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4	<head>	4	<head>
5	<title>libev</title>	5	<title>libev</title>
6	<meta name="description" content="Pod documentation for libev" />	6	<meta name="description" content="Pod documentation for libev" />
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12	<body>	12	<body>
13	<div class="pod">	13	<div class="pod">
14	<!-- INDEX START -->	14	<!-- INDEX START -->
…		…
17	<ul><li><a href="#NAME">NAME</a></li>	17	<ul><li><a href="#NAME">NAME</a></li>
18	<li><a href="#SYNOPSIS">SYNOPSIS</a></li>	18	<li><a href="#SYNOPSIS">SYNOPSIS</a></li>
19	<li><a href="#DESCRIPTION">DESCRIPTION</a></li>	19	<li><a href="#DESCRIPTION">DESCRIPTION</a></li>
20	<li><a href="#FEATURES">FEATURES</a></li>	20	<li><a href="#FEATURES">FEATURES</a></li>
21	<li><a href="#CONVENTIONS">CONVENTIONS</a></li>	21	<li><a href="#CONVENTIONS">CONVENTIONS</a></li>
		22	<li><a href="#TIME_REPRESENTATION">TIME REPRESENTATION</a></li>
22	<li><a href="#TIME_AND_OTHER_GLOBAL_FUNCTIONS">TIME AND OTHER GLOBAL FUNCTIONS</a></li>	23	<li><a href="#GLOBAL_FUNCTIONS">GLOBAL FUNCTIONS</a></li>
23	<li><a href="#FUNCTIONS_CONTROLLING_THE_EVENT_LOOP">FUNCTIONS CONTROLLING THE EVENT LOOP</a></li>	24	<li><a href="#FUNCTIONS_CONTROLLING_THE_EVENT_LOOP">FUNCTIONS CONTROLLING THE EVENT LOOP</a></li>
24	<li><a href="#ANATOMY_OF_A_WATCHER">ANATOMY OF A WATCHER</a>	25	<li><a href="#ANATOMY_OF_A_WATCHER">ANATOMY OF A WATCHER</a>
		26	<ul><li><a href="#SUMMARY_OF_GENERIC_WATCHER_FUNCTIONS">SUMMARY OF GENERIC WATCHER FUNCTIONS</a></li>
25	<ul><li><a href="#ASSOCIATING_CUSTOM_DATA_WITH_A_WATCH">ASSOCIATING CUSTOM DATA WITH A WATCHER</a></li>	27	<li><a href="#ASSOCIATING_CUSTOM_DATA_WITH_A_WATCH">ASSOCIATING CUSTOM DATA WITH A WATCHER</a></li>
26	</ul>	28	</ul>
27	</li>	29	</li>
28	<li><a href="#WATCHER_TYPES">WATCHER TYPES</a>	30	<li><a href="#WATCHER_TYPES">WATCHER TYPES</a>
29	<ul><li><a href="#struct_ev_io_is_my_file_descriptor_r">struct ev_io - is my file descriptor readable or writable</a></li>	31	<ul><li><a href="#code_ev_io_code_is_this_file_descrip"><code>ev_io</code> - is this file descriptor readable or writable</a></li>
30	<li><a href="#struct_ev_timer_relative_and_optiona">struct ev_timer - relative and optionally recurring timeouts</a></li>	32	<li><a href="#code_ev_timer_code_relative_and_opti"><code>ev_timer</code> - relative and optionally recurring timeouts</a></li>
31	<li><a href="#ev_periodic">ev_periodic</a></li>	33	<li><a href="#code_ev_periodic_code_to_cron_or_not"><code>ev_periodic</code> - to cron or not to cron</a></li>
32	<li><a href="#ev_signal_signal_me_when_a_signal_ge">ev_signal - signal me when a signal gets signalled</a></li>	34	<li><a href="#code_ev_signal_code_signal_me_when_a"><code>ev_signal</code> - signal me when a signal gets signalled</a></li>
33	<li><a href="#ev_child_wait_for_pid_status_changes">ev_child - wait for pid status changes</a></li>	35	<li><a href="#code_ev_child_code_wait_for_pid_stat"><code>ev_child</code> - wait for pid status changes</a></li>
34	<li><a href="#ev_idle_when_you_ve_got_nothing_bett">ev_idle - when you've got nothing better to do</a></li>	36	<li><a href="#code_ev_idle_code_when_you_ve_got_no"><code>ev_idle</code> - when you've got nothing better to do</a></li>
35	<li><a href="#prepare_and_check_your_hooks_into_th">prepare and check - your hooks into the event loop</a></li>	37	<li><a href="#code_ev_prepare_code_and_code_ev_che"><code>ev_prepare</code> and <code>ev_check</code> - customise your event loop</a></li>
		38	<li><a href="#code_ev_embed_code_when_one_backend_"><code>ev_embed</code> - when one backend isn't enough</a></li>
36	</ul>	39	</ul>
37	</li>	40	</li>
38	<li><a href="#OTHER_FUNCTIONS">OTHER FUNCTIONS</a></li>	41	<li><a href="#OTHER_FUNCTIONS">OTHER FUNCTIONS</a></li>
		42	<li><a href="#LIBEVENT_EMULATION">LIBEVENT EMULATION</a></li>
		43	<li><a href="#C_SUPPORT">C++ SUPPORT</a></li>
39	<li><a href="#AUTHOR">AUTHOR</a>	44	<li><a href="#AUTHOR">AUTHOR</a>
40	</li>	45	</li>
41	</ul><hr />	46	</ul><hr />
42	<!-- INDEX END -->	47	<!-- INDEX END -->
43		48
…		…
55	</div>	60	</div>
56	<h1 id="DESCRIPTION">DESCRIPTION</h1><p><a href="#TOP" class="toplink">Top</a></p>	61	<h1 id="DESCRIPTION">DESCRIPTION</h1><p><a href="#TOP" class="toplink">Top</a></p>
57	<div id="DESCRIPTION_CONTENT">	62	<div id="DESCRIPTION_CONTENT">
58	<p>Libev is an event loop: you register interest in certain events (such as a	63	<p>Libev is an event loop: you register interest in certain events (such as a
59	file descriptor being readable or a timeout occuring), and it will manage	64	file descriptor being readable or a timeout occuring), and it will manage
60	these event sources and provide your program events.</p>	65	these event sources and provide your program with events.</p>
61	<p>To do this, it must take more or less complete control over your process	66	<p>To do this, it must take more or less complete control over your process
62	(or thread) by executing the <i>event loop</i> handler, and will then	67	(or thread) by executing the <i>event loop</i> handler, and will then
63	communicate events via a callback mechanism.</p>	68	communicate events via a callback mechanism.</p>
64	<p>You register interest in certain events by registering so-called <i>event	69	<p>You register interest in certain events by registering so-called <i>event
65	watchers</i>, which are relatively small C structures you initialise with the	70	watchers</i>, which are relatively small C structures you initialise with the
…		…
71	<div id="FEATURES_CONTENT">	76	<div id="FEATURES_CONTENT">
72	<p>Libev supports select, poll, the linux-specific epoll and the bsd-specific	77	<p>Libev supports select, poll, the linux-specific epoll and the bsd-specific
73	kqueue mechanisms for file descriptor events, relative timers, absolute	78	kqueue mechanisms for file descriptor events, relative timers, absolute
74	timers with customised rescheduling, signal events, process status change	79	timers with customised rescheduling, signal events, process status change
75	events (related to SIGCHLD), and event watchers dealing with the event	80	events (related to SIGCHLD), and event watchers dealing with the event
76	loop mechanism itself (idle, prepare and check watchers).</p>	81	loop mechanism itself (idle, prepare and check watchers). It also is quite
		82	fast (see this <a href="http://libev.schmorp.de/bench.html">benchmark</a> comparing
		83	it to libevent for example).</p>
77		84
78	</div>	85	</div>
79	<h1 id="CONVENTIONS">CONVENTIONS</h1><p><a href="#TOP" class="toplink">Top</a></p>	86	<h1 id="CONVENTIONS">CONVENTIONS</h1><p><a href="#TOP" class="toplink">Top</a></p>
80	<div id="CONVENTIONS_CONTENT">	87	<div id="CONVENTIONS_CONTENT">
81	<p>Libev is very configurable. In this manual the default configuration	88	<p>Libev is very configurable. In this manual the default configuration
82	will be described, which supports multiple event loops. For more info	89	will be described, which supports multiple event loops. For more info
83	about various configuraiton options please have a look at the file	90	about various configuration options please have a look at the file
84	<cite>README.embed</cite> in the libev distribution. If libev was configured without	91	<cite>README.embed</cite> in the libev distribution. If libev was configured without
85	support for multiple event loops, then all functions taking an initial	92	support for multiple event loops, then all functions taking an initial
86	argument of name <code>loop</code> (which is always of type <code>struct ev_loop *</code>)	93	argument of name <code>loop</code> (which is always of type <code>struct ev_loop *</code>)
87	will not have this argument.</p>	94	will not have this argument.</p>
88		95
89	</div>	96	</div>
90	<h1 id="TIME_AND_OTHER_GLOBAL_FUNCTIONS">TIME AND OTHER GLOBAL FUNCTIONS</h1><p><a href="#TOP" class="toplink">Top</a></p>	97	<h1 id="TIME_REPRESENTATION">TIME REPRESENTATION</h1><p><a href="#TOP" class="toplink">Top</a></p>
91	<div id="TIME_AND_OTHER_GLOBAL_FUNCTIONS_CONT">	98	<div id="TIME_REPRESENTATION_CONTENT">
92	<p>Libev represents time as a single floating point number, representing the	99	<p>Libev represents time as a single floating point number, representing the
93	(fractional) number of seconds since the (POSIX) epoch (somewhere near	100	(fractional) number of seconds since the (POSIX) epoch (somewhere near
94	the beginning of 1970, details are complicated, don't ask). This type is	101	the beginning of 1970, details are complicated, don't ask). This type is
95	called <code>ev_tstamp</code>, which is what you should use too. It usually aliases	102	called <code>ev_tstamp</code>, which is what you should use too. It usually aliases
96	to the double type in C.</p>	103	to the <code>double</code> type in C, and when you need to do any calculations on
		104	it, you should treat it as such.</p>
		105
		106
		107
		108
		109
		110	</div>
		111	<h1 id="GLOBAL_FUNCTIONS">GLOBAL FUNCTIONS</h1><p><a href="#TOP" class="toplink">Top</a></p>
		112	<div id="GLOBAL_FUNCTIONS_CONTENT">
		113	<p>These functions can be called anytime, even before initialising the
		114	library in any way.</p>
97	<dl>	115	<dl>
98	<dt>ev_tstamp ev_time ()</dt>	116	<dt>ev_tstamp ev_time ()</dt>
99	<dd>	117	<dd>
100	<p>Returns the current time as libev would use it.</p>	118	<p>Returns the current time as libev would use it. Please note that the
		119	<code>ev_now</code> function is usually faster and also often returns the timestamp
		120	you actually want to know.</p>
101	</dd>	121	</dd>
102	<dt>int ev_version_major ()</dt>	122	<dt>int ev_version_major ()</dt>
103	<dt>int ev_version_minor ()</dt>	123	<dt>int ev_version_minor ()</dt>
104	<dd>	124	<dd>
105	<p>You can find out the major and minor version numbers of the library	125	<p>You can find out the major and minor version numbers of the library
106	you linked against by calling the functions <code>ev_version_major</code> and	126	you linked against by calling the functions <code>ev_version_major</code> and
107	<code>ev_version_minor</code>. If you want, you can compare against the global	127	<code>ev_version_minor</code>. If you want, you can compare against the global
108	symbols <code>EV_VERSION_MAJOR</code> and <code>EV_VERSION_MINOR</code>, which specify the	128	symbols <code>EV_VERSION_MAJOR</code> and <code>EV_VERSION_MINOR</code>, which specify the
109	version of the library your program was compiled against.</p>	129	version of the library your program was compiled against.</p>
110	<p>Usually, its a good idea to terminate if the major versions mismatch,	130	<p>Usually, it's a good idea to terminate if the major versions mismatch,
111	as this indicates an incompatible change. Minor versions are usually	131	as this indicates an incompatible change. Minor versions are usually
112	compatible to older versions, so a larger minor version alone is usually	132	compatible to older versions, so a larger minor version alone is usually
113	not a problem.</p>	133	not a problem.</p>
		134	<p>Example: make sure we haven't accidentally been linked against the wrong
		135	version:</p>
		136	<pre> assert (("libev version mismatch",
		137	ev_version_major () == EV_VERSION_MAJOR
		138	&& ev_version_minor () >= EV_VERSION_MINOR));
		139
		140	</pre>
		141	</dd>
		142	<dt>unsigned int ev_supported_backends ()</dt>
		143	<dd>
		144	<p>Return the set of all backends (i.e. their corresponding <code>EV_BACKEND_*</code>
		145	value) compiled into this binary of libev (independent of their
		146	availability on the system you are running on). See <code>ev_default_loop</code> for
		147	a description of the set values.</p>
		148	<p>Example: make sure we have the epoll method, because yeah this is cool and
		149	a must have and can we have a torrent of it please!!!11</p>
		150	<pre> assert (("sorry, no epoll, no sex",
		151	ev_supported_backends () & EVBACKEND_EPOLL));
		152
		153	</pre>
		154	</dd>
		155	<dt>unsigned int ev_recommended_backends ()</dt>
		156	<dd>
		157	<p>Return the set of all backends compiled into this binary of libev and also
		158	recommended for this platform. This set is often smaller than the one
		159	returned by <code>ev_supported_backends</code>, as for example kqueue is broken on
		160	most BSDs and will not be autodetected unless you explicitly request it
		161	(assuming you know what you are doing). This is the set of backends that
		162	libev will probe for if you specify no backends explicitly.</p>
		163	</dd>
		164	<dt>unsigned int ev_embeddable_backends ()</dt>
		165	<dd>
		166	<p>Returns the set of backends that are embeddable in other event loops. This
		167	is the theoretical, all-platform, value. To find which backends
		168	might be supported on the current system, you would need to look at
		169	<code>ev_embeddable_backends () & ev_supported_backends ()</code>, likewise for
		170	recommended ones.</p>
		171	<p>See the description of <code>ev_embed</code> watchers for more info.</p>
114	</dd>	172	</dd>
115	<dt>ev_set_allocator (void (cb)(void *ptr, long size))</dt>	173	<dt>ev_set_allocator (void (cb)(void *ptr, long size))</dt>
116	<dd>	174	<dd>
117	<p>Sets the allocation function to use (the prototype is similar to the	175	<p>Sets the allocation function to use (the prototype is similar to the
118	realloc function). It is used to allocate and free memory (no surprises	176	realloc C function, the semantics are identical). It is used to allocate
119	here). If it returns zero when memory needs to be allocated, the library	177	and free memory (no surprises here). If it returns zero when memory
120	might abort or take some potentially destructive action. The default is	178	needs to be allocated, the library might abort or take some potentially
121	your system realloc function.</p>	179	destructive action. The default is your system realloc function.</p>
122	<p>You could override this function in high-availability programs to, say,	180	<p>You could override this function in high-availability programs to, say,
123	free some memory if it cannot allocate memory, to use a special allocator,	181	free some memory if it cannot allocate memory, to use a special allocator,
124	or even to sleep a while and retry until some memory is available.</p>	182	or even to sleep a while and retry until some memory is available.</p>
		183	<p>Example: replace the libev allocator with one that waits a bit and then
		184	retries: better than mine).</p>
		185	<pre> static void *
		186	persistent_realloc (void *ptr, long size)
		187	{
		188	for (;;)
		189	{
		190	void *newptr = realloc (ptr, size);
		191
		192	if (newptr)
		193	return newptr;
		194
		195	sleep (60);
		196	}
		197	}
		198
		199	...
