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

Comparing libev/ev.pod (file contents):
Revision 1.199 by root, Thu Oct 23 07:18:21 2008 UTC vs.
Revision 1.226 by root, Wed Mar 4 12:51:37 2009 UTC

…		…
9	=head2 EXAMPLE PROGRAM	9	=head2 EXAMPLE PROGRAM
10		10
11	// a single header file is required	11	// a single header file is required
12	#include <ev.h>	12	#include <ev.h>
13		13
		14	#include <stdio.h> // for puts
		15
14	// every watcher type has its own typedef'd struct	16	// every watcher type has its own typedef'd struct
15	// with the name ev_<type>	17	// with the name ev_TYPE
16	ev_io stdin_watcher;	18	ev_io stdin_watcher;
17	ev_timer timeout_watcher;	19	ev_timer timeout_watcher;
18		20
19	// all watcher callbacks have a similar signature	21	// all watcher callbacks have a similar signature
20	// this callback is called when data is readable on stdin	22	// this callback is called when data is readable on stdin
…		…
41		43
42	int	44	int
43	main (void)	45	main (void)
44	{	46	{
45	// use the default event loop unless you have special needs	47	// use the default event loop unless you have special needs
46	ev_loop *loop = ev_default_loop (0);	48	struct ev_loop *loop = ev_default_loop (0);
47		49
48	// initialise an io watcher, then start it	50	// initialise an io watcher, then start it
49	// this one will watch for stdin to become readable	51	// this one will watch for stdin to become readable
50	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);
51	ev_io_start (loop, &stdin_watcher);	53	ev_io_start (loop, &stdin_watcher);
…		…
276		278
277	=back	279	=back
278		280
279	=head1 FUNCTIONS CONTROLLING THE EVENT LOOP	281	=head1 FUNCTIONS CONTROLLING THE EVENT LOOP
280		282
281	An event loop is described by a C<ev_loop *>. The library knows two	283	An event loop is described by a C<struct ev_loop *> (the C<struct>
282	types of such loops, the I<default> loop, which supports signals and child	284	is I<not> optional in this case, as there is also an C<ev_loop>
283	events, and dynamically created loops which do not.	285	I<function>).
		286
		287	The library knows two types of such loops, the I<default> loop, which
		288	supports signals and child events, and dynamically created loops which do
		289	not.
284		290
285	=over 4	291	=over 4
286		292
287	=item struct ev_loop *ev_default_loop (unsigned int flags)	293	=item struct ev_loop *ev_default_loop (unsigned int flags)
288		294
…		…
294	If you don't know what event loop to use, use the one returned from this	300	If you don't know what event loop to use, use the one returned from this
295	function.	301	function.
296		302
297	Note that this function is I<not> thread-safe, so if you want to use it	303	Note that this function is I<not> thread-safe, so if you want to use it
298	from multiple threads, you have to lock (note also that this is unlikely,	304	from multiple threads, you have to lock (note also that this is unlikely,
299	as loops cannot bes hared easily between threads anyway).	305	as loops cannot be shared easily between threads anyway).
300		306
301	The default loop is the only loop that can handle C<ev_signal> and	307	The default loop is the only loop that can handle C<ev_signal> and
302	C<ev_child> watchers, and to do this, it always registers a handler	308	C<ev_child> watchers, and to do this, it always registers a handler
303	for C<SIGCHLD>. If this is a problem for your application you can either	309	for C<SIGCHLD>. If this is a problem for your application you can either
304	create a dynamic loop with C<ev_loop_new> that doesn't do that, or you	310	create a dynamic loop with C<ev_loop_new> that doesn't do that, or you
…		…
380	=item C<EVBACKEND_EPOLL> (value 4, Linux)	386	=item C<EVBACKEND_EPOLL> (value 4, Linux)
381		387
382	For few fds, this backend is a bit little slower than poll and select,	388	For few fds, this backend is a bit little slower than poll and select,
383	but it scales phenomenally better. While poll and select usually scale	389	but it scales phenomenally better. While poll and select usually scale
384	like O(total_fds) where n is the total number of fds (or the highest fd),	390	like O(total_fds) where n is the total number of fds (or the highest fd),
385	epoll scales either O(1) or O(active_fds). The epoll design has a number	391	epoll scales either O(1) or O(active_fds).
386	of shortcomings, such as silently dropping events in some hard-to-detect	392
387	cases and requiring a system call per fd change, no fork support and bad	393	The epoll mechanism deserves honorable mention as the most misdesigned
388	support for dup.	394	of the more advanced event mechanisms: mere annoyances include silently
		395	dropping file descriptors, requiring a system call per change per file
		396	descriptor (and unnecessary guessing of parameters), problems with dup and
		397	so on. The biggest issue is fork races, however - if a program forks then
		398	I<both> parent and child process have to recreate the epoll set, which can
		399	take considerable time (one syscall per file descriptor) and is of course
		400	hard to detect.
		401
		402	Epoll is also notoriously buggy - embedding epoll fds I<should> work, but
		403	of course I<doesn't>, and epoll just loves to report events for totally
		404	I<different> file descriptors (even already closed ones, so one cannot
		405	even remove them from the set) than registered in the set (especially
		406	on SMP systems). Libev tries to counter these spurious notifications by
		407	employing an additional generation counter and comparing that against the
		408	events to filter out spurious ones, recreating the set when required.
389		409
390	While stopping, setting and starting an I/O watcher in the same iteration	410	While stopping, setting and starting an I/O watcher in the same iteration
391	will result in some caching, there is still a system call per such incident	411	will result in some caching, there is still a system call per such
392	(because the fd could point to a different file description now), so its	412	incident (because the same I<file descriptor> could point to a different
393	best to avoid that. Also, C<dup ()>'ed file descriptors might not work	413	I<file description> now), so its best to avoid that. Also, C<dup ()>'ed
394	very well if you register events for both fds.	414	file descriptors might not work very well if you register events for both
395		415	file descriptors.
396	Please note that epoll sometimes generates spurious notifications, so you
397	need to use non-blocking I/O or other means to avoid blocking when no data
398	(or space) is available.
399		416
400	Best performance from this backend is achieved by not unregistering all	417	Best performance from this backend is achieved by not unregistering all
401	watchers for a file descriptor until it has been closed, if possible,	418	watchers for a file descriptor until it has been closed, if possible,
402	i.e. keep at least one watcher active per fd at all times. Stopping and	419	i.e. keep at least one watcher active per fd at all times. Stopping and
403	starting a watcher (without re-setting it) also usually doesn't cause	420	starting a watcher (without re-setting it) also usually doesn't cause
404	extra overhead.	421	extra overhead. A fork can both result in spurious notifications as well
		422	as in libev having to destroy and recreate the epoll object, which can
		423	take considerable time and thus should be avoided.
