
		656
		657	=back
		658
		659
379	=head2 ASSOCIATING CUSTOM DATA WITH A WATCHER	660	=head2 ASSOCIATING CUSTOM DATA WITH A WATCHER
380		661
381	Each watcher has, by default, a member C<void *data> that you can change	662	Each watcher has, by default, a member C<void *data> that you can change
382	and read at any time, libev will completely ignore it. This can be used	663	and read at any time, libev will completely ignore it. This can be used
383	to associate arbitrary data with your watcher. If you need more data and	664	to associate arbitrary data with your watcher. If you need more data and
…		…
409	=head1 WATCHER TYPES	690	=head1 WATCHER TYPES
410		691
411	This section describes each watcher in detail, but will not repeat	692	This section describes each watcher in detail, but will not repeat
412	information given in the last section.	693	information given in the last section.
413		694
		695
414	=head2 C<ev_io> - is this file descriptor readable or writable	696	=head2 C<ev_io> - is this file descriptor readable or writable
415		697
416	I/O watchers check whether a file descriptor is readable or writable	698	I/O watchers check whether a file descriptor is readable or writable
417	in each iteration of the event loop (This behaviour is called	699	in each iteration of the event loop (This behaviour is called
418	level-triggering because you keep receiving events as long as the	700	level-triggering because you keep receiving events as long as the
…		…
425	required if you know what you are doing).	707	required if you know what you are doing).
426		708
427	You have to be careful with dup'ed file descriptors, though. Some backends	709	You have to be careful with dup'ed file descriptors, though. Some backends
428	(the linux epoll backend is a notable example) cannot handle dup'ed file	710	(the linux epoll backend is a notable example) cannot handle dup'ed file
429	descriptors correctly if you register interest in two or more fds pointing	711	descriptors correctly if you register interest in two or more fds pointing
430	to the same file/socket etc. description (that is, they share the same	712	to the same underlying file/socket etc. description (that is, they share
431	underlying "file open").	713	the same underlying "file open").
432		714
433	If you must do this, then force the use of a known-to-be-good backend	715	If you must do this, then force the use of a known-to-be-good backend
434	(at the time of this writing, this includes only EVMETHOD_SELECT and	716	(at the time of this writing, this includes only C<EVBACKEND_SELECT> and
435	EVMETHOD_POLL).	717	C<EVBACKEND_POLL>).
436		718
437	=over 4	719	=over 4
438		720
439	=item ev_io_init (ev_io *, callback, int fd, int events)	721	=item ev_io_init (ev_io *, callback, int fd, int events)
440		722
…		…
442		724
443	Configures an C<ev_io> watcher. The fd is the file descriptor to rceeive	725	Configures an C<ev_io> watcher. The fd is the file descriptor to rceeive
444	events for and events is either C<EV_READ>, C<EV_WRITE> or C<EV_READ \|	726	events for and events is either C<EV_READ>, C<EV_WRITE> or C<EV_READ \|
445	EV_WRITE> to receive the given events.	727	EV_WRITE> to receive the given events.
446		728
		729	Please note that most of the more scalable backend mechanisms (for example
		730	epoll and solaris ports) can result in spurious readyness notifications
		731	for file descriptors, so you practically need to use non-blocking I/O (and
		732	treat callback invocation as hint only), or retest separately with a safe
		733	interface before doing I/O (XLib can do this), or force the use of either
		734	C<EVBACKEND_SELECT> or C<EVBACKEND_POLL>, which don't suffer from this
		735	problem. Also note that it is quite easy to have your callback invoked
		736	when the readyness condition is no longer valid even when employing
		737	typical ways of handling events, so its a good idea to use non-blocking
		738	I/O unconditionally.
		739
447	=back	740	=back
		741
		742	Example: call C<stdin_readable_cb> when STDIN_FILENO has become, well
		743	readable, but only once. Since it is likely line-buffered, you could
		744	attempt to read a whole line in the callback:
		745
		746	static void
		747	stdin_readable_cb (struct ev_loop loop, struct ev_io w, int revents)
		748	{
		749	ev_io_stop (loop, w);
		750	.. read from stdin here (or from w->fd) and haqndle any I/O errors
		751	}
		752
		753	...