		200	ev_set_allocator (persistent_realloc);
		201
		202	</pre>
125	</dd>	203	</dd>
126	<dt>ev_set_syserr_cb (void (cb)(const char msg));</dt>	204	<dt>ev_set_syserr_cb (void (cb)(const char msg));</dt>
127	<dd>	205	<dd>
128	<p>Set the callback function to call on a retryable syscall error (such	206	<p>Set the callback function to call on a retryable syscall error (such
129	as failed select, poll, epoll_wait). The message is a printable string	207	as failed select, poll, epoll_wait). The message is a printable string
130	indicating the system call or subsystem causing the problem. If this	208	indicating the system call or subsystem causing the problem. If this
131	callback is set, then libev will expect it to remedy the sitution, no	209	callback is set, then libev will expect it to remedy the sitution, no
132	matter what, when it returns. That is, libev will geenrally retry the	210	matter what, when it returns. That is, libev will generally retry the
133	requested operation, or, if the condition doesn't go away, do bad stuff	211	requested operation, or, if the condition doesn't go away, do bad stuff
134	(such as abort).</p>	212	(such as abort).</p>
		213	<p>Example: do the same thing as libev does internally:</p>
		214	<pre> static void
		215	fatal_error (const char *msg)
		216	{
		217	perror (msg);
		218	abort ();
		219	}
		220
		221	...
		222	ev_set_syserr_cb (fatal_error);
		223
		224	</pre>
135	</dd>	225	</dd>
136	</dl>	226	</dl>
137		227
138	</div>	228	</div>
139	<h1 id="FUNCTIONS_CONTROLLING_THE_EVENT_LOOP">FUNCTIONS CONTROLLING THE EVENT LOOP</h1><p><a href="#TOP" class="toplink">Top</a></p>	229	<h1 id="FUNCTIONS_CONTROLLING_THE_EVENT_LOOP">FUNCTIONS CONTROLLING THE EVENT LOOP</h1><p><a href="#TOP" class="toplink">Top</a></p>
140	<div id="FUNCTIONS_CONTROLLING_THE_EVENT_LOOP-2">	230	<div id="FUNCTIONS_CONTROLLING_THE_EVENT_LOOP-2">
141	<p>An event loop is described by a <code>struct ev_loop *</code>. The library knows two	231	<p>An event loop is described by a <code>struct ev_loop *</code>. The library knows two
142	types of such loops, the <i>default</i> loop, which supports signals and child	232	types of such loops, the <i>default</i> loop, which supports signals and child
143	events, and dynamically created loops which do not.</p>	233	events, and dynamically created loops which do not.</p>
144	<p>If you use threads, a common model is to run the default event loop	234	<p>If you use threads, a common model is to run the default event loop
145	in your main thread (or in a separate thrad) and for each thread you	235	in your main thread (or in a separate thread) and for each thread you
146	create, you also create another event loop. Libev itself does no lockign	236	create, you also create another event loop. Libev itself does no locking
147	whatsoever, so if you mix calls to different event loops, make sure you	237	whatsoever, so if you mix calls to the same event loop in different
148	lock (this is usually a bad idea, though, even if done right).</p>	238	threads, make sure you lock (this is usually a bad idea, though, even if
		239	done correctly, because it's hideous and inefficient).</p>
149	<dl>	240	<dl>
150	<dt>struct ev_loop *ev_default_loop (unsigned int flags)</dt>	241	<dt>struct ev_loop *ev_default_loop (unsigned int flags)</dt>
151	<dd>	242	<dd>
152	<p>This will initialise the default event loop if it hasn't been initialised	243	<p>This will initialise the default event loop if it hasn't been initialised
153	yet and return it. If the default loop could not be initialised, returns	244	yet and return it. If the default loop could not be initialised, returns
154	false. If it already was initialised it simply returns it (and ignores the	245	false. If it already was initialised it simply returns it (and ignores the
155	flags).</p>	246	flags. If that is troubling you, check <code>ev_backend ()</code> afterwards).</p>
156	<p>If you don't know what event loop to use, use the one returned from this	247	<p>If you don't know what event loop to use, use the one returned from this
157	function.</p>	248	function.</p>
158	<p>The flags argument can be used to specify special behaviour or specific	249	<p>The flags argument can be used to specify special behaviour or specific
159	backends to use, and is usually specified as 0 (or EVFLAG_AUTO)</p>	250	backends to use, and is usually specified as <code>0</code> (or <code>EVFLAG_AUTO</code>).</p>
160	<p>It supports the following flags:</p>	251	<p>The following flags are supported:</p>
161	<p>	252	<p>
162	<dl>	253	<dl>
163	<dt>EVFLAG_AUTO</dt>	254	<dt><code>EVFLAG_AUTO</code></dt>
164	<dd>	255	<dd>
165	<p>The default flags value. Use this if you have no clue (its the right	256	<p>The default flags value. Use this if you have no clue (it's the right
166	thing, believe me).</p>	257	thing, believe me).</p>
167	</dd>	258	</dd>
168	<dt>EVFLAG_NOENV</dt>	259	<dt><code>EVFLAG_NOENV</code></dt>
169	<dd>
170	<p>If this flag bit is ored into the flag value then libev will <i>not</i> look
171	at the environment variable <code>LIBEV_FLAGS</code>. Otherwise (the default), this
172	environment variable will override the flags completely. This is useful
173	to try out specific backends to tets their performance, or to work around
174	bugs.</p>
175	</dd>	260	<dd>
176	<dt>EVMETHOD_SELECT portable select backend</dt>	261	<p>If this flag bit is ored into the flag value (or the program runs setuid
177	<dt>EVMETHOD_POLL poll backend (everywhere except windows)</dt>	262	or setgid) then libev will <i>not</i> look at the environment variable
178	<dt>EVMETHOD_EPOLL linux only</dt>	263	<code>LIBEV_FLAGS</code>. Otherwise (the default), this environment variable will
179	<dt>EVMETHOD_KQUEUE some bsds only</dt>	264	override the flags completely if it is found in the environment. This is
180	<dt>EVMETHOD_DEVPOLL solaris 8 only</dt>	265	useful to try out specific backends to test their performance, or to work
181	<dt>EVMETHOD_PORT solaris 10 only</dt>	266	around bugs.</p>
182	<dd>	267	</dd>
183	<p>If one or more of these are ored into the flags value, then only these	268	<dt><code>EVBACKEND_SELECT</code> (value 1, portable select backend)</dt>
184	backends will be tried (in the reverse order as given here). If one are	269	<dd>
185	specified, any backend will do.</p>	270	<p>This is your standard select(2) backend. Not <i>completely</i> standard, as
		271	libev tries to roll its own fd_set with no limits on the number of fds,
		272	but if that fails, expect a fairly low limit on the number of fds when
		273	using this backend. It doesn't scale too well (O(highest_fd)), but its usually
		274	the fastest backend for a low number of fds.</p>
		275	</dd>
		276	<dt><code>EVBACKEND_POLL</code> (value 2, poll backend, available everywhere except on windows)</dt>
		277	<dd>
		278	<p>And this is your standard poll(2) backend. It's more complicated than
		279	select, but handles sparse fds better and has no artificial limit on the
		280	number of fds you can use (except it will slow down considerably with a
		281	lot of inactive fds). It scales similarly to select, i.e. O(total_fds).</p>
		282	</dd>
		283	<dt><code>EVBACKEND_EPOLL</code> (value 4, Linux)</dt>
		284	<dd>
		285	<p>For few fds, this backend is a bit little slower than poll and select,
		286	but it scales phenomenally better. While poll and select usually scale like
		287	O(total_fds) where n is the total number of fds (or the highest fd), epoll scales
		288	either O(1) or O(active_fds).</p>
		289	<p>While stopping and starting an I/O watcher in the same iteration will
		290	result in some caching, there is still a syscall per such incident
		291	(because the fd could point to a different file description now), so its
		292	best to avoid that. Also, dup()ed file descriptors might not work very
		293	well if you register events for both fds.</p>
		294	<p>Please note that epoll sometimes generates spurious notifications, so you
		295	need to use non-blocking I/O or other means to avoid blocking when no data
		296	(or space) is available.</p>
		297	</dd>
		298	<dt><code>EVBACKEND_KQUEUE</code> (value 8, most BSD clones)</dt>
		299	<dd>
		300	<p>Kqueue deserves special mention, as at the time of this writing, it
		301	was broken on all BSDs except NetBSD (usually it doesn't work with
		302	anything but sockets and pipes, except on Darwin, where of course its
		303	completely useless). For this reason its not being "autodetected"
		304	unless you explicitly specify it explicitly in the flags (i.e. using
		305	<code>EVBACKEND_KQUEUE</code>).</p>
		306	<p>It scales in the same way as the epoll backend, but the interface to the
		307	kernel is more efficient (which says nothing about its actual speed, of
		308	course). While starting and stopping an I/O watcher does not cause an
		309	extra syscall as with epoll, it still adds up to four event changes per
		310	incident, so its best to avoid that.</p>
		311	</dd>
		312	<dt><code>EVBACKEND_DEVPOLL</code> (value 16, Solaris 8)</dt>
		313	<dd>
		314	<p>This is not implemented yet (and might never be).</p>
		315	</dd>
		316	<dt><code>EVBACKEND_PORT</code> (value 32, Solaris 10)</dt>
		317	<dd>
		318	<p>This uses the Solaris 10 port mechanism. As with everything on Solaris,
		319	it's really slow, but it still scales very well (O(active_fds)).</p>
		320	<p>Please note that solaris ports can result in a lot of spurious
		321	notifications, so you need to use non-blocking I/O or other means to avoid
		322	blocking when no data (or space) is available.</p>
		323	</dd>
		324	<dt><code>EVBACKEND_ALL</code></dt>
		325	<dd>
		326	<p>Try all backends (even potentially broken ones that wouldn't be tried
		327	with <code>EVFLAG_AUTO</code>). Since this is a mask, you can do stuff such as
		328	<code>EVBACKEND_ALL & ~EVBACKEND_KQUEUE</code>.</p>
186	</dd>	329	</dd>
187	</dl>	330	</dl>
188	</p>	331	</p>
		332	<p>If one or more of these are ored into the flags value, then only these
		333	backends will be tried (in the reverse order as given here). If none are
		334	specified, most compiled-in backend will be tried, usually in reverse
		335	order of their flag values :)</p>
		336	<p>The most typical usage is like this:</p>
		337	<pre> if (!ev_default_loop (0))
		338	fatal ("could not initialise libev, bad $LIBEV_FLAGS in environment?");
		339
		340	</pre>
		341	<p>Restrict libev to the select and poll backends, and do not allow