		424
		425	All this means that, in practice, C<EVBACKEND_SELECT> can be as fast or
		426	faster than epoll for maybe up to a hundred file descriptors, depending on
		427	the usage. So sad.
405		428
406	While nominally embeddable in other event loops, this feature is broken in	429	While nominally embeddable in other event loops, this feature is broken in
407	all kernel versions tested so far.	430	all kernel versions tested so far.
408		431
409	This backend maps C<EV_READ> and C<EV_WRITE> in the same way as	432	This backend maps C<EV_READ> and C<EV_WRITE> in the same way as
410	C<EVBACKEND_POLL>.	433	C<EVBACKEND_POLL>.
411		434
412	=item C<EVBACKEND_KQUEUE> (value 8, most BSD clones)	435	=item C<EVBACKEND_KQUEUE> (value 8, most BSD clones)
413		436
414	Kqueue deserves special mention, as at the time of this writing, it was	437	Kqueue deserves special mention, as at the time of this writing, it
415	broken on all BSDs except NetBSD (usually it doesn't work reliably with	438	was broken on all BSDs except NetBSD (usually it doesn't work reliably
416	anything but sockets and pipes, except on Darwin, where of course it's	439	with anything but sockets and pipes, except on Darwin, where of course
417	completely useless). For this reason it's not being "auto-detected" unless	440	it's completely useless). Unlike epoll, however, whose brokenness
418	you explicitly specify it in the flags (i.e. using C<EVBACKEND_KQUEUE>) or	441	is by design, these kqueue bugs can (and eventually will) be fixed
419	libev was compiled on a known-to-be-good (-enough) system like NetBSD.	442	without API changes to existing programs. For this reason it's not being
		443	"auto-detected" unless you explicitly specify it in the flags (i.e. using
		444	C<EVBACKEND_KQUEUE>) or libev was compiled on a known-to-be-good (-enough)
		445	system like NetBSD.
420		446
421	You still can embed kqueue into a normal poll or select backend and use it	447	You still can embed kqueue into a normal poll or select backend and use it
422	only for sockets (after having made sure that sockets work with kqueue on	448	only for sockets (after having made sure that sockets work with kqueue on
423	the target platform). See C<ev_embed> watchers for more info.	449	the target platform). See C<ev_embed> watchers for more info.
424		450
425	It scales in the same way as the epoll backend, but the interface to the	451	It scales in the same way as the epoll backend, but the interface to the
426	kernel is more efficient (which says nothing about its actual speed, of	452	kernel is more efficient (which says nothing about its actual speed, of
427	course). While stopping, setting and starting an I/O watcher does never	453	course). While stopping, setting and starting an I/O watcher does never
428	cause an extra system call as with C<EVBACKEND_EPOLL>, it still adds up to	454	cause an extra system call as with C<EVBACKEND_EPOLL>, it still adds up to
429	two event changes per incident. Support for C<fork ()> is very bad and it	455	two event changes per incident. Support for C<fork ()> is very bad (but
430	drops fds silently in similarly hard-to-detect cases.	456	sane, unlike epoll) and it drops fds silently in similarly hard-to-detect
		457	cases
431		458
432	This backend usually performs well under most conditions.	459	This backend usually performs well under most conditions.
433		460
434	While nominally embeddable in other event loops, this doesn't work	461	While nominally embeddable in other event loops, this doesn't work
435	everywhere, so you might need to test for this. And since it is broken	462	everywhere, so you might need to test for this. And since it is broken
436	almost everywhere, you should only use it when you have a lot of sockets	463	almost everywhere, you should only use it when you have a lot of sockets
437	(for which it usually works), by embedding it into another event loop	464	(for which it usually works), by embedding it into another event loop
438	(e.g. C<EVBACKEND_SELECT> or C<EVBACKEND_POLL>) and, did I mention it,	465	(e.g. C<EVBACKEND_SELECT> or C<EVBACKEND_POLL> (but C<poll> is of course
439	using it only for sockets.	466	also broken on OS X)) and, did I mention it, using it only for sockets.
440		467
441	This backend maps C<EV_READ> into an C<EVFILT_READ> kevent with	468	This backend maps C<EV_READ> into an C<EVFILT_READ> kevent with
442	C<NOTE_EOF>, and C<EV_WRITE> into an C<EVFILT_WRITE> kevent with	469	C<NOTE_EOF>, and C<EV_WRITE> into an C<EVFILT_WRITE> kevent with
443	C<NOTE_EOF>.	470	C<NOTE_EOF>.
444		471
…		…
464	might perform better.	491	might perform better.
465		492
466	On the positive side, with the exception of the spurious readiness	493	On the positive side, with the exception of the spurious readiness
467	notifications, this backend actually performed fully to specification	494	notifications, this backend actually performed fully to specification
468	in all tests and is fully embeddable, which is a rare feat among the	495	in all tests and is fully embeddable, which is a rare feat among the
469	OS-specific backends.	496	OS-specific backends (I vastly prefer correctness over speed hacks).
470		497
471	This backend maps C<EV_READ> and C<EV_WRITE> in the same way as	498	This backend maps C<EV_READ> and C<EV_WRITE> in the same way as
472	C<EVBACKEND_POLL>.	499	C<EVBACKEND_POLL>.
473		500
474	=item C<EVBACKEND_ALL>	501	=item C<EVBACKEND_ALL>
…		…
527	responsibility to either stop all watchers cleanly yourself I<before>	554	responsibility to either stop all watchers cleanly yourself I<before>
528	calling this function, or cope with the fact afterwards (which is usually	555	calling this function, or cope with the fact afterwards (which is usually
529	the easiest thing, you can just ignore the watchers and/or C<free ()> them	556	the easiest thing, you can just ignore the watchers and/or C<free ()> them
530	for example).	557	for example).
531		558
532	Note that certain global state, such as signal state, will not be freed by	559	Note that certain global state, such as signal state (and installed signal
533	this function, and related watchers (such as signal and child watchers)	560	handlers), will not be freed by this function, and related watchers (such
534	would need to be stopped manually.	561	as signal and child watchers) would need to be stopped manually.