		754	struct ev_loop *loop = ev_default_init (0);
		755	struct ev_io stdin_readable;
		756	ev_io_init (&stdin_readable, stdin_readable_cb, STDIN_FILENO, EV_READ);
		757	ev_io_start (loop, &stdin_readable);
		758	ev_loop (loop, 0);
		759
448		760
449	=head2 C<ev_timer> - relative and optionally recurring timeouts	761	=head2 C<ev_timer> - relative and optionally recurring timeouts
450		762
451	Timer watchers are simple relative timers that generate an event after a	763	Timer watchers are simple relative timers that generate an event after a
452	given time, and optionally repeating in regular intervals after that.	764	given time, and optionally repeating in regular intervals after that.
453		765
454	The timers are based on real time, that is, if you register an event that	766	The timers are based on real time, that is, if you register an event that
455	times out after an hour and you reset your system clock to last years	767	times out after an hour and you reset your system clock to last years
456	time, it will still time out after (roughly) and hour. "Roughly" because	768	time, it will still time out after (roughly) and hour. "Roughly" because
457	detecting time jumps is hard, and soem inaccuracies are unavoidable (the	769	detecting time jumps is hard, and some inaccuracies are unavoidable (the
458	monotonic clock option helps a lot here).	770	monotonic clock option helps a lot here).
459		771
460	The relative timeouts are calculated relative to the C<ev_now ()>	772	The relative timeouts are calculated relative to the C<ev_now ()>
461	time. This is usually the right thing as this timestamp refers to the time	773	time. This is usually the right thing as this timestamp refers to the time
462	of the event triggering whatever timeout you are modifying/starting. If	774	of the event triggering whatever timeout you are modifying/starting. If
463	you suspect event processing to be delayed and you need to base the timeout	775	you suspect event processing to be delayed and you I<need> to base the timeout
464	on the current time, use something like this to adjust for this:	776	on the current time, use something like this to adjust for this:
465		777
466	ev_timer_set (&timer, after + ev_now () - ev_time (), 0.);	778	ev_timer_set (&timer, after + ev_now () - ev_time (), 0.);
		779
		780	The callback is guarenteed to be invoked only when its timeout has passed,
		781	but if multiple timers become ready during the same loop iteration then
		782	order of execution is undefined.
467		783
468	=over 4	784	=over 4
469		785
470	=item ev_timer_init (ev_timer *, callback, ev_tstamp after, ev_tstamp repeat)	786	=item ev_timer_init (ev_timer *, callback, ev_tstamp after, ev_tstamp repeat)
471		787
…		…
501	state where you do not expect data to travel on the socket, you can stop	817	state where you do not expect data to travel on the socket, you can stop
502	the timer, and again will automatically restart it if need be.	818	the timer, and again will automatically restart it if need be.
503		819
504	=back	820	=back
505		821
		822	Example: create a timer that fires after 60 seconds.
		823
		824	static void
		825	one_minute_cb (struct ev_loop loop, struct ev_timer w, int revents)
		826	{
		827	.. one minute over, w is actually stopped right here
		828	}
		829
		830	struct ev_timer mytimer;
		831	ev_timer_init (&mytimer, one_minute_cb, 60., 0.);
		832	ev_timer_start (loop, &mytimer);
		833
		834	Example: create a timeout timer that times out after 10 seconds of
		835	inactivity.
		836
		837	static void
		838	timeout_cb (struct ev_loop loop, struct ev_timer w, int revents)
		839	{
		840	.. ten seconds without any activity
		841	}
		842
		843	struct ev_timer mytimer;
		844	ev_timer_init (&mytimer, timeout_cb, 0., 10.); /* note, only repeat used */
		845	ev_timer_again (&mytimer); /* start timer */
		846	ev_loop (loop, 0);
		847
		848	// and in some piece of code that gets executed on any "activity":
		849	// reset the timeout to start ticking again at 10 seconds
		850	ev_timer_again (&mytimer);
		851
		852
506	=head2 C<ev_periodic> - to cron or not to cron	853	=head2 C<ev_periodic> - to cron or not to cron
507		854
508	Periodic watchers are also timers of a kind, but they are very versatile	855	Periodic watchers are also timers of a kind, but they are very versatile
509	(and unfortunately a bit complex).	856	(and unfortunately a bit complex).