		342	environment settings to be taken into account:</p>
		343	<pre> ev_default_loop (EVBACKEND_POLL \| EVBACKEND_SELECT \| EVFLAG_NOENV);
		344
		345	</pre>
		346	<p>Use whatever libev has to offer, but make sure that kqueue is used if
		347	available (warning, breaks stuff, best use only with your own private
		348	event loop and only if you know the OS supports your types of fds):</p>
		349	<pre> ev_default_loop (ev_recommended_backends () \| EVBACKEND_KQUEUE);
		350
		351	</pre>
189	</dd>	352	</dd>
190	<dt>struct ev_loop *ev_loop_new (unsigned int flags)</dt>	353	<dt>struct ev_loop *ev_loop_new (unsigned int flags)</dt>
191	<dd>	354	<dd>
192	<p>Similar to <code>ev_default_loop</code>, but always creates a new event loop that is	355	<p>Similar to <code>ev_default_loop</code>, but always creates a new event loop that is
193	always distinct from the default loop. Unlike the default loop, it cannot	356	always distinct from the default loop. Unlike the default loop, it cannot
194	handle signal and child watchers, and attempts to do so will be greeted by	357	handle signal and child watchers, and attempts to do so will be greeted by
195	undefined behaviour (or a failed assertion if assertions are enabled).</p>	358	undefined behaviour (or a failed assertion if assertions are enabled).</p>
		359	<p>Example: try to create a event loop that uses epoll and nothing else.</p>
		360	<pre> struct ev_loop *epoller = ev_loop_new (EVBACKEND_EPOLL \| EVFLAG_NOENV);
		361	if (!epoller)
		362	fatal ("no epoll found here, maybe it hides under your chair");
		363
		364	</pre>
196	</dd>	365	</dd>
197	<dt>ev_default_destroy ()</dt>	366	<dt>ev_default_destroy ()</dt>
198	<dd>	367	<dd>
199	<p>Destroys the default loop again (frees all memory and kernel state	368	<p>Destroys the default loop again (frees all memory and kernel state
200	etc.). This stops all registered event watchers (by not touching them in	369	etc.). None of the active event watchers will be stopped in the normal
201	any way whatsoever, although you cnanot rely on this :).</p>	370	sense, so e.g. <code>ev_is_active</code> might still return true. It is your
		371	responsibility to either stop all watchers cleanly yoursef <i>before</i>
		372	calling this function, or cope with the fact afterwards (which is usually
		373	the easiest thing, youc na just ignore the watchers and/or <code>free ()</code> them
		374	for example).</p>
202	</dd>	375	</dd>
203	<dt>ev_loop_destroy (loop)</dt>	376	<dt>ev_loop_destroy (loop)</dt>
204	<dd>	377	<dd>
205	<p>Like <code>ev_default_destroy</code>, but destroys an event loop created by an	378	<p>Like <code>ev_default_destroy</code>, but destroys an event loop created by an
206	earlier call to <code>ev_loop_new</code>.</p>	379	earlier call to <code>ev_loop_new</code>.</p>
…		…
209	<dd>	382	<dd>
210	<p>This function reinitialises the kernel state for backends that have	383	<p>This function reinitialises the kernel state for backends that have
211	one. Despite the name, you can call it anytime, but it makes most sense	384	one. Despite the name, you can call it anytime, but it makes most sense
212	after forking, in either the parent or child process (or both, but that	385	after forking, in either the parent or child process (or both, but that
213	again makes little sense).</p>	386	again makes little sense).</p>
214	<p>You <i>must</i> call this function after forking if and only if you want to	387	<p>You <i>must</i> call this function in the child process after forking if and
215	use the event library in both processes. If you just fork+exec, you don't	388	only if you want to use the event library in both processes. If you just
216	have to call it.</p>	389	fork+exec, you don't have to call it.</p>
217	<p>The function itself is quite fast and its usually not a problem to call	390	<p>The function itself is quite fast and it's usually not a problem to call
218	it just in case after a fork. To make this easy, the function will fit in	391	it just in case after a fork. To make this easy, the function will fit in
219	quite nicely into a call to <code>pthread_atfork</code>:</p>	392	quite nicely into a call to <code>pthread_atfork</code>:</p>
220	<pre> pthread_atfork (0, 0, ev_default_fork);	393	<pre> pthread_atfork (0, 0, ev_default_fork);
221		394
222	</pre>	395	</pre>
		396	<p>At the moment, <code>EVBACKEND_SELECT</code> and <code>EVBACKEND_POLL</code> are safe to use
		397	without calling this function, so if you force one of those backends you
		398	do not need to care.</p>
223	</dd>	399	</dd>
224	<dt>ev_loop_fork (loop)</dt>	400	<dt>ev_loop_fork (loop)</dt>
225	<dd>	401	<dd>
226	<p>Like <code>ev_default_fork</code>, but acts on an event loop created by	402	<p>Like <code>ev_default_fork</code>, but acts on an event loop created by
227	<code>ev_loop_new</code>. Yes, you have to call this on every allocated event loop	403	<code>ev_loop_new</code>. Yes, you have to call this on every allocated event loop
228	after fork, and how you do this is entirely your own problem.</p>	404	after fork, and how you do this is entirely your own problem.</p>
229	</dd>	405	</dd>
230	<dt>unsigned int ev_method (loop)</dt>	406	<dt>unsigned int ev_backend (loop)</dt>
231	<dd>	407	<dd>
232	<p>Returns one of the <code>EVMETHOD_*</code> flags indicating the event backend in	408	<p>Returns one of the <code>EVBACKEND_*</code> flags indicating the event backend in
233	use.</p>	409	use.</p>
234	</dd>	410	</dd>
235	<dt>ev_tstamp = ev_now (loop)</dt>	411	<dt>ev_tstamp ev_now (loop)</dt>
236	<dd>	412	<dd>
237	<p>Returns the current "event loop time", which is the time the event loop	413	<p>Returns the current "event loop time", which is the time the event loop
238	got events and started processing them. This timestamp does not change	414	received events and started processing them. This timestamp does not
239	as long as callbacks are being processed, and this is also the base time	415	change as long as callbacks are being processed, and this is also the base
240	used for relative timers. You can treat it as the timestamp of the event	416	time used for relative timers. You can treat it as the timestamp of the
241	occuring (or more correctly, the mainloop finding out about it).</p>	417	event occuring (or more correctly, libev finding out about it).</p>
242	</dd>	418	</dd>
243	<dt>ev_loop (loop, int flags)</dt>	419	<dt>ev_loop (loop, int flags)</dt>
244	<dd>	420	<dd>
245	<p>Finally, this is it, the event handler. This function usually is called	421	<p>Finally, this is it, the event handler. This function usually is called
246	after you initialised all your watchers and you want to start handling	422	after you initialised all your watchers and you want to start handling
247	events.</p>	423	events.</p>
248	<p>If the flags argument is specified as 0, it will not return until either	424	<p>If the flags argument is specified as <code>0</code>, it will not return until
249	no event watchers are active anymore or <code>ev_unloop</code> was called.</p>	425	either no event watchers are active anymore or <code>ev_unloop</code> was called.</p>
		426	<p>Please note that an explicit <code>ev_unloop</code> is usually better than
		427	relying on all watchers to be stopped when deciding when a program has
		428	finished (especially in interactive programs), but having a program that
		429	automatically loops as long as it has to and no longer by virtue of
		430	relying on its watchers stopping correctly is a thing of beauty.</p>
250	<p>A flags value of <code>EVLOOP_NONBLOCK</code> will look for new events, will handle	431	<p>A flags value of <code>EVLOOP_NONBLOCK</code> will look for new events, will handle
251	those events and any outstanding ones, but will not block your process in	432	those events and any outstanding ones, but will not block your process in
252	case there are no events.</p>	433	case there are no events and will return after one iteration of the loop.</p>
253	<p>A flags value of <code>EVLOOP_ONESHOT</code> will look for new events (waiting if	434	<p>A flags value of <code>EVLOOP_ONESHOT</code> will look for new events (waiting if
254	neccessary) and will handle those and any outstanding ones. It will block	435	neccessary) and will handle those and any outstanding ones. It will block
255	your process until at least one new event arrives.</p>	436	your process until at least one new event arrives, and will return after
256	<p>This flags value could be used to implement alternative looping	437	one iteration of the loop. This is useful if you are waiting for some
257	constructs, but the <code>prepare</code> and <code>check</code> watchers provide a better and	438	external event in conjunction with something not expressible using other
258	more generic mechanism.</p>	439	libev watchers. However, a pair of <code>ev_prepare</code>/<code>ev_check</code> watchers is
		440	usually a better approach for this kind of thing.</p>
		441	<p>Here are the gory details of what <code>ev_loop</code> does:</p>
		442	<pre> * If there are no active watchers (reference count is zero), return.
		443	- Queue prepare watchers and then call all outstanding watchers.
		444	- If we have been forked, recreate the kernel state.
		445	- Update the kernel state with all outstanding changes.
		446	- Update the "event loop time".
		447	- Calculate for how long to block.
		448	- Block the process, waiting for any events.
		449	- Queue all outstanding I/O (fd) events.
		450	- Update the "event loop time" and do time jump handling.
		451	- Queue all outstanding timers.
		452	- Queue all outstanding periodics.
		453	- If no events are pending now, queue all idle watchers.
		454	- Queue all check watchers.
		455	- Call all queued watchers in reverse order (i.e. check watchers first).
		456	Signals and child watchers are implemented as I/O watchers, and will
		457	be handled here by queueing them when their watcher gets executed.
		458	- If ev_unloop has been called or EVLOOP_ONESHOT or EVLOOP_NONBLOCK
		459	were used, return, otherwise continue with step *.
		460
		461	</pre>
		462	<p>Example: queue some jobs and then loop until no events are outsanding
		463	anymore.</p>
		464	<pre> ... queue jobs here, make sure they register event watchers as long
		465	... as they still have work to do (even an idle watcher will do..)
		466	ev_loop (my_loop, 0);
		467	... jobs done. yeah!
