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

Comparing libev/ev.pod (file contents):
Revision 1.285 by root, Tue Mar 16 00:20:17 2010 UTC vs.
Revision 1.303 by root, Thu Oct 14 04:29:34 2010 UTC

…		…
75	While this document tries to be as complete as possible in documenting	75	While this document tries to be as complete as possible in documenting
76	libev, its usage and the rationale behind its design, it is not a tutorial	76	libev, its usage and the rationale behind its design, it is not a tutorial
77	on event-based programming, nor will it introduce event-based programming	77	on event-based programming, nor will it introduce event-based programming
78	with libev.	78	with libev.
79		79
80	Familarity with event based programming techniques in general is assumed	80	Familiarity with event based programming techniques in general is assumed
81	throughout this document.	81	throughout this document.
82		82
83	=head1 ABOUT LIBEV	83	=head1 ABOUT LIBEV
84		84
85	Libev is an event loop: you register interest in certain events (such as a	85	Libev is an event loop: you register interest in certain events (such as a
…		…
124	this argument.	124	this argument.
125		125
126	=head2 TIME REPRESENTATION	126	=head2 TIME REPRESENTATION
127		127
128	Libev represents time as a single floating point number, representing	128	Libev represents time as a single floating point number, representing
129	the (fractional) number of seconds since the (POSIX) epoch (somewhere	129	the (fractional) number of seconds since the (POSIX) epoch (in practise
130	near the beginning of 1970, details are complicated, don't ask). This	130	somewhere near the beginning of 1970, details are complicated, don't
131	type is called C<ev_tstamp>, which is what you should use too. It usually	131	ask). This type is called C<ev_tstamp>, which is what you should use
132	aliases to the C<double> type in C. When you need to do any calculations	132	too. It usually aliases to the C<double> type in C. When you need to do
133	on it, you should treat it as some floating point value. Unlike the name	133	any calculations on it, you should treat it as some floating point value.
		134
134	component C<stamp> might indicate, it is also used for time differences	135	Unlike the name component C<stamp> might indicate, it is also used for
135	throughout libev.	136	time differences (e.g. delays) throughout libev.
136		137
137	=head1 ERROR HANDLING	138	=head1 ERROR HANDLING
138		139
139	Libev knows three classes of errors: operating system errors, usage errors	140	Libev knows three classes of errors: operating system errors, usage errors
140	and internal errors (bugs).	141	and internal errors (bugs).
…		…
191	as this indicates an incompatible change. Minor versions are usually	192	as this indicates an incompatible change. Minor versions are usually
192	compatible to older versions, so a larger minor version alone is usually	193	compatible to older versions, so a larger minor version alone is usually
193	not a problem.	194	not a problem.
194		195
195	Example: Make sure we haven't accidentally been linked against the wrong	196	Example: Make sure we haven't accidentally been linked against the wrong
196	version.	197	version (note, however, that this will not detect ABI mismatches :).
197		198
198	assert (("libev version mismatch",	199	assert (("libev version mismatch",
199	ev_version_major () == EV_VERSION_MAJOR	200	ev_version_major () == EV_VERSION_MAJOR
200	&& ev_version_minor () >= EV_VERSION_MINOR));	201	&& ev_version_minor () >= EV_VERSION_MINOR));
201		202
…		…
345	useful to try out specific backends to test their performance, or to work	346	useful to try out specific backends to test their performance, or to work
346	around bugs.	347	around bugs.
347		348
348	=item C<EVFLAG_FORKCHECK>	349	=item C<EVFLAG_FORKCHECK>
349		350
350	Instead of calling C<ev_default_fork> or C<ev_loop_fork> manually after	351	Instead of calling C<ev_loop_fork> manually after a fork, you can also
351	a fork, you can also make libev check for a fork in each iteration by	352	make libev check for a fork in each iteration by enabling this flag.
352	enabling this flag.
353		353
354	This works by calling C<getpid ()> on every iteration of the loop,	354	This works by calling C<getpid ()> on every iteration of the loop,
355	and thus this might slow down your event loop if you do a lot of loop	355	and thus this might slow down your event loop if you do a lot of loop
356	iterations and little real work, but is usually not noticeable (on my	356	iterations and little real work, but is usually not noticeable (on my
357	GNU/Linux system for example, C<getpid> is actually a simple 5-insn sequence	357	GNU/Linux system for example, C<getpid> is actually a simple 5-insn sequence
…		…
567	ev_default_loop (ev_recommended_backends () \| EVBACKEND_KQUEUE);	567	ev_default_loop (ev_recommended_backends () \| EVBACKEND_KQUEUE);
568		568
569	=item struct ev_loop *ev_loop_new (unsigned int flags)	569	=item struct ev_loop *ev_loop_new (unsigned int flags)
570		570
571	Similar to C<ev_default_loop>, but always creates a new event loop that is	571	Similar to C<ev_default_loop>, but always creates a new event loop that is
572	always distinct from the default loop. Unlike the default loop, it cannot	572	always distinct from the default loop.
573	handle signal and child watchers, and attempts to do so will be greeted by
574	undefined behaviour (or a failed assertion if assertions are enabled).
575		573
576	Note that this function I<is> thread-safe, and the recommended way to use	574	Note that this function I<is> thread-safe, and one common way to use
577	libev with threads is indeed to create one loop per thread, and using the	575	libev with threads is indeed to create one loop per thread, and using the
578	default loop in the "main" or "initial" thread.	576	default loop in the "main" or "initial" thread.
579		577
580	Example: Try to create a event loop that uses epoll and nothing else.	578	Example: Try to create a event loop that uses epoll and nothing else.
581		579
…		…
583	if (!epoller)	581	if (!epoller)
584	fatal ("no epoll found here, maybe it hides under your chair");	582	fatal ("no epoll found here, maybe it hides under your chair");
585		583
586	=item ev_default_destroy ()	584	=item ev_default_destroy ()
587		585
588	Destroys the default loop again (frees all memory and kernel state	586	Destroys the default loop (frees all memory and kernel state etc.). None
589	etc.). None of the active event watchers will be stopped in the normal	587	of the active event watchers will be stopped in the normal sense, so
590	sense, so e.g. C<ev_is_active> might still return true. It is your	588	e.g. C<ev_is_active> might still return true. It is your responsibility to
591	responsibility to either stop all watchers cleanly yourself I<before>	589	either stop all watchers cleanly yourself I<before> calling this function,
592	calling this function, or cope with the fact afterwards (which is usually	590	or cope with the fact afterwards (which is usually the easiest thing, you
593	the easiest thing, you can just ignore the watchers and/or C<free ()> them	591	can just ignore the watchers and/or C<free ()> them for example).