510		857
…		…
518	again).	865	again).
519		866
520	They can also be used to implement vastly more complex timers, such as	867	They can also be used to implement vastly more complex timers, such as
521	triggering an event on eahc midnight, local time.	868	triggering an event on eahc midnight, local time.
522		869
		870	As with timers, the callback is guarenteed to be invoked only when the
		871	time (C<at>) has been passed, but if multiple periodic timers become ready
		872	during the same loop iteration then order of execution is undefined.
		873
523	=over 4	874	=over 4
524		875
525	=item ev_periodic_init (ev_periodic *, callback, ev_tstamp at, ev_tstamp interval, reschedule_cb)	876	=item ev_periodic_init (ev_periodic *, callback, ev_tstamp at, ev_tstamp interval, reschedule_cb)
526		877
527	=item ev_periodic_set (ev_periodic *, ev_tstamp after, ev_tstamp repeat, reschedule_cb)	878	=item ev_periodic_set (ev_periodic *, ev_tstamp after, ev_tstamp repeat, reschedule_cb)
528		879
529	Lots of arguments, lets sort it out... There are basically three modes of	880	Lots of arguments, lets sort it out... There are basically three modes of
530	operation, and we will explain them from simplest to complex:	881	operation, and we will explain them from simplest to complex:
531
532		882
533	=over 4	883	=over 4
534		884
535	=item * absolute timer (interval = reschedule_cb = 0)	885	=item * absolute timer (interval = reschedule_cb = 0)
536		886
…		…
601	when you changed some parameters or the reschedule callback would return	951	when you changed some parameters or the reschedule callback would return
602	a different time than the last time it was called (e.g. in a crond like	952	a different time than the last time it was called (e.g. in a crond like
603	program when the crontabs have changed).	953	program when the crontabs have changed).
604		954
605	=back	955	=back
		956
		957	Example: call a callback every hour, or, more precisely, whenever the
		958	system clock is divisible by 3600. The callback invocation times have
		959	potentially a lot of jittering, but good long-term stability.
		960
		961	static void
		962	clock_cb (struct ev_loop loop, struct ev_io w, int revents)
		963	{
		964	... its now a full hour (UTC, or TAI or whatever your clock follows)
		965	}
		966
		967	struct ev_periodic hourly_tick;
		968	ev_periodic_init (&hourly_tick, clock_cb, 0., 3600., 0);
		969	ev_periodic_start (loop, &hourly_tick);
		970
		971	Example: the same as above, but use a reschedule callback to do it:
		972
		973	#include <math.h>
		974
		975	static ev_tstamp
		976	my_scheduler_cb (struct ev_periodic *w, ev_tstamp now)
		977	{
		978	return fmod (now, 3600.) + 3600.;
		979	}
		980
		981	ev_periodic_init (&hourly_tick, clock_cb, 0., 0., my_scheduler_cb);
		982
		983	Example: call a callback every hour, starting now:
		984
		985	struct ev_periodic hourly_tick;
		986	ev_periodic_init (&hourly_tick, clock_cb,
		987	fmod (ev_now (loop), 3600.), 3600., 0);
		988	ev_periodic_start (loop, &hourly_tick);
		989
606		990
607	=head2 C<ev_signal> - signal me when a signal gets signalled	991	=head2 C<ev_signal> - signal me when a signal gets signalled
608		992
609	Signal watchers will trigger an event when the process receives a specific	993	Signal watchers will trigger an event when the process receives a specific
610	signal one or more times. Even though signals are very asynchronous, libev	994	signal one or more times. Even though signals are very asynchronous, libev
…		…
627	Configures the watcher to trigger on the given signal number (usually one	1011	Configures the watcher to trigger on the given signal number (usually one
628	of the C<SIGxxx> constants).	1012	of the C<SIGxxx> constants).