		468
		469	</pre>
259	</dd>	470	</dd>
260	<dt>ev_unloop (loop, how)</dt>	471	<dt>ev_unloop (loop, how)</dt>
261	<dd>	472	<dd>
262	<p>Can be used to make a call to <code>ev_loop</code> return early. The <code>how</code> argument	473	<p>Can be used to make a call to <code>ev_loop</code> return early (but only after it
		474	has processed all outstanding events). The <code>how</code> argument must be either
263	must be either <code>EVUNLOOP_ONCE</code>, which will make the innermost <code>ev_loop</code>	475	<code>EVUNLOOP_ONE</code>, which will make the innermost <code>ev_loop</code> call return, or
264	call return, or <code>EVUNLOOP_ALL</code>, which will make all nested <code>ev_loop</code>	476	<code>EVUNLOOP_ALL</code>, which will make all nested <code>ev_loop</code> calls return.</p>
265	calls return.</p>
266	</dd>	477	</dd>
267	<dt>ev_ref (loop)</dt>	478	<dt>ev_ref (loop)</dt>
268	<dt>ev_unref (loop)</dt>	479	<dt>ev_unref (loop)</dt>
269	<dd>	480	<dd>
270	<p>Ref/unref can be used to add or remove a refcount on the event loop: Every	481	<p>Ref/unref can be used to add or remove a reference count on the event
271	watcher keeps one reference. If you have a long-runing watcher you never	482	loop: Every watcher keeps one reference, and as long as the reference
272	unregister that should not keep ev_loop from running, ev_unref() after	483	count is nonzero, <code>ev_loop</code> will not return on its own. If you have
273	starting, and ev_ref() before stopping it. Libev itself uses this for	484	a watcher you never unregister that should not keep <code>ev_loop</code> from
274	example for its internal signal pipe: It is not visible to you as a user	485	returning, ev_unref() after starting, and ev_ref() before stopping it. For
275	and should not keep <code>ev_loop</code> from exiting if the work is done. It is	486	example, libev itself uses this for its internal signal pipe: It is not
276	also an excellent way to do this for generic recurring timers or from	487	visible to the libev user and should not keep <code>ev_loop</code> from exiting if
277	within third-party libraries. Just remember to unref after start and ref	488	no event watchers registered by it are active. It is also an excellent
278	before stop.</p>	489	way to do this for generic recurring timers or from within third-party
		490	libraries. Just remember to <i>unref after start</i> and <i>ref before stop</i>.</p>
		491	<p>Example: create a signal watcher, but keep it from keeping <code>ev_loop</code>
		492	running when nothing else is active.</p>
		493	<pre> struct dv_signal exitsig;
		494	ev_signal_init (&exitsig, sig_cb, SIGINT);
		495	ev_signal_start (myloop, &exitsig);
		496	evf_unref (myloop);
		497
		498	</pre>
		499	<p>Example: for some weird reason, unregister the above signal handler again.</p>
		500	<pre> ev_ref (myloop);
		501	ev_signal_stop (myloop, &exitsig);
		502
		503	</pre>
279	</dd>	504	</dd>
280	</dl>	505	</dl>
281		506
282	</div>	507	</div>
283	<h1 id="ANATOMY_OF_A_WATCHER">ANATOMY OF A WATCHER</h1><p><a href="#TOP" class="toplink">Top</a></p>	508	<h1 id="ANATOMY_OF_A_WATCHER">ANATOMY OF A WATCHER</h1><p><a href="#TOP" class="toplink">Top</a></p>
284	<div id="ANATOMY_OF_A_WATCHER_CONTENT">	509	<div id="ANATOMY_OF_A_WATCHER_CONTENT">
285	<p>A watcher is a structure that you create and register to record your	510	<p>A watcher is a structure that you create and register to record your
286	interest in some event. For instance, if you want to wait for STDIN to	511	interest in some event. For instance, if you want to wait for STDIN to
287	become readable, you would create an ev_io watcher for that:</p>	512	become readable, you would create an <code>ev_io</code> watcher for that:</p>
288	<pre> static void my_cb (struct ev_loop loop, struct ev_io w, int revents)	513	<pre> static void my_cb (struct ev_loop loop, struct ev_io w, int revents)
289	{	514	{
290	ev_io_stop (w);	515	ev_io_stop (w);
291	ev_unloop (loop, EVUNLOOP_ALL);	516	ev_unloop (loop, EVUNLOOP_ALL);
292	}	517	}
…		…
315	with a watcher-specific start function (<code>ev_<type>_start (loop, watcher	540	with a watcher-specific start function (<code>ev_<type>_start (loop, watcher
316	*)</code>), and you can stop watching for events at any time by calling the	541	*)</code>), and you can stop watching for events at any time by calling the
317	corresponding stop function (<code>ev_<type>_stop (loop, watcher *)</code>.</p>	542	corresponding stop function (<code>ev_<type>_stop (loop, watcher *)</code>.</p>
318	<p>As long as your watcher is active (has been started but not stopped) you	543	<p>As long as your watcher is active (has been started but not stopped) you
319	must not touch the values stored in it. Most specifically you must never	544	must not touch the values stored in it. Most specifically you must never
320	reinitialise it or call its set method.</p>	545	reinitialise it or call its <code>set</code> macro.</p>
321	<p>You cna check wether an event is active by calling the <code>ev_is_active
322	(watcher *)</code> macro. To see wether an event is outstanding (but the
323	callback for it has not been called yet) you cna use the <code>ev_is_pending
324	(watcher *)</code> macro.</p>
325	<p>Each and every callback receives the event loop pointer as first, the	546	<p>Each and every callback receives the event loop pointer as first, the
326	registered watcher structure as second, and a bitset of received events as	547	registered watcher structure as second, and a bitset of received events as
327	third argument.</p>	548	third argument.</p>
328	<p>The rceeived events usually include a single bit per event type received	549	<p>The received events usually include a single bit per event type received
329	(you can receive multiple events at the same time). The possible bit masks	550	(you can receive multiple events at the same time). The possible bit masks
330	are:</p>	551	are:</p>
331	<dl>	552	<dl>
332	<dt>EV_READ</dt>	553	<dt><code>EV_READ</code></dt>
333	<dt>EV_WRITE</dt>	554	<dt><code>EV_WRITE</code></dt>
334	<dd>	555	<dd>
335	<p>The file descriptor in the ev_io watcher has become readable and/or	556	<p>The file descriptor in the <code>ev_io</code> watcher has become readable and/or
336	writable.</p>	557	writable.</p>
337	</dd>	558	</dd>
338	<dt>EV_TIMEOUT</dt>	559	<dt><code>EV_TIMEOUT</code></dt>
339	<dd>
340	<p>The ev_timer watcher has timed out.</p>
341	</dd>	560	<dd>
342	<dt>EV_PERIODIC</dt>	561	<p>The <code>ev_timer</code> watcher has timed out.</p>
343	<dd>	562	</dd>
344	<p>The ev_periodic watcher has timed out.</p>	563	<dt><code>EV_PERIODIC</code></dt>
345	</dd>	564	<dd>
346	<dt>EV_SIGNAL</dt>	565	<p>The <code>ev_periodic</code> watcher has timed out.</p>
347	<dd>	566	</dd>
		567	<dt><code>EV_SIGNAL</code></dt>
		568	<dd>
348	<p>The signal specified in the ev_signal watcher has been received by a thread.</p>	569	<p>The signal specified in the <code>ev_signal</code> watcher has been received by a thread.</p>
349	</dd>
350	<dt>EV_CHILD</dt>
351	<dd>	570	</dd>
		571	<dt><code>EV_CHILD</code></dt>
		572	<dd>
352	<p>The pid specified in the ev_child watcher has received a status change.</p>	573	<p>The pid specified in the <code>ev_child</code> watcher has received a status change.</p>
353	</dd>
354	<dt>EV_IDLE</dt>
355	<dd>	574	</dd>
		575	<dt><code>EV_IDLE</code></dt>
		576	<dd>
356	<p>The ev_idle watcher has determined that you have nothing better to do.</p>	577	<p>The <code>ev_idle</code> watcher has determined that you have nothing better to do.</p>
357	</dd>
358	<dt>EV_PREPARE</dt>
359	<dt>EV_CHECK</dt>
360	<dd>	578	</dd>
		579	<dt><code>EV_PREPARE</code></dt>
		580	<dt><code>EV_CHECK</code></dt>
		581	<dd>
361	<p>All ev_prepare watchers are invoked just <i>before</i> <code>ev_loop</code> starts	582	<p>All <code>ev_prepare</code> watchers are invoked just <i>before</i> <code>ev_loop</code> starts
362	to gather new events, and all ev_check watchers are invoked just after	583	to gather new events, and all <code>ev_check</code> watchers are invoked just after
363	<code>ev_loop</code> has gathered them, but before it invokes any callbacks for any	584	<code>ev_loop</code> has gathered them, but before it invokes any callbacks for any
364	received events. Callbacks of both watcher types can start and stop as	585	received events. Callbacks of both watcher types can start and stop as
365	many watchers as they want, and all of them will be taken into account	586	many watchers as they want, and all of them will be taken into account
366	(for example, a ev_prepare watcher might start an idle watcher to keep	587	(for example, a <code>ev_prepare</code> watcher might start an idle watcher to keep
367	<code>ev_loop</code> from blocking).</p>	588	<code>ev_loop</code> from blocking).</p>
368	</dd>	589	</dd>
369	<dt>EV_ERROR</dt>	590	<dt><code>EV_ERROR</code></dt>
370	<dd>	591	<dd>
371	<p>An unspecified error has occured, the watcher has been stopped. This might	592	<p>An unspecified error has occured, the watcher has been stopped. This might
372	happen because the watcher could not be properly started because libev	593	happen because the watcher could not be properly started because libev
373	ran out of memory, a file descriptor was found to be closed or any other	594	ran out of memory, a file descriptor was found to be closed or any other
374	problem. You best act on it by reporting the problem and somehow coping	595	problem. You best act on it by reporting the problem and somehow coping
…		…
380	programs, though, so beware.</p>	601	programs, though, so beware.</p>
381	</dd>	602	</dd>
382	</dl>	603	</dl>
383		604
384	</div>	605	</div>
		606	<h2 id="SUMMARY_OF_GENERIC_WATCHER_FUNCTIONS">SUMMARY OF GENERIC WATCHER FUNCTIONS</h2>
		607	<div id="SUMMARY_OF_GENERIC_WATCHER_FUNCTIONS-2">
		608	<p>In the following description, <code>TYPE</code> stands for the watcher type,
		609	e.g. <code>timer</code> for <code>ev_timer</code> watchers and <code>io</code> for <code>ev_io</code> watchers.</p>
		610	<dl>
		611	<dt><code>ev_init</code> (ev_TYPE *watcher, callback)</dt>
		612	<dd>
		613	<p>This macro initialises the generic portion of a watcher. The contents
		614	of the watcher object can be arbitrary (so <code>malloc</code> will do). Only
		615	the generic parts of the watcher are initialised, you <i>need</i> to call
		616	the type-specific <code>ev_TYPE_set</code> macro afterwards to initialise the
		617	type-specific parts. For each type there is also a <code>ev_TYPE_init</code> macro
		618	which rolls both calls into one.</p>
		619	<p>You can reinitialise a watcher at any time as long as it has been stopped
		620	(or never started) and there are no pending events outstanding.</p>
		621	<p>The callbakc is always of type <code>void ()(ev_loop loop, ev_TYPE *watcher,
		622	int revents)</code>.</p>
		623	</dd>
		624	<dt><code>ev_TYPE_set</code> (ev_TYPE *, [args])</dt>
		625	<dd>
		626	<p>This macro initialises the type-specific parts of a watcher. You need to
		627	call <code>ev_init</code> at least once before you call this macro, but you can
		628	call <code>ev_TYPE_set</code> any number of times. You must not, however, call this
		629	macro on a watcher that is active (it can be pending, however, which is a
		630	difference to the <code>ev_init</code> macro).</p>
		631	<p>Although some watcher types do not have type-specific arguments
		632	(e.g. <code>ev_prepare</code>) you still need to call its <code>set</code> macro.</p>
		633	</dd>
		634	<dt><code>ev_TYPE_init</code> (ev_TYPE *watcher, callback, [args])</dt>
		635	<dd>
		636	<p>This convinience macro rolls both <code>ev_init</code> and <code>ev_TYPE_set</code> macro
		637	calls into a single call. This is the most convinient method to initialise
		638	a watcher. The same limitations apply, of course.</p>
		639	</dd>
		640	<dt><code>ev_TYPE_start</code> (loop , ev_TYPE watcher)</dt>
		641	<dd>
		642	<p>Starts (activates) the given watcher. Only active watchers will receive
		643	events. If the watcher is already active nothing will happen.</p>
