[ViewVC] Diff of: cvs/libev/ev.3

Comparing libev/ev.3 (file contents):
Revision 1.17 by root, Sat Nov 24 16:31:45 2007 UTC vs.
Revision 1.30 by root, Wed Nov 28 11:27:29 2007 UTC

…		…
127	.\}	127	.\}
128	.rm #[ #] #H #V #F C	128	.rm #[ #] #H #V #F C
129	.\" ========================================================================	129	.\" ========================================================================
130	.\"	130	.\"
131	.IX Title ""<STANDARD INPUT>" 1"	131	.IX Title ""<STANDARD INPUT>" 1"
132	.TH "<STANDARD INPUT>" 1 "2007-11-24" "perl v5.8.8" "User Contributed Perl Documentation"	132	.TH "<STANDARD INPUT>" 1 "2007-11-28" "perl v5.8.8" "User Contributed Perl Documentation"
133	.SH "NAME"	133	.SH "NAME"
134	libev \- a high performance full\-featured event loop written in C	134	libev \- a high performance full\-featured event loop written in C
135	.SH "SYNOPSIS"	135	.SH "SYNOPSIS"
136	.IX Header "SYNOPSIS"	136	.IX Header "SYNOPSIS"
137	.Vb 1	137	.Vb 1
138	\& #include <ev.h>	138	\& #include <ev.h>
139	.Ve	139	.Ve
		140	.SH "EXAMPLE PROGRAM"
		141	.IX Header "EXAMPLE PROGRAM"
		142	.Vb 1
		143	\& #include <ev.h>
		144	.Ve
		145	.PP
		146	.Vb 2
		147	\& ev_io stdin_watcher;
		148	\& ev_timer timeout_watcher;
		149	.Ve
		150	.PP
		151	.Vb 8
		152	\& /* called when data readable on stdin */
		153	\& static void
		154	\& stdin_cb (EV_P_ struct ev_io *w, int revents)
		155	\& {
		156	\& /* puts ("stdin ready"); */
		157	\& ev_io_stop (EV_A_ w); /* just a syntax example */
		158	\& ev_unloop (EV_A_ EVUNLOOP_ALL); /* leave all loop calls */
		159	\& }
		160	.Ve
		161	.PP
		162	.Vb 6
		163	\& static void
		164	\& timeout_cb (EV_P_ struct ev_timer *w, int revents)
		165	\& {
		166	\& /* puts ("timeout"); */
		167	\& ev_unloop (EV_A_ EVUNLOOP_ONE); /* leave one loop call */
		168	\& }
		169	.Ve
		170	.PP
		171	.Vb 4
		172	\& int
		173	\& main (void)
		174	\& {
		175	\& struct ev_loop *loop = ev_default_loop (0);
		176	.Ve
		177	.PP
		178	.Vb 3
		179	\& /* initialise an io watcher, then start it */
		180	\& ev_io_init (&stdin_watcher, stdin_cb, /STDIN_FILENO/ 0, EV_READ);
		181	\& ev_io_start (loop, &stdin_watcher);
		182	.Ve
		183	.PP
		184	.Vb 3
		185	\& /* simple non-repeating 5.5 second timeout */
		186	\& ev_timer_init (&timeout_watcher, timeout_cb, 5.5, 0.);
		187	\& ev_timer_start (loop, &timeout_watcher);
		188	.Ve
		189	.PP
		190	.Vb 2
		191	\& /* loop till timeout or data ready */
		192	\& ev_loop (loop, 0);
		193	.Ve
		194	.PP
		195	.Vb 2
		196	\& return 0;
		197	\& }
		198	.Ve
140	.SH "DESCRIPTION"	199	.SH "DESCRIPTION"
141	.IX Header "DESCRIPTION"	200	.IX Header "DESCRIPTION"
142	Libev is an event loop: you register interest in certain events (such as a	201	Libev is an event loop: you register interest in certain events (such as a
143	file descriptor being readable or a timeout occuring), and it will manage	202	file descriptor being readable or a timeout occuring), and it will manage
144	these event sources and provide your program with events.	203	these event sources and provide your program with events.
…		…
151	watchers\fR, which are relatively small C structures you initialise with the	210	watchers\fR, which are relatively small C structures you initialise with the
152	details of the event, and then hand it over to libev by \fIstarting\fR the	211	details of the event, and then hand it over to libev by \fIstarting\fR the
153	watcher.	212	watcher.
154	.SH "FEATURES"	213	.SH "FEATURES"
155	.IX Header "FEATURES"	214	.IX Header "FEATURES"
156	Libev supports select, poll, the linux-specific epoll and the bsd-specific	215	Libev supports \f(CW\(C`select\(C'\fR, \f(CW\(C`poll\(C'\fR, the linux-specific \f(CW\(C`epoll\(C'\fR, the
157	kqueue mechanisms for file descriptor events, relative timers, absolute	216	bsd-specific \f(CW\(C`kqueue\(C'\fR and the solaris-specific event port mechanisms
158	timers with customised rescheduling, signal events, process status change	217	for file descriptor events (\f(CW\(C`ev_io\(C'\fR), relative timers (\f(CW\(C`ev_timer\(C'\fR),
159	events (related to \s-1SIGCHLD\s0), and event watchers dealing with the event	218	absolute timers with customised rescheduling (\f(CW\(C`ev_periodic\(C'\fR), synchronous
160	loop mechanism itself (idle, prepare and check watchers). It also is quite	219	signals (\f(CW\(C`ev_signal\(C'\fR), process status change events (\f(CW\(C`ev_child\(C'\fR), and
161	fast (see this benchmark comparing	220	event watchers dealing with the event loop mechanism itself (\f(CW\(C`ev_idle\(C'\fR,
162	it to libevent for example).	221	\&\f(CW\(C`ev_embed\(C'\fR, \f(CW\(C`ev_prepare\(C'\fR and \f(CW\(C`ev_check\(C'\fR watchers) as well as
		222	file watchers (\f(CW\(C`ev_stat\(C'\fR) and even limited support for fork events
		223	(\f(CW\(C`ev_fork\(C'\fR).
		224	.PP
		225	It also is quite fast (see this
		226	benchmark comparing it to libevent
		227	for example).
163	.SH "CONVENTIONS"	228	.SH "CONVENTIONS"
164	.IX Header "CONVENTIONS"	229	.IX Header "CONVENTIONS"
165	Libev is very configurable. In this manual the default configuration	230	Libev is very configurable. In this manual the default configuration will
166	will be described, which supports multiple event loops. For more info	231	be described, which supports multiple event loops. For more info about
167	about various configuration options please have a look at the file	232	various configuration options please have a look at \fB\s-1EMBED\s0\fR section in
168	\&\fI\s-1README\s0.embed\fR in the libev distribution. If libev was configured without	233	this manual. If libev was configured without support for multiple event
169	support for multiple event loops, then all functions taking an initial	234	loops, then all functions taking an initial argument of name \f(CW\(C`loop\(C'\fR
170	argument of name \f(CW\(C`loop\(C'\fR (which is always of type \f(CW\(C`struct ev_loop \*(C'\fR)	235	(which is always of type \f(CW\(C`struct ev_loop \*(C'\fR) will not have this argument.
171	will not have this argument.
172	.SH "TIME REPRESENTATION"	236	.SH "TIME REPRESENTATION"
173	.IX Header "TIME REPRESENTATION"	237	.IX Header "TIME REPRESENTATION"
174	Libev represents time as a single floating point number, representing the	238	Libev represents time as a single floating point number, representing the
175	(fractional) number of seconds since the (\s-1POSIX\s0) epoch (somewhere near	239	(fractional) number of seconds since the (\s-1POSIX\s0) epoch (somewhere near
176	the beginning of 1970, details are complicated, don't ask). This type is	240	the beginning of 1970, details are complicated, don't ask). This type is
…		…
201	Usually, it's a good idea to terminate if the major versions mismatch,	265	Usually, it's a good idea to terminate if the major versions mismatch,
202	as this indicates an incompatible change. Minor versions are usually	266	as this indicates an incompatible change. Minor versions are usually
203	compatible to older versions, so a larger minor version alone is usually	267	compatible to older versions, so a larger minor version alone is usually
204	not a problem.	268	not a problem.
205	.Sp	269	.Sp
206	Example: make sure we haven't accidentally been linked against the wrong	270	Example: Make sure we haven't accidentally been linked against the wrong
207	version:	271	version.
208	.Sp	272	.Sp
209	.Vb 3	273	.Vb 3
210	\& assert (("libev version mismatch",	274	\& assert (("libev version mismatch",
211	\& ev_version_major () == EV_VERSION_MAJOR	275	\& ev_version_major () == EV_VERSION_MAJOR
212	\& && ev_version_minor () >= EV_VERSION_MINOR));	276	\& && ev_version_minor () >= EV_VERSION_MINOR));
…		…
240	might be supported on the current system, you would need to look at	304	might be supported on the current system, you would need to look at
241	\&\f(CW\(C`ev_embeddable_backends () & ev_supported_backends ()\(C'\fR, likewise for	305	\&\f(CW\(C`ev_embeddable_backends () & ev_supported_backends ()\(C'\fR, likewise for
242	recommended ones.	306	recommended ones.
243	.Sp	307	.Sp
244	See the description of \f(CW\(C`ev_embed\(C'\fR watchers for more info.	308	See the description of \f(CW\(C`ev_embed\(C'\fR watchers for more info.
245	.IP "ev_set_allocator (void (cb)(void *ptr, long size))" 4	309	.IP "ev_set_allocator (void (cb)(void *ptr, size_t size))" 4
246	.IX Item "ev_set_allocator (void (cb)(void *ptr, long size))"	310	.IX Item "ev_set_allocator (void (cb)(void *ptr, size_t size))"
247	Sets the allocation function to use (the prototype is similar to the	311	Sets the allocation function to use (the prototype and semantics are
248	realloc C function, the semantics are identical). It is used to allocate	312	identical to the realloc C function). It is used to allocate and free
249	and free memory (no surprises here). If it returns zero when memory	313	memory (no surprises here). If it returns zero when memory needs to be
250	needs to be allocated, the library might abort or take some potentially	314	allocated, the library might abort or take some potentially destructive
251	destructive action. The default is your system realloc function.	315	action. The default is your system realloc function.
