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

Comparing libev/ev.pod (file contents):
Revision 1.318 by root, Fri Oct 22 09:40:22 2010 UTC vs.
Revision 1.322 by root, Sun Oct 24 17:58:41 2010 UTC

…		…
43		43
44	int	44	int
45	main (void)	45	main (void)
46	{	46	{
47	// use the default event loop unless you have special needs	47	// use the default event loop unless you have special needs
48	struct ev_loop *loop = ev_default_loop (0);	48	struct ev_loop *loop = EV_DEFAULT;
49		49
50	// initialise an io watcher, then start it	50	// initialise an io watcher, then start it
51	// this one will watch for stdin to become readable	51	// this one will watch for stdin to become readable
52	ev_io_init (&stdin_watcher, stdin_cb, /STDIN_FILENO/ 0, EV_READ);	52	ev_io_init (&stdin_watcher, stdin_cb, /STDIN_FILENO/ 0, EV_READ);
53	ev_io_start (loop, &stdin_watcher);	53	ev_io_start (loop, &stdin_watcher);
…		…
165		165
166	=item ev_tstamp ev_time ()	166	=item ev_tstamp ev_time ()
167		167
168	Returns the current time as libev would use it. Please note that the	168	Returns the current time as libev would use it. Please note that the
169	C<ev_now> function is usually faster and also often returns the timestamp	169	C<ev_now> function is usually faster and also often returns the timestamp
170	you actually want to know. Also interetsing is the combination of	170	you actually want to know. Also interesting is the combination of
171	C<ev_update_now> and C<ev_now>.	171	C<ev_update_now> and C<ev_now>.
172		172
173	=item ev_sleep (ev_tstamp interval)	173	=item ev_sleep (ev_tstamp interval)
174		174
175	Sleep for the given interval: The current thread will be blocked until	175	Sleep for the given interval: The current thread will be blocked until
…		…
193	as this indicates an incompatible change. Minor versions are usually	193	as this indicates an incompatible change. Minor versions are usually
194	compatible to older versions, so a larger minor version alone is usually	194	compatible to older versions, so a larger minor version alone is usually
195	not a problem.	195	not a problem.
196		196
197	Example: Make sure we haven't accidentally been linked against the wrong	197	Example: Make sure we haven't accidentally been linked against the wrong
198	version (note, however, that this will not detect ABI mismatches :).	198	version (note, however, that this will not detect other ABI mismatches,
		199	such as LFS or reentrancy).
199		200
200	assert (("libev version mismatch",	201	assert (("libev version mismatch",
201	ev_version_major () == EV_VERSION_MAJOR	202	ev_version_major () == EV_VERSION_MAJOR
202	&& ev_version_minor () >= EV_VERSION_MINOR));	203	&& ev_version_minor () >= EV_VERSION_MINOR));
203		204
…		…
225	probe for if you specify no backends explicitly.	226	probe for if you specify no backends explicitly.
226		227
227	=item unsigned int ev_embeddable_backends ()	228	=item unsigned int ev_embeddable_backends ()
228		229
229	Returns the set of backends that are embeddable in other event loops. This	230	Returns the set of backends that are embeddable in other event loops. This
230	is the theoretical, all-platform, value. To find which backends	231	value is platform-specific but can include backends not available on the
231	might be supported on the current system, you would need to look at	232	current system. To find which embeddable backends might be supported on
232	C<ev_embeddable_backends () & ev_supported_backends ()>, likewise for	233	the current system, you would need to look at C<ev_embeddable_backends ()
233	recommended ones.	234	& ev_supported_backends ()>, likewise for recommended ones.
234		235
235	See the description of C<ev_embed> watchers for more info.	236	See the description of C<ev_embed> watchers for more info.
236		237
237	=item ev_set_allocator (void (cb)(void *ptr, long size)) [NOT REENTRANT]	238	=item ev_set_allocator (void (cb)(void *ptr, long size)) [NOT REENTRANT]
238		239
…		…
292	...	293	...
293	ev_set_syserr_cb (fatal_error);	294	ev_set_syserr_cb (fatal_error);
294		295
295	=back	296	=back
296		297
297	=head1 FUNCTIONS CONTROLLING THE EVENT LOOP	298	=head1 FUNCTIONS CONTROLLING EVENT LOOPS
298		299
299	An event loop is described by a C<struct ev_loop *> (the C<struct> is	300	An event loop is described by a C<struct ev_loop *> (the C<struct> is
300	I<not> optional in this case unless libev 3 compatibility is disabled, as	301	I<not> optional in this case unless libev 3 compatibility is disabled, as
301	libev 3 had an C<ev_loop> function colliding with the struct name).	302	libev 3 had an C<ev_loop> function colliding with the struct name).