535		562
536	In general it is not advisable to call this function except in the	563	In general it is not advisable to call this function except in the
537	rare occasion where you really need to free e.g. the signal handling	564	rare occasion where you really need to free e.g. the signal handling
538	pipe fds. If you need dynamically allocated loops it is better to use	565	pipe fds. If you need dynamically allocated loops it is better to use
539	C<ev_loop_new> and C<ev_loop_destroy>).	566	C<ev_loop_new> and C<ev_loop_destroy>).
…		…
631	the loop.	658	the loop.
632		659
633	A flags value of C<EVLOOP_ONESHOT> will look for new events (waiting if	660	A flags value of C<EVLOOP_ONESHOT> will look for new events (waiting if
634	necessary) and will handle those and any already outstanding ones. It	661	necessary) and will handle those and any already outstanding ones. It
635	will block your process until at least one new event arrives (which could	662	will block your process until at least one new event arrives (which could
636	be an event internal to libev itself, so there is no guarentee that a	663	be an event internal to libev itself, so there is no guarantee that a
637	user-registered callback will be called), and will return after one	664	user-registered callback will be called), and will return after one
638	iteration of the loop.	665	iteration of the loop.
639		666
640	This is useful if you are waiting for some external event in conjunction	667	This is useful if you are waiting for some external event in conjunction
641	with something not expressible using other libev watchers (i.e. "roll your	668	with something not expressible using other libev watchers (i.e. "roll your
…		…
768	they fire on, say, one-second boundaries only.	795	they fire on, say, one-second boundaries only.
769		796
770	=item ev_loop_verify (loop)	797	=item ev_loop_verify (loop)
771		798
772	This function only does something when C<EV_VERIFY> support has been	799	This function only does something when C<EV_VERIFY> support has been
773	compiled in. which is the default for non-minimal builds. It tries to go	800	compiled in, which is the default for non-minimal builds. It tries to go
774	through all internal structures and checks them for validity. If anything	801	through all internal structures and checks them for validity. If anything
775	is found to be inconsistent, it will print an error message to standard	802	is found to be inconsistent, it will print an error message to standard
776	error and call C<abort ()>.	803	error and call C<abort ()>.
777		804
778	This can be used to catch bugs inside libev itself: under normal	805	This can be used to catch bugs inside libev itself: under normal
…		…
781		808
782	=back	809	=back
783		810
784		811
785	=head1 ANATOMY OF A WATCHER	812	=head1 ANATOMY OF A WATCHER
		813
		814	In the following description, uppercase C<TYPE> in names stands for the
		815	watcher type, e.g. C<ev_TYPE_start> can mean C<ev_timer_start> for timer
		816	watchers and C<ev_io_start> for I/O watchers.
786		817
787	A watcher is a structure that you create and register to record your	818	A watcher is a structure that you create and register to record your
788	interest in some event. For instance, if you want to wait for STDIN to	819	interest in some event. For instance, if you want to wait for STDIN to
789	become readable, you would create an C<ev_io> watcher for that:	820	become readable, you would create an C<ev_io> watcher for that:
790		821
…		…
793	ev_io_stop (w);	824	ev_io_stop (w);
794	ev_unloop (loop, EVUNLOOP_ALL);	825	ev_unloop (loop, EVUNLOOP_ALL);
795	}	826	}
796		827
797	struct ev_loop *loop = ev_default_loop (0);	828	struct ev_loop *loop = ev_default_loop (0);
		829
798	ev_io stdin_watcher;	830	ev_io stdin_watcher;
		831
799	ev_init (&stdin_watcher, my_cb);	832	ev_init (&stdin_watcher, my_cb);
800	ev_io_set (&stdin_watcher, STDIN_FILENO, EV_READ);	833	ev_io_set (&stdin_watcher, STDIN_FILENO, EV_READ);
801	ev_io_start (loop, &stdin_watcher);	834	ev_io_start (loop, &stdin_watcher);
		835
802	ev_loop (loop, 0);	836	ev_loop (loop, 0);
803		837
804	As you can see, you are responsible for allocating the memory for your	838	As you can see, you are responsible for allocating the memory for your
805	watcher structures (and it is usually a bad idea to do this on the stack,	839	watcher structures (and it is I<usually> a bad idea to do this on the
806	although this can sometimes be quite valid).	840	stack).
		841
		842	Each watcher has an associated watcher structure (called C<struct ev_TYPE>
		843	or simply C<ev_TYPE>, as typedefs are provided for all watcher structs).
807		844
808	Each watcher structure must be initialised by a call to C<ev_init	845	Each watcher structure must be initialised by a call to C<ev_init
809	(watcher *, callback)>, which expects a callback to be provided. This	846	(watcher *, callback)>, which expects a callback to be provided. This
810	callback gets invoked each time the event occurs (or, in the case of I/O	847	callback gets invoked each time the event occurs (or, in the case of I/O
811	watchers, each time the event loop detects that the file descriptor given	848	watchers, each time the event loop detects that the file descriptor given
812	is readable and/or writable).	849	is readable and/or writable).
813		850
814	Each watcher type has its own C<< ev_<type>_set (watcher *, ...) >> macro	851	Each watcher type further has its own C<< ev_TYPE_set (watcher *, ...) >>
815	with arguments specific to this watcher type. There is also a macro	852	macro to configure it, with arguments specific to the watcher type. There
816	to combine initialisation and setting in one call: C<< ev_<type>_init	853	is also a macro to combine initialisation and setting in one call: C<<
817	(watcher *, callback, ...) >>.	854	ev_TYPE_init (watcher *, callback, ...) >>.
818		855
819	To make the watcher actually watch out for events, you have to start it	856	To make the watcher actually watch out for events, you have to start it
820	with a watcher-specific start function (C<< ev_<type>_start (loop, watcher	857	with a watcher-specific start function (C<< ev_TYPE_start (loop, watcher
821	*) >>), and you can stop watching for events at any time by calling the	858	*) >>), and you can stop watching for events at any time by calling the
822	corresponding stop function (C<< ev_<type>_stop (loop, watcher *) >>.	859	corresponding stop function (C<< ev_TYPE_stop (loop, watcher *) >>.
823		860
824	As long as your watcher is active (has been started but not stopped) you	861	As long as your watcher is active (has been started but not stopped) you
825	must not touch the values stored in it. Most specifically you must never	862	must not touch the values stored in it. Most specifically you must never
826	reinitialise it or call its C<set> macro.	863	reinitialise it or call its C<ev_TYPE_set> macro.