252	.Sp	316	.Sp
253	You could override this function in high-availability programs to, say,	317	You could override this function in high-availability programs to, say,
254	free some memory if it cannot allocate memory, to use a special allocator,	318	free some memory if it cannot allocate memory, to use a special allocator,
255	or even to sleep a while and retry until some memory is available.	319	or even to sleep a while and retry until some memory is available.
256	.Sp	320	.Sp
257	Example: replace the libev allocator with one that waits a bit and then	321	Example: Replace the libev allocator with one that waits a bit and then
258	retries: better than mine).	322	retries).
259	.Sp	323	.Sp
260	.Vb 6	324	.Vb 6
261	\& static void *	325	\& static void *
262	\& persistent_realloc (void *ptr, long size)	326	\& persistent_realloc (void *ptr, size_t size)
263	\& {	327	\& {
264	\& for (;;)	328	\& for (;;)
265	\& {	329	\& {
266	\& void *newptr = realloc (ptr, size);	330	\& void *newptr = realloc (ptr, size);
267	.Ve	331	.Ve
…		…
289	callback is set, then libev will expect it to remedy the sitution, no	353	callback is set, then libev will expect it to remedy the sitution, no
290	matter what, when it returns. That is, libev will generally retry the	354	matter what, when it returns. That is, libev will generally retry the
291	requested operation, or, if the condition doesn't go away, do bad stuff	355	requested operation, or, if the condition doesn't go away, do bad stuff
292	(such as abort).	356	(such as abort).
293	.Sp	357	.Sp
294	Example: do the same thing as libev does internally:	358	Example: This is basically the same thing that libev does internally, too.
295	.Sp	359	.Sp
296	.Vb 6	360	.Vb 6
297	\& static void	361	\& static void
298	\& fatal_error (const char *msg)	362	\& fatal_error (const char *msg)
299	\& {	363	\& {
…		…
448	Similar to \f(CW\(C`ev_default_loop\(C'\fR, but always creates a new event loop that is	512	Similar to \f(CW\(C`ev_default_loop\(C'\fR, but always creates a new event loop that is
449	always distinct from the default loop. Unlike the default loop, it cannot	513	always distinct from the default loop. Unlike the default loop, it cannot
450	handle signal and child watchers, and attempts to do so will be greeted by	514	handle signal and child watchers, and attempts to do so will be greeted by
451	undefined behaviour (or a failed assertion if assertions are enabled).	515	undefined behaviour (or a failed assertion if assertions are enabled).
452	.Sp	516	.Sp
453	Example: try to create a event loop that uses epoll and nothing else.	517	Example: Try to create a event loop that uses epoll and nothing else.
454	.Sp	518	.Sp
455	.Vb 3	519	.Vb 3
456	\& struct ev_loop *epoller = ev_loop_new (EVBACKEND_EPOLL \| EVFLAG_NOENV);	520	\& struct ev_loop *epoller = ev_loop_new (EVBACKEND_EPOLL \| EVFLAG_NOENV);
457	\& if (!epoller)	521	\& if (!epoller)
458	\& fatal ("no epoll found here, maybe it hides under your chair");	522	\& fatal ("no epoll found here, maybe it hides under your chair");
…		…
556	\& be handled here by queueing them when their watcher gets executed.	620	\& be handled here by queueing them when their watcher gets executed.
557	\& - If ev_unloop has been called or EVLOOP_ONESHOT or EVLOOP_NONBLOCK	621	\& - If ev_unloop has been called or EVLOOP_ONESHOT or EVLOOP_NONBLOCK
558	\& were used, return, otherwise continue with step *.	622	\& were used, return, otherwise continue with step *.
559	.Ve	623	.Ve
560	.Sp	624	.Sp
561	Example: queue some jobs and then loop until no events are outsanding	625	Example: Queue some jobs and then loop until no events are outsanding
562	anymore.	626	anymore.
563	.Sp	627	.Sp
564	.Vb 4	628	.Vb 4
565	\& ... queue jobs here, make sure they register event watchers as long	629	\& ... queue jobs here, make sure they register event watchers as long
566	\& ... as they still have work to do (even an idle watcher will do..)	630	\& ... as they still have work to do (even an idle watcher will do..)
…		…
588	visible to the libev user and should not keep \f(CW\(C`ev_loop\(C'\fR from exiting if	652	visible to the libev user and should not keep \f(CW\(C`ev_loop\(C'\fR from exiting if
589	no event watchers registered by it are active. It is also an excellent	653	no event watchers registered by it are active. It is also an excellent
590	way to do this for generic recurring timers or from within third-party	654	way to do this for generic recurring timers or from within third-party
591	libraries. Just remember to \fIunref after start\fR and \fIref before stop\fR.	655	libraries. Just remember to \fIunref after start\fR and \fIref before stop\fR.
592	.Sp	656	.Sp
593	Example: create a signal watcher, but keep it from keeping \f(CW\(C`ev_loop\(C'\fR	657	Example: Create a signal watcher, but keep it from keeping \f(CW\(C`ev_loop\(C'\fR
594	running when nothing else is active.	658	running when nothing else is active.
595	.Sp	659	.Sp
596	.Vb 4	660	.Vb 4
597	\& struct dv_signal exitsig;	661	\& struct ev_signal exitsig;
598	\& ev_signal_init (&exitsig, sig_cb, SIGINT);	662	\& ev_signal_init (&exitsig, sig_cb, SIGINT);
599	\& ev_signal_start (myloop, &exitsig);	663	\& ev_signal_start (loop, &exitsig);
600	\& evf_unref (myloop);	664	\& evf_unref (loop);
601	.Ve	665	.Ve
602	.Sp	666	.Sp
603	Example: for some weird reason, unregister the above signal handler again.	667	Example: For some weird reason, unregister the above signal handler again.
604	.Sp	668	.Sp
605	.Vb 2	669	.Vb 2
606	\& ev_ref (myloop);	670	\& ev_ref (loop);
607	\& ev_signal_stop (myloop, &exitsig);	671	\& ev_signal_stop (loop, &exitsig);
608	.Ve	672	.Ve
609	.SH "ANATOMY OF A WATCHER"	673	.SH "ANATOMY OF A WATCHER"
610	.IX Header "ANATOMY OF A WATCHER"	674	.IX Header "ANATOMY OF A WATCHER"
611	A watcher is a structure that you create and register to record your	675	A watcher is a structure that you create and register to record your
612	interest in some event. For instance, if you want to wait for \s-1STDIN\s0 to	676	interest in some event. For instance, if you want to wait for \s-1STDIN\s0 to
…		…
684	The signal specified in the \f(CW\(C`ev_signal\(C'\fR watcher has been received by a thread.	748	The signal specified in the \f(CW\(C`ev_signal\(C'\fR watcher has been received by a thread.
685	.ie n .IP """EV_CHILD""" 4	749	.ie n .IP """EV_CHILD""" 4
686	.el .IP "\f(CWEV_CHILD\fR" 4	750	.el .IP "\f(CWEV_CHILD\fR" 4
687	.IX Item "EV_CHILD"	751	.IX Item "EV_CHILD"
688	The pid specified in the \f(CW\(C`ev_child\(C'\fR watcher has received a status change.	752	The pid specified in the \f(CW\(C`ev_child\(C'\fR watcher has received a status change.
		753	.ie n .IP """EV_STAT""" 4
		754	.el .IP "\f(CWEV_STAT\fR" 4
		755	.IX Item "EV_STAT"
		756	The path specified in the \f(CW\(C`ev_stat\(C'\fR watcher changed its attributes somehow.
689	.ie n .IP """EV_IDLE""" 4	757	.ie n .IP """EV_IDLE""" 4
690	.el .IP "\f(CWEV_IDLE\fR" 4	758	.el .IP "\f(CWEV_IDLE\fR" 4
691	.IX Item "EV_IDLE"	759	.IX Item "EV_IDLE"
692	The \f(CW\(C`ev_idle\(C'\fR watcher has determined that you have nothing better to do.	760	The \f(CW\(C`ev_idle\(C'\fR watcher has determined that you have nothing better to do.
693	.ie n .IP """EV_PREPARE""" 4	761	.ie n .IP """EV_PREPARE""" 4
…		…
703	\&\f(CW\(C`ev_loop\(C'\fR has gathered them, but before it invokes any callbacks for any	771	\&\f(CW\(C`ev_loop\(C'\fR has gathered them, but before it invokes any callbacks for any
704	received events. Callbacks of both watcher types can start and stop as	772	received events. Callbacks of both watcher types can start and stop as
705	many watchers as they want, and all of them will be taken into account	773	many watchers as they want, and all of them will be taken into account
706	(for example, a \f(CW\(C`ev_prepare\(C'\fR watcher might start an idle watcher to keep	774	(for example, a \f(CW\(C`ev_prepare\(C'\fR watcher might start an idle watcher to keep
707	\&\f(CW\(C`ev_loop\(C'\fR from blocking).	775	\&\f(CW\(C`ev_loop\(C'\fR from blocking).
		776	.ie n .IP """EV_EMBED""" 4
		777	.el .IP "\f(CWEV_EMBED\fR" 4
		778	.IX Item "EV_EMBED"
		779	The embedded event loop specified in the \f(CW\(C`ev_embed\(C'\fR watcher needs attention.
		780	.ie n .IP """EV_FORK""" 4
		781	.el .IP "\f(CWEV_FORK\fR" 4
		782	.IX Item "EV_FORK"
		783	The event loop has been resumed in the child process after fork (see
		784	\&\f(CW\(C`ev_fork\(C'\fR).