302		303
…		…
306		307
307	=over 4	308	=over 4
308		309
309	=item struct ev_loop *ev_default_loop (unsigned int flags)	310	=item struct ev_loop *ev_default_loop (unsigned int flags)
310		311
311	This will initialise the default event loop if it hasn't been initialised	312	This returns the "default" event loop object, which is what you should
312	yet and return it. If the default loop could not be initialised, returns	313	normally use when you just need "the event loop". Event loop objects and
313	false. If it already was initialised it simply returns it (and ignores the	314	the C<flags> parameter are described in more detail in the entry for
314	flags. If that is troubling you, check C<ev_backend ()> afterwards).	315	C<ev_loop_new>.
		316
		317	If the default loop is already initialised then this function simply
		318	returns it (and ignores the flags. If that is troubling you, check
		319	C<ev_backend ()> afterwards). Otherwise it will create it with the given
		320	flags, which should almost always be C<0>, unless the caller is also the
		321	one calling C<ev_run> or otherwise qualifies as "the main program".
315		322
316	If you don't know what event loop to use, use the one returned from this	323	If you don't know what event loop to use, use the one returned from this
317	function.	324	function (or via the C<EV_DEFAULT> macro).
318		325
319	Note that this function is I<not> thread-safe, so if you want to use it	326	Note that this function is I<not> thread-safe, so if you want to use it
320	from multiple threads, you have to lock (note also that this is unlikely,	327	from multiple threads, you have to employ some kind of mutex (note also
321	as loops cannot be shared easily between threads anyway).	328	that this case is unlikely, as loops cannot be shared easily between
		329	threads anyway).
322		330
323	The default loop is the only loop that can handle C<ev_signal> and	331	The default loop is the only loop that can handle C<ev_child> watchers,
324	C<ev_child> watchers, and to do this, it always registers a handler	332	and to do this, it always registers a handler for C<SIGCHLD>. If this is
325	for C<SIGCHLD>. If this is a problem for your application you can either	333	a problem for your application you can either create a dynamic loop with
326	create a dynamic loop with C<ev_loop_new> that doesn't do that, or you	334	C<ev_loop_new> which doesn't do that, or you can simply overwrite the
327	can simply overwrite the C<SIGCHLD> signal handler I<after> calling	335	C<SIGCHLD> signal handler I<after> calling C<ev_default_init>.
328	C<ev_default_init>.	336
		337	Example: This is the most typical usage.
		338
		339	if (!ev_default_loop (0))
		340	fatal ("could not initialise libev, bad $LIBEV_FLAGS in environment?");
		341
		342	Example: Restrict libev to the select and poll backends, and do not allow
		343	environment settings to be taken into account:
		344
		345	ev_default_loop (EVBACKEND_POLL \| EVBACKEND_SELECT \| EVFLAG_NOENV);
		346
		347	Example: Use whatever libev has to offer, but make sure that kqueue is
		348	used if available (warning, breaks stuff, best use only with your own
		349	private event loop and only if you know the OS supports your types of
		350	fds):
		351
		352	ev_default_loop (ev_recommended_backends () \| EVBACKEND_KQUEUE);
		353
		354	=item struct ev_loop *ev_loop_new (unsigned int flags)
		355
		356	This will create and initialise a new event loop object. If the loop
		357	could not be initialised, returns false.
		358
		359	Note that this function I<is> thread-safe, and one common way to use
		360	libev with threads is indeed to create one loop per thread, and using the
		361	default loop in the "main" or "initial" thread.
329		362
330	The flags argument can be used to specify special behaviour or specific	363	The flags argument can be used to specify special behaviour or specific
331	backends to use, and is usually specified as C<0> (or C<EVFLAG_AUTO>).	364	backends to use, and is usually specified as C<0> (or C<EVFLAG_AUTO>).
332		365
333	The following flags are supported:	366	The following flags are supported:
…		…
551	If one or more of the backend flags are or'ed into the flags value,	584	If one or more of the backend flags are or'ed into the flags value,
552	then only these backends will be tried (in the reverse order as listed	585	then only these backends will be tried (in the reverse order as listed
553	here). If none are specified, all backends in C<ev_recommended_backends	586	here). If none are specified, all backends in C<ev_recommended_backends
554	()> will be tried.	587	()> will be tried.