827		864
828	Each and every callback receives the event loop pointer as first, the	865	Each and every callback receives the event loop pointer as first, the
829	registered watcher structure as second, and a bitset of received events as	866	registered watcher structure as second, and a bitset of received events as
830	third argument.	867	third argument.
831		868
…		…
912		949
913	=back	950	=back
914		951
915	=head2 GENERIC WATCHER FUNCTIONS	952	=head2 GENERIC WATCHER FUNCTIONS
916		953
917	In the following description, C<TYPE> stands for the watcher type,
918	e.g. C<timer> for C<ev_timer> watchers and C<io> for C<ev_io> watchers.
919
920	=over 4	954	=over 4
921		955
922	=item C<ev_init> (ev_TYPE *watcher, callback)	956	=item C<ev_init> (ev_TYPE *watcher, callback)
923		957
924	This macro initialises the generic portion of a watcher. The contents	958	This macro initialises the generic portion of a watcher. The contents
…		…
1032	The default priority used by watchers when no priority has been set is	1066	The default priority used by watchers when no priority has been set is
1033	always C<0>, which is supposed to not be too high and not be too low :).	1067	always C<0>, which is supposed to not be too high and not be too low :).
1034		1068
1035	Setting a priority outside the range of C<EV_MINPRI> to C<EV_MAXPRI> is	1069	Setting a priority outside the range of C<EV_MINPRI> to C<EV_MAXPRI> is
1036	fine, as long as you do not mind that the priority value you query might	1070	fine, as long as you do not mind that the priority value you query might
1037	or might not have been adjusted to be within valid range.	1071	or might not have been clamped to the valid range.
1038		1072
1039	=item ev_invoke (loop, ev_TYPE *watcher, int revents)	1073	=item ev_invoke (loop, ev_TYPE *watcher, int revents)
1040		1074
1041	Invoke the C<watcher> with the given C<loop> and C<revents>. Neither	1075	Invoke the C<watcher> with the given C<loop> and C<revents>. Neither
1042	C<loop> nor C<revents> need to be valid as long as the watcher callback	1076	C<loop> nor C<revents> need to be valid as long as the watcher callback
…		…
1387	else	1421	else
1388	{	1422	{
1389	// callback was invoked, but there was some activity, re-arm	1423	// callback was invoked, but there was some activity, re-arm
1390	// the watcher to fire in last_activity + 60, which is	1424	// the watcher to fire in last_activity + 60, which is
1391	// guaranteed to be in the future, so "again" is positive:	1425	// guaranteed to be in the future, so "again" is positive:
1392	w->again = timeout - now;	1426	w->repeat = timeout - now;
1393	ev_timer_again (EV_A_ w);	1427	ev_timer_again (EV_A_ w);
1394	}	1428	}
1395	}	1429	}
1396		1430
1397	To summarise the callback: first calculate the real timeout (defined	1431	To summarise the callback: first calculate the real timeout (defined
…		…
1426		1460
1427	Changing the timeout is trivial as well (if it isn't hard-coded in the	1461	Changing the timeout is trivial as well (if it isn't hard-coded in the
1428	callback :) - just change the timeout and invoke the callback, which will	1462	callback :) - just change the timeout and invoke the callback, which will
1429	fix things for you.	1463	fix things for you.
1430		1464
1431	=item 4. Whee, use a double-linked list for your timeouts.	1465	=item 4. Wee, just use a double-linked list for your timeouts.
1432		1466
1433	If there is not one request, but many thousands, all employing some kind	1467	If there is not one request, but many thousands (millions...), all
1434	of timeout with the same timeout value, then one can do even better:	1468	employing some kind of timeout with the same timeout value, then one can
		1469	do even better:
1435		1470
1436	When starting the timeout, calculate the timeout value and put the timeout	1471	When starting the timeout, calculate the timeout value and put the timeout
1437	at the I<end> of the list.	1472	at the I<end> of the list.
1438		1473
1439	Then use an C<ev_timer> to fire when the timeout at the I<beginning> of	1474	Then use an C<ev_timer> to fire when the timeout at the I<beginning> of
…		…
1448	complication, and having to use a constant timeout. The constant timeout	1483	complication, and having to use a constant timeout. The constant timeout
1449	ensures that the list stays sorted.	1484	ensures that the list stays sorted.
1450		1485
1451	=back	1486	=back
1452		1487
1453	So what method is the best?	1488	So which method the best?
1454		1489
1455	The method #2 is a simple no-brain-required solution that is adequate in	1490	Method #2 is a simple no-brain-required solution that is adequate in most
1456	most situations. Method #3 requires a bit more thinking, but handles many	1491	situations. Method #3 requires a bit more thinking, but handles many cases
1457	cases better, and isn't very complicated either. In most case, choosing	1492	better, and isn't very complicated either. In most case, choosing either
1458	either one is fine.	1493	one is fine, with #3 being better in typical situations.
1459		1494
1460	Method #1 is almost always a bad idea, and buys you nothing. Method #4 is	1495	Method #1 is almost always a bad idea, and buys you nothing. Method #4 is
1461	rather complicated, but extremely efficient, something that really pays	1496	rather complicated, but extremely efficient, something that really pays
1462	off after the first or so million of active timers, i.e. it's usually	1497	off after the first million or so of active timers, i.e. it's usually
1463	overkill :)	1498	overkill :)
1464		1499
1465	=head3 The special problem of time updates	1500	=head3 The special problem of time updates
1466		1501
1467	Establishing the current time is a costly operation (it usually takes at	1502	Establishing the current time is a costly operation (it usually takes at
…		…
1584		1619
1585	=over 4	1620	=over 4
1586		1621
1587	=item ev_periodic_init (ev_periodic *, callback, ev_tstamp at, ev_tstamp interval, reschedule_cb)	1622	=item ev_periodic_init (ev_periodic *, callback, ev_tstamp at, ev_tstamp interval, reschedule_cb)
1588		1623
1589	=item ev_periodic_set (ev_periodic *, ev_tstamp after, ev_tstamp repeat, reschedule_cb)	1624	=item ev_periodic_set (ev_periodic *, ev_tstamp at, ev_tstamp interval, reschedule_cb)
1590		1625
1591	Lots of arguments, lets sort it out... There are basically three modes of	1626	Lots of arguments, lets sort it out... There are basically three modes of
1592	operation, and we will explain them from simplest to most complex:	1627	operation, and we will explain them from simplest to most complex:
1593		1628
1594	=over 4	1629	=over 4
…		…
1636	ignored. Instead, each time the periodic watcher gets scheduled, the	1671	ignored. Instead, each time the periodic watcher gets scheduled, the
1637	reschedule callback will be called with the watcher as first, and the	1672	reschedule callback will be called with the watcher as first, and the
1638	current time as second argument.	1673	current time as second argument.