594	for example).
595		592
596	Note that certain global state, such as signal state (and installed signal	593	Note that certain global state, such as signal state (and installed signal
597	handlers), will not be freed by this function, and related watchers (such	594	handlers), will not be freed by this function, and related watchers (such
598	as signal and child watchers) would need to be stopped manually.	595	as signal and child watchers) would need to be stopped manually.
599		596
…		…
614	name, you can call it anytime, but it makes most sense after forking, in	611	name, you can call it anytime, but it makes most sense after forking, in
615	the child process (or both child and parent, but that again makes little	612	the child process (or both child and parent, but that again makes little
616	sense). You I<must> call it in the child before using any of the libev	613	sense). You I<must> call it in the child before using any of the libev
617	functions, and it will only take effect at the next C<ev_loop> iteration.	614	functions, and it will only take effect at the next C<ev_loop> iteration.
618		615
		616	Again, you I<have> to call it on I<any> loop that you want to re-use after
		617	a fork, I<even if you do not plan to use the loop in the parent>. This is
		618	because some kernel interfaces cough I<kqueue> cough do funny things
		619	during fork.
		620
619	On the other hand, you only need to call this function in the child	621	On the other hand, you only need to call this function in the child
620	process if and only if you want to use the event library in the child. If	622	process if and only if you want to use the event loop in the child. If you
621	you just fork+exec, you don't have to call it at all.	623	just fork+exec or create a new loop in the child, you don't have to call
		624	it at all.
622		625
623	The function itself is quite fast and it's usually not a problem to call	626	The function itself is quite fast and it's usually not a problem to call
624	it just in case after a fork. To make this easy, the function will fit in	627	it just in case after a fork. To make this easy, the function will fit in
625	quite nicely into a call to C<pthread_atfork>:	628	quite nicely into a call to C<pthread_atfork>:
626		629
…		…
628		631
629	=item ev_loop_fork (loop)	632	=item ev_loop_fork (loop)
630		633
631	Like C<ev_default_fork>, but acts on an event loop created by	634	Like C<ev_default_fork>, but acts on an event loop created by
632	C<ev_loop_new>. Yes, you have to call this on every allocated event loop	635	C<ev_loop_new>. Yes, you have to call this on every allocated event loop
633	after fork that you want to re-use in the child, and how you do this is	636	after fork that you want to re-use in the child, and how you keep track of
634	entirely your own problem.	637	them is entirely your own problem.
635		638
636	=item int ev_is_default_loop (loop)	639	=item int ev_is_default_loop (loop)
637		640
638	Returns true when the given loop is, in fact, the default loop, and false	641	Returns true when the given loop is, in fact, the default loop, and false
639	otherwise.	642	otherwise.
640		643
641	=item unsigned int ev_loop_count (loop)	644	=item unsigned int ev_iteration (loop)
642		645
643	Returns the count of loop iterations for the loop, which is identical to	646	Returns the current iteration count for the loop, which is identical to
644	the number of times libev did poll for new events. It starts at C<0> and	647	the number of times libev did poll for new events. It starts at C<0> and
645	happily wraps around with enough iterations.	648	happily wraps around with enough iterations.
646		649
647	This value can sometimes be useful as a generation counter of sorts (it	650	This value can sometimes be useful as a generation counter of sorts (it
648	"ticks" the number of loop iterations), as it roughly corresponds with	651	"ticks" the number of loop iterations), as it roughly corresponds with
649	C<ev_prepare> and C<ev_check> calls.	652	C<ev_prepare> and C<ev_check> calls - and is incremented between the
		653	prepare and check phases.
650		654
651	=item unsigned int ev_loop_depth (loop)	655	=item unsigned int ev_depth (loop)
652		656
653	Returns the number of times C<ev_loop> was entered minus the number of	657	Returns the number of times C<ev_loop> was entered minus the number of
654	times C<ev_loop> was exited, in other words, the recursion depth.	658	times C<ev_loop> was exited, in other words, the recursion depth.
655		659
656	Outside C<ev_loop>, this number is zero. In a callback, this number is	660	Outside C<ev_loop>, this number is zero. In a callback, this number is
657	C<1>, unless C<ev_loop> was invoked recursively (or from another thread),	661	C<1>, unless C<ev_loop> was invoked recursively (or from another thread),
658	in which case it is higher.	662	in which case it is higher.
659		663
660	Leaving C<ev_loop> abnormally (setjmp/longjmp, cancelling the thread	664	Leaving C<ev_loop> abnormally (setjmp/longjmp, cancelling the thread
661	etc.), doesn't count as exit.	665	etc.), doesn't count as "exit" - consider this as a hint to avoid such
		666	ungentleman behaviour unless it's really convenient.
662		667
663	=item unsigned int ev_backend (loop)	668	=item unsigned int ev_backend (loop)
664		669
665	Returns one of the C<EVBACKEND_*> flags indicating the event backend in	670	Returns one of the C<EVBACKEND_*> flags indicating the event backend in
666	use.	671	use.
…		…
700	C<ev_resume> directly afterwards to resume timer processing.	705	C<ev_resume> directly afterwards to resume timer processing.
701		706
702	Effectively, all C<ev_timer> watchers will be delayed by the time spend	707	Effectively, all C<ev_timer> watchers will be delayed by the time spend
703	between C<ev_suspend> and C<ev_resume>, and all C<ev_periodic> watchers	708	between C<ev_suspend> and C<ev_resume>, and all C<ev_periodic> watchers
704	will be rescheduled (that is, they will lose any events that would have	709	will be rescheduled (that is, they will lose any events that would have
705	occured while suspended).	710	occurred while suspended).
706		711
707	After calling C<ev_suspend> you B<must not> call I<any> function on the	712	After calling C<ev_suspend> you B<must not> call I<any> function on the
708	given loop other than C<ev_resume>, and you B<must not> call C<ev_resume>	713	given loop other than C<ev_resume>, and you B<must not> call C<ev_resume>
709	without a previous call to C<ev_suspend>.	714	without a previous call to C<ev_suspend>.
710		715
…		…
787	C<EVUNLOOP_ONE>, which will make the innermost C<ev_loop> call return, or	792	C<EVUNLOOP_ONE>, which will make the innermost C<ev_loop> call return, or
788	C<EVUNLOOP_ALL>, which will make all nested C<ev_loop> calls return.	793	C<EVUNLOOP_ALL>, which will make all nested C<ev_loop> calls return.
789		794
790	This "unloop state" will be cleared when entering C<ev_loop> again.	795	This "unloop state" will be cleared when entering C<ev_loop> again.