		644	</dd>
		645	<dt><code>ev_TYPE_stop</code> (loop , ev_TYPE watcher)</dt>
		646	<dd>
		647	<p>Stops the given watcher again (if active) and clears the pending
		648	status. It is possible that stopped watchers are pending (for example,
		649	non-repeating timers are being stopped when they become pending), but
		650	<code>ev_TYPE_stop</code> ensures that the watcher is neither active nor pending. If
		651	you want to free or reuse the memory used by the watcher it is therefore a
		652	good idea to always call its <code>ev_TYPE_stop</code> function.</p>
		653	</dd>
		654	<dt>bool ev_is_active (ev_TYPE *watcher)</dt>
		655	<dd>
		656	<p>Returns a true value iff the watcher is active (i.e. it has been started
		657	and not yet been stopped). As long as a watcher is active you must not modify
		658	it.</p>
		659	</dd>
		660	<dt>bool ev_is_pending (ev_TYPE *watcher)</dt>
		661	<dd>
		662	<p>Returns a true value iff the watcher is pending, (i.e. it has outstanding
		663	events but its callback has not yet been invoked). As long as a watcher
		664	is pending (but not active) you must not call an init function on it (but
		665	<code>ev_TYPE_set</code> is safe) and you must make sure the watcher is available to
		666	libev (e.g. you cnanot <code>free ()</code> it).</p>
		667	</dd>
		668	<dt>callback = ev_cb (ev_TYPE *watcher)</dt>
		669	<dd>
		670	<p>Returns the callback currently set on the watcher.</p>
		671	</dd>
		672	<dt>ev_cb_set (ev_TYPE *watcher, callback)</dt>
		673	<dd>
		674	<p>Change the callback. You can change the callback at virtually any time
		675	(modulo threads).</p>
		676	</dd>
		677	</dl>
		678
		679
		680
		681
		682
		683	</div>
385	<h2 id="ASSOCIATING_CUSTOM_DATA_WITH_A_WATCH">ASSOCIATING CUSTOM DATA WITH A WATCHER</h2>	684	<h2 id="ASSOCIATING_CUSTOM_DATA_WITH_A_WATCH">ASSOCIATING CUSTOM DATA WITH A WATCHER</h2>
386	<div id="ASSOCIATING_CUSTOM_DATA_WITH_A_WATCH-2">	685	<div id="ASSOCIATING_CUSTOM_DATA_WITH_A_WATCH-2">
387	<p>Each watcher has, by default, a member <code>void *data</code> that you can change	686	<p>Each watcher has, by default, a member <code>void *data</code> that you can change
388	and read at any time, libev will completely ignore it. This cna be used	687	and read at any time, libev will completely ignore it. This can be used
389	to associate arbitrary data with your watcher. If you need more data and	688	to associate arbitrary data with your watcher. If you need more data and
390	don't want to allocate memory and store a pointer to it in that data	689	don't want to allocate memory and store a pointer to it in that data
391	member, you can also "subclass" the watcher type and provide your own	690	member, you can also "subclass" the watcher type and provide your own
392	data:</p>	691	data:</p>
393	<pre> struct my_io	692	<pre> struct my_io
…		…
419	<h1 id="WATCHER_TYPES">WATCHER TYPES</h1><p><a href="#TOP" class="toplink">Top</a></p>	718	<h1 id="WATCHER_TYPES">WATCHER TYPES</h1><p><a href="#TOP" class="toplink">Top</a></p>
420	<div id="WATCHER_TYPES_CONTENT">	719	<div id="WATCHER_TYPES_CONTENT">
421	<p>This section describes each watcher in detail, but will not repeat	720	<p>This section describes each watcher in detail, but will not repeat
422	information given in the last section.</p>	721	information given in the last section.</p>
423		722
		723
		724
		725
		726
424	</div>	727	</div>
425	<h2 id="struct_ev_io_is_my_file_descriptor_r">struct ev_io - is my file descriptor readable or writable</h2>	728	<h2 id="code_ev_io_code_is_this_file_descrip"><code>ev_io</code> - is this file descriptor readable or writable</h2>
426	<div id="struct_ev_io_is_my_file_descriptor_r-2">	729	<div id="code_ev_io_code_is_this_file_descrip-2">
427	<p>I/O watchers check wether a file descriptor is readable or writable	730	<p>I/O watchers check whether a file descriptor is readable or writable
428	in each iteration of the event loop (This behaviour is called	731	in each iteration of the event loop (This behaviour is called
429	level-triggering because you keep receiving events as long as the	732	level-triggering because you keep receiving events as long as the
430	condition persists. Remember you cna stop the watcher if you don't want to	733	condition persists. Remember you can stop the watcher if you don't want to
431	act on the event and neither want to receive future events).</p>	734	act on the event and neither want to receive future events).</p>
		735	<p>In general you can register as many read and/or write event watchers per
		736	fd as you want (as long as you don't confuse yourself). Setting all file
		737	descriptors to non-blocking mode is also usually a good idea (but not
		738	required if you know what you are doing).</p>
		739	<p>You have to be careful with dup'ed file descriptors, though. Some backends
		740	(the linux epoll backend is a notable example) cannot handle dup'ed file
		741	descriptors correctly if you register interest in two or more fds pointing
		742	to the same underlying file/socket etc. description (that is, they share
		743	the same underlying "file open").</p>
		744	<p>If you must do this, then force the use of a known-to-be-good backend
		745	(at the time of this writing, this includes only <code>EVBACKEND_SELECT</code> and
		746	<code>EVBACKEND_POLL</code>).</p>
432	<dl>	747	<dl>
433	<dt>ev_io_init (ev_io *, callback, int fd, int events)</dt>	748	<dt>ev_io_init (ev_io *, callback, int fd, int events)</dt>
434	<dt>ev_io_set (ev_io *, int fd, int events)</dt>	749	<dt>ev_io_set (ev_io *, int fd, int events)</dt>
435	<dd>	750	<dd>
436	<p>Configures an ev_io watcher. The fd is the file descriptor to rceeive	751	<p>Configures an <code>ev_io</code> watcher. The fd is the file descriptor to rceeive
437	events for and events is either <code>EV_READ</code>, <code>EV_WRITE</code> or <code>EV_READ \|	752	events for and events is either <code>EV_READ</code>, <code>EV_WRITE</code> or <code>EV_READ \|
438	EV_WRITE</code> to receive the given events.</p>	753	EV_WRITE</code> to receive the given events.</p>
		754	<p>Please note that most of the more scalable backend mechanisms (for example
		755	epoll and solaris ports) can result in spurious readyness notifications
		756	for file descriptors, so you practically need to use non-blocking I/O (and
		757	treat callback invocation as hint only), or retest separately with a safe
		758	interface before doing I/O (XLib can do this), or force the use of either
		759	<code>EVBACKEND_SELECT</code> or <code>EVBACKEND_POLL</code>, which don't suffer from this
		760	problem. Also note that it is quite easy to have your callback invoked
		761	when the readyness condition is no longer valid even when employing
		762	typical ways of handling events, so its a good idea to use non-blocking
		763	I/O unconditionally.</p>
439	</dd>	764	</dd>
440	</dl>	765	</dl>
		766	<p>Example: call <code>stdin_readable_cb</code> when STDIN_FILENO has become, well
		767	readable, but only once. Since it is likely line-buffered, you could
		768	attempt to read a whole line in the callback:</p>
		769	<pre> static void
		770	stdin_readable_cb (struct ev_loop loop, struct ev_io w, int revents)
		771	{
		772	ev_io_stop (loop, w);
		773	.. read from stdin here (or from w->fd) and haqndle any I/O errors
		774	}
441		775
		776	...
		777	struct ev_loop *loop = ev_default_init (0);
		778	struct ev_io stdin_readable;
		779	ev_io_init (&stdin_readable, stdin_readable_cb, STDIN_FILENO, EV_READ);
		780	ev_io_start (loop, &stdin_readable);
		781	ev_loop (loop, 0);
		782
		783
		784
		785
		786	</pre>
		787
442	</div>	788	</div>
443	<h2 id="struct_ev_timer_relative_and_optiona">struct ev_timer - relative and optionally recurring timeouts</h2>	789	<h2 id="code_ev_timer_code_relative_and_opti"><code>ev_timer</code> - relative and optionally recurring timeouts</h2>
444	<div id="struct_ev_timer_relative_and_optiona-2">	790	<div id="code_ev_timer_code_relative_and_opti-2">
445	<p>Timer watchers are simple relative timers that generate an event after a	791	<p>Timer watchers are simple relative timers that generate an event after a
446	given time, and optionally repeating in regular intervals after that.</p>	792	given time, and optionally repeating in regular intervals after that.</p>
447	<p>The timers are based on real time, that is, if you register an event that	793	<p>The timers are based on real time, that is, if you register an event that
448	times out after an hour and youreset your system clock to last years	794	times out after an hour and you reset your system clock to last years
449	time, it will still time out after (roughly) and hour. "Roughly" because	795	time, it will still time out after (roughly) and hour. "Roughly" because
450	detecting time jumps is hard, and soem inaccuracies are unavoidable (the	796	detecting time jumps is hard, and some inaccuracies are unavoidable (the
451	monotonic clock option helps a lot here).</p>	797	monotonic clock option helps a lot here).</p>
		798	<p>The relative timeouts are calculated relative to the <code>ev_now ()</code>
		799	time. This is usually the right thing as this timestamp refers to the time
		800	of the event triggering whatever timeout you are modifying/starting. If
		801	you suspect event processing to be delayed and you <i>need</i> to base the timeout
		802	on the current time, use something like this to adjust for this:</p>
		803	<pre> ev_timer_set (&timer, after + ev_now () - ev_time (), 0.);
		804
		805	</pre>
		806	<p>The callback is guarenteed to be invoked only when its timeout has passed,
		807	but if multiple timers become ready during the same loop iteration then
		808	order of execution is undefined.</p>
452	<dl>	809	<dl>
453	<dt>ev_timer_init (ev_timer *, callback, ev_tstamp after, ev_tstamp repeat)</dt>	810	<dt>ev_timer_init (ev_timer *, callback, ev_tstamp after, ev_tstamp repeat)</dt>
454	<dt>ev_timer_set (ev_timer *, ev_tstamp after, ev_tstamp repeat)</dt>	811	<dt>ev_timer_set (ev_timer *, ev_tstamp after, ev_tstamp repeat)</dt>
455	<dd>	812	<dd>
456	<p>Configure the timer to trigger after <code>after</code> seconds. If <code>repeat</code> is	813	<p>Configure the timer to trigger after <code>after</code> seconds. If <code>repeat</code> is
…		…
458	timer will automatically be configured to trigger again <code>repeat</code> seconds	815	timer will automatically be configured to trigger again <code>repeat</code> seconds
459	later, again, and again, until stopped manually.</p>	816	later, again, and again, until stopped manually.</p>
460	<p>The timer itself will do a best-effort at avoiding drift, that is, if you	817	<p>The timer itself will do a best-effort at avoiding drift, that is, if you
461	configure a timer to trigger every 10 seconds, then it will trigger at	818	configure a timer to trigger every 10 seconds, then it will trigger at
462	exactly 10 second intervals. If, however, your program cannot keep up with	819	exactly 10 second intervals. If, however, your program cannot keep up with
463	the timer (ecause it takes longer than those 10 seconds to do stuff) the	820	the timer (because it takes longer than those 10 seconds to do stuff) the
464	timer will not fire more than once per event loop iteration.</p>	821	timer will not fire more than once per event loop iteration.</p>
465	</dd>	822	</dd>
466	<dt>ev_timer_again (loop)</dt>	823	<dt>ev_timer_again (loop)</dt>
467	<dd>	824	<dd>
468	<p>This will act as if the timer timed out and restart it again if it is	825	<p>This will act as if the timer timed out and restart it again if it is
…		…
472	value), or reset the running timer to the repeat value.</p>	829	value), or reset the running timer to the repeat value.</p>
473	<p>This sounds a bit complicated, but here is a useful and typical	830	<p>This sounds a bit complicated, but here is a useful and typical
474	example: Imagine you have a tcp connection and you want a so-called idle	831	example: Imagine you have a tcp connection and you want a so-called idle