1639		1674
1640	NOTE: I<This callback MUST NOT stop or destroy any periodic watcher,	1675	NOTE: I<This callback MUST NOT stop or destroy any periodic watcher,
1641	ever, or make ANY event loop modifications whatsoever>.	1676	ever, or make ANY other event loop modifications whatsoever>.
1642		1677
1643	If you need to stop it, return C<now + 1e30> (or so, fudge fudge) and stop	1678	If you need to stop it, return C<now + 1e30> (or so, fudge fudge) and stop
1644	it afterwards (e.g. by starting an C<ev_prepare> watcher, which is the	1679	it afterwards (e.g. by starting an C<ev_prepare> watcher, which is the
1645	only event loop modification you are allowed to do).	1680	only event loop modification you are allowed to do).
1646		1681
…		…
1898		1933
1899		1934
1900	=head2 C<ev_stat> - did the file attributes just change?	1935	=head2 C<ev_stat> - did the file attributes just change?
1901		1936
1902	This watches a file system path for attribute changes. That is, it calls	1937	This watches a file system path for attribute changes. That is, it calls
1903	C<stat> regularly (or when the OS says it changed) and sees if it changed	1938	C<stat> on that path in regular intervals (or when the OS says it changed)
1904	compared to the last time, invoking the callback if it did.	1939	and sees if it changed compared to the last time, invoking the callback if
		1940	it did.
1905		1941
1906	The path does not need to exist: changing from "path exists" to "path does	1942	The path does not need to exist: changing from "path exists" to "path does
1907	not exist" is a status change like any other. The condition "path does	1943	not exist" is a status change like any other. The condition "path does not
1908	not exist" is signified by the C<st_nlink> field being zero (which is	1944	exist" (or more correctly "path cannot be stat'ed") is signified by the
1909	otherwise always forced to be at least one) and all the other fields of	1945	C<st_nlink> field being zero (which is otherwise always forced to be at
1910	the stat buffer having unspecified contents.	1946	least one) and all the other fields of the stat buffer having unspecified
		1947	contents.
1911		1948
1912	The path I<should> be absolute and I<must not> end in a slash. If it is	1949	The path I<must not> end in a slash or contain special components such as
		1950	C<.> or C<..>. The path I<should> be absolute: If it is relative and
1913	relative and your working directory changes, the behaviour is undefined.	1951	your working directory changes, then the behaviour is undefined.
1914		1952
1915	Since there is no standard kernel interface to do this, the portable	1953	Since there is no portable change notification interface available, the
1916	implementation simply calls C<stat (2)> regularly on the path to see if	1954	portable implementation simply calls C<stat(2)> regularly on the path
1917	it changed somehow. You can specify a recommended polling interval for	1955	to see if it changed somehow. You can specify a recommended polling
1918	this case. If you specify a polling interval of C<0> (highly recommended!)	1956	interval for this case. If you specify a polling interval of C<0> (highly
1919	then a I<suitable, unspecified default> value will be used (which	1957	recommended!) then a I<suitable, unspecified default> value will be used
1920	you can expect to be around five seconds, although this might change	1958	(which you can expect to be around five seconds, although this might
1921	dynamically). Libev will also impose a minimum interval which is currently	1959	change dynamically). Libev will also impose a minimum interval which is
1922	around C<0.1>, but thats usually overkill.	1960	currently around C<0.1>, but that's usually overkill.
1923		1961
1924	This watcher type is not meant for massive numbers of stat watchers,	1962	This watcher type is not meant for massive numbers of stat watchers,
1925	as even with OS-supported change notifications, this can be	1963	as even with OS-supported change notifications, this can be
1926	resource-intensive.	1964	resource-intensive.
1927		1965
1928	At the time of this writing, the only OS-specific interface implemented	1966	At the time of this writing, the only OS-specific interface implemented
1929	is the Linux inotify interface (implementing kqueue support is left as	1967	is the Linux inotify interface (implementing kqueue support is left as an
1930	an exercise for the reader. Note, however, that the author sees no way	1968	exercise for the reader. Note, however, that the author sees no way of
1931	of implementing C<ev_stat> semantics with kqueue).	1969	implementing C<ev_stat> semantics with kqueue, except as a hint).
1932		1970
1933	=head3 ABI Issues (Largefile Support)	1971	=head3 ABI Issues (Largefile Support)
1934		1972
1935	Libev by default (unless the user overrides this) uses the default	1973	Libev by default (unless the user overrides this) uses the default
1936	compilation environment, which means that on systems with large file	1974	compilation environment, which means that on systems with large file
1937	support disabled by default, you get the 32 bit version of the stat	1975	support disabled by default, you get the 32 bit version of the stat
1938	structure. When using the library from programs that change the ABI to	1976	structure. When using the library from programs that change the ABI to
1939	use 64 bit file offsets the programs will fail. In that case you have to	1977	use 64 bit file offsets the programs will fail. In that case you have to
1940	compile libev with the same flags to get binary compatibility. This is	1978	compile libev with the same flags to get binary compatibility. This is
1941	obviously the case with any flags that change the ABI, but the problem is	1979	obviously the case with any flags that change the ABI, but the problem is
1942	most noticeably disabled with ev_stat and large file support.	1980	most noticeably displayed with ev_stat and large file support.
1943		1981
1944	The solution for this is to lobby your distribution maker to make large	1982	The solution for this is to lobby your distribution maker to make large
1945	file interfaces available by default (as e.g. FreeBSD does) and not	1983	file interfaces available by default (as e.g. FreeBSD does) and not
1946	optional. Libev cannot simply switch on large file support because it has	1984	optional. Libev cannot simply switch on large file support because it has
1947	to exchange stat structures with application programs compiled using the	1985	to exchange stat structures with application programs compiled using the
1948	default compilation environment.	1986	default compilation environment.
1949		1987
1950	=head3 Inotify and Kqueue	1988	=head3 Inotify and Kqueue
1951		1989
1952	When C<inotify (7)> support has been compiled into libev (generally	1990	When C<inotify (7)> support has been compiled into libev and present at
1953	only available with Linux 2.6.25 or above due to bugs in earlier	1991	runtime, it will be used to speed up change detection where possible. The
1954	implementations) and present at runtime, it will be used to speed up	1992	inotify descriptor will be created lazily when the first C<ev_stat>
1955	change detection where possible. The inotify descriptor will be created	1993	watcher is being started.