708	.ie n .IP """EV_ERROR""" 4	785	.ie n .IP """EV_ERROR""" 4
709	.el .IP "\f(CWEV_ERROR\fR" 4	786	.el .IP "\f(CWEV_ERROR\fR" 4
710	.IX Item "EV_ERROR"	787	.IX Item "EV_ERROR"
711	An unspecified error has occured, the watcher has been stopped. This might	788	An unspecified error has occured, the watcher has been stopped. This might
712	happen because the watcher could not be properly started because libev	789	happen because the watcher could not be properly started because libev
…		…
779	Returns a true value iff the watcher is pending, (i.e. it has outstanding	856	Returns a true value iff the watcher is pending, (i.e. it has outstanding
780	events but its callback has not yet been invoked). As long as a watcher	857	events but its callback has not yet been invoked). As long as a watcher
781	is pending (but not active) you must not call an init function on it (but	858	is pending (but not active) you must not call an init function on it (but
782	\&\f(CW\(C`ev_TYPE_set\(C'\fR is safe) and you must make sure the watcher is available to	859	\&\f(CW\(C`ev_TYPE_set\(C'\fR is safe) and you must make sure the watcher is available to
783	libev (e.g. you cnanot \f(CW\(C`free ()\(C'\fR it).	860	libev (e.g. you cnanot \f(CW\(C`free ()\(C'\fR it).
784	.IP "callback = ev_cb (ev_TYPE *watcher)" 4	861	.IP "callback ev_cb (ev_TYPE *watcher)" 4
785	.IX Item "callback = ev_cb (ev_TYPE *watcher)"	862	.IX Item "callback ev_cb (ev_TYPE *watcher)"
786	Returns the callback currently set on the watcher.	863	Returns the callback currently set on the watcher.
787	.IP "ev_cb_set (ev_TYPE *watcher, callback)" 4	864	.IP "ev_cb_set (ev_TYPE *watcher, callback)" 4
788	.IX Item "ev_cb_set (ev_TYPE *watcher, callback)"	865	.IX Item "ev_cb_set (ev_TYPE *watcher, callback)"
789	Change the callback. You can change the callback at virtually any time	866	Change the callback. You can change the callback at virtually any time
790	(modulo threads).	867	(modulo threads).
…		…
816	\& struct my_io w = (struct my_io )w_;	893	\& struct my_io w = (struct my_io )w_;
817	\& ...	894	\& ...
818	\& }	895	\& }
819	.Ve	896	.Ve
820	.PP	897	.PP
821	More interesting and less C\-conformant ways of catsing your callback type	898	More interesting and less C\-conformant ways of casting your callback type
822	have been omitted....	899	instead have been omitted.
		900	.PP
		901	Another common scenario is having some data structure with multiple
		902	watchers:
		903	.PP
		904	.Vb 6
		905	\& struct my_biggy
		906	\& {
		907	\& int some_data;
		908	\& ev_timer t1;
		909	\& ev_timer t2;
		910	\& }
		911	.Ve
		912	.PP
		913	In this case getting the pointer to \f(CW\(C`my_biggy\(C'\fR is a bit more complicated,
		914	you need to use \f(CW\(C`offsetof\(C'\fR:
		915	.PP
		916	.Vb 1
		917	\& #include <stddef.h>
		918	.Ve
		919	.PP
		920	.Vb 6
		921	\& static void
		922	\& t1_cb (EV_P_ struct ev_timer *w, int revents)
		923	\& {
		924	\& struct my_biggy big = (struct my_biggy *
		925	\& (((char *)w) - offsetof (struct my_biggy, t1));
		926	\& }
		927	.Ve
		928	.PP
		929	.Vb 6
		930	\& static void
		931	\& t2_cb (EV_P_ struct ev_timer *w, int revents)
		932	\& {
		933	\& struct my_biggy big = (struct my_biggy *
		934	\& (((char *)w) - offsetof (struct my_biggy, t2));
		935	\& }
		936	.Ve
823	.SH "WATCHER TYPES"	937	.SH "WATCHER TYPES"
824	.IX Header "WATCHER TYPES"	938	.IX Header "WATCHER TYPES"
825	This section describes each watcher in detail, but will not repeat	939	This section describes each watcher in detail, but will not repeat
826	information given in the last section.	940	information given in the last section. Any initialisation/set macros,
		941	functions and members specific to the watcher type are explained.
		942	.PP
		943	Members are additionally marked with either \fI[read\-only]\fR, meaning that,
		944	while the watcher is active, you can look at the member and expect some
		945	sensible content, but you must not modify it (you can modify it while the
		946	watcher is stopped to your hearts content), or \fI[read\-write]\fR, which
		947	means you can expect it to have some sensible content while the watcher
		948	is active, but you can also modify it. Modifying it may not do something
		949	sensible or take immediate effect (or do anything at all), but libev will
		950	not crash or malfunction in any way.
827	.ie n .Sh """ev_io"" \- is this file descriptor readable or writable?"	951	.ie n .Sh """ev_io"" \- is this file descriptor readable or writable?"
828	.el .Sh "\f(CWev_io\fP \- is this file descriptor readable or writable?"	952	.el .Sh "\f(CWev_io\fP \- is this file descriptor readable or writable?"
829	.IX Subsection "ev_io - is this file descriptor readable or writable?"	953	.IX Subsection "ev_io - is this file descriptor readable or writable?"
830	I/O watchers check whether a file descriptor is readable or writable	954	I/O watchers check whether a file descriptor is readable or writable
831	in each iteration of the event loop, or, more precisely, when reading	955	in each iteration of the event loop, or, more precisely, when reading
…		…
871	.IX Item "ev_io_set (ev_io *, int fd, int events)"	995	.IX Item "ev_io_set (ev_io *, int fd, int events)"
872	.PD	996	.PD
873	Configures an \f(CW\(C`ev_io\(C'\fR watcher. The \f(CW\(C`fd\(C'\fR is the file descriptor to	997	Configures an \f(CW\(C`ev_io\(C'\fR watcher. The \f(CW\(C`fd\(C'\fR is the file descriptor to
874	rceeive events for and events is either \f(CW\(C`EV_READ\(C'\fR, \f(CW\(C`EV_WRITE\(C'\fR or	998	rceeive events for and events is either \f(CW\(C`EV_READ\(C'\fR, \f(CW\(C`EV_WRITE\(C'\fR or
875	\&\f(CW\(C`EV_READ \| EV_WRITE\(C'\fR to receive the given events.	999	\&\f(CW\(C`EV_READ \| EV_WRITE\(C'\fR to receive the given events.
		1000	.IP "int fd [read\-only]" 4
		1001	.IX Item "int fd [read-only]"
		1002	The file descriptor being watched.
		1003	.IP "int events [read\-only]" 4
		1004	.IX Item "int events [read-only]"
		1005	The events being watched.
876	.PP	1006	.PP
877	Example: call \f(CW\(C`stdin_readable_cb\(C'\fR when \s-1STDIN_FILENO\s0 has become, well	1007	Example: Call \f(CW\(C`stdin_readable_cb\(C'\fR when \s-1STDIN_FILENO\s0 has become, well
878	readable, but only once. Since it is likely line\-buffered, you could	1008	readable, but only once. Since it is likely line\-buffered, you could
879	attempt to read a whole line in the callback:	1009	attempt to read a whole line in the callback.
880	.PP	1010	.PP
881	.Vb 6	1011	.Vb 6
882	\& static void	1012	\& static void
883	\& stdin_readable_cb (struct ev_loop loop, struct ev_io w, int revents)	1013	\& stdin_readable_cb (struct ev_loop loop, struct ev_io w, int revents)
884	\& {	1014	\& {
…		…
945	.Sp	1075	.Sp
946	If the timer is repeating, either start it if necessary (with the repeat	1076	If the timer is repeating, either start it if necessary (with the repeat
947	value), or reset the running timer to the repeat value.	1077	value), or reset the running timer to the repeat value.
948	.Sp	1078	.Sp
949	This sounds a bit complicated, but here is a useful and typical	1079	This sounds a bit complicated, but here is a useful and typical
950	example: Imagine you have a tcp connection and you want a so-called idle	1080	example: Imagine you have a tcp connection and you want a so-called
951	timeout, that is, you want to be called when there have been, say, 60	1081	idle timeout, that is, you want to be called when there have been,
952	seconds of inactivity on the socket. The easiest way to do this is to	1082	say, 60 seconds of inactivity on the socket. The easiest way to do
953	configure an \f(CW\(C`ev_timer\(C'\fR with after=repeat=60 and calling ev_timer_again each	1083	this is to configure an \f(CW\(C`ev_timer\(C'\fR with \f(CW\(C`after\(C'\fR=\f(CW\(C`repeat\(C'\fR=\f(CW60\fR and calling
954	time you successfully read or write some data. If you go into an idle	1084	\&\f(CW\(C`ev_timer_again\(C'\fR each time you successfully read or write some data. If
955	state where you do not expect data to travel on the socket, you can stop	1085	you go into an idle state where you do not expect data to travel on the
956	the timer, and again will automatically restart it if need be.	1086	socket, you can stop the timer, and again will automatically restart it if
		1087	need be.
		1088	.Sp
		1089	You can also ignore the \f(CW\(C`after\(C'\fR value and \f(CW\(C`ev_timer_start\(C'\fR altogether
		1090	and only ever use the \f(CW\(C`repeat\(C'\fR value:
		1091	.Sp
		1092	.Vb 8
		1093	\& ev_timer_init (timer, callback, 0., 5.);
		1094	\& ev_timer_again (loop, timer);
		1095	\& ...
		1096	\& timer->again = 17.;
		1097	\& ev_timer_again (loop, timer);
		1098	\& ...