791		796
792	It is safe to call C<ev_unloop> from otuside any C<ev_loop> calls.	797	It is safe to call C<ev_unloop> from outside any C<ev_loop> calls.
793		798
794	=item ev_ref (loop)	799	=item ev_ref (loop)
795		800
796	=item ev_unref (loop)	801	=item ev_unref (loop)
797		802
…		…
867	usually doesn't make much sense to set it to a lower value than C<0.01>,	872	usually doesn't make much sense to set it to a lower value than C<0.01>,
868	as this approaches the timing granularity of most systems. Note that if	873	as this approaches the timing granularity of most systems. Note that if
869	you do transactions with the outside world and you can't increase the	874	you do transactions with the outside world and you can't increase the
870	parallelity, then this setting will limit your transaction rate (if you	875	parallelity, then this setting will limit your transaction rate (if you
871	need to poll once per transaction and the I/O collect interval is 0.01,	876	need to poll once per transaction and the I/O collect interval is 0.01,
872	then you can't do more than 100 transations per second).	877	then you can't do more than 100 transactions per second).
873		878
874	Setting the I<timeout collect interval> can improve the opportunity for	879	Setting the I<timeout collect interval> can improve the opportunity for
875	saving power, as the program will "bundle" timer callback invocations that	880	saving power, as the program will "bundle" timer callback invocations that
876	are "near" in time together, by delaying some, thus reducing the number of	881	are "near" in time together, by delaying some, thus reducing the number of
877	times the process sleeps and wakes up again. Another useful technique to	882	times the process sleeps and wakes up again. Another useful technique to
…		…
1032	=item C<EV_WRITE>	1037	=item C<EV_WRITE>
1033		1038
1034	The file descriptor in the C<ev_io> watcher has become readable and/or	1039	The file descriptor in the C<ev_io> watcher has become readable and/or
1035	writable.	1040	writable.
1036		1041
1037	=item C<EV_TIMEOUT>	1042	=item C<EV_TIMER>
1038		1043
1039	The C<ev_timer> watcher has timed out.	1044	The C<ev_timer> watcher has timed out.
1040		1045
1041	=item C<EV_PERIODIC>	1046	=item C<EV_PERIODIC>
1042		1047
…		…
1375		1380
1376	For example, to emulate how many other event libraries handle priorities,	1381	For example, to emulate how many other event libraries handle priorities,
1377	you can associate an C<ev_idle> watcher to each such watcher, and in	1382	you can associate an C<ev_idle> watcher to each such watcher, and in
1378	the normal watcher callback, you just start the idle watcher. The real	1383	the normal watcher callback, you just start the idle watcher. The real
1379	processing is done in the idle watcher callback. This causes libev to	1384	processing is done in the idle watcher callback. This causes libev to
1380	continously poll and process kernel event data for the watcher, but when	1385	continuously poll and process kernel event data for the watcher, but when
1381	the lock-out case is known to be rare (which in turn is rare :), this is	1386	the lock-out case is known to be rare (which in turn is rare :), this is
1382	workable.	1387	workable.
1383		1388
1384	Usually, however, the lock-out model implemented that way will perform	1389	Usually, however, the lock-out model implemented that way will perform
1385	miserably under the type of load it was designed to handle. In that case,	1390	miserably under the type of load it was designed to handle. In that case,
…		…
1399	{	1404	{
1400	// stop the I/O watcher, we received the event, but	1405	// stop the I/O watcher, we received the event, but
1401	// are not yet ready to handle it.	1406	// are not yet ready to handle it.
1402	ev_io_stop (EV_A_ w);	1407	ev_io_stop (EV_A_ w);
1403		1408
1404	// start the idle watcher to ahndle the actual event.	1409	// start the idle watcher to handle the actual event.
1405	// it will not be executed as long as other watchers	1410	// it will not be executed as long as other watchers
1406	// with the default priority are receiving events.	1411	// with the default priority are receiving events.
1407	ev_idle_start (EV_A_ &idle);	1412	ev_idle_start (EV_A_ &idle);
1408	}	1413	}
1409		1414
…		…
1463		1468
1464	If you cannot use non-blocking mode, then force the use of a	1469	If you cannot use non-blocking mode, then force the use of a
1465	known-to-be-good backend (at the time of this writing, this includes only	1470	known-to-be-good backend (at the time of this writing, this includes only
1466	C<EVBACKEND_SELECT> and C<EVBACKEND_POLL>). The same applies to file	1471	C<EVBACKEND_SELECT> and C<EVBACKEND_POLL>). The same applies to file
1467	descriptors for which non-blocking operation makes no sense (such as	1472	descriptors for which non-blocking operation makes no sense (such as
1468	files) - libev doesn't guarentee any specific behaviour in that case.	1473	files) - libev doesn't guarantee any specific behaviour in that case.
1469		1474
1470	Another thing you have to watch out for is that it is quite easy to	1475	Another thing you have to watch out for is that it is quite easy to
1471	receive "spurious" readiness notifications, that is your callback might	1476	receive "spurious" readiness notifications, that is your callback might
1472	be called with C<EV_READ> but a subsequent C<read>(2) will actually block	1477	be called with C<EV_READ> but a subsequent C<read>(2) will actually block
1473	because there is no data. Not only are some backends known to create a	1478	because there is no data. Not only are some backends known to create a
…		…
1541	somewhere, as that would have given you a big clue).	1546	somewhere, as that would have given you a big clue).
1542		1547
1543	=head3 The special problem of accept()ing when you can't	1548	=head3 The special problem of accept()ing when you can't
1544		1549
1545	Many implementations of the POSIX C<accept> function (for example,	1550	Many implementations of the POSIX C<accept> function (for example,
1546	found in port-2004 Linux) have the peculiar behaviour of not removing a	1551	found in post-2004 Linux) have the peculiar behaviour of not removing a
1547	connection from the pending queue in all error cases.	1552	connection from the pending queue in all error cases.