1956	lazily when the first C<ev_stat> watcher is being started.
1957		1994
1958	Inotify presence does not change the semantics of C<ev_stat> watchers	1995	Inotify presence does not change the semantics of C<ev_stat> watchers
1959	except that changes might be detected earlier, and in some cases, to avoid	1996	except that changes might be detected earlier, and in some cases, to avoid
1960	making regular C<stat> calls. Even in the presence of inotify support	1997	making regular C<stat> calls. Even in the presence of inotify support
1961	there are many cases where libev has to resort to regular C<stat> polling,	1998	there are many cases where libev has to resort to regular C<stat> polling,
1962	but as long as the path exists, libev usually gets away without polling.	1999	but as long as kernel 2.6.25 or newer is used (2.6.24 and older have too
		2000	many bugs), the path exists (i.e. stat succeeds), and the path resides on
		2001	a local filesystem (libev currently assumes only ext2/3, jfs, reiserfs and
		2002	xfs are fully working) libev usually gets away without polling.
1963		2003
1964	There is no support for kqueue, as apparently it cannot be used to	2004	There is no support for kqueue, as apparently it cannot be used to
1965	implement this functionality, due to the requirement of having a file	2005	implement this functionality, due to the requirement of having a file
1966	descriptor open on the object at all times, and detecting renames, unlinks	2006	descriptor open on the object at all times, and detecting renames, unlinks
1967	etc. is difficult.	2007	etc. is difficult.
1968		2008
		2009	=head3 C<stat ()> is a synchronous operation
		2010
		2011	Libev doesn't normally do any kind of I/O itself, and so is not blocking
		2012	the process. The exception are C<ev_stat> watchers - those call C<stat
		2013	()>, which is a synchronous operation.
		2014
		2015	For local paths, this usually doesn't matter: unless the system is very
		2016	busy or the intervals between stat's are large, a stat call will be fast,
		2017	as the path data is usually in memory already (except when starting the
		2018	watcher).
		2019
		2020	For networked file systems, calling C<stat ()> can block an indefinite
		2021	time due to network issues, and even under good conditions, a stat call
		2022	often takes multiple milliseconds.
		2023
		2024	Therefore, it is best to avoid using C<ev_stat> watchers on networked
		2025	paths, although this is fully supported by libev.
		2026
1969	=head3 The special problem of stat time resolution	2027	=head3 The special problem of stat time resolution
1970		2028
1971	The C<stat ()> system call only supports full-second resolution portably, and	2029	The C<stat ()> system call only supports full-second resolution portably,
1972	even on systems where the resolution is higher, most file systems still	2030	and even on systems where the resolution is higher, most file systems
1973	only support whole seconds.	2031	still only support whole seconds.
1974		2032
1975	That means that, if the time is the only thing that changes, you can	2033	That means that, if the time is the only thing that changes, you can
1976	easily miss updates: on the first update, C<ev_stat> detects a change and	2034	easily miss updates: on the first update, C<ev_stat> detects a change and
1977	calls your callback, which does something. When there is another update	2035	calls your callback, which does something. When there is another update
1978	within the same second, C<ev_stat> will be unable to detect unless the	2036	within the same second, C<ev_stat> will be unable to detect unless the
…		…
2121		2179
2122	=head3 Watcher-Specific Functions and Data Members	2180	=head3 Watcher-Specific Functions and Data Members
2123		2181
2124	=over 4	2182	=over 4
2125		2183
2126	=item ev_idle_init (ev_signal *, callback)	2184	=item ev_idle_init (ev_idle *, callback)
2127		2185
2128	Initialises and configures the idle watcher - it has no parameters of any	2186	Initialises and configures the idle watcher - it has no parameters of any
2129	kind. There is a C<ev_idle_set> macro, but using it is utterly pointless,	2187	kind. There is a C<ev_idle_set> macro, but using it is utterly pointless,
2130	believe me.	2188	believe me.
2131		2189
…		…
2370	some fds have to be watched and handled very quickly (with low latency),	2428	some fds have to be watched and handled very quickly (with low latency),
2371	and even priorities and idle watchers might have too much overhead. In	2429	and even priorities and idle watchers might have too much overhead. In
2372	this case you would put all the high priority stuff in one loop and all	2430	this case you would put all the high priority stuff in one loop and all
2373	the rest in a second one, and embed the second one in the first.	2431	the rest in a second one, and embed the second one in the first.
2374		2432
2375	As long as the watcher is active, the callback will be invoked every time	2433	As long as the watcher is active, the callback will be invoked every
2376	there might be events pending in the embedded loop. The callback must then	2434	time there might be events pending in the embedded loop. The callback
2377	call C<ev_embed_sweep (mainloop, watcher)> to make a single sweep and invoke	2435	must then call C<ev_embed_sweep (mainloop, watcher)> to make a single
2378	their callbacks (you could also start an idle watcher to give the embedded	2436	sweep and invoke their callbacks (the callback doesn't need to invoke the
2379	loop strictly lower priority for example). You can also set the callback	2437	C<ev_embed_sweep> function directly, it could also start an idle watcher
2380	to C<0>, in which case the embed watcher will automatically execute the	2438	to give the embedded loop strictly lower priority for example).
2381	embedded loop sweep.
2382		2439
2383	As long as the watcher is started it will automatically handle events. The	2440	You can also set the callback to C<0>, in which case the embed watcher
2384	callback will be invoked whenever some events have been handled. You can	2441	will automatically execute the embedded loop sweep whenever necessary.
2385	set the callback to C<0> to avoid having to specify one if you are not
2386	interested in that.
2387		2442
2388	Also, there have not currently been made special provisions for forking:	2443	Fork detection will be handled transparently while the C<ev_embed> watcher
2389	when you fork, you not only have to call C<ev_loop_fork> on both loops,	2444	is active, i.e., the embedded loop will automatically be forked when the
2390	but you will also have to stop and restart any C<ev_embed> watchers	2445	embedding loop forks. In other cases, the user is responsible for calling
2391	yourself - but you can use a fork watcher to handle this automatically,	2446	C<ev_loop_fork> on the embedded loop.
2392	and future versions of libev might do just that.
2393		2447
2394	Unfortunately, not all backends are embeddable: only the ones returned by	2448	Unfortunately, not all backends are embeddable: only the ones returned by
2395	C<ev_embeddable_backends> are, which, unfortunately, does not include any	2449	C<ev_embeddable_backends> are, which, unfortunately, does not include any
2396	portable one.	2450	portable one.