		1099	\& timer->again = 10.;
		1100	\& ev_timer_again (loop, timer);
		1101	.Ve
		1102	.Sp
		1103	This is more efficient then stopping/starting the timer eahc time you want
		1104	to modify its timeout value.
		1105	.IP "ev_tstamp repeat [read\-write]" 4
		1106	.IX Item "ev_tstamp repeat [read-write]"
		1107	The current \f(CW\(C`repeat\(C'\fR value. Will be used each time the watcher times out
		1108	or \f(CW\(C`ev_timer_again\(C'\fR is called and determines the next timeout (if any),
		1109	which is also when any modifications are taken into account.
957	.PP	1110	.PP
958	Example: create a timer that fires after 60 seconds.	1111	Example: Create a timer that fires after 60 seconds.
959	.PP	1112	.PP
960	.Vb 5	1113	.Vb 5
961	\& static void	1114	\& static void
962	\& one_minute_cb (struct ev_loop loop, struct ev_timer w, int revents)	1115	\& one_minute_cb (struct ev_loop loop, struct ev_timer w, int revents)
963	\& {	1116	\& {
…		…
969	\& struct ev_timer mytimer;	1122	\& struct ev_timer mytimer;
970	\& ev_timer_init (&mytimer, one_minute_cb, 60., 0.);	1123	\& ev_timer_init (&mytimer, one_minute_cb, 60., 0.);
971	\& ev_timer_start (loop, &mytimer);	1124	\& ev_timer_start (loop, &mytimer);
972	.Ve	1125	.Ve
973	.PP	1126	.PP
974	Example: create a timeout timer that times out after 10 seconds of	1127	Example: Create a timeout timer that times out after 10 seconds of
975	inactivity.	1128	inactivity.
976	.PP	1129	.PP
977	.Vb 5	1130	.Vb 5
978	\& static void	1131	\& static void
979	\& timeout_cb (struct ev_loop loop, struct ev_timer w, int revents)	1132	\& timeout_cb (struct ev_loop loop, struct ev_timer w, int revents)
…		…
1093	.IX Item "ev_periodic_again (loop, ev_periodic *)"	1246	.IX Item "ev_periodic_again (loop, ev_periodic *)"
1094	Simply stops and restarts the periodic watcher again. This is only useful	1247	Simply stops and restarts the periodic watcher again. This is only useful
1095	when you changed some parameters or the reschedule callback would return	1248	when you changed some parameters or the reschedule callback would return
1096	a different time than the last time it was called (e.g. in a crond like	1249	a different time than the last time it was called (e.g. in a crond like
1097	program when the crontabs have changed).	1250	program when the crontabs have changed).
		1251	.IP "ev_tstamp interval [read\-write]" 4
		1252	.IX Item "ev_tstamp interval [read-write]"
		1253	The current interval value. Can be modified any time, but changes only
		1254	take effect when the periodic timer fires or \f(CW\(C`ev_periodic_again\(C'\fR is being
		1255	called.
		1256	.IP "ev_tstamp (reschedule_cb)(struct ev_periodic w, ev_tstamp now) [read\-write]" 4
		1257	.IX Item "ev_tstamp (reschedule_cb)(struct ev_periodic w, ev_tstamp now) [read-write]"
		1258	The current reschedule callback, or \f(CW0\fR, if this functionality is
		1259	switched off. Can be changed any time, but changes only take effect when
		1260	the periodic timer fires or \f(CW\(C`ev_periodic_again\(C'\fR is being called.
1098	.PP	1261	.PP
1099	Example: call a callback every hour, or, more precisely, whenever the	1262	Example: Call a callback every hour, or, more precisely, whenever the
1100	system clock is divisible by 3600. The callback invocation times have	1263	system clock is divisible by 3600. The callback invocation times have
1101	potentially a lot of jittering, but good long-term stability.	1264	potentially a lot of jittering, but good long-term stability.
1102	.PP	1265	.PP
1103	.Vb 5	1266	.Vb 5
1104	\& static void	1267	\& static void
…		…
1112	\& struct ev_periodic hourly_tick;	1275	\& struct ev_periodic hourly_tick;
1113	\& ev_periodic_init (&hourly_tick, clock_cb, 0., 3600., 0);	1276	\& ev_periodic_init (&hourly_tick, clock_cb, 0., 3600., 0);
1114	\& ev_periodic_start (loop, &hourly_tick);	1277	\& ev_periodic_start (loop, &hourly_tick);
1115	.Ve	1278	.Ve
1116	.PP	1279	.PP
1117	Example: the same as above, but use a reschedule callback to do it:	1280	Example: The same as above, but use a reschedule callback to do it:
1118	.PP	1281	.PP
1119	.Vb 1	1282	.Vb 1
1120	\& #include <math.h>	1283	\& #include <math.h>
1121	.Ve	1284	.Ve
1122	.PP	1285	.PP
…		…
1130	.PP	1293	.PP
1131	.Vb 1	1294	.Vb 1
1132	\& ev_periodic_init (&hourly_tick, clock_cb, 0., 0., my_scheduler_cb);	1295	\& ev_periodic_init (&hourly_tick, clock_cb, 0., 0., my_scheduler_cb);
1133	.Ve	1296	.Ve
1134	.PP	1297	.PP
1135	Example: call a callback every hour, starting now:	1298	Example: Call a callback every hour, starting now:
1136	.PP	1299	.PP
1137	.Vb 4	1300	.Vb 4
1138	\& struct ev_periodic hourly_tick;	1301	\& struct ev_periodic hourly_tick;
1139	\& ev_periodic_init (&hourly_tick, clock_cb,	1302	\& ev_periodic_init (&hourly_tick, clock_cb,
1140	\& fmod (ev_now (loop), 3600.), 3600., 0);	1303	\& fmod (ev_now (loop), 3600.), 3600., 0);
…		…
1160	.IP "ev_signal_set (ev_signal *, int signum)" 4	1323	.IP "ev_signal_set (ev_signal *, int signum)" 4
1161	.IX Item "ev_signal_set (ev_signal *, int signum)"	1324	.IX Item "ev_signal_set (ev_signal *, int signum)"
1162	.PD	1325	.PD
1163	Configures the watcher to trigger on the given signal number (usually one	1326	Configures the watcher to trigger on the given signal number (usually one
1164	of the \f(CW\(C`SIGxxx\(C'\fR constants).	1327	of the \f(CW\(C`SIGxxx\(C'\fR constants).
		1328	.IP "int signum [read\-only]" 4
		1329	.IX Item "int signum [read-only]"
		1330	The signal the watcher watches out for.
1165	.ie n .Sh """ev_child"" \- watch out for process status changes"	1331	.ie n .Sh """ev_child"" \- watch out for process status changes"
1166	.el .Sh "\f(CWev_child\fP \- watch out for process status changes"	1332	.el .Sh "\f(CWev_child\fP \- watch out for process status changes"
1167	.IX Subsection "ev_child - watch out for process status changes"	1333	.IX Subsection "ev_child - watch out for process status changes"
1168	Child watchers trigger when your process receives a \s-1SIGCHLD\s0 in response to	1334	Child watchers trigger when your process receives a \s-1SIGCHLD\s0 in response to
1169	some child status changes (most typically when a child of yours dies).	1335	some child status changes (most typically when a child of yours dies).
…		…
1177	\&\fIany\fR process if \f(CW\(C`pid\(C'\fR is specified as \f(CW0\fR). The callback can look	1343	\&\fIany\fR process if \f(CW\(C`pid\(C'\fR is specified as \f(CW0\fR). The callback can look
1178	at the \f(CW\(C`rstatus\(C'\fR member of the \f(CW\(C`ev_child\(C'\fR watcher structure to see	1344	at the \f(CW\(C`rstatus\(C'\fR member of the \f(CW\(C`ev_child\(C'\fR watcher structure to see
1179	the status word (use the macros from \f(CW\(C`sys/wait.h\(C'\fR and see your systems	1345	the status word (use the macros from \f(CW\(C`sys/wait.h\(C'\fR and see your systems
1180	\&\f(CW\(C`waitpid\(C'\fR documentation). The \f(CW\(C`rpid\(C'\fR member contains the pid of the	1346	\&\f(CW\(C`waitpid\(C'\fR documentation). The \f(CW\(C`rpid\(C'\fR member contains the pid of the
1181	process causing the status change.	1347	process causing the status change.
		1348	.IP "int pid [read\-only]" 4
		1349	.IX Item "int pid [read-only]"
		1350	The process id this watcher watches out for, or \f(CW0\fR, meaning any process id.
		1351	.IP "int rpid [read\-write]" 4
		1352	.IX Item "int rpid [read-write]"
		1353	The process id that detected a status change.
		1354	.IP "int rstatus [read\-write]" 4
		1355	.IX Item "int rstatus [read-write]"
		1356	The process exit/trace status caused by \f(CW\(C`rpid\(C'\fR (see your systems
		1357	\&\f(CW\(C`waitpid\(C'\fR and \f(CW\(C`sys/wait.h\(C'\fR documentation for details).
1182	.PP	1358	.PP
1183	Example: try to exit cleanly on \s-1SIGINT\s0 and \s-1SIGTERM\s0.	1359	Example: Try to exit cleanly on \s-1SIGINT\s0 and \s-1SIGTERM\s0.
1184	.PP	1360	.PP
1185	.Vb 5	1361	.Vb 5
1186	\& static void	1362	\& static void
1187	\& sigint_cb (struct ev_loop loop, struct ev_signal w, int revents)	1363	\& sigint_cb (struct ev_loop loop, struct ev_signal w, int revents)
1188	\& {	1364	\& {
…		…
1192	.PP	1368	.PP
1193	.Vb 3	1369	.Vb 3
1194	\& struct ev_signal signal_watcher;	1370	\& struct ev_signal signal_watcher;
1195	\& ev_signal_init (&signal_watcher, sigint_cb, SIGINT);	1371	\& ev_signal_init (&signal_watcher, sigint_cb, SIGINT);
1196	\& ev_signal_start (loop, &sigint_cb);	1372	\& ev_signal_start (loop, &sigint_cb);
		1373	.Ve
		1374	.ie n .Sh """ev_stat"" \- did the file attributes just change?"