1548		1553
1549	For example, larger servers often run out of file descriptors (because	1554	For example, larger servers often run out of file descriptors (because
1550	of resource limits), causing C<accept> to fail with C<ENFILE> but not	1555	of resource limits), causing C<accept> to fail with C<ENFILE> but not
1551	rejecting the connection, leading to libev signalling readiness on	1556	rejecting the connection, leading to libev signalling readiness on
…		…
1732	ev_tstamp timeout = last_activity + 60.;	1737	ev_tstamp timeout = last_activity + 60.;
1733		1738
1734	// if last_activity + 60. is older than now, we did time out	1739	// if last_activity + 60. is older than now, we did time out
1735	if (timeout < now)	1740	if (timeout < now)
1736	{	1741	{
1737	// timeout occured, take action	1742	// timeout occurred, take action
1738	}	1743	}
1739	else	1744	else
1740	{	1745	{
1741	// callback was invoked, but there was some activity, re-arm	1746	// callback was invoked, but there was some activity, re-arm
1742	// the watcher to fire in last_activity + 60, which is	1747	// the watcher to fire in last_activity + 60, which is
…		…
1764	to the current time (meaning we just have some activity :), then call the	1769	to the current time (meaning we just have some activity :), then call the
1765	callback, which will "do the right thing" and start the timer:	1770	callback, which will "do the right thing" and start the timer:
1766		1771
1767	ev_init (timer, callback);	1772	ev_init (timer, callback);
1768	last_activity = ev_now (loop);	1773	last_activity = ev_now (loop);
1769	callback (loop, timer, EV_TIMEOUT);	1774	callback (loop, timer, EV_TIMER);
1770		1775
1771	And when there is some activity, simply store the current time in	1776	And when there is some activity, simply store the current time in
1772	C<last_activity>, no libev calls at all:	1777	C<last_activity>, no libev calls at all:
1773		1778
1774	last_actiivty = ev_now (loop);	1779	last_activity = ev_now (loop);
1775		1780
1776	This technique is slightly more complex, but in most cases where the	1781	This technique is slightly more complex, but in most cases where the
1777	time-out is unlikely to be triggered, much more efficient.	1782	time-out is unlikely to be triggered, much more efficient.
1778		1783
1779	Changing the timeout is trivial as well (if it isn't hard-coded in the	1784	Changing the timeout is trivial as well (if it isn't hard-coded in the
…		…
2118	Example: Call a callback every hour, or, more precisely, whenever the	2123	Example: Call a callback every hour, or, more precisely, whenever the
2119	system time is divisible by 3600. The callback invocation times have	2124	system time is divisible by 3600. The callback invocation times have
2120	potentially a lot of jitter, but good long-term stability.	2125	potentially a lot of jitter, but good long-term stability.
2121		2126
2122	static void	2127	static void
2123	clock_cb (struct ev_loop loop, ev_io w, int revents)	2128	clock_cb (struct ev_loop loop, ev_periodic w, int revents)
2124	{	2129	{
2125	... its now a full hour (UTC, or TAI or whatever your clock follows)	2130	... its now a full hour (UTC, or TAI or whatever your clock follows)
2126	}	2131	}
2127		2132
2128	ev_periodic hourly_tick;	2133	ev_periodic hourly_tick;
…		…
2960	C<ev_default_fork> cheats and calls it in the wrong process, the fork	2965	C<ev_default_fork> cheats and calls it in the wrong process, the fork
2961	handlers will be invoked, too, of course.	2966	handlers will be invoked, too, of course.
2962		2967
2963	=head3 The special problem of life after fork - how is it possible?	2968	=head3 The special problem of life after fork - how is it possible?
2964		2969
2965	Most uses of C<fork()> consist of forking, then some simple calls to ste	2970	Most uses of C<fork()> consist of forking, then some simple calls to set
2966	up/change the process environment, followed by a call to C<exec()>. This	2971	up/change the process environment, followed by a call to C<exec()>. This
2967	sequence should be handled by libev without any problems.	2972	sequence should be handled by libev without any problems.
2968		2973
2969	This changes when the application actually wants to do event handling	2974	This changes when the application actually wants to do event handling
2970	in the child, or both parent in child, in effect "continuing" after the	2975	in the child, or both parent in child, in effect "continuing" after the
…		…
3004	believe me.	3009	believe me.
3005		3010
3006	=back	3011	=back
3007		3012
3008		3013
3009	=head2 C<ev_async> - how to wake up another event loop	3014	=head2 C<ev_async> - how to wake up an event loop
3010		3015
3011	In general, you cannot use an C<ev_loop> from multiple threads or other	3016	In general, you cannot use an C<ev_loop> from multiple threads or other
3012	asynchronous sources such as signal handlers (as opposed to multiple event	3017	asynchronous sources such as signal handlers (as opposed to multiple event
3013	loops - those are of course safe to use in different threads).	3018	loops - those are of course safe to use in different threads).
3014		3019
3015	Sometimes, however, you need to wake up another event loop you do not	3020	Sometimes, however, you need to wake up an event loop you do not control,
3016	control, for example because it belongs to another thread. This is what	3021	for example because it belongs to another thread. This is what C<ev_async>
3017	C<ev_async> watchers do: as long as the C<ev_async> watcher is active, you	3022	watchers do: as long as the C<ev_async> watcher is active, you can signal
3018	can signal it by calling C<ev_async_send>, which is thread- and signal	3023	it by calling C<ev_async_send>, which is thread- and signal safe.
3019	safe.
3020		3024
3021	This functionality is very similar to C<ev_signal> watchers, as signals,	3025	This functionality is very similar to C<ev_signal> watchers, as signals,
3022	too, are asynchronous in nature, and signals, too, will be compressed	3026	too, are asynchronous in nature, and signals, too, will be compressed
3023	(i.e. the number of callback invocations may be less than the number of	3027	(i.e. the number of callback invocations may be less than the number of
3024	C<ev_async_sent> calls).	3028	C<ev_async_sent> calls).
…		…
3179		3183
3180	If C<timeout> is less than 0, then no timeout watcher will be	3184	If C<timeout> is less than 0, then no timeout watcher will be
3181	started. Otherwise an C<ev_timer> watcher with after = C<timeout> (and	3185	started. Otherwise an C<ev_timer> watcher with after = C<timeout> (and
3182	repeat = 0) will be started. C<0> is a valid timeout.	3186	repeat = 0) will be started. C<0> is a valid timeout.
3183		3187
3184	The callback has the type C<void (cb)(int revents, void arg)> and gets	3188	The callback has the type C<void (cb)(int revents, void arg)> and is
3185	passed an C<revents> set like normal event callbacks (a combination of	3189	passed an C<revents> set like normal event callbacks (a combination of
3186	C<EV_ERROR>, C<EV_READ>, C<EV_WRITE> or C<EV_TIMEOUT>) and the C<arg>	3190	C<EV_ERROR>, C<EV_READ>, C<EV_WRITE> or C<EV_TIMER>) and the C<arg>
3187	value passed to C<ev_once>. Note that it is possible to receive I<both>	3191	value passed to C<ev_once>. Note that it is possible to receive I<both>
3188	a timeout and an io event at the same time - you probably should give io	3192	a timeout and an io event at the same time - you probably should give io
3189	events precedence.	3193	events precedence.