2397		2451
…		…
2617	=over 4	2671	=over 4
2618		2672
2619	=item ev_async_init (ev_async *, callback)	2673	=item ev_async_init (ev_async *, callback)
2620		2674
2621	Initialises and configures the async watcher - it has no parameters of any	2675	Initialises and configures the async watcher - it has no parameters of any
2622	kind. There is a C<ev_asynd_set> macro, but using it is utterly pointless,	2676	kind. There is a C<ev_async_set> macro, but using it is utterly pointless,
2623	trust me.	2677	trust me.
2624		2678
2625	=item ev_async_send (loop, ev_async *)	2679	=item ev_async_send (loop, ev_async *)
2626		2680
2627	Sends/signals/activates the given C<ev_async> watcher, that is, feeds	2681	Sends/signals/activates the given C<ev_async> watcher, that is, feeds
…		…
2833		2887
2834	myclass obj;	2888	myclass obj;
2835	ev::io iow;	2889	ev::io iow;
2836	iow.set <myclass, &myclass::io_cb> (&obj);	2890	iow.set <myclass, &myclass::io_cb> (&obj);
2837		2891
		2892	=item w->set (object *)
		2893
		2894	This is an B<experimental> feature that might go away in a future version.
		2895
		2896	This is a variation of a method callback - leaving out the method to call
		2897	will default the method to C<operator ()>, which makes it possible to use
		2898	functor objects without having to manually specify the C<operator ()> all
		2899	the time. Incidentally, you can then also leave out the template argument
		2900	list.
		2901
		2902	The C<operator ()> method prototype must be C<void operator ()(watcher &w,
		2903	int revents)>.
		2904
		2905	See the method-C<set> above for more details.
		2906
		2907	Example: use a functor object as callback.
		2908
		2909	struct myfunctor
		2910	{
		2911	void operator() (ev::io &w, int revents)
		2912	{
		2913	...
		2914	}
		2915	}
		2916
		2917	myfunctor f;
		2918
		2919	ev::io w;
		2920	w.set (&f);
		2921
2838	=item w->set<function> (void *data = 0)	2922	=item w->set<function> (void *data = 0)
2839		2923
2840	Also sets a callback, but uses a static method or plain function as	2924	Also sets a callback, but uses a static method or plain function as
2841	callback. The optional C<data> argument will be stored in the watcher's	2925	callback. The optional C<data> argument will be stored in the watcher's
2842	C<data> member and is free for you to use.	2926	C<data> member and is free for you to use.
…		…
2941	Tony Arcieri has written a ruby extension that offers access to a subset	3025	Tony Arcieri has written a ruby extension that offers access to a subset
2942	of the libev API and adds file handle abstractions, asynchronous DNS and	3026	of the libev API and adds file handle abstractions, asynchronous DNS and
2943	more on top of it. It can be found via gem servers. Its homepage is at	3027	more on top of it. It can be found via gem servers. Its homepage is at
2944	L<http://rev.rubyforge.org/>.	3028	L<http://rev.rubyforge.org/>.
2945		3029
		3030	Roger Pack reports that using the link order C<-lws2_32 -lmsvcrt-ruby-190>
		3031	makes rev work even on mingw.
		3032
2946	=item D	3033	=item D
2947		3034
2948	Leandro Lucarella has written a D language binding (F<ev.d>) for libev, to	3035	Leandro Lucarella has written a D language binding (F<ev.d>) for libev, to
2949	be found at L<http://proj.llucax.com.ar/wiki/evd>.	3036	be found at L<http://proj.llucax.com.ar/wiki/evd>.
		3037
		3038	=item Ocaml
		3039
		3040	Erkki Seppala has written Ocaml bindings for libev, to be found at
		3041	L<http://modeemi.cs.tut.fi/~flux/software/ocaml-ev/>.
2950		3042
2951	=back	3043	=back
2952		3044
2953		3045
2954	=head1 MACRO MAGIC	3046	=head1 MACRO MAGIC
…		…
3055		3147
3056	#define EV_STANDALONE 1	3148	#define EV_STANDALONE 1
3057	#include "ev.h"	3149	#include "ev.h"
3058		3150
3059	Both header files and implementation files can be compiled with a C++	3151	Both header files and implementation files can be compiled with a C++
3060	compiler (at least, thats a stated goal, and breakage will be treated	3152	compiler (at least, that's a stated goal, and breakage will be treated
3061	as a bug).	3153	as a bug).
3062		3154
3063	You need the following files in your source tree, or in a directory	3155	You need the following files in your source tree, or in a directory
3064	in your include path (e.g. in libev/ when using -Ilibev):	3156	in your include path (e.g. in libev/ when using -Ilibev):
3065		3157
…		…
3121	keeps libev from including F<config.h>, and it also defines dummy	3213	keeps libev from including F<config.h>, and it also defines dummy
3122	implementations for some libevent functions (such as logging, which is not	3214	implementations for some libevent functions (such as logging, which is not
3123	supported). It will also not define any of the structs usually found in	3215	supported). It will also not define any of the structs usually found in
3124	F<event.h> that are not directly supported by the libev core alone.	3216	F<event.h> that are not directly supported by the libev core alone.
3125		3217
		3218	In stanbdalone mode, libev will still try to automatically deduce the
		3219	configuration, but has to be more conservative.
		3220
3126	=item EV_USE_MONOTONIC	3221	=item EV_USE_MONOTONIC
3127		3222
3128	If defined to be C<1>, libev will try to detect the availability of the	3223	If defined to be C<1>, libev will try to detect the availability of the
3129	monotonic clock option at both compile time and runtime. Otherwise no use	3224	monotonic clock option at both compile time and runtime. Otherwise no
3130	of the monotonic clock option will be attempted. If you enable this, you	3225	use of the monotonic clock option will be attempted. If you enable this,
3131	usually have to link against librt or something similar. Enabling it when	3226	you usually have to link against librt or something similar. Enabling it
3132	the functionality isn't available is safe, though, although you have	3227	when the functionality isn't available is safe, though, although you have
3133	to make sure you link against any libraries where the C<clock_gettime>	3228	to make sure you link against any libraries where the C<clock_gettime>
3134	function is hiding in (often F<-lrt>).	3229	function is hiding in (often F<-lrt>). See also C<EV_USE_CLOCK_SYSCALL>.