		1375	.el .Sh "\f(CWev_stat\fP \- did the file attributes just change?"
		1376	.IX Subsection "ev_stat - did the file attributes just change?"
		1377	This watches a filesystem path for attribute changes. That is, it calls
		1378	\&\f(CW\(C`stat\(C'\fR regularly (or when the \s-1OS\s0 says it changed) and sees if it changed
		1379	compared to the last time, invoking the callback if it did.
		1380	.PP
		1381	The path does not need to exist: changing from \(L"path exists\(R" to \*(L"path does
		1382	not exist\(R" is a status change like any other. The condition \(L"path does
		1383	not exist\(R" is signified by the \f(CW\(C`st_nlink\*(C'\fR field being zero (which is
		1384	otherwise always forced to be at least one) and all the other fields of
		1385	the stat buffer having unspecified contents.
		1386	.PP
		1387	Since there is no standard to do this, the portable implementation simply
		1388	calls \f(CW\(C`stat (2)\(C'\fR regularly on the path to see if it changed somehow. You
		1389	can specify a recommended polling interval for this case. If you specify
		1390	a polling interval of \f(CW0\fR (highly recommended!) then a \fIsuitable,
		1391	unspecified default\fR value will be used (which you can expect to be around
		1392	five seconds, although this might change dynamically). Libev will also
		1393	impose a minimum interval which is currently around \f(CW0.1\fR, but thats
		1394	usually overkill.
		1395	.PP
		1396	This watcher type is not meant for massive numbers of stat watchers,
		1397	as even with OS-supported change notifications, this can be
		1398	resource\-intensive.
		1399	.PP
		1400	At the time of this writing, only the Linux inotify interface is
		1401	implemented (implementing kqueue support is left as an exercise for the
		1402	reader). Inotify will be used to give hints only and should not change the
		1403	semantics of \f(CW\(C`ev_stat\(C'\fR watchers, which means that libev sometimes needs
		1404	to fall back to regular polling again even with inotify, but changes are
		1405	usually detected immediately, and if the file exists there will be no
		1406	polling.
		1407	.IP "ev_stat_init (ev_stat , callback, const char path, ev_tstamp interval)" 4
		1408	.IX Item "ev_stat_init (ev_stat , callback, const char path, ev_tstamp interval)"
		1409	.PD 0
		1410	.IP "ev_stat_set (ev_stat , const char path, ev_tstamp interval)" 4
		1411	.IX Item "ev_stat_set (ev_stat , const char path, ev_tstamp interval)"
		1412	.PD
		1413	Configures the watcher to wait for status changes of the given
		1414	\&\f(CW\(C`path\(C'\fR. The \f(CW\(C`interval\(C'\fR is a hint on how quickly a change is expected to
		1415	be detected and should normally be specified as \f(CW0\fR to let libev choose
		1416	a suitable value. The memory pointed to by \f(CW\(C`path\(C'\fR must point to the same
		1417	path for as long as the watcher is active.
		1418	.Sp
		1419	The callback will be receive \f(CW\(C`EV_STAT\(C'\fR when a change was detected,
		1420	relative to the attributes at the time the watcher was started (or the
		1421	last change was detected).
		1422	.IP "ev_stat_stat (ev_stat *)" 4
		1423	.IX Item "ev_stat_stat (ev_stat *)"
		1424	Updates the stat buffer immediately with new values. If you change the
		1425	watched path in your callback, you could call this fucntion to avoid
		1426	detecting this change (while introducing a race condition). Can also be
		1427	useful simply to find out the new values.
		1428	.IP "ev_statdata attr [read\-only]" 4
		1429	.IX Item "ev_statdata attr [read-only]"
		1430	The most-recently detected attributes of the file. Although the type is of
		1431	\&\f(CW\(C`ev_statdata\(C'\fR, this is usually the (or one of the) \f(CW\(C`struct stat\(C'\fR types
		1432	suitable for your system. If the \f(CW\(C`st_nlink\(C'\fR member is \f(CW0\fR, then there
		1433	was some error while \f(CW\(C`stat\(C'\fRing the file.
		1434	.IP "ev_statdata prev [read\-only]" 4
		1435	.IX Item "ev_statdata prev [read-only]"
		1436	The previous attributes of the file. The callback gets invoked whenever
		1437	\&\f(CW\(C`prev\(C'\fR != \f(CW\(C`attr\(C'\fR.
		1438	.IP "ev_tstamp interval [read\-only]" 4
		1439	.IX Item "ev_tstamp interval [read-only]"
		1440	The specified interval.
		1441	.IP "const char *path [read\-only]" 4
		1442	.IX Item "const char *path [read-only]"
		1443	The filesystem path that is being watched.
		1444	.PP
		1445	Example: Watch \f(CW\(C`/etc/passwd\(C'\fR for attribute changes.
		1446	.PP
		1447	.Vb 15
		1448	\& static void
		1449	\& passwd_cb (struct ev_loop loop, ev_stat w, int revents)
		1450	\& {
		1451	\& /* /etc/passwd changed in some way */
		1452	\& if (w->attr.st_nlink)
		1453	\& {
		1454	\& printf ("passwd current size %ld\en", (long)w->attr.st_size);
		1455	\& printf ("passwd current atime %ld\en", (long)w->attr.st_mtime);
		1456	\& printf ("passwd current mtime %ld\en", (long)w->attr.st_mtime);
		1457	\& }
		1458	\& else
		1459	\& /* you shalt not abuse printf for puts */
		1460	\& puts ("wow, /etc/passwd is not there, expect problems. "
		1461	\& "if this is windows, they already arrived\en");
		1462	\& }
		1463	.Ve
		1464	.PP
		1465	.Vb 2
		1466	\& ...
		1467	\& ev_stat passwd;
		1468	.Ve
		1469	.PP
		1470	.Vb 2
		1471	\& ev_stat_init (&passwd, passwd_cb, "/etc/passwd");
		1472	\& ev_stat_start (loop, &passwd);
1197	.Ve	1473	.Ve
1198	.ie n .Sh """ev_idle"" \- when you've got nothing better to do..."	1474	.ie n .Sh """ev_idle"" \- when you've got nothing better to do..."
1199	.el .Sh "\f(CWev_idle\fP \- when you've got nothing better to do..."	1475	.el .Sh "\f(CWev_idle\fP \- when you've got nothing better to do..."
1200	.IX Subsection "ev_idle - when you've got nothing better to do..."	1476	.IX Subsection "ev_idle - when you've got nothing better to do..."
1201	Idle watchers trigger events when there are no other events are pending	1477	Idle watchers trigger events when there are no other events are pending
…		…
1217	.IX Item "ev_idle_init (ev_signal *, callback)"	1493	.IX Item "ev_idle_init (ev_signal *, callback)"
1218	Initialises and configures the idle watcher \- it has no parameters of any	1494	Initialises and configures the idle watcher \- it has no parameters of any
1219	kind. There is a \f(CW\(C`ev_idle_set\(C'\fR macro, but using it is utterly pointless,	1495	kind. There is a \f(CW\(C`ev_idle_set\(C'\fR macro, but using it is utterly pointless,
1220	believe me.	1496	believe me.
1221	.PP	1497	.PP
1222	Example: dynamically allocate an \f(CW\(C`ev_idle\(C'\fR, start it, and in the	1498	Example: Dynamically allocate an \f(CW\(C`ev_idle\(C'\fR watcher, start it, and in the
1223	callback, free it. Alos, use no error checking, as usual.	1499	callback, free it. Also, use no error checking, as usual.
1224	.PP	1500	.PP
1225	.Vb 7	1501	.Vb 7
1226	\& static void	1502	\& static void
1227	\& idle_cb (struct ev_loop loop, struct ev_idle w, int revents)	1503	\& idle_cb (struct ev_loop loop, struct ev_idle w, int revents)
1228	\& {	1504	\& {
…		…
1242	.IX Subsection "ev_prepare and ev_check - customise your event loop!"	1518	.IX Subsection "ev_prepare and ev_check - customise your event loop!"
1243	Prepare and check watchers are usually (but not always) used in tandem:	1519	Prepare and check watchers are usually (but not always) used in tandem:
1244	prepare watchers get invoked before the process blocks and check watchers	1520	prepare watchers get invoked before the process blocks and check watchers
1245	afterwards.	1521	afterwards.
1246	.PP	1522	.PP
		1523	You \fImust not\fR call \f(CW\(C`ev_loop\(C'\fR or similar functions that enter
		1524	the current event loop from either \f(CW\(C`ev_prepare\(C'\fR or \f(CW\(C`ev_check\(C'\fR
		1525	watchers. Other loops than the current one are fine, however. The
		1526	rationale behind this is that you do not need to check for recursion in
		1527	those watchers, i.e. the sequence will always be \f(CW\(C`ev_prepare\(C'\fR, blocking,
		1528	\&\f(CW\(C`ev_check\(C'\fR so if you have one watcher of each kind they will always be
		1529	called in pairs bracketing the blocking call.
		1530	.PP
1247	Their main purpose is to integrate other event mechanisms into libev and	1531	Their main purpose is to integrate other event mechanisms into libev and
1248	their use is somewhat advanced. This could be used, for example, to track	1532	their use is somewhat advanced. This could be used, for example, to track
1249	variable changes, implement your own watchers, integrate net-snmp or a	1533	variable changes, implement your own watchers, integrate net-snmp or a
1250	coroutine library and lots more.	1534	coroutine library and lots more. They are also occasionally useful if
		1535	you cache some data and want to flush it before blocking (for example,
		1536	in X programs you might want to do an \f(CW\(C`XFlush ()\(C'\fR in an \f(CW\(C`ev_prepare\(C'\fR
		1537	watcher).