629		1013
630	=back	1014	=back
631		1015
		1016
632	=head2 C<ev_child> - wait for pid status changes	1017	=head2 C<ev_child> - wait for pid status changes
633		1018
634	Child watchers trigger when your process receives a SIGCHLD in response to	1019	Child watchers trigger when your process receives a SIGCHLD in response to
635	some child status changes (most typically when a child of yours dies).	1020	some child status changes (most typically when a child of yours dies).
636		1021
…		…
646	the status word (use the macros from C<sys/wait.h> and see your systems	1031	the status word (use the macros from C<sys/wait.h> and see your systems
647	C<waitpid> documentation). The C<rpid> member contains the pid of the	1032	C<waitpid> documentation). The C<rpid> member contains the pid of the
648	process causing the status change.	1033	process causing the status change.
649		1034
650	=back	1035	=back
		1036
		1037	Example: try to exit cleanly on SIGINT and SIGTERM.
		1038
		1039	static void
		1040	sigint_cb (struct ev_loop loop, struct ev_signal w, int revents)
		1041	{
		1042	ev_unloop (loop, EVUNLOOP_ALL);
		1043	}
		1044
		1045	struct ev_signal signal_watcher;
		1046	ev_signal_init (&signal_watcher, sigint_cb, SIGINT);
		1047	ev_signal_start (loop, &sigint_cb);
		1048
651		1049
652	=head2 C<ev_idle> - when you've got nothing better to do	1050	=head2 C<ev_idle> - when you've got nothing better to do
653		1051
654	Idle watchers trigger events when there are no other events are pending	1052	Idle watchers trigger events when there are no other events are pending
655	(prepare, check and other idle watchers do not count). That is, as long	1053	(prepare, check and other idle watchers do not count). That is, as long
…		…
675	kind. There is a C<ev_idle_set> macro, but using it is utterly pointless,	1073	kind. There is a C<ev_idle_set> macro, but using it is utterly pointless,
676	believe me.	1074	believe me.
677		1075
678	=back	1076	=back
679		1077
		1078	Example: dynamically allocate an C<ev_idle>, start it, and in the
		1079	callback, free it. Alos, use no error checking, as usual.
		1080
		1081	static void
		1082	idle_cb (struct ev_loop loop, struct ev_idle w, int revents)
		1083	{
		1084	free (w);
		1085	// now do something you wanted to do when the program has
		1086	// no longer asnything immediate to do.
		1087	}
		1088
		1089	struct ev_idle *idle_watcher = malloc (sizeof (struct ev_idle));
		1090	ev_idle_init (idle_watcher, idle_cb);
		1091	ev_idle_start (loop, idle_cb);
		1092
		1093
680	=head2 C<ev_prepare> and C<ev_check> - customise your event loop	1094	=head2 C<ev_prepare> and C<ev_check> - customise your event loop
681		1095
682	Prepare and check watchers are usually (but not always) used in tandem:	1096	Prepare and check watchers are usually (but not always) used in tandem:
683	prepare watchers get invoked before the process blocks and check watchers	1097	prepare watchers get invoked before the process blocks and check watchers
684	afterwards.	1098	afterwards.
685		1099
686	Their main purpose is to integrate other event mechanisms into libev. This	1100	Their main purpose is to integrate other event mechanisms into libev and
687	could be used, for example, to track variable changes, implement your own	1101	their use is somewhat advanced. This could be used, for example, to track
688	watchers, integrate net-snmp or a coroutine library and lots more.	1102	variable changes, implement your own watchers, integrate net-snmp or a
		1103	coroutine library and lots more.
689		1104
690	This is done by examining in each prepare call which file descriptors need	1105	This is done by examining in each prepare call which file descriptors need
691	to be watched by the other library, registering C<ev_io> watchers for	1106	to be watched by the other library, registering C<ev_io> watchers for
692	them and starting an C<ev_timer> watcher for any timeouts (many libraries	1107	them and starting an C<ev_timer> watcher for any timeouts (many libraries
693	provide just this functionality). Then, in the check watcher you check for	1108	provide just this functionality). Then, in the check watcher you check for
…		…
715	parameters of any kind. There are C<ev_prepare_set> and C<ev_check_set>	1130	parameters of any kind. There are C<ev_prepare_set> and C<ev_check_set>
716	macros, but using them is utterly, utterly and completely pointless.	1131	macros, but using them is utterly, utterly and completely pointless.