475	timeout, that is, you want to be called when there have been, say, 60	832	timeout, that is, you want to be called when there have been, say, 60
476	seconds of inactivity on the socket. The easiest way to do this is to	833	seconds of inactivity on the socket. The easiest way to do this is to
477	configure an ev_timer with after=repeat=60 and calling ev_timer_again each	834	configure an <code>ev_timer</code> with after=repeat=60 and calling ev_timer_again each
478	time you successfully read or write some data. If you go into an idle	835	time you successfully read or write some data. If you go into an idle
479	state where you do not expect data to travel on the socket, you can stop	836	state where you do not expect data to travel on the socket, you can stop
480	the timer, and again will automatically restart it if need be.</p>	837	the timer, and again will automatically restart it if need be.</p>
481	</dd>	838	</dd>
482	</dl>	839	</dl>
		840	<p>Example: create a timer that fires after 60 seconds.</p>
		841	<pre> static void
		842	one_minute_cb (struct ev_loop loop, struct ev_timer w, int revents)
		843	{
		844	.. one minute over, w is actually stopped right here
		845	}
483		846
		847	struct ev_timer mytimer;
		848	ev_timer_init (&mytimer, one_minute_cb, 60., 0.);
		849	ev_timer_start (loop, &mytimer);
		850
		851	</pre>
		852	<p>Example: create a timeout timer that times out after 10 seconds of
		853	inactivity.</p>
		854	<pre> static void
		855	timeout_cb (struct ev_loop loop, struct ev_timer w, int revents)
		856	{
		857	.. ten seconds without any activity
		858	}
		859
		860	struct ev_timer mytimer;
		861	ev_timer_init (&mytimer, timeout_cb, 0., 10.); /* note, only repeat used */
		862	ev_timer_again (&mytimer); /* start timer */
		863	ev_loop (loop, 0);
		864
		865	// and in some piece of code that gets executed on any "activity":
		866	// reset the timeout to start ticking again at 10 seconds
		867	ev_timer_again (&mytimer);
		868
		869
		870
		871
		872	</pre>
		873
484	</div>	874	</div>
485	<h2 id="ev_periodic">ev_periodic</h2>	875	<h2 id="code_ev_periodic_code_to_cron_or_not"><code>ev_periodic</code> - to cron or not to cron</h2>
486	<div id="ev_periodic_CONTENT">	876	<div id="code_ev_periodic_code_to_cron_or_not-2">
487	<p>Periodic watchers are also timers of a kind, but they are very versatile	877	<p>Periodic watchers are also timers of a kind, but they are very versatile
488	(and unfortunately a bit complex).</p>	878	(and unfortunately a bit complex).</p>
489	<p>Unlike ev_timer's, they are not based on real time (or relative time)	879	<p>Unlike <code>ev_timer</code>'s, they are not based on real time (or relative time)
490	but on wallclock time (absolute time). You can tell a periodic watcher	880	but on wallclock time (absolute time). You can tell a periodic watcher
491	to trigger "at" some specific point in time. For example, if you tell a	881	to trigger "at" some specific point in time. For example, if you tell a
492	periodic watcher to trigger in 10 seconds (by specifiying e.g. c<ev_now ()	882	periodic watcher to trigger in 10 seconds (by specifiying e.g. <code>ev_now ()
493	+ 10.>) and then reset your system clock to the last year, then it will	883	+ 10.</code>) and then reset your system clock to the last year, then it will
494	take a year to trigger the event (unlike an ev_timer, which would trigger	884	take a year to trigger the event (unlike an <code>ev_timer</code>, which would trigger
495	roughly 10 seconds later and of course not if you reset your system time	885	roughly 10 seconds later and of course not if you reset your system time
496	again).</p>	886	again).</p>
497	<p>They can also be used to implement vastly more complex timers, such as	887	<p>They can also be used to implement vastly more complex timers, such as
498	triggering an event on eahc midnight, local time.</p>	888	triggering an event on eahc midnight, local time.</p>
		889	<p>As with timers, the callback is guarenteed to be invoked only when the
		890	time (<code>at</code>) has been passed, but if multiple periodic timers become ready
		891	during the same loop iteration then order of execution is undefined.</p>
499	<dl>	892	<dl>
500	<dt>ev_periodic_init (ev_periodic *, callback, ev_tstamp at, ev_tstamp interval, reschedule_cb)</dt>	893	<dt>ev_periodic_init (ev_periodic *, callback, ev_tstamp at, ev_tstamp interval, reschedule_cb)</dt>
501	<dt>ev_periodic_set (ev_periodic *, ev_tstamp after, ev_tstamp repeat, reschedule_cb)</dt>	894	<dt>ev_periodic_set (ev_periodic *, ev_tstamp after, ev_tstamp repeat, reschedule_cb)</dt>
502	<dd>	895	<dd>
503	<p>Lots of arguments, lets sort it out... There are basically three modes of	896	<p>Lots of arguments, lets sort it out... There are basically three modes of
504	operation, and we will explain them from simplest to complex:</p>	897	operation, and we will explain them from simplest to complex:</p>
505
506
507
508
509	<p>	898	<p>
510	<dl>	899	<dl>
511	<dt>* absolute timer (interval = reschedule_cb = 0)</dt>	900	<dt>* absolute timer (interval = reschedule_cb = 0)</dt>
512	<dd>	901	<dd>
513	<p>In this configuration the watcher triggers an event at the wallclock time	902	<p>In this configuration the watcher triggers an event at the wallclock time
…		…
525	<pre> ev_periodic_set (&periodic, 0., 3600., 0);	914	<pre> ev_periodic_set (&periodic, 0., 3600., 0);
526		915
527	</pre>	916	</pre>
528	<p>This doesn't mean there will always be 3600 seconds in between triggers,	917	<p>This doesn't mean there will always be 3600 seconds in between triggers,
529	but only that the the callback will be called when the system time shows a	918	but only that the the callback will be called when the system time shows a
530	full hour (UTC), or more correct, when the system time is evenly divisible	919	full hour (UTC), or more correctly, when the system time is evenly divisible
531	by 3600.</p>	920	by 3600.</p>
532	<p>Another way to think about it (for the mathematically inclined) is that	921	<p>Another way to think about it (for the mathematically inclined) is that
533	ev_periodic will try to run the callback in this mode at the next possible	922	<code>ev_periodic</code> will try to run the callback in this mode at the next possible
534	time where <code>time = at (mod interval)</code>, regardless of any time jumps.</p>	923	time where <code>time = at (mod interval)</code>, regardless of any time jumps.</p>
535	</dd>	924	</dd>
536	<dt>* manual reschedule mode (reschedule_cb = callback)</dt>	925	<dt>* manual reschedule mode (reschedule_cb = callback)</dt>
537	<dd>	926	<dd>
538	<p>In this mode the values for <code>interval</code> and <code>at</code> are both being	927	<p>In this mode the values for <code>interval</code> and <code>at</code> are both being
539	ignored. Instead, each time the periodic watcher gets scheduled, the	928	ignored. Instead, each time the periodic watcher gets scheduled, the
540	reschedule callback will be called with the watcher as first, and the	929	reschedule callback will be called with the watcher as first, and the
541	current time as second argument.</p>	930	current time as second argument.</p>
542	<p>NOTE: <i>This callback MUST NOT stop or destroy the periodic or any other	931	<p>NOTE: <i>This callback MUST NOT stop or destroy any periodic watcher,
543	periodic watcher, ever, or make any event loop modificstions</i>. If you need	932	ever, or make any event loop modifications</i>. If you need to stop it,
544	to stop it, return 1e30 (or so, fudge fudge) and stop it afterwards.</p>	933	return <code>now + 1e30</code> (or so, fudge fudge) and stop it afterwards (e.g. by
		934	starting a prepare watcher).</p>
545	<p>Its prototype is c<ev_tstamp (reschedule_cb)(struct ev_periodic w,	935	<p>Its prototype is <code>ev_tstamp (reschedule_cb)(struct ev_periodic w,
546	ev_tstamp now)>, e.g.:</p>	936	ev_tstamp now)</code>, e.g.:</p>
547	<pre> static ev_tstamp my_rescheduler (struct ev_periodic *w, ev_tstamp now)	937	<pre> static ev_tstamp my_rescheduler (struct ev_periodic *w, ev_tstamp now)
548	{	938	{
549	return now + 60.;	939	return now + 60.;
550	}	940	}
551		941
552	</pre>	942	</pre>
553	<p>It must return the next time to trigger, based on the passed time value	943	<p>It must return the next time to trigger, based on the passed time value
554	(that is, the lowest time value larger than to the second argument). It	944	(that is, the lowest time value larger than to the second argument). It
555	will usually be called just before the callback will be triggered, but	945	will usually be called just before the callback will be triggered, but
556	might be called at other times, too.</p>	946	might be called at other times, too.</p>
		947	<p>NOTE: <i>This callback must always return a time that is later than the
		948	passed <code>now</code> value</i>. Not even <code>now</code> itself will do, it <i>must</i> be larger.</p>
557	<p>This can be used to create very complex timers, such as a timer that	949	<p>This can be used to create very complex timers, such as a timer that
558	triggers on each midnight, local time. To do this, you would calculate the	950	triggers on each midnight, local time. To do this, you would calculate the
559	next midnight after <code>now</code> and return the timestamp value for this. How you do this	951	next midnight after <code>now</code> and return the timestamp value for this. How
560	is, again, up to you (but it is not trivial).</p>	952	you do this is, again, up to you (but it is not trivial, which is the main
		953	reason I omitted it as an example).</p>
561	</dd>	954	</dd>
562	</dl>	955	</dl>
563	</p>	956	</p>
564	</dd>	957	</dd>
565	<dt>ev_periodic_again (loop, ev_periodic *)</dt>	958	<dt>ev_periodic_again (loop, ev_periodic *)</dt>
…		…
568	when you changed some parameters or the reschedule callback would return	961	when you changed some parameters or the reschedule callback would return
569	a different time than the last time it was called (e.g. in a crond like	962	a different time than the last time it was called (e.g. in a crond like
570	program when the crontabs have changed).</p>	963	program when the crontabs have changed).</p>
571	</dd>	964	</dd>
572	</dl>	965	</dl>
		966	<p>Example: call a callback every hour, or, more precisely, whenever the
		967	system clock is divisible by 3600. The callback invocation times have
		968	potentially a lot of jittering, but good long-term stability.</p>
		969	<pre> static void
		970	clock_cb (struct ev_loop loop, struct ev_io w, int revents)
		971	{
		972	... its now a full hour (UTC, or TAI or whatever your clock follows)
		973	}
573		974
		975	struct ev_periodic hourly_tick;
		976	ev_periodic_init (&hourly_tick, clock_cb, 0., 3600., 0);
		977	ev_periodic_start (loop, &hourly_tick);
		978
		979	</pre>
		980	<p>Example: the same as above, but use a reschedule callback to do it:</p>
		981	<pre> #include <math.h>
		982
		983	static ev_tstamp
		984	my_scheduler_cb (struct ev_periodic *w, ev_tstamp now)
		985	{
		986	return fmod (now, 3600.) + 3600.;
		987	}
		988
		989	ev_periodic_init (&hourly_tick, clock_cb, 0., 0., my_scheduler_cb);
		990
		991	</pre>
		992	<p>Example: call a callback every hour, starting now:</p>
		993	<pre> struct ev_periodic hourly_tick;
		994	ev_periodic_init (&hourly_tick, clock_cb,
		995	fmod (ev_now (loop), 3600.), 3600., 0);
		996	ev_periodic_start (loop, &hourly_tick);
		997
		998
		999
		1000
		1001	</pre>
		1002
574	</div>	1003	</div>
575	<h2 id="ev_signal_signal_me_when_a_signal_ge">ev_signal - signal me when a signal gets signalled</h2>	1004	<h2 id="code_ev_signal_code_signal_me_when_a"><code>ev_signal</code> - signal me when a signal gets signalled</h2>
576	<div id="ev_signal_signal_me_when_a_signal_ge-2">	1005	<div id="code_ev_signal_code_signal_me_when_a-2">
577	<p>Signal watchers will trigger an event when the process receives a specific	1006	<p>Signal watchers will trigger an event when the process receives a specific