1251	.PP	1538	.PP
1252	This is done by examining in each prepare call which file descriptors need	1539	This is done by examining in each prepare call which file descriptors need
1253	to be watched by the other library, registering \f(CW\(C`ev_io\(C'\fR watchers for	1540	to be watched by the other library, registering \f(CW\(C`ev_io\(C'\fR watchers for
1254	them and starting an \f(CW\(C`ev_timer\(C'\fR watcher for any timeouts (many libraries	1541	them and starting an \f(CW\(C`ev_timer\(C'\fR watcher for any timeouts (many libraries
1255	provide just this functionality). Then, in the check watcher you check for	1542	provide just this functionality). Then, in the check watcher you check for
…		…
1274	.PD	1561	.PD
1275	Initialises and configures the prepare or check watcher \- they have no	1562	Initialises and configures the prepare or check watcher \- they have no
1276	parameters of any kind. There are \f(CW\(C`ev_prepare_set\(C'\fR and \f(CW\(C`ev_check_set\(C'\fR	1563	parameters of any kind. There are \f(CW\(C`ev_prepare_set\(C'\fR and \f(CW\(C`ev_check_set\(C'\fR
1277	macros, but using them is utterly, utterly and completely pointless.	1564	macros, but using them is utterly, utterly and completely pointless.
1278	.PP	1565	.PP
1279	Example: TODO.	1566	Example: To include a library such as adns, you would add \s-1IO\s0 watchers
		1567	and a timeout watcher in a prepare handler, as required by libadns, and
		1568	in a check watcher, destroy them and call into libadns. What follows is
		1569	pseudo-code only of course:
		1570	.PP
		1571	.Vb 2
		1572	\& static ev_io iow [nfd];
		1573	\& static ev_timer tw;
		1574	.Ve
		1575	.PP
		1576	.Vb 9
		1577	\& static void
		1578	\& io_cb (ev_loop loop, ev_io w, int revents)
		1579	\& {
		1580	\& // set the relevant poll flags
		1581	\& // could also call adns_processreadable etc. here
		1582	\& struct pollfd fd = (struct pollfd )w->data;
		1583	\& if (revents & EV_READ ) fd->revents \|= fd->events & POLLIN;
		1584	\& if (revents & EV_WRITE) fd->revents \|= fd->events & POLLOUT;
		1585	\& }
		1586	.Ve
		1587	.PP
		1588	.Vb 7
		1589	\& // create io watchers for each fd and a timer before blocking
		1590	\& static void
		1591	\& adns_prepare_cb (ev_loop loop, ev_prepare w, int revents)
		1592	\& {
		1593	\& int timeout = 3600000;truct pollfd fds [nfd];
		1594	\& // actual code will need to loop here and realloc etc.
		1595	\& adns_beforepoll (ads, fds, &nfd, &timeout, timeval_from (ev_time ()));
		1596	.Ve
		1597	.PP
		1598	.Vb 3
		1599	\& /* the callback is illegal, but won't be called as we stop during check */
		1600	\& ev_timer_init (&tw, 0, timeout * 1e-3);
		1601	\& ev_timer_start (loop, &tw);
		1602	.Ve
		1603	.PP
		1604	.Vb 6
		1605	\& // create on ev_io per pollfd
		1606	\& for (int i = 0; i < nfd; ++i)
		1607	\& {
		1608	\& ev_io_init (iow + i, io_cb, fds [i].fd,
		1609	\& ((fds [i].events & POLLIN ? EV_READ : 0)
		1610	\& \| (fds [i].events & POLLOUT ? EV_WRITE : 0)));
		1611	.Ve
		1612	.PP
		1613	.Vb 5
		1614	\& fds [i].revents = 0;
		1615	\& iow [i].data = fds + i;
		1616	\& ev_io_start (loop, iow + i);
		1617	\& }
		1618	\& }
		1619	.Ve
		1620	.PP
		1621	.Vb 5
		1622	\& // stop all watchers after blocking
		1623	\& static void
		1624	\& adns_check_cb (ev_loop loop, ev_check w, int revents)
		1625	\& {
		1626	\& ev_timer_stop (loop, &tw);
		1627	.Ve
		1628	.PP
		1629	.Vb 2
		1630	\& for (int i = 0; i < nfd; ++i)
		1631	\& ev_io_stop (loop, iow + i);
		1632	.Ve
		1633	.PP
		1634	.Vb 2
		1635	\& adns_afterpoll (adns, fds, nfd, timeval_from (ev_now (loop));
		1636	\& }
		1637	.Ve
1280	.ie n .Sh """ev_embed"" \- when one backend isn't enough..."	1638	.ie n .Sh """ev_embed"" \- when one backend isn't enough..."
1281	.el .Sh "\f(CWev_embed\fP \- when one backend isn't enough..."	1639	.el .Sh "\f(CWev_embed\fP \- when one backend isn't enough..."
1282	.IX Subsection "ev_embed - when one backend isn't enough..."	1640	.IX Subsection "ev_embed - when one backend isn't enough..."
1283	This is a rather advanced watcher type that lets you embed one event loop	1641	This is a rather advanced watcher type that lets you embed one event loop
1284	into another (currently only \f(CW\(C`ev_io\(C'\fR events are supported in the embedded	1642	into another (currently only \f(CW\(C`ev_io\(C'\fR events are supported in the embedded
…		…
1367	.IP "ev_embed_sweep (loop, ev_embed *)" 4	1725	.IP "ev_embed_sweep (loop, ev_embed *)" 4
1368	.IX Item "ev_embed_sweep (loop, ev_embed *)"	1726	.IX Item "ev_embed_sweep (loop, ev_embed *)"
1369	Make a single, non-blocking sweep over the embedded loop. This works	1727	Make a single, non-blocking sweep over the embedded loop. This works
1370	similarly to \f(CW\(C`ev_loop (embedded_loop, EVLOOP_NONBLOCK)\(C'\fR, but in the most	1728	similarly to \f(CW\(C`ev_loop (embedded_loop, EVLOOP_NONBLOCK)\(C'\fR, but in the most
1371	apropriate way for embedded loops.	1729	apropriate way for embedded loops.
		1730	.IP "struct ev_loop *loop [read\-only]" 4
		1731	.IX Item "struct ev_loop *loop [read-only]"
		1732	The embedded event loop.
		1733	.ie n .Sh """ev_fork"" \- the audacity to resume the event loop after a fork"
		1734	.el .Sh "\f(CWev_fork\fP \- the audacity to resume the event loop after a fork"
		1735	.IX Subsection "ev_fork - the audacity to resume the event loop after a fork"
		1736	Fork watchers are called when a \f(CW\(C`fork ()\(C'\fR was detected (usually because
		1737	whoever is a good citizen cared to tell libev about it by calling
		1738	\&\f(CW\(C`ev_default_fork\(C'\fR or \f(CW\(C`ev_loop_fork\(C'\fR). The invocation is done before the
		1739	event loop blocks next and before \f(CW\(C`ev_check\(C'\fR watchers are being called,
		1740	and only in the child after the fork. If whoever good citizen calling
		1741	\&\f(CW\(C`ev_default_fork\(C'\fR cheats and calls it in the wrong process, the fork
		1742	handlers will be invoked, too, of course.
		1743	.IP "ev_fork_init (ev_signal *, callback)" 4
		1744	.IX Item "ev_fork_init (ev_signal *, callback)"
		1745	Initialises and configures the fork watcher \- it has no parameters of any
		1746	kind. There is a \f(CW\(C`ev_fork_set\(C'\fR macro, but using it is utterly pointless,
		1747	believe me.
1372	.SH "OTHER FUNCTIONS"	1748	.SH "OTHER FUNCTIONS"
1373	.IX Header "OTHER FUNCTIONS"	1749	.IX Header "OTHER FUNCTIONS"
1374	There are some other functions of possible interest. Described. Here. Now.	1750	There are some other functions of possible interest. Described. Here. Now.
1375	.IP "ev_once (loop, int fd, int events, ev_tstamp timeout, callback)" 4	1751	.IP "ev_once (loop, int fd, int events, ev_tstamp timeout, callback)" 4
1376	.IX Item "ev_once (loop, int fd, int events, ev_tstamp timeout, callback)"	1752	.IX Item "ev_once (loop, int fd, int events, ev_tstamp timeout, callback)"
…		…
1515	\&\f(CW\(C`ev_TYPE_again\(C'\fR function.	1891	\&\f(CW\(C`ev_TYPE_again\(C'\fR function.
1516	.ie n .IP "w\->sweep () ""ev::embed"" only" 4	1892	.ie n .IP "w\->sweep () ""ev::embed"" only" 4
1517	.el .IP "w\->sweep () \f(CWev::embed\fR only" 4	1893	.el .IP "w\->sweep () \f(CWev::embed\fR only" 4
1518	.IX Item "w->sweep () ev::embed only"	1894	.IX Item "w->sweep () ev::embed only"
1519	Invokes \f(CW\(C`ev_embed_sweep\(C'\fR.	1895	Invokes \f(CW\(C`ev_embed_sweep\(C'\fR.
		1896	.ie n .IP "w\->update () ""ev::stat"" only" 4
		1897	.el .IP "w\->update () \f(CWev::stat\fR only" 4
		1898	.IX Item "w->update () ev::stat only"
		1899	Invokes \f(CW\(C`ev_stat_stat\(C'\fR.
1520	.RE	1900	.RE
1521	.RS 4	1901	.RS 4
1522	.RE	1902	.RE
1523	.PP	1903	.PP
1524	Example: Define a class with an \s-1IO\s0 and idle watcher, start one of them in	1904	Example: Define a class with an \s-1IO\s0 and idle watcher, start one of them in
…		…
1541	\& : io (this, &myclass::io_cb),	1921	\& : io (this, &myclass::io_cb),
1542	\& idle (this, &myclass::idle_cb)	1922	\& idle (this, &myclass::idle_cb)
1543	\& {	1923	\& {
1544	\& io.start (fd, ev::READ);	1924	\& io.start (fd, ev::READ);
1545	\& }	1925	\& }
		1926	.Ve
		1927	.SH "MACRO MAGIC"
		1928	.IX Header "MACRO MAGIC"
		1929	Libev can be compiled with a variety of options, the most fundemantal is
		1930	\&\f(CW\(C`EV_MULTIPLICITY\(C'\fR. This option determines wether (most) functions and
		1931	callbacks have an initial \f(CW\(C`struct ev_loop \*(C'\fR argument.