717		1132
718	=back	1133	=back
719		1134
		1135	Example: TODO.
		1136
		1137
		1138	=head2 C<ev_embed> - when one backend isn't enough
		1139
		1140	This is a rather advanced watcher type that lets you embed one event loop
		1141	into another (currently only C<ev_io> events are supported in the embedded
		1142	loop, other types of watchers might be handled in a delayed or incorrect
		1143	fashion and must not be used).
		1144
		1145	There are primarily two reasons you would want that: work around bugs and
		1146	prioritise I/O.
		1147
		1148	As an example for a bug workaround, the kqueue backend might only support
		1149	sockets on some platform, so it is unusable as generic backend, but you
		1150	still want to make use of it because you have many sockets and it scales
		1151	so nicely. In this case, you would create a kqueue-based loop and embed it
		1152	into your default loop (which might use e.g. poll). Overall operation will
		1153	be a bit slower because first libev has to poll and then call kevent, but
		1154	at least you can use both at what they are best.
		1155
		1156	As for prioritising I/O: rarely you have the case where some fds have
		1157	to be watched and handled very quickly (with low latency), and even
		1158	priorities and idle watchers might have too much overhead. In this case
		1159	you would put all the high priority stuff in one loop and all the rest in
		1160	a second one, and embed the second one in the first.
		1161
		1162	As long as the watcher is active, the callback will be invoked every time
		1163	there might be events pending in the embedded loop. The callback must then
		1164	call C<ev_embed_sweep (mainloop, watcher)> to make a single sweep and invoke
		1165	their callbacks (you could also start an idle watcher to give the embedded
		1166	loop strictly lower priority for example). You can also set the callback
		1167	to C<0>, in which case the embed watcher will automatically execute the
		1168	embedded loop sweep.
		1169
		1170	As long as the watcher is started it will automatically handle events. The
		1171	callback will be invoked whenever some events have been handled. You can
		1172	set the callback to C<0> to avoid having to specify one if you are not
		1173	interested in that.
		1174
		1175	Also, there have not currently been made special provisions for forking:
		1176	when you fork, you not only have to call C<ev_loop_fork> on both loops,
		1177	but you will also have to stop and restart any C<ev_embed> watchers
		1178	yourself.
		1179
		1180	Unfortunately, not all backends are embeddable, only the ones returned by
		1181	C<ev_embeddable_backends> are, which, unfortunately, does not include any
		1182	portable one.
		1183
		1184	So when you want to use this feature you will always have to be prepared
		1185	that you cannot get an embeddable loop. The recommended way to get around
		1186	this is to have a separate variables for your embeddable loop, try to
		1187	create it, and if that fails, use the normal loop for everything:
		1188
		1189	struct ev_loop *loop_hi = ev_default_init (0);
		1190	struct ev_loop *loop_lo = 0;
		1191	struct ev_embed embed;
		1192
		1193	// see if there is a chance of getting one that works
		1194	// (remember that a flags value of 0 means autodetection)
		1195	loop_lo = ev_embeddable_backends () & ev_recommended_backends ()
		1196	? ev_loop_new (ev_embeddable_backends () & ev_recommended_backends ())
		1197	: 0;
		1198
		1199	// if we got one, then embed it, otherwise default to loop_hi
		1200	if (loop_lo)
		1201	{
		1202	ev_embed_init (&embed, 0, loop_lo);
		1203	ev_embed_start (loop_hi, &embed);
		1204	}
		1205	else
		1206	loop_lo = loop_hi;
		1207
		1208	=over 4
		1209
		1210	=item ev_embed_init (ev_embed , callback, struct ev_loop embedded_loop)
		1211
		1212	=item ev_embed_set (ev_embed , callback, struct ev_loop embedded_loop)
		1213
		1214	Configures the watcher to embed the given loop, which must be
		1215	embeddable. If the callback is C<0>, then C<ev_embed_sweep> will be
		1216	invoked automatically, otherwise it is the responsibility of the callback
		1217	to invoke it (it will continue to be called until the sweep has been done,
		1218	if you do not want thta, you need to temporarily stop the embed watcher).