3135		3230
3136	=item EV_USE_REALTIME	3231	=item EV_USE_REALTIME
3137		3232
3138	If defined to be C<1>, libev will try to detect the availability of the	3233	If defined to be C<1>, libev will try to detect the availability of the
3139	real-time clock option at compile time (and assume its availability at	3234	real-time clock option at compile time (and assume its availability
3140	runtime if successful). Otherwise no use of the real-time clock option will	3235	at runtime if successful). Otherwise no use of the real-time clock
3141	be attempted. This effectively replaces C<gettimeofday> by C<clock_get	3236	option will be attempted. This effectively replaces C<gettimeofday>
3142	(CLOCK_REALTIME, ...)> and will not normally affect correctness. See the	3237	by C<clock_get (CLOCK_REALTIME, ...)> and will not normally affect
3143	note about libraries in the description of C<EV_USE_MONOTONIC>, though.	3238	correctness. See the note about libraries in the description of
		3239	C<EV_USE_MONOTONIC>, though. Defaults to the opposite value of
		3240	C<EV_USE_CLOCK_SYSCALL>.
		3241
		3242	=item EV_USE_CLOCK_SYSCALL
		3243
		3244	If defined to be C<1>, libev will try to use a direct syscall instead
		3245	of calling the system-provided C<clock_gettime> function. This option
		3246	exists because on GNU/Linux, C<clock_gettime> is in C<librt>, but C<librt>
		3247	unconditionally pulls in C<libpthread>, slowing down single-threaded
		3248	programs needlessly. Using a direct syscall is slightly slower (in
		3249	theory), because no optimised vdso implementation can be used, but avoids
		3250	the pthread dependency. Defaults to C<1> on GNU/Linux with glibc 2.x or
		3251	higher, as it simplifies linking (no need for C<-lrt>).
3144		3252
3145	=item EV_USE_NANOSLEEP	3253	=item EV_USE_NANOSLEEP
3146		3254
3147	If defined to be C<1>, libev will assume that C<nanosleep ()> is available	3255	If defined to be C<1>, libev will assume that C<nanosleep ()> is available
3148	and will use it for delays. Otherwise it will use C<select ()>.	3256	and will use it for delays. Otherwise it will use C<select ()>.
…		…
3164		3272
3165	=item EV_SELECT_USE_FD_SET	3273	=item EV_SELECT_USE_FD_SET
3166		3274
3167	If defined to C<1>, then the select backend will use the system C<fd_set>	3275	If defined to C<1>, then the select backend will use the system C<fd_set>
3168	structure. This is useful if libev doesn't compile due to a missing	3276	structure. This is useful if libev doesn't compile due to a missing
3169	C<NFDBITS> or C<fd_mask> definition or it mis-guesses the bitset layout on	3277	C<NFDBITS> or C<fd_mask> definition or it mis-guesses the bitset layout
3170	exotic systems. This usually limits the range of file descriptors to some	3278	on exotic systems. This usually limits the range of file descriptors to
3171	low limit such as 1024 or might have other limitations (winsocket only	3279	some low limit such as 1024 or might have other limitations (winsocket
3172	allows 64 sockets). The C<FD_SETSIZE> macro, set before compilation, might	3280	only allows 64 sockets). The C<FD_SETSIZE> macro, set before compilation,
3173	influence the size of the C<fd_set> used.	3281	configures the maximum size of the C<fd_set>.
3174		3282
3175	=item EV_SELECT_IS_WINSOCKET	3283	=item EV_SELECT_IS_WINSOCKET
3176		3284
3177	When defined to C<1>, the select backend will assume that	3285	When defined to C<1>, the select backend will assume that
3178	select/socket/connect etc. don't understand file descriptors but	3286	select/socket/connect etc. don't understand file descriptors but
…		…
3537	loop, as long as you don't confuse yourself). The only exception is that	3645	loop, as long as you don't confuse yourself). The only exception is that
3538	you must not do this from C<ev_periodic> reschedule callbacks.	3646	you must not do this from C<ev_periodic> reschedule callbacks.
3539		3647
3540	Care has been taken to ensure that libev does not keep local state inside	3648	Care has been taken to ensure that libev does not keep local state inside
3541	C<ev_loop>, and other calls do not usually allow for coroutine switches as	3649	C<ev_loop>, and other calls do not usually allow for coroutine switches as
3542	they do not clal any callbacks.	3650	they do not call any callbacks.
3543		3651
3544	=head2 COMPILER WARNINGS	3652	=head2 COMPILER WARNINGS
3545		3653
3546	Depending on your compiler and compiler settings, you might get no or a	3654	Depending on your compiler and compiler settings, you might get no or a
3547	lot of warnings when compiling libev code. Some people are apparently	3655	lot of warnings when compiling libev code. Some people are apparently
…		…
3581	==2274== definitely lost: 0 bytes in 0 blocks.	3689	==2274== definitely lost: 0 bytes in 0 blocks.
3582	==2274== possibly lost: 0 bytes in 0 blocks.	3690	==2274== possibly lost: 0 bytes in 0 blocks.
3583	==2274== still reachable: 256 bytes in 1 blocks.	3691	==2274== still reachable: 256 bytes in 1 blocks.
3584		3692
3585	Then there is no memory leak, just as memory accounted to global variables	3693	Then there is no memory leak, just as memory accounted to global variables
3586	is not a memleak - the memory is still being refernced, and didn't leak.	3694	is not a memleak - the memory is still being referenced, and didn't leak.
3587		3695
3588	Similarly, under some circumstances, valgrind might report kernel bugs	3696	Similarly, under some circumstances, valgrind might report kernel bugs
3589	as if it were a bug in libev (e.g. in realloc or in the poll backend,	3697	as if it were a bug in libev (e.g. in realloc or in the poll backend,
3590	although an acceptable workaround has been found here), or it might be	3698	although an acceptable workaround has been found here), or it might be
3591	confused.	3699	confused.
…		…
3829	=back	3937	=back
3830		3938
3831		3939
3832	=head1 AUTHOR	3940	=head1 AUTHOR
3833		3941
3834	Marc Lehmann <libev@schmorp.de>.	3942	Marc Lehmann <libev@schmorp.de>, with repeated corrections by Mikael Magnusson.
3835		3943

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Comparing libev/ev.pod (file contents): Revision 1.199 by root, Thu Oct 23 07:18:21 2008 UTC vs. Revision 1.226 by root, Wed Mar 4 12:51:37 2009 UTC

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Comparing libev/ev.pod (file contents):
Revision 1.199 by root, Thu Oct 23 07:18:21 2008 UTC vs.
Revision 1.226 by root, Wed Mar 4 12:51:37 2009 UTC