3190		3194
3191	Example: wait up to ten seconds for data to appear on STDIN_FILENO.	3195	Example: wait up to ten seconds for data to appear on STDIN_FILENO.
3192		3196
3193	static void stdin_ready (int revents, void *arg)	3197	static void stdin_ready (int revents, void *arg)
3194	{	3198	{
3195	if (revents & EV_READ)	3199	if (revents & EV_READ)
3196	/* stdin might have data for us, joy! */;	3200	/* stdin might have data for us, joy! */;
3197	else if (revents & EV_TIMEOUT)	3201	else if (revents & EV_TIMER)
3198	/* doh, nothing entered */;	3202	/* doh, nothing entered */;
3199	}	3203	}
3200		3204
3201	ev_once (STDIN_FILENO, EV_READ, 10., stdin_ready, 0);	3205	ev_once (STDIN_FILENO, EV_READ, 10., stdin_ready, 0);
3202		3206
…		…
3336	myclass obj;	3340	myclass obj;
3337	ev::io iow;	3341	ev::io iow;
3338	iow.set <myclass, &myclass::io_cb> (&obj);	3342	iow.set <myclass, &myclass::io_cb> (&obj);
3339		3343
3340	=item w->set (object *)	3344	=item w->set (object *)
3341
3342	This is an B<experimental> feature that might go away in a future version.
3343		3345
3344	This is a variation of a method callback - leaving out the method to call	3346	This is a variation of a method callback - leaving out the method to call
3345	will default the method to C<operator ()>, which makes it possible to use	3347	will default the method to C<operator ()>, which makes it possible to use
3346	functor objects without having to manually specify the C<operator ()> all	3348	functor objects without having to manually specify the C<operator ()> all
3347	the time. Incidentally, you can then also leave out the template argument	3349	the time. Incidentally, you can then also leave out the template argument
…		…
3660	define before including (or compiling) any of its files. The default in	3662	define before including (or compiling) any of its files. The default in
3661	the absence of autoconf is documented for every option.	3663	the absence of autoconf is documented for every option.
3662		3664
3663	Symbols marked with "(h)" do not change the ABI, and can have different	3665	Symbols marked with "(h)" do not change the ABI, and can have different
3664	values when compiling libev vs. including F<ev.h>, so it is permissible	3666	values when compiling libev vs. including F<ev.h>, so it is permissible
3665	to redefine them before including F<ev.h> without breakign compatibility	3667	to redefine them before including F<ev.h> without breaking compatibility
3666	to a compiled library. All other symbols change the ABI, which means all	3668	to a compiled library. All other symbols change the ABI, which means all
3667	users of libev and the libev code itself must be compiled with compatible	3669	users of libev and the libev code itself must be compiled with compatible
3668	settings.	3670	settings.
3669		3671
3670	=over 4	3672	=over 4
…		…
3882	EV_PREPARE_ENABLE, EV_CHECK_ENABLE, EV_FORK_ENABLE, EV_SIGNAL_ENABLE,	3884	EV_PREPARE_ENABLE, EV_CHECK_ENABLE, EV_FORK_ENABLE, EV_SIGNAL_ENABLE,
3883	EV_ASYNC_ENABLE, EV_CHILD_ENABLE.	3885	EV_ASYNC_ENABLE, EV_CHILD_ENABLE.
3884		3886
3885	If undefined or defined to be C<1> (and the platform supports it), then	3887	If undefined or defined to be C<1> (and the platform supports it), then
3886	the respective watcher type is supported. If defined to be C<0>, then it	3888	the respective watcher type is supported. If defined to be C<0>, then it
3887	is not. Disabling watcher types mainly saves codesize.	3889	is not. Disabling watcher types mainly saves code size.
3888		3890
3889	=item EV_FEATURES	3891	=item EV_FEATURES
3890		3892
3891	If you need to shave off some kilobytes of code at the expense of some	3893	If you need to shave off some kilobytes of code at the expense of some
3892	speed (but with the full API), you can define this symbol to request	3894	speed (but with the full API), you can define this symbol to request
3893	certain subsets of functionality. The default is to enable all features	3895	certain subsets of functionality. The default is to enable all features
3894	that can be enabled on the platform.	3896	that can be enabled on the platform.
3895
3896	Note that using autoconf will usually override most of the features, so
3897	using this symbol makes sense mostly when embedding libev.
3898		3897
3899	A typical way to use this symbol is to define it to C<0> (or to a bitset	3898	A typical way to use this symbol is to define it to C<0> (or to a bitset
3900	with some broad features you want) and then selectively re-enable	3899	with some broad features you want) and then selectively re-enable
3901	additional parts you want, for example if you want everything minimal,	3900	additional parts you want, for example if you want everything minimal,
3902	but multiple event loop support, async and child watchers and the poll	3901	but multiple event loop support, async and child watchers and the poll
…		…
3915		3914
3916	=item C<1> - faster/larger code	3915	=item C<1> - faster/larger code
3917		3916
3918	Use larger code to speed up some operations.	3917	Use larger code to speed up some operations.
3919		3918
3920	Currently this is used to override some inlining decisions (enlarging the roughly	3919	Currently this is used to override some inlining decisions (enlarging the
3921	30% code size on amd64.	3920	code size by roughly 30% on amd64).
3922		3921
3923	Also disables C<assert>'s in the code, unless you define C<NDEBUG>	3922	When optimising for size, use of compiler flags such as C<-Os> with
3924	explicitly to C<0>.	3923	gcc is recommended, as well as C<-DNDEBUG>, as libev contains a number of
3925		3924	assertions.
3926	Use of compiler flags such as C<-Os> with gcc that optimise for size are
3927	recommended when disabling this feature.
3928		3925
3929	=item C<2> - faster/larger data structures	3926	=item C<2> - faster/larger data structures
3930		3927
3931	Replaces the small 2-heap for timer management by a faster 4-heap, larger	3928	Replaces the small 2-heap for timer management by a faster 4-heap, larger
3932	hash table sizes and so on. This will usually further increase codesize	3929	hash table sizes and so on. This will usually further increase code size
3933	and can additionally have an effect on the size of data structures at	3930	and can additionally have an effect on the size of data structures at
3934	runtime.	3931	runtime.
3935		3932
3936	=item C<4> - full API configuration	3933	=item C<4> - full API configuration
3937		3934
3938	This enables priorities (sets C<EV_MAXPRI>=2 and C<EV_MINPRI>=-2), and	3935	This enables priorities (sets C<EV_MAXPRI>=2 and C<EV_MINPRI>=-2), and
3939	enables multiplicity (C<EV_MULTIPLICITY>=1).	3936	enables multiplicity (C<EV_MULTIPLICITY>=1).