555		588
556	Example: This is the most typical usage.
557
558	if (!ev_default_loop (0))
559	fatal ("could not initialise libev, bad $LIBEV_FLAGS in environment?");
560
561	Example: Restrict libev to the select and poll backends, and do not allow
562	environment settings to be taken into account:
563
564	ev_default_loop (EVBACKEND_POLL \| EVBACKEND_SELECT \| EVFLAG_NOENV);
565
566	Example: Use whatever libev has to offer, but make sure that kqueue is
567	used if available (warning, breaks stuff, best use only with your own
568	private event loop and only if you know the OS supports your types of
569	fds):
570
571	ev_default_loop (ev_recommended_backends () \| EVBACKEND_KQUEUE);
572
573	=item struct ev_loop *ev_loop_new (unsigned int flags)
574
575	Similar to C<ev_default_loop>, but always creates a new event loop that is
576	always distinct from the default loop.
577
578	Note that this function I<is> thread-safe, and one common way to use
579	libev with threads is indeed to create one loop per thread, and using the
580	default loop in the "main" or "initial" thread.
581
582	Example: Try to create a event loop that uses epoll and nothing else.	589	Example: Try to create a event loop that uses epoll and nothing else.
583		590
584	struct ev_loop *epoller = ev_loop_new (EVBACKEND_EPOLL \| EVFLAG_NOENV);	591	struct ev_loop *epoller = ev_loop_new (EVBACKEND_EPOLL \| EVFLAG_NOENV);
585	if (!epoller)	592	if (!epoller)
586	fatal ("no epoll found here, maybe it hides under your chair");	593	fatal ("no epoll found here, maybe it hides under your chair");
587		594
588	=item ev_default_destroy ()	595	=item ev_loop_destroy (loop)
589		596
590	Destroys the default loop (frees all memory and kernel state etc.). None	597	Destroys an event loop object (frees all memory and kernel state
591	of the active event watchers will be stopped in the normal sense, so	598	etc.). None of the active event watchers will be stopped in the normal
592	e.g. C<ev_is_active> might still return true. It is your responsibility to	599	sense, so e.g. C<ev_is_active> might still return true. It is your
593	either stop all watchers cleanly yourself I<before> calling this function,	600	responsibility to either stop all watchers cleanly yourself I<before>
594	or cope with the fact afterwards (which is usually the easiest thing, you	601	calling this function, or cope with the fact afterwards (which is usually
595	can just ignore the watchers and/or C<free ()> them for example).	602	the easiest thing, you can just ignore the watchers and/or C<free ()> them
		603	for example).
596		604
597	Note that certain global state, such as signal state (and installed signal	605	Note that certain global state, such as signal state (and installed signal
598	handlers), will not be freed by this function, and related watchers (such	606	handlers), will not be freed by this function, and related watchers (such
599	as signal and child watchers) would need to be stopped manually.	607	as signal and child watchers) would need to be stopped manually.
600		608
601	In general it is not advisable to call this function except in the	609	This function is normally used on loop objects allocated by
602	rare occasion where you really need to free e.g. the signal handling	610	C<ev_loop_new>, but it can also be used on the default loop returned by
		611	C<ev_default_loop>, in which case it is not thread-safe.
		612
		613	Note that it is not advisable to call this function on the default loop
		614	except in the rare occasion where you really need to free it's resources.
603	pipe fds. If you need dynamically allocated loops it is better to use	615	If you need dynamically allocated loops it is better to use C<ev_loop_new>
604	C<ev_loop_new> and C<ev_loop_destroy>.	616	and C<ev_loop_destroy>.
605		617
606	=item ev_loop_destroy (loop)	618	=item ev_loop_fork (loop)
607		619
608	Like C<ev_default_destroy>, but destroys an event loop created by an
609	earlier call to C<ev_loop_new>.
610
611	=item ev_default_fork ()
612
613	This function sets a flag that causes subsequent C<ev_run> iterations	620	This function sets a flag that causes subsequent C<ev_run> iterations to
614	to reinitialise the kernel state for backends that have one. Despite the	621	reinitialise the kernel state for backends that have one. Despite the
615	name, you can call it anytime, but it makes most sense after forking, in	622	name, you can call it anytime, but it makes most sense after forking, in
616	the child process (or both child and parent, but that again makes little	623	the child process. You I<must> call it (or use C<EVFLAG_FORKCHECK>) in the
617	sense). You I<must> call it in the child before using any of the libev	624	child before resuming or calling C<ev_run>.
618	functions, and it will only take effect at the next C<ev_run> iteration.