578	signal one or more times. Even though signals are very asynchronous, libev	1007	signal one or more times. Even though signals are very asynchronous, libev
579	will try its best to deliver signals synchronously, i.e. as part of the	1008	will try it's best to deliver signals synchronously, i.e. as part of the
580	normal event processing, like any other event.</p>	1009	normal event processing, like any other event.</p>
581	<p>You cna configure as many watchers as you like per signal. Only when the	1010	<p>You can configure as many watchers as you like per signal. Only when the
582	first watcher gets started will libev actually register a signal watcher	1011	first watcher gets started will libev actually register a signal watcher
583	with the kernel (thus it coexists with your own signal handlers as long	1012	with the kernel (thus it coexists with your own signal handlers as long
584	as you don't register any with libev). Similarly, when the last signal	1013	as you don't register any with libev). Similarly, when the last signal
585	watcher for a signal is stopped libev will reset the signal handler to	1014	watcher for a signal is stopped libev will reset the signal handler to
586	SIG_DFL (regardless of what it was set to before).</p>	1015	SIG_DFL (regardless of what it was set to before).</p>
…		…
591	<p>Configures the watcher to trigger on the given signal number (usually one	1020	<p>Configures the watcher to trigger on the given signal number (usually one
592	of the <code>SIGxxx</code> constants).</p>	1021	of the <code>SIGxxx</code> constants).</p>
593	</dd>	1022	</dd>
594	</dl>	1023	</dl>
595		1024
		1025
		1026
		1027
		1028
596	</div>	1029	</div>
597	<h2 id="ev_child_wait_for_pid_status_changes">ev_child - wait for pid status changes</h2>	1030	<h2 id="code_ev_child_code_wait_for_pid_stat"><code>ev_child</code> - wait for pid status changes</h2>
598	<div id="ev_child_wait_for_pid_status_changes-2">	1031	<div id="code_ev_child_code_wait_for_pid_stat-2">
599	<p>Child watchers trigger when your process receives a SIGCHLD in response to	1032	<p>Child watchers trigger when your process receives a SIGCHLD in response to
600	some child status changes (most typically when a child of yours dies).</p>	1033	some child status changes (most typically when a child of yours dies).</p>
601	<dl>	1034	<dl>
602	<dt>ev_child_init (ev_child *, callback, int pid)</dt>	1035	<dt>ev_child_init (ev_child *, callback, int pid)</dt>
603	<dt>ev_child_set (ev_child *, int pid)</dt>	1036	<dt>ev_child_set (ev_child *, int pid)</dt>
604	<dd>	1037	<dd>
605	<p>Configures the watcher to wait for status changes of process <code>pid</code> (or	1038	<p>Configures the watcher to wait for status changes of process <code>pid</code> (or
606	<i>any</i> process if <code>pid</code> is specified as <code>0</code>). The callback can look	1039	<i>any</i> process if <code>pid</code> is specified as <code>0</code>). The callback can look
607	at the <code>rstatus</code> member of the <code>ev_child</code> watcher structure to see	1040	at the <code>rstatus</code> member of the <code>ev_child</code> watcher structure to see
608	the status word (use the macros from <code>sys/wait.h</code>). The <code>rpid</code> member	1041	the status word (use the macros from <code>sys/wait.h</code> and see your systems
		1042	<code>waitpid</code> documentation). The <code>rpid</code> member contains the pid of the
609	contains the pid of the process causing the status change.</p>	1043	process causing the status change.</p>
610	</dd>	1044	</dd>
611	</dl>	1045	</dl>
		1046	<p>Example: try to exit cleanly on SIGINT and SIGTERM.</p>
		1047	<pre> static void
		1048	sigint_cb (struct ev_loop loop, struct ev_signal w, int revents)
		1049	{
		1050	ev_unloop (loop, EVUNLOOP_ALL);
		1051	}
612		1052
		1053	struct ev_signal signal_watcher;
		1054	ev_signal_init (&signal_watcher, sigint_cb, SIGINT);
		1055	ev_signal_start (loop, &sigint_cb);
		1056
		1057
		1058
		1059
		1060	</pre>
		1061
613	</div>	1062	</div>
614	<h2 id="ev_idle_when_you_ve_got_nothing_bett">ev_idle - when you've got nothing better to do</h2>	1063	<h2 id="code_ev_idle_code_when_you_ve_got_no"><code>ev_idle</code> - when you've got nothing better to do</h2>
615	<div id="ev_idle_when_you_ve_got_nothing_bett-2">	1064	<div id="code_ev_idle_code_when_you_ve_got_no-2">
616	<p>Idle watchers trigger events when there are no other I/O or timer (or	1065	<p>Idle watchers trigger events when there are no other events are pending
617	periodic) events pending. That is, as long as your process is busy	1066	(prepare, check and other idle watchers do not count). That is, as long
618	handling sockets or timeouts it will not be called. But when your process	1067	as your process is busy handling sockets or timeouts (or even signals,
619	is idle all idle watchers are being called again and again - until	1068	imagine) it will not be triggered. But when your process is idle all idle
		1069	watchers are being called again and again, once per event loop iteration -
620	stopped, that is, or your process receives more events.</p>	1070	until stopped, that is, or your process receives more events and becomes
		1071	busy.</p>
621	<p>The most noteworthy effect is that as long as any idle watchers are	1072	<p>The most noteworthy effect is that as long as any idle watchers are
622	active, the process will not block when waiting for new events.</p>	1073	active, the process will not block when waiting for new events.</p>
623	<p>Apart from keeping your process non-blocking (which is a useful	1074	<p>Apart from keeping your process non-blocking (which is a useful
624	effect on its own sometimes), idle watchers are a good place to do	1075	effect on its own sometimes), idle watchers are a good place to do
625	"pseudo-background processing", or delay processing stuff to after the	1076	"pseudo-background processing", or delay processing stuff to after the
…		…
630	<p>Initialises and configures the idle watcher - it has no parameters of any	1081	<p>Initialises and configures the idle watcher - it has no parameters of any
631	kind. There is a <code>ev_idle_set</code> macro, but using it is utterly pointless,	1082	kind. There is a <code>ev_idle_set</code> macro, but using it is utterly pointless,
632	believe me.</p>	1083	believe me.</p>
633	</dd>	1084	</dd>
634	</dl>	1085	</dl>
		1086	<p>Example: dynamically allocate an <code>ev_idle</code>, start it, and in the
		1087	callback, free it. Alos, use no error checking, as usual.</p>
		1088	<pre> static void
		1089	idle_cb (struct ev_loop loop, struct ev_idle w, int revents)
		1090	{
		1091	free (w);
		1092	// now do something you wanted to do when the program has
		1093	// no longer asnything immediate to do.
		1094	}
635		1095
		1096	struct ev_idle *idle_watcher = malloc (sizeof (struct ev_idle));
		1097	ev_idle_init (idle_watcher, idle_cb);
		1098	ev_idle_start (loop, idle_cb);
		1099
		1100
		1101
		1102
		1103	</pre>
		1104
636	</div>	1105	</div>
637	<h2 id="prepare_and_check_your_hooks_into_th">prepare and check - your hooks into the event loop</h2>	1106	<h2 id="code_ev_prepare_code_and_code_ev_che"><code>ev_prepare</code> and <code>ev_check</code> - customise your event loop</h2>
638	<div id="prepare_and_check_your_hooks_into_th-2">	1107	<div id="code_ev_prepare_code_and_code_ev_che-2">
639	<p>Prepare and check watchers usually (but not always) are used in	1108	<p>Prepare and check watchers are usually (but not always) used in tandem:
640	tandom. Prepare watchers get invoked before the process blocks and check	1109	prepare watchers get invoked before the process blocks and check watchers
641	watchers afterwards.</p>	1110	afterwards.</p>
642	<p>Their main purpose is to integrate other event mechanisms into libev. This	1111	<p>Their main purpose is to integrate other event mechanisms into libev and
643	could be used, for example, to track variable changes, implement your own	1112	their use is somewhat advanced. This could be used, for example, to track
644	watchers, integrate net-snmp or a coroutine library and lots more.</p>	1113	variable changes, implement your own watchers, integrate net-snmp or a
		1114	coroutine library and lots more.</p>
645	<p>This is done by examining in each prepare call which file descriptors need	1115	<p>This is done by examining in each prepare call which file descriptors need
646	to be watched by the other library, registering ev_io watchers for them	1116	to be watched by the other library, registering <code>ev_io</code> watchers for
647	and starting an ev_timer watcher for any timeouts (many libraries provide	1117	them and starting an <code>ev_timer</code> watcher for any timeouts (many libraries
648	just this functionality). Then, in the check watcher you check for any	1118	provide just this functionality). Then, in the check watcher you check for
649	events that occured (by making your callbacks set soem flags for example)	1119	any events that occured (by checking the pending status of all watchers
650	and call back into the library.</p>	1120	and stopping them) and call back into the library. The I/O and timer
		1121	callbacks will never actually be called (but must be valid nevertheless,
		1122	because you never know, you know?).</p>
651	<p>As another example, the perl Coro module uses these hooks to integrate	1123	<p>As another example, the Perl Coro module uses these hooks to integrate
652	coroutines into libev programs, by yielding to other active coroutines	1124	coroutines into libev programs, by yielding to other active coroutines
653	during each prepare and only letting the process block if no coroutines	1125	during each prepare and only letting the process block if no coroutines
654	are ready to run.</p>	1126	are ready to run (it's actually more complicated: it only runs coroutines
		1127	with priority higher than or equal to the event loop and one coroutine
		1128	of lower priority, but only once, using idle watchers to keep the event
		1129	loop from blocking if lower-priority coroutines are active, thus mapping
		1130	low-priority coroutines to idle/background tasks).</p>
655	<dl>	1131	<dl>
656	<dt>ev_prepare_init (ev_prepare *, callback)</dt>	1132	<dt>ev_prepare_init (ev_prepare *, callback)</dt>
657	<dt>ev_check_init (ev_check *, callback)</dt>	1133	<dt>ev_check_init (ev_check *, callback)</dt>
658	<dd>	1134	<dd>
659	<p>Initialises and configures the prepare or check watcher - they have no	1135	<p>Initialises and configures the prepare or check watcher - they have no
660	parameters of any kind. There are <code>ev_prepare_set</code> and <code>ev_check_set</code>	1136	parameters of any kind. There are <code>ev_prepare_set</code> and <code>ev_check_set</code>
661	macros, but using them is utterly, utterly pointless.</p>	1137	macros, but using them is utterly, utterly and completely pointless.</p>
662	</dd>	1138	</dd>
663	</dl>	1139	</dl>
		1140	<p>Example: TODO.</p>
		1141
		1142
		1143
		1144
		1145
		1146	</div>
		1147	<h2 id="code_ev_embed_code_when_one_backend_"><code>ev_embed</code> - when one backend isn't enough</h2>
		1148	<div id="code_ev_embed_code_when_one_backend_-2">
		1149	<p>This is a rather advanced watcher type that lets you embed one event loop
		1150	into another (currently only <code>ev_io</code> events are supported in the embedded
		1151	loop, other types of watchers might be handled in a delayed or incorrect
		1152	fashion and must not be used).</p>
		1153	<p>There are primarily two reasons you would want that: work around bugs and
		1154	prioritise I/O.</p>
		1155	<p>As an example for a bug workaround, the kqueue backend might only support
		1156	sockets on some platform, so it is unusable as generic backend, but you
		1157	still want to make use of it because you have many sockets and it scales
		1158	so nicely. In this case, you would create a kqueue-based loop and embed it
		1159	into your default loop (which might use e.g. poll). Overall operation will
		1160	be a bit slower because first libev has to poll and then call kevent, but