3940		3937
		3938	=item C<8> - full API
		3939
3941	It also enables a lot of the "lesser used" core API functions. See C<ev.h>	3940	This enables a lot of the "lesser used" API functions. See C<ev.h> for
3942	for details on which parts of the API are still available without this	3941	details on which parts of the API are still available without this
3943	feature, and do not complain if this subset changes over time.	3942	feature, and do not complain if this subset changes over time.
3944		3943
3945	=item C<8> - enable all optional watcher types	3944	=item C<16> - enable all optional watcher types
3946		3945
3947	Enables all optional watcher types. If you want to selectively enable	3946	Enables all optional watcher types. If you want to selectively enable
3948	only some watcher types other than I/O and timers (e.g. prepare,	3947	only some watcher types other than I/O and timers (e.g. prepare,
3949	embed, async, child...) you can enable them manually by defining	3948	embed, async, child...) you can enable them manually by defining
3950	C<EV_watchertype_ENABLE> to C<1> instead.	3949	C<EV_watchertype_ENABLE> to C<1> instead.
3951		3950
3952	=item C<16> - enable all backends	3951	=item C<32> - enable all backends
3953		3952
3954	This enables all backends - without this feature, you need to enable at	3953	This enables all backends - without this feature, you need to enable at
3955	least one backend manually (C<EV_USE_SELECT> is a good choice).	3954	least one backend manually (C<EV_USE_SELECT> is a good choice).
3956		3955
3957	=item C<32> - enable OS-specific "helper" APIs	3956	=item C<64> - enable OS-specific "helper" APIs
3958		3957
3959	Enable inotify, eventfd, signalfd and similar OS-specific helper APIs by	3958	Enable inotify, eventfd, signalfd and similar OS-specific helper APIs by
3960	default.	3959	default.
3961		3960
3962	=back	3961	=back
3963		3962
3964	Compiling with C<gcc -Os -DEV_STANDALONE -DEV_USE_EPOLL=1 -DEV_FEATURES=0>	3963	Compiling with C<gcc -Os -DEV_STANDALONE -DEV_USE_EPOLL=1 -DEV_FEATURES=0>
3965	reduces the compiled size of libev from 24.7Kb to 6.5Kb on my GNU/Linux	3964	reduces the compiled size of libev from 24.7Kb code/2.8Kb data to 6.5Kb
3966	amd64 system, while still giving you I/O watchers, timers and monotonic	3965	code/0.3Kb data on my GNU/Linux amd64 system, while still giving you I/O
3967	clock support.	3966	watchers, timers and monotonic clock support.
3968		3967
3969	With an intelligent-enough linker (gcc+binutils are intelligent enough	3968	With an intelligent-enough linker (gcc+binutils are intelligent enough
3970	when you use C<-Wl,--gc-sections -ffunction-sections>) functions unused by	3969	when you use C<-Wl,--gc-sections -ffunction-sections>) functions unused by
3971	your program might be left out as well - a binary starting a timer and an	3970	your program might be left out as well - a binary starting a timer and an
3972	I/O watcher then might come out at only 5Kb.	3971	I/O watcher then might come out at only 5Kb.
3973		3972
3974	=item EV_AVOID_STDIO	3973	=item EV_AVOID_STDIO
3975		3974
3976	If this is set to C<1> at compiletime, then libev will avoid using stdio	3975	If this is set to C<1> at compiletime, then libev will avoid using stdio
3977	functions (printf, scanf, perror etc.). This will increase the codesize	3976	functions (printf, scanf, perror etc.). This will increase the code size
3978	somewhat, but if your program doesn't otherwise depend on stdio and your	3977	somewhat, but if your program doesn't otherwise depend on stdio and your
3979	libc allows it, this avoids linking in the stdio library which is quite	3978	libc allows it, this avoids linking in the stdio library which is quite
3980	big.	3979	big.
3981		3980
3982	Note that error messages might become less precise when this option is	3981	Note that error messages might become less precise when this option is
…		…
3986		3985
3987	The highest supported signal number, +1 (or, the number of	3986	The highest supported signal number, +1 (or, the number of
3988	signals): Normally, libev tries to deduce the maximum number of signals	3987	signals): Normally, libev tries to deduce the maximum number of signals
3989	automatically, but sometimes this fails, in which case it can be	3988	automatically, but sometimes this fails, in which case it can be
3990	specified. Also, using a lower number than detected (C<32> should be	3989	specified. Also, using a lower number than detected (C<32> should be
3991	good for about any system in existance) can save some memory, as libev	3990	good for about any system in existence) can save some memory, as libev
3992	statically allocates some 12-24 bytes per signal number.	3991	statically allocates some 12-24 bytes per signal number.
3993		3992
3994	=item EV_PID_HASHSIZE	3993	=item EV_PID_HASHSIZE
3995		3994
3996	C<ev_child> watchers use a small hash table to distribute workload by	3995	C<ev_child> watchers use a small hash table to distribute workload by
…		…
4042	will be C<0>.	4041	will be C<0>.
4043		4042
4044	=item EV_COMMON	4043	=item EV_COMMON
4045		4044
4046	By default, all watchers have a C<void *data> member. By redefining	4045	By default, all watchers have a C<void *data> member. By redefining
4047	this macro to a something else you can include more and other types of	4046	this macro to something else you can include more and other types of
4048	members. You have to define it each time you include one of the files,	4047	members. You have to define it each time you include one of the files,
4049	though, and it must be identical each time.	4048	though, and it must be identical each time.
4050		4049
4051	For example, the perl EV module uses something like this:	4050	For example, the perl EV module uses something like this:
4052		4051
…		…
4105	file.	4104	file.
4106		4105
4107	The usage in rxvt-unicode is simpler. It has a F<ev_cpp.h> header file	4106	The usage in rxvt-unicode is simpler. It has a F<ev_cpp.h> header file
4108	that everybody includes and which overrides some configure choices:	4107	that everybody includes and which overrides some configure choices:
4109		4108
4110	#define EV_FEATURES 0	4109	#define EV_FEATURES 8
4111	#define EV_USE_SELECT 1	4110	#define EV_USE_SELECT 1
		4111	#define EV_PREPARE_ENABLE 1
		4112	#define EV_IDLE_ENABLE 1
		4113	#define EV_SIGNAL_ENABLE 1
		4114	#define EV_CHILD_ENABLE 1
		4115	#define EV_USE_STDEXCEPT 0
4112	#define EV_CONFIG_H <config.h>	4116	#define EV_CONFIG_H <config.h>
4113		4117
4114	#include "ev++.h"	4118	#include "ev++.h"
4115		4119
4116	And a F<ev_cpp.C> implementation file that contains libev proper and is compiled:	4120	And a F<ev_cpp.C> implementation file that contains libev proper and is compiled:
…		…
4346	maintainable.	4350	maintainable.