		1219
		1220	=item ev_embed_sweep (loop, ev_embed *)
		1221
		1222	Make a single, non-blocking sweep over the embedded loop. This works
		1223	similarly to C<ev_loop (embedded_loop, EVLOOP_NONBLOCK)>, but in the most
		1224	apropriate way for embedded loops.
		1225
		1226	=back
		1227
		1228
720	=head1 OTHER FUNCTIONS	1229	=head1 OTHER FUNCTIONS
721		1230
722	There are some other functions of possible interest. Described. Here. Now.	1231	There are some other functions of possible interest. Described. Here. Now.
723		1232
724	=over 4	1233	=over 4
…		…
753	/* stdin might have data for us, joy! */;	1262	/* stdin might have data for us, joy! */;
754	}	1263	}
755		1264
756	ev_once (STDIN_FILENO, EV_READ, 10., stdin_ready, 0);	1265	ev_once (STDIN_FILENO, EV_READ, 10., stdin_ready, 0);
757		1266
758	=item ev_feed_event (loop, watcher, int events)	1267	=item ev_feed_event (ev_loop , watcher , int revents)
759		1268
760	Feeds the given event set into the event loop, as if the specified event	1269	Feeds the given event set into the event loop, as if the specified event
761	had happened for the specified watcher (which must be a pointer to an	1270	had happened for the specified watcher (which must be a pointer to an
762	initialised but not necessarily started event watcher).	1271	initialised but not necessarily started event watcher).
763		1272
764	=item ev_feed_fd_event (loop, int fd, int revents)	1273	=item ev_feed_fd_event (ev_loop *, int fd, int revents)
765		1274
766	Feed an event on the given fd, as if a file descriptor backend detected	1275	Feed an event on the given fd, as if a file descriptor backend detected
767	the given events it.	1276	the given events it.
768		1277
769	=item ev_feed_signal_event (loop, int signum)	1278	=item ev_feed_signal_event (ev_loop *loop, int signum)
770		1279
771	Feed an event as if the given signal occured (loop must be the default loop!).	1280	Feed an event as if the given signal occured (C<loop> must be the default
		1281	loop!).
772		1282
773	=back	1283	=back
		1284
774		1285
775	=head1 LIBEVENT EMULATION	1286	=head1 LIBEVENT EMULATION
776		1287
		1288	Libev offers a compatibility emulation layer for libevent. It cannot
		1289	emulate the internals of libevent, so here are some usage hints:
		1290
		1291	=over 4
		1292
		1293	=item * Use it by including <event.h>, as usual.
		1294
		1295	=item * The following members are fully supported: ev_base, ev_callback,
		1296	ev_arg, ev_fd, ev_res, ev_events.
		1297
		1298	=item * Avoid using ev_flags and the EVLIST_*-macros, while it is
		1299	maintained by libev, it does not work exactly the same way as in libevent (consider
		1300	it a private API).
		1301
		1302	=item * Priorities are not currently supported. Initialising priorities
		1303	will fail and all watchers will have the same priority, even though there
		1304	is an ev_pri field.
		1305
		1306	=item * Other members are not supported.
		1307
		1308	=item * The libev emulation is I<not> ABI compatible to libevent, you need
		1309	to use the libev header file and library.
		1310
		1311	=back
		1312
		1313	=head1 C++ SUPPORT
		1314
777	TBD.	1315	TBD.
778		1316
779	=head1 C++ SUPPORT
780
781	TBD.
782
783	=head1 AUTHOR	1317	=head1 AUTHOR
784		1318
785	Marc Lehmann <libev@schmorp.de>.	1319	Marc Lehmann <libev@schmorp.de>.
786		1320

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Comparing libev/ev.pod (file contents): Revision 1.23 by root, Mon Nov 12 18:40:21 2007 UTC vs. Revision 1.37 by root, Sat Nov 24 07:20:43 2007 UTC

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Comparing libev/ev.pod (file contents):
Revision 1.23 by root, Mon Nov 12 18:40:21 2007 UTC vs.
Revision 1.37 by root, Sat Nov 24 07:20:43 2007 UTC