619		625
620	Again, you I<have> to call it on I<any> loop that you want to re-use after	626	Again, you I<have> to call it on I<any> loop that you want to re-use after
621	a fork, I<even if you do not plan to use the loop in the parent>. This is	627	a fork, I<even if you do not plan to use the loop in the parent>. This is
622	because some kernel interfaces cough I<kqueue> cough do funny things	628	because some kernel interfaces cough I<kqueue> cough do funny things
623	during fork.	629	during fork.
…		…
628	call it at all (in fact, C<epoll> is so badly broken that it makes a	634	call it at all (in fact, C<epoll> is so badly broken that it makes a
629	difference, but libev will usually detect this case on its own and do a	635	difference, but libev will usually detect this case on its own and do a
630	costly reset of the backend).	636	costly reset of the backend).
631		637
632	The function itself is quite fast and it's usually not a problem to call	638	The function itself is quite fast and it's usually not a problem to call
633	it just in case after a fork. To make this easy, the function will fit in	639	it just in case after a fork.
634	quite nicely into a call to C<pthread_atfork>:
635		640
		641	Example: Automate calling C<ev_loop_fork> on the default loop when
		642	using pthreads.
		643
		644	static void
		645	post_fork_child (void)
		646	{
		647	ev_loop_fork (EV_DEFAULT);
		648	}
		649
		650	...
636	pthread_atfork (0, 0, ev_default_fork);	651	pthread_atfork (0, 0, post_fork_child);
637
638	=item ev_loop_fork (loop)
639
640	Like C<ev_default_fork>, but acts on an event loop created by
641	C<ev_loop_new>. Yes, you have to call this on every allocated event loop
642	after fork that you want to re-use in the child, and how you keep track of
643	them is entirely your own problem.
644		652
645	=item int ev_is_default_loop (loop)	653	=item int ev_is_default_loop (loop)
646		654
647	Returns true when the given loop is, in fact, the default loop, and false	655	Returns true when the given loop is, in fact, the default loop, and false
648	otherwise.	656	otherwise.
…		…
3074	disadvantage of having to use multiple event loops (which do not support	3082	disadvantage of having to use multiple event loops (which do not support
3075	signal watchers).	3083	signal watchers).
3076		3084
3077	When this is not possible, or you want to use the default loop for	3085	When this is not possible, or you want to use the default loop for
3078	other reasons, then in the process that wants to start "fresh", call	3086	other reasons, then in the process that wants to start "fresh", call
3079	C<ev_default_destroy ()> followed by C<ev_default_loop (...)>. Destroying	3087	C<ev_loop_destroy (EV_DEFAULT)> followed by C<ev_default_loop (...)>.
3080	the default loop will "orphan" (not stop) all registered watchers, so you	3088	Destroying the default loop will "orphan" (not stop) all registered
3081	have to be careful not to execute code that modifies those watchers. Note	3089	watchers, so you have to be careful not to execute code that modifies
3082	also that in that case, you have to re-register any signal watchers.	3090	those watchers. Note also that in that case, you have to re-register any
		3091	signal watchers.
3083		3092
3084	=head3 Watcher-Specific Functions and Data Members	3093	=head3 Watcher-Specific Functions and Data Members
3085		3094
3086	=over 4	3095	=over 4
3087		3096
…		…
4829	compatibility, so most programs should still compile. Those might be	4838	compatibility, so most programs should still compile. Those might be
4830	removed in later versions of libev, so better update early than late.	4839	removed in later versions of libev, so better update early than late.
4831		4840
4832	=over 4	4841	=over 4
4833		4842
		4843	=item C<ev_default_destroy> and C<ev_default_fork> have been removed
		4844
		4845	These calls can be replaced easily by their C<ev_loop_xxx> counterparts:
		4846
		4847	ev_loop_destroy (EV_DEFAULT);
		4848	ev_loop_fork (EV_DEFAULT);
		4849
4834	=item function/symbol renames	4850	=item function/symbol renames
4835		4851
4836	A number of functions and symbols have been renamed:	4852	A number of functions and symbols have been renamed:
4837		4853
4838	ev_loop => ev_run	4854	ev_loop => ev_run

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Comparing libev/ev.pod (file contents): Revision 1.318 by root, Fri Oct 22 09:40:22 2010 UTC vs. Revision 1.322 by root, Sun Oct 24 17:58:41 2010 UTC

Diff Legend

Comparing libev/ev.pod (file contents):
Revision 1.318 by root, Fri Oct 22 09:40:22 2010 UTC vs.
Revision 1.322 by root, Sun Oct 24 17:58:41 2010 UTC