4347		4351
4348	And of course, some compiler warnings are just plain stupid, or simply	4352	And of course, some compiler warnings are just plain stupid, or simply
4349	wrong (because they don't actually warn about the condition their message	4353	wrong (because they don't actually warn about the condition their message
4350	seems to warn about). For example, certain older gcc versions had some	4354	seems to warn about). For example, certain older gcc versions had some
4351	warnings that resulted an extreme number of false positives. These have	4355	warnings that resulted in an extreme number of false positives. These have
4352	been fixed, but some people still insist on making code warn-free with	4356	been fixed, but some people still insist on making code warn-free with
4353	such buggy versions.	4357	such buggy versions.
4354		4358
4355	While libev is written to generate as few warnings as possible,	4359	While libev is written to generate as few warnings as possible,
4356	"warn-free" code is not a goal, and it is recommended not to build libev	4360	"warn-free" code is not a goal, and it is recommended not to build libev
…		…
4392	I suggest using suppression lists.	4396	I suggest using suppression lists.
4393		4397
4394		4398
4395	=head1 PORTABILITY NOTES	4399	=head1 PORTABILITY NOTES
4396		4400
		4401	=head2 GNU/LINUX 32 BIT LIMITATIONS
		4402
		4403	GNU/Linux is the only common platform that supports 64 bit file/large file
		4404	interfaces but I<disables> them by default.
		4405
		4406	That means that libev compiled in the default environment doesn't support
		4407	files larger than 2GiB or so, which mainly affects C<ev_stat> watchers.
		4408
		4409	Unfortunately, many programs try to work around this GNU/Linux issue
		4410	by enabling the large file API, which makes them incompatible with the
		4411	standard libev compiled for their system.
		4412
		4413	Likewise, libev cannot enable the large file API itself as this would
		4414	suddenly make it incompatible to the default compile time environment,
		4415	i.e. all programs not using special compile switches.
		4416
		4417	=head2 OS/X AND DARWIN BUGS
		4418
		4419	The whole thing is a bug if you ask me - basically any system interface
		4420	you touch is broken, whether it is locales, poll, kqueue or even the
		4421	OpenGL drivers.
		4422
		4423	=head3 C<kqueue> is buggy
		4424
		4425	The kqueue syscall is broken in all known versions - most versions support
		4426	only sockets, many support pipes.
		4427
		4428	=head3 C<poll> is buggy
		4429
		4430	Instead of fixing C<kqueue>, Apple replaced their (working) C<poll>
		4431	implementation by something calling C<kqueue> internally around the 10.5.6
		4432	release, so now C<kqueue> I<and> C<poll> are broken.
		4433
		4434	Libev tries to work around this by neither using C<kqueue> nor C<poll> by
		4435	default on this rotten platform, but of course you cna still ask for them
		4436	when creating a loop.
		4437
		4438	=head3 C<select> is buggy
		4439
		4440	All that's left is C<select>, and of course Apple found a way to fuck this
		4441	one up as well: On OS/X, C<select> actively limits the number of file
		4442	descriptors you can pass in to 1024 - your program suddenyl crashes when
		4443	you use more.
		4444
		4445	There is an undocumented "workaround" for this - defining
		4446	C<_DARWIN_UNLIMITED_SELECT>, which libev tries to use, so select I<should>
		4447	work on OS/X.
		4448
		4449	=head2 SOLARIS PROBLEMS AND WORKAROUNDS
		4450
		4451	=head3 C<errno> reentrancy
		4452
		4453	The default compile environment on Solaris is unfortunately so
		4454	thread-unsafe that you can't even use components/libraries compiled
		4455	without C<-D_REENTRANT> (as long as they use C<errno>), which, of course,
		4456	isn't defined by default.
		4457
		4458	If you want to use libev in threaded environments you have to make sure
		4459	it's compiled with C<_REENTRANT> defined.
		4460
		4461	=head3 Event port backend
		4462
		4463	The scalable event interface for Solaris is called "event ports". Unfortunately,
		4464	this mechanism is very buggy. If you run into high CPU usage, your program
		4465	freezes or you get a large number of spurious wakeups, make sure you have
		4466	all the relevant and latest kernel patches applied. No, I don't know which
		4467	ones, but there are multiple ones.
		4468
		4469	If you can't get it to work, you can try running the program with
		4470	C<LIBEV_FLAGS=3> to only allow C<poll> and C<select> backends.
		4471
		4472	=head2 AIX POLL BUG
		4473
		4474	AIX unfortunately has a broken C<poll.h> header. Libev works around
		4475	this by trying to avoid the poll backend altogether (i.e. it's not even
		4476	compiled in), which normally isn't a big problem as C<select> works fine
		4477	with large bitsets, and AIX is dead anyway.
		4478
4397	=head2 WIN32 PLATFORM LIMITATIONS AND WORKAROUNDS	4479	=head2 WIN32 PLATFORM LIMITATIONS AND WORKAROUNDS
		4480
		4481	=head3 General issues
4398		4482
4399	Win32 doesn't support any of the standards (e.g. POSIX) that libev	4483	Win32 doesn't support any of the standards (e.g. POSIX) that libev
4400	requires, and its I/O model is fundamentally incompatible with the POSIX	4484	requires, and its I/O model is fundamentally incompatible with the POSIX
4401	model. Libev still offers limited functionality on this platform in	4485	model. Libev still offers limited functionality on this platform in
4402	the form of the C<EVBACKEND_SELECT> backend, and only supports socket	4486	the form of the C<EVBACKEND_SELECT> backend, and only supports socket
4403	descriptors. This only applies when using Win32 natively, not when using	4487	descriptors. This only applies when using Win32 natively, not when using
4404	e.g. cygwin.	4488	e.g. cygwin. Actually, it only applies to the microsofts own compilers,
		4489	as every compielr comes with a slightly differently broken/incompatible
		4490	environment.
4405		4491
4406	Lifting these limitations would basically require the full	4492	Lifting these limitations would basically require the full
4407	re-implementation of the I/O system. If you are into these kinds of	4493	re-implementation of the I/O system. If you are into this kind of thing,
4408	things, then note that glib does exactly that for you in a very portable	4494	then note that glib does exactly that for you in a very portable way (note
4409	way (note also that glib is the slowest event library known to man).	4495	also that glib is the slowest event library known to man).