		1932	.PP
		1933	To make it easier to write programs that cope with either variant, the
		1934	following macros are defined:
		1935	.ie n .IP """EV_A""\fR, \f(CW""EV_A_""" 4
		1936	.el .IP "\f(CWEV_A\fR, \f(CWEV_A_\fR" 4
		1937	.IX Item "EV_A, EV_A_"
		1938	This provides the loop \fIargument\fR for functions, if one is required (\*(L"ev
		1939	loop argument\(R"). The \f(CW\(C`EV_A\*(C'\fR form is used when this is the sole argument,
		1940	\&\f(CW\(C`EV_A_\(C'\fR is used when other arguments are following. Example:
		1941	.Sp
		1942	.Vb 3
		1943	\& ev_unref (EV_A);
		1944	\& ev_timer_add (EV_A_ watcher);
		1945	\& ev_loop (EV_A_ 0);
		1946	.Ve
		1947	.Sp
		1948	It assumes the variable \f(CW\(C`loop\(C'\fR of type \f(CW\(C`struct ev_loop \*(C'\fR is in scope,
		1949	which is often provided by the following macro.
		1950	.ie n .IP """EV_P""\fR, \f(CW""EV_P_""" 4
		1951	.el .IP "\f(CWEV_P\fR, \f(CWEV_P_\fR" 4
		1952	.IX Item "EV_P, EV_P_"
		1953	This provides the loop \fIparameter\fR for functions, if one is required (\*(L"ev
		1954	loop parameter\(R"). The \f(CW\(C`EV_P\*(C'\fR form is used when this is the sole parameter,
		1955	\&\f(CW\(C`EV_P_\(C'\fR is used when other parameters are following. Example:
		1956	.Sp
		1957	.Vb 2
		1958	\& // this is how ev_unref is being declared
		1959	\& static void ev_unref (EV_P);
		1960	.Ve
		1961	.Sp
		1962	.Vb 2
		1963	\& // this is how you can declare your typical callback
		1964	\& static void cb (EV_P_ ev_timer *w, int revents)
		1965	.Ve
		1966	.Sp
		1967	It declares a parameter \f(CW\(C`loop\(C'\fR of type \f(CW\(C`struct ev_loop \*(C'\fR, quite
		1968	suitable for use with \f(CW\(C`EV_A\(C'\fR.
		1969	.ie n .IP """EV_DEFAULT""\fR, \f(CW""EV_DEFAULT_""" 4
		1970	.el .IP "\f(CWEV_DEFAULT\fR, \f(CWEV_DEFAULT_\fR" 4
		1971	.IX Item "EV_DEFAULT, EV_DEFAULT_"
		1972	Similar to the other two macros, this gives you the value of the default
		1973	loop, if multiple loops are supported (\(L"ev loop default\(R").
		1974	.PP
		1975	Example: Declare and initialise a check watcher, working regardless of
		1976	wether multiple loops are supported or not.
		1977	.PP
		1978	.Vb 5
		1979	\& static void
		1980	\& check_cb (EV_P_ ev_timer *w, int revents)
		1981	\& {
		1982	\& ev_check_stop (EV_A_ w);
		1983	\& }
		1984	.Ve
		1985	.PP
		1986	.Vb 4
		1987	\& ev_check check;
		1988	\& ev_check_init (&check, check_cb);
		1989	\& ev_check_start (EV_DEFAULT_ &check);
		1990	\& ev_loop (EV_DEFAULT_ 0);
1546	.Ve	1991	.Ve
1547	.SH "EMBEDDING"	1992	.SH "EMBEDDING"
1548	.IX Header "EMBEDDING"	1993	.IX Header "EMBEDDING"
1549	Libev can (and often is) directly embedded into host	1994	Libev can (and often is) directly embedded into host
1550	applications. Examples of applications that embed it include the Deliantra	1995	applications. Examples of applications that embed it include the Deliantra
…		…
1599	.Vb 1	2044	.Vb 1
1600	\& ev_win32.c required on win32 platforms only	2045	\& ev_win32.c required on win32 platforms only
1601	.Ve	2046	.Ve
1602	.PP	2047	.PP
1603	.Vb 5	2048	.Vb 5
1604	\& ev_select.c only when select backend is enabled (which is is by default)	2049	\& ev_select.c only when select backend is enabled (which is by default)
1605	\& ev_poll.c only when poll backend is enabled (disabled by default)	2050	\& ev_poll.c only when poll backend is enabled (disabled by default)
1606	\& ev_epoll.c only when the epoll backend is enabled (disabled by default)	2051	\& ev_epoll.c only when the epoll backend is enabled (disabled by default)
1607	\& ev_kqueue.c only when the kqueue backend is enabled (disabled by default)	2052	\& ev_kqueue.c only when the kqueue backend is enabled (disabled by default)
1608	\& ev_port.c only when the solaris port backend is enabled (disabled by default)	2053	\& ev_port.c only when the solaris port backend is enabled (disabled by default)
1609	.Ve	2054	.Ve
1610	.PP	2055	.PP
1611	\&\fIev.c\fR includes the backend files directly when enabled, so you only need	2056	\&\fIev.c\fR includes the backend files directly when enabled, so you only need
1612	to compile a single file.	2057	to compile this single file.
1613	.PP	2058	.PP
1614	\fI\s-1LIBEVENT\s0 \s-1COMPATIBILITY\s0 \s-1API\s0\fR	2059	\fI\s-1LIBEVENT\s0 \s-1COMPATIBILITY\s0 \s-1API\s0\fR
1615	.IX Subsection "LIBEVENT COMPATIBILITY API"	2060	.IX Subsection "LIBEVENT COMPATIBILITY API"
1616	.PP	2061	.PP
1617	To include the libevent compatibility \s-1API\s0, also include:	2062	To include the libevent compatibility \s-1API\s0, also include:
…		…
1638	\fI\s-1AUTOCONF\s0 \s-1SUPPORT\s0\fR	2083	\fI\s-1AUTOCONF\s0 \s-1SUPPORT\s0\fR
1639	.IX Subsection "AUTOCONF SUPPORT"	2084	.IX Subsection "AUTOCONF SUPPORT"
1640	.PP	2085	.PP
1641	Instead of using \f(CW\(C`EV_STANDALONE=1\(C'\fR and providing your config in	2086	Instead of using \f(CW\(C`EV_STANDALONE=1\(C'\fR and providing your config in
1642	whatever way you want, you can also \f(CW\(C`m4_include([libev.m4])\(C'\fR in your	2087	whatever way you want, you can also \f(CW\(C`m4_include([libev.m4])\(C'\fR in your
1643	\&\fIconfigure.ac\fR and leave \f(CW\(C`EV_STANDALONE\(C'\fR off. \fIev.c\fR will then include	2088	\&\fIconfigure.ac\fR and leave \f(CW\(C`EV_STANDALONE\(C'\fR undefined. \fIev.c\fR will then
1644	\&\fIconfig.h\fR and configure itself accordingly.	2089	include \fIconfig.h\fR and configure itself accordingly.
1645	.PP	2090	.PP
1646	For this of course you need the m4 file:	2091	For this of course you need the m4 file:
1647	.PP	2092	.PP
1648	.Vb 1	2093	.Vb 1
1649	\& libev.m4	2094	\& libev.m4
…		…
1730	otherwise another method will be used as fallback. This is the preferred	2175	otherwise another method will be used as fallback. This is the preferred
1731	backend for Solaris 10 systems.	2176	backend for Solaris 10 systems.
1732	.IP "\s-1EV_USE_DEVPOLL\s0" 4	2177	.IP "\s-1EV_USE_DEVPOLL\s0" 4
1733	.IX Item "EV_USE_DEVPOLL"	2178	.IX Item "EV_USE_DEVPOLL"
1734	reserved for future expansion, works like the \s-1USE\s0 symbols above.	2179	reserved for future expansion, works like the \s-1USE\s0 symbols above.
		2180	.IP "\s-1EV_USE_INOTIFY\s0" 4
		2181	.IX Item "EV_USE_INOTIFY"
		2182	If defined to be \f(CW1\fR, libev will compile in support for the Linux inotify
		2183	interface to speed up \f(CW\(C`ev_stat\(C'\fR watchers. Its actual availability will
		2184	be detected at runtime.
1735	.IP "\s-1EV_H\s0" 4	2185	.IP "\s-1EV_H\s0" 4
1736	.IX Item "EV_H"	2186	.IX Item "EV_H"
1737	The name of the \fIev.h\fR header file used to include it. The default if	2187	The name of the \fIev.h\fR header file used to include it. The default if
1738	undefined is \f(CW\(C`<ev.h>\(C'\fR in \fIevent.h\fR and \f(CW"ev.h"\fR in \fIev.c\fR. This	2188	undefined is \f(CW\(C`<ev.h>\(C'\fR in \fIevent.h\fR and \f(CW"ev.h"\fR in \fIev.c\fR. This
1739	can be used to virtually rename the \fIev.h\fR header file in case of conflicts.	2189	can be used to virtually rename the \fIev.h\fR header file in case of conflicts.
…		…
1757	If undefined or defined to \f(CW1\fR, then all event-loop-specific functions	2207	If undefined or defined to \f(CW1\fR, then all event-loop-specific functions
1758	will have the \f(CW\(C`struct ev_loop \*(C'\fR as first argument, and you can create	2208	will have the \f(CW\(C`struct ev_loop \*(C'\fR as first argument, and you can create
1759	additional independent event loops. Otherwise there will be no support	2209	additional independent event loops. Otherwise there will be no support
1760	for multiple event loops and there is no first event loop pointer	2210	for multiple event loops and there is no first event loop pointer
1761	argument. Instead, all functions act on the single default loop.	2211	argument. Instead, all functions act on the single default loop.
1762	.IP "\s-1EV_PERIODICS\s0" 4	2212	.IP "\s-1EV_PERIODIC_ENABLE\s0" 4
1763	.IX Item "EV_PERIODICS"	2213	.IX Item "EV_PERIODIC_ENABLE"
1764	If undefined or defined to be \f(CW1\fR, then periodic timers are supported,	2214	If undefined or defined to be \f(CW1\fR, then periodic timers are supported. If
1765	otherwise not. This saves a few kb of code.	2215	defined to be \f(CW0\fR, then they are not. Disabling them saves a few kB of
		2216	code.
		2217	.IP "\s-1EV_EMBED_ENABLE\s0" 4
		2218	.IX Item "EV_EMBED_ENABLE"
		2219	If undefined or defined to be \f(CW1\fR, then embed watchers are supported. If
		2220	defined to be \f(CW0\fR, then they are not.
		2221	.IP "\s-1EV_STAT_ENABLE\s0" 4
		2222	.IX Item "EV_STAT_ENABLE"
		2223	If undefined or defined to be \f(CW1\fR, then stat watchers are supported. If
		2224	defined to be \f(CW0\fR, then they are not.
		2225	.IP "\s-1EV_FORK_ENABLE\s0" 4
		2226	.IX Item "EV_FORK_ENABLE"
		2227	If undefined or defined to be \f(CW1\fR, then fork watchers are supported. If
		2228	defined to be \f(CW0\fR, then they are not.
		2229	.IP "\s-1EV_MINIMAL\s0" 4
		2230	.IX Item "EV_MINIMAL"
		2231	If you need to shave off some kilobytes of code at the expense of some
		2232	speed, define this symbol to \f(CW1\fR. Currently only used for gcc to override
		2233	some inlining decisions, saves roughly 30% codesize of amd64.
		2234	.IP "\s-1EV_PID_HASHSIZE\s0" 4
		2235	.IX Item "EV_PID_HASHSIZE"
		2236	\&\f(CW\(C`ev_child\(C'\fR watchers use a small hash table to distribute workload by
		2237	pid. The default size is \f(CW16\fR (or \f(CW1\fR with \f(CW\(C`EV_MINIMAL\(C'\fR), usually more
		2238	than enough. If you need to manage thousands of children you might want to
		2239	increase this value (\fImust\fR be a power of two).
		2240	.IP "\s-1EV_INOTIFY_HASHSIZE\s0" 4
		2241	.IX Item "EV_INOTIFY_HASHSIZE"
		2242	\&\f(CW\(C`ev_staz\(C'\fR watchers use a small hash table to distribute workload by
		2243	inotify watch id. The default size is \f(CW16\fR (or \f(CW1\fR with \f(CW\(C`EV_MINIMAL\(C'\fR),
		2244	usually more than enough. If you need to manage thousands of \f(CW\(C`ev_stat\(C'\fR
		2245	watchers you might want to increase this value (\fImust\fR be a power of
		2246	two).
1766	.IP "\s-1EV_COMMON\s0" 4	2247	.IP "\s-1EV_COMMON\s0" 4
1767	.IX Item "EV_COMMON"	2248	.IX Item "EV_COMMON"
1768	By default, all watchers have a \f(CW\(C`void data\*(C'\fR member. By redefining	2249	By default, all watchers have a \f(CW\(C`void data\*(C'\fR member. By redefining
1769	this macro to a something else you can include more and other types of	2250	this macro to a something else you can include more and other types of
1770	members. You have to define it each time you include one of the files,	2251	members. You have to define it each time you include one of the files,
…		…
1775	.Vb 3	2256	.Vb 3
1776	\& #define EV_COMMON \e	2257	\& #define EV_COMMON \e
1777	\& SV self; / contains this struct */ \e	2258	\& SV self; / contains this struct */ \e
1778	\& SV cb_sv, fh /* note no trailing ";" */	2259	\& SV cb_sv, fh /* note no trailing ";" */
1779	.Ve	2260	.Ve
1780	.IP "\s-1EV_CB_DECLARE\s0(type)" 4	2261	.IP "\s-1EV_CB_DECLARE\s0 (type)" 4
1781	.IX Item "EV_CB_DECLARE(type)"	2262	.IX Item "EV_CB_DECLARE (type)"
1782	.PD 0	2263	.PD 0
1783	.IP "\s-1EV_CB_INVOKE\s0(watcher,revents)" 4	2264	.IP "\s-1EV_CB_INVOKE\s0 (watcher, revents)" 4
1784	.IX Item "EV_CB_INVOKE(watcher,revents)"	2265	.IX Item "EV_CB_INVOKE (watcher, revents)"
1785	.IP "ev_set_cb(ev,cb)" 4	2266	.IP "ev_set_cb (ev, cb)" 4
1786	.IX Item "ev_set_cb(ev,cb)"	2267	.IX Item "ev_set_cb (ev, cb)"
1787	.PD	2268	.PD
1788	Can be used to change the callback member declaration in each watcher,	2269	Can be used to change the callback member declaration in each watcher,
1789	and the way callbacks are invoked and set. Must expand to a struct member	2270	and the way callbacks are invoked and set. Must expand to a struct member
1790	definition and a statement, respectively. See the \fIev.v\fR header file for	2271	definition and a statement, respectively. See the \fIev.v\fR header file for
1791	their default definitions. One possible use for overriding these is to	2272	their default definitions. One possible use for overriding these is to
1792	avoid the ev_loop pointer as first argument in all cases, or to use method	2273	avoid the \f(CW\(C`struct ev_loop \*(C'\fR as first argument in all cases, or to use
1793	calls instead of plain function calls in \*(C+.	2274	method calls instead of plain function calls in \*(C+.
1794	.Sh "\s-1EXAMPLES\s0"	2275	.Sh "\s-1EXAMPLES\s0"
1795	.IX Subsection "EXAMPLES"	2276	.IX Subsection "EXAMPLES"
1796	For a real-world example of a program the includes libev	2277	For a real-world example of a program the includes libev
1797	verbatim, you can have a look at the \s-1EV\s0 perl module	2278	verbatim, you can have a look at the \s-1EV\s0 perl module
1798	(<http://software.schmorp.de/pkg/EV.html>). It has the libev files in	2279	(<http://software.schmorp.de/pkg/EV.html>). It has the libev files in
…		…
1819	.Sp	2300	.Sp
1820	.Vb 2	2301	.Vb 2
1821	\& #include "ev_cpp.h"	2302	\& #include "ev_cpp.h"
1822	\& #include "ev.c"	2303	\& #include "ev.c"
1823	.Ve	2304	.Ve
		2305	.SH "COMPLEXITIES"
		2306	.IX Header "COMPLEXITIES"
		2307	In this section the complexities of (many of) the algorithms used inside
		2308	libev will be explained. For complexity discussions about backends see the
		2309	documentation for \f(CW\(C`ev_default_init\(C'\fR.
		2310	.RS 4
		2311	.IP "Starting and stopping timer/periodic watchers: O(log skipped_other_timers)" 4
		2312	.IX Item "Starting and stopping timer/periodic watchers: O(log skipped_other_timers)"
		2313	.PD 0
		2314	.IP "Changing timer/periodic watchers (by autorepeat, again): O(log skipped_other_timers)" 4
		2315	.IX Item "Changing timer/periodic watchers (by autorepeat, again): O(log skipped_other_timers)"
		2316	.IP "Starting io/check/prepare/idle/signal/child watchers: O(1)" 4
		2317	.IX Item "Starting io/check/prepare/idle/signal/child watchers: O(1)"
		2318	.IP "Stopping check/prepare/idle watchers: O(1)" 4
		2319	.IX Item "Stopping check/prepare/idle watchers: O(1)"
		2320	.IP "Stopping an io/signal/child watcher: O(number_of_watchers_for_this_(fd/signal/pid % \s-1EV_PID_HASHSIZE\s0))" 4
		2321	.IX Item "Stopping an io/signal/child watcher: O(number_of_watchers_for_this_(fd/signal/pid % EV_PID_HASHSIZE))"
		2322	.IP "Finding the next timer per loop iteration: O(1)" 4
		2323	.IX Item "Finding the next timer per loop iteration: O(1)"
		2324	.IP "Each change on a file descriptor per loop iteration: O(number_of_watchers_for_this_fd)" 4
		2325	.IX Item "Each change on a file descriptor per loop iteration: O(number_of_watchers_for_this_fd)"
		2326	.IP "Activating one watcher: O(1)" 4
		2327	.IX Item "Activating one watcher: O(1)"
		2328	.RE
		2329	.RS 4
		2330	.PD
1824	.SH "AUTHOR"	2331	.SH "AUTHOR"
1825	.IX Header "AUTHOR"	2332	.IX Header "AUTHOR"
1826	Marc Lehmann <libev@schmorp.de>.	2333	Marc Lehmann <libev@schmorp.de>.

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Comparing libev/ev.3 (file contents): Revision 1.17 by root, Sat Nov 24 16:31:45 2007 UTC vs. Revision 1.30 by root, Wed Nov 28 11:27:29 2007 UTC

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Comparing libev/ev.3 (file contents):
Revision 1.17 by root, Sat Nov 24 16:31:45 2007 UTC vs.
Revision 1.30 by root, Wed Nov 28 11:27:29 2007 UTC