4410		4496
4411	There is no supported compilation method available on windows except	4497	There is no supported compilation method available on windows except
4412	embedding it into other applications.	4498	embedding it into other applications.
4413		4499
4414	Sensible signal handling is officially unsupported by Microsoft - libev	4500	Sensible signal handling is officially unsupported by Microsoft - libev
…		…
4442	you do I<not> compile the F<ev.c> or any other embedded source files!):	4528	you do I<not> compile the F<ev.c> or any other embedded source files!):
4443		4529
4444	#include "evwrap.h"	4530	#include "evwrap.h"
4445	#include "ev.c"	4531	#include "ev.c"
4446		4532
4447	=over 4
4448
4449	=item The winsocket select function	4533	=head3 The winsocket C<select> function
4450		4534
4451	The winsocket C<select> function doesn't follow POSIX in that it	4535	The winsocket C<select> function doesn't follow POSIX in that it
4452	requires socket I<handles> and not socket I<file descriptors> (it is	4536	requires socket I<handles> and not socket I<file descriptors> (it is
4453	also extremely buggy). This makes select very inefficient, and also	4537	also extremely buggy). This makes select very inefficient, and also
4454	requires a mapping from file descriptors to socket handles (the Microsoft	4538	requires a mapping from file descriptors to socket handles (the Microsoft
…		…
4463	#define EV_SELECT_IS_WINSOCKET 1 /* forces EV_SELECT_USE_FD_SET, too */	4547	#define EV_SELECT_IS_WINSOCKET 1 /* forces EV_SELECT_USE_FD_SET, too */
4464		4548
4465	Note that winsockets handling of fd sets is O(n), so you can easily get a	4549	Note that winsockets handling of fd sets is O(n), so you can easily get a
4466	complexity in the O(n²) range when using win32.	4550	complexity in the O(n²) range when using win32.
4467		4551
4468	=item Limited number of file descriptors	4552	=head3 Limited number of file descriptors
4469		4553
4470	Windows has numerous arbitrary (and low) limits on things.	4554	Windows has numerous arbitrary (and low) limits on things.
4471		4555
4472	Early versions of winsocket's select only supported waiting for a maximum	4556	Early versions of winsocket's select only supported waiting for a maximum
4473	of C<64> handles (probably owning to the fact that all windows kernels	4557	of C<64> handles (probably owning to the fact that all windows kernels
…		…
4488	runtime libraries. This might get you to about C<512> or C<2048> sockets	4572	runtime libraries. This might get you to about C<512> or C<2048> sockets
4489	(depending on windows version and/or the phase of the moon). To get more,	4573	(depending on windows version and/or the phase of the moon). To get more,
4490	you need to wrap all I/O functions and provide your own fd management, but	4574	you need to wrap all I/O functions and provide your own fd management, but
4491	the cost of calling select (O(n²)) will likely make this unworkable.	4575	the cost of calling select (O(n²)) will likely make this unworkable.
4492		4576
4493	=back
4494
4495	=head2 PORTABILITY REQUIREMENTS	4577	=head2 PORTABILITY REQUIREMENTS
4496		4578
4497	In addition to a working ISO-C implementation and of course the	4579	In addition to a working ISO-C implementation and of course the
4498	backend-specific APIs, libev relies on a few additional extensions:	4580	backend-specific APIs, libev relies on a few additional extensions:
4499		4581
…		…
4619	involves iterating over all running async watchers or all signal numbers.	4701	involves iterating over all running async watchers or all signal numbers.
4620		4702
4621	=back	4703	=back
4622		4704
4623		4705
		4706	=head1 PORTING FROM LIBEV 3.X TO 4.X
		4707
		4708	The major version 4 introduced some minor incompatible changes to the API.
		4709
		4710	At the moment, the C<ev.h> header file tries to implement superficial
		4711	compatibility, so most programs should still compile. Those might be
		4712	removed in later versions of libev, so better update early than late.
		4713
		4714	=over 4
		4715
		4716	=item C<ev_loop_count> renamed to C<ev_iteration>
		4717
		4718	=item C<ev_loop_depth> renamed to C<ev_depth>
		4719
		4720	=item C<ev_loop_verify> renamed to C<ev_verify>
		4721
		4722	Most functions working on C<struct ev_loop> objects don't have an
		4723	C<ev_loop_> prefix, so it was removed. Note that C<ev_loop_fork> is
		4724	still called C<ev_loop_fork> because it would otherwise clash with the
		4725	C<ev_fork> typedef.
		4726
		4727	=item C<EV_TIMEOUT> renamed to C<EV_TIMER> in C<revents>
		4728
		4729	This is a simple rename - all other watcher types use their name
		4730	as revents flag, and now C<ev_timer> does, too.
		4731
		4732	Both C<EV_TIMER> and C<EV_TIMEOUT> symbols were present in 3.x versions
		4733	and continue to be present for the foreseeable future, so this is mostly a
		4734	documentation change.
		4735
		4736	=item C<EV_MINIMAL> mechanism replaced by C<EV_FEATURES>
		4737
		4738	The preprocessor symbol C<EV_MINIMAL> has been replaced by a different
		4739	mechanism, C<EV_FEATURES>. Programs using C<EV_MINIMAL> usually compile
		4740	and work, but the library code will of course be larger.
		4741
		4742	=back
		4743
		4744
4624	=head1 GLOSSARY	4745	=head1 GLOSSARY
4625		4746
4626	=over 4	4747	=over 4
4627		4748
4628	=item active	4749	=item active
…		…
4649	A change of state of some external event, such as data now being available	4770	A change of state of some external event, such as data now being available
4650	for reading on a file descriptor, time having passed or simply not having	4771	for reading on a file descriptor, time having passed or simply not having
4651	any other events happening anymore.	4772	any other events happening anymore.
4652		4773
4653	In libev, events are represented as single bits (such as C<EV_READ> or	4774	In libev, events are represented as single bits (such as C<EV_READ> or
4654	C<EV_TIMEOUT>).	4775	C<EV_TIMER>).
4655		4776
4656	=item event library	4777	=item event library
4657		4778
4658	A software package implementing an event model and loop.	4779	A software package implementing an event model and loop.
4659		4780

Diff Legend

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

Comparing libev/ev.pod (file contents): Revision 1.285 by root, Tue Mar 16 00:20:17 2010 UTC vs. Revision 1.303 by root, Thu Oct 14 04:29:34 2010 UTC

Diff Legend

Comparing libev/ev.pod (file contents):
Revision 1.285 by root, Tue Mar 16 00:20:17 2010 UTC vs.
Revision 1.303 by root, Thu Oct 14 04:29:34 2010 UTC