		1161	at least you can use both at what they are best.</p>
		1162	<p>As for prioritising I/O: rarely you have the case where some fds have
		1163	to be watched and handled very quickly (with low latency), and even
		1164	priorities and idle watchers might have too much overhead. In this case
		1165	you would put all the high priority stuff in one loop and all the rest in
		1166	a second one, and embed the second one in the first.</p>
		1167	<p>As long as the watcher is active, the callback will be invoked every time
		1168	there might be events pending in the embedded loop. The callback must then
		1169	call <code>ev_embed_sweep (mainloop, watcher)</code> to make a single sweep and invoke
		1170	their callbacks (you could also start an idle watcher to give the embedded
		1171	loop strictly lower priority for example). You can also set the callback
		1172	to <code>0</code>, in which case the embed watcher will automatically execute the
		1173	embedded loop sweep.</p>
		1174	<p>As long as the watcher is started it will automatically handle events. The
		1175	callback will be invoked whenever some events have been handled. You can
		1176	set the callback to <code>0</code> to avoid having to specify one if you are not
		1177	interested in that.</p>
		1178	<p>Also, there have not currently been made special provisions for forking:
		1179	when you fork, you not only have to call <code>ev_loop_fork</code> on both loops,
		1180	but you will also have to stop and restart any <code>ev_embed</code> watchers
		1181	yourself.</p>
		1182	<p>Unfortunately, not all backends are embeddable, only the ones returned by
		1183	<code>ev_embeddable_backends</code> are, which, unfortunately, does not include any
		1184	portable one.</p>
		1185	<p>So when you want to use this feature you will always have to be prepared
		1186	that you cannot get an embeddable loop. The recommended way to get around
		1187	this is to have a separate variables for your embeddable loop, try to
		1188	create it, and if that fails, use the normal loop for everything:</p>
		1189	<pre> struct ev_loop *loop_hi = ev_default_init (0);
		1190	struct ev_loop *loop_lo = 0;
		1191	struct ev_embed embed;
		1192
		1193	// see if there is a chance of getting one that works
		1194	// (remember that a flags value of 0 means autodetection)
		1195	loop_lo = ev_embeddable_backends () & ev_recommended_backends ()
		1196	? ev_loop_new (ev_embeddable_backends () & ev_recommended_backends ())
		1197	: 0;
		1198
		1199	// if we got one, then embed it, otherwise default to loop_hi
		1200	if (loop_lo)
		1201	{
		1202	ev_embed_init (&embed, 0, loop_lo);
		1203	ev_embed_start (loop_hi, &embed);
		1204	}
		1205	else
		1206	loop_lo = loop_hi;
		1207
		1208	</pre>
		1209	<dl>
		1210	<dt>ev_embed_init (ev_embed , callback, struct ev_loop embedded_loop)</dt>
		1211	<dt>ev_embed_set (ev_embed , callback, struct ev_loop embedded_loop)</dt>
		1212	<dd>
		1213	<p>Configures the watcher to embed the given loop, which must be
		1214	embeddable. If the callback is <code>0</code>, then <code>ev_embed_sweep</code> will be
		1215	invoked automatically, otherwise it is the responsibility of the callback
		1216	to invoke it (it will continue to be called until the sweep has been done,
		1217	if you do not want thta, you need to temporarily stop the embed watcher).</p>
		1218	</dd>
		1219	<dt>ev_embed_sweep (loop, ev_embed *)</dt>
		1220	<dd>
		1221	<p>Make a single, non-blocking sweep over the embedded loop. This works
		1222	similarly to <code>ev_loop (embedded_loop, EVLOOP_NONBLOCK)</code>, but in the most
		1223	apropriate way for embedded loops.</p>
		1224	</dd>
		1225	</dl>
		1226
		1227
		1228
		1229
664		1230
665	</div>	1231	</div>
666	<h1 id="OTHER_FUNCTIONS">OTHER FUNCTIONS</h1><p><a href="#TOP" class="toplink">Top</a></p>	1232	<h1 id="OTHER_FUNCTIONS">OTHER FUNCTIONS</h1><p><a href="#TOP" class="toplink">Top</a></p>
667	<div id="OTHER_FUNCTIONS_CONTENT">	1233	<div id="OTHER_FUNCTIONS_CONTENT">
668	<p>There are some other fucntions of possible interest. Described. Here. Now.</p>	1234	<p>There are some other functions of possible interest. Described. Here. Now.</p>
669	<dl>	1235	<dl>
670	<dt>ev_once (loop, int fd, int events, ev_tstamp timeout, callback)</dt>	1236	<dt>ev_once (loop, int fd, int events, ev_tstamp timeout, callback)</dt>
671	<dd>	1237	<dd>
672	<p>This function combines a simple timer and an I/O watcher, calls your	1238	<p>This function combines a simple timer and an I/O watcher, calls your
673	callback on whichever event happens first and automatically stop both	1239	callback on whichever event happens first and automatically stop both
674	watchers. This is useful if you want to wait for a single event on an fd	1240	watchers. This is useful if you want to wait for a single event on an fd
675	or timeout without havign to allocate/configure/start/stop/free one or	1241	or timeout without having to allocate/configure/start/stop/free one or
676	more watchers yourself.</p>	1242	more watchers yourself.</p>
677	<p>If <code>fd</code> is less than 0, then no I/O watcher will be started and events is	1243	<p>If <code>fd</code> is less than 0, then no I/O watcher will be started and events
678	ignored. Otherwise, an ev_io watcher for the given <code>fd</code> and <code>events</code> set	1244	is being ignored. Otherwise, an <code>ev_io</code> watcher for the given <code>fd</code> and
679	will be craeted and started.</p>	1245	<code>events</code> set will be craeted and started.</p>
680	<p>If <code>timeout</code> is less than 0, then no timeout watcher will be	1246	<p>If <code>timeout</code> is less than 0, then no timeout watcher will be
681	started. Otherwise an ev_timer watcher with after = <code>timeout</code> (and repeat	1247	started. Otherwise an <code>ev_timer</code> watcher with after = <code>timeout</code> (and
682	= 0) will be started.</p>	1248	repeat = 0) will be started. While <code>0</code> is a valid timeout, it is of
		1249	dubious value.</p>
683	<p>The callback has the type <code>void (cb)(int revents, void arg)</code> and	1250	<p>The callback has the type <code>void (cb)(int revents, void arg)</code> and gets
684	gets passed an events set (normally a combination of EV_ERROR, EV_READ,	1251	passed an <code>revents</code> set like normal event callbacks (a combination of
685	EV_WRITE or EV_TIMEOUT) and the <code>arg</code> value passed to <code>ev_once</code>:</p>	1252	<code>EV_ERROR</code>, <code>EV_READ</code>, <code>EV_WRITE</code> or <code>EV_TIMEOUT</code>) and the <code>arg</code>
		1253	value passed to <code>ev_once</code>:</p>
686	<pre> static void stdin_ready (int revents, void *arg)	1254	<pre> static void stdin_ready (int revents, void *arg)
687	{	1255	{
688	if (revents & EV_TIMEOUT)	1256	if (revents & EV_TIMEOUT)
689	/* doh, nothing entered */	1257	/* doh, nothing entered */;
690	else if (revents & EV_READ)	1258	else if (revents & EV_READ)
691	/* stdin might have data for us, joy! */	1259	/* stdin might have data for us, joy! */;
692	}	1260	}
693		1261
694	ev_once (STDIN_FILENO, EV_READm 10., stdin_ready, 0);	1262	ev_once (STDIN_FILENO, EV_READ, 10., stdin_ready, 0);
695		1263
696	</pre>	1264	</pre>
697	</dd>	1265	</dd>
698	<dt>ev_feed_event (loop, watcher, int events)</dt>	1266	<dt>ev_feed_event (ev_loop , watcher , int revents)</dt>
699	<dd>	1267	<dd>
700	<p>Feeds the given event set into the event loop, as if the specified event	1268	<p>Feeds the given event set into the event loop, as if the specified event
701	has happened for the specified watcher (which must be a pointer to an	1269	had happened for the specified watcher (which must be a pointer to an
702	initialised but not necessarily active event watcher).</p>	1270	initialised but not necessarily started event watcher).</p>
703	</dd>	1271	</dd>
704	<dt>ev_feed_fd_event (loop, int fd, int revents)</dt>	1272	<dt>ev_feed_fd_event (ev_loop *, int fd, int revents)</dt>
705	<dd>	1273	<dd>
706	<p>Feed an event on the given fd, as if a file descriptor backend detected it.</p>	1274	<p>Feed an event on the given fd, as if a file descriptor backend detected
		1275	the given events it.</p>
707	</dd>	1276	</dd>
708	<dt>ev_feed_signal_event (loop, int signum)</dt>	1277	<dt>ev_feed_signal_event (ev_loop *loop, int signum)</dt>
709	<dd>	1278	<dd>
710	<p>Feed an event as if the given signal occured (loop must be the default loop!).</p>	1279	<p>Feed an event as if the given signal occured (<code>loop</code> must be the default
		1280	loop!).</p>
711	</dd>	1281	</dd>
712	</dl>	1282	</dl>
		1283
		1284
		1285
		1286
		1287
		1288	</div>
		1289	<h1 id="LIBEVENT_EMULATION">LIBEVENT EMULATION</h1><p><a href="#TOP" class="toplink">Top</a></p>
		1290	<div id="LIBEVENT_EMULATION_CONTENT">
		1291	<p>Libev offers a compatibility emulation layer for libevent. It cannot
		1292	emulate the internals of libevent, so here are some usage hints:</p>
		1293	<dl>
		1294	<dt>* Use it by including <event.h>, as usual.</dt>
		1295	<dt>* The following members are fully supported: ev_base, ev_callback,
		1296	ev_arg, ev_fd, ev_res, ev_events.</dt>
		1297	<dt>* Avoid using ev_flags and the EVLIST_*-macros, while it is
		1298	maintained by libev, it does not work exactly the same way as in libevent (consider
		1299	it a private API).</dt>
		1300	<dt>* Priorities are not currently supported. Initialising priorities
		1301	will fail and all watchers will have the same priority, even though there
		1302	is an ev_pri field.</dt>
		1303	<dt>* Other members are not supported.</dt>
		1304	<dt>* The libev emulation is <i>not</i> ABI compatible to libevent, you need
		1305	to use the libev header file and library.</dt>
		1306	</dl>
		1307
		1308	</div>
		1309	<h1 id="C_SUPPORT">C++ SUPPORT</h1><p><a href="#TOP" class="toplink">Top</a></p>
		1310	<div id="C_SUPPORT_CONTENT">
		1311	<p>Libev comes with some simplistic wrapper classes for C++ that mainly allow
		1312	you to use some convinience methods to start/stop watchers and also change
		1313	the callback model to a model using method callbacks on objects.</p>
		1314	<p>To use it,</p>
		1315	<pre> #include <ev++.h>
		1316
		1317	</pre>
		1318	<p>(it is not installed by default). This automatically includes <cite>ev.h</cite>
		1319	and puts all of its definitions (many of them macros) into the global
		1320	namespace. All C++ specific things are put into the <code>ev</code> namespace.</p>
		1321	<p>It should support all the same embedding options as <cite>ev.h</cite>, most notably
		1322	<code>EV_MULTIPLICITY</code>.</p>
		1323	<p>Here is a list of things available in the <code>ev</code> namespace:</p>
		1324	<dl>
		1325	<dt><code>ev::READ</code>, <code>ev::WRITE</code> etc.</dt>
		1326	<dd>
		1327	<p>These are just enum values with the same values as the <code>EV_READ</code> etc.
		1328	macros from <cite>ev.h</cite>.</p>
		1329	</dd>
		1330	<dt><code>ev::tstamp</code>, <code>ev::now</code></dt>
		1331	<dd>
		1332	<p>Aliases to the same types/functions as with the <code>ev_</code> prefix.</p>
		1333	</dd>
		1334	<dt><code>ev::io</code>, <code>ev::timer</code>, <code>ev::periodic</code>, <code>ev::idle</code>, <code>ev::sig</code> etc.</dt>
		1335	<dd>
		1336	<p>For each <code>ev_TYPE</code> watcher in <cite>ev.h</cite> there is a corresponding class of
		1337	the same name in the <code>ev</code> namespace, with the exception of <code>ev_signal</code>
		1338	which is called <code>ev::sig</code> to avoid clashes with the <code>signal</code> macro
		1339	defines by many implementations.</p>
		1340	<p>All of those classes have these methods:</p>
		1341	<p>
		1342	<dl>
		1343	<dt>ev::TYPE::TYPE (object , object::method )</dt>
		1344	<dt>ev::TYPE::TYPE (object , object::method , struct ev_loop *)</dt>
		1345	<dt>ev::TYPE::~TYPE</dt>
		1346	<dd>
		1347	<p>The constructor takes a pointer to an object and a method pointer to
		1348	the event handler callback to call in this class. The constructor calls
		1349	<code>ev_init</code> for you, which means you have to call the <code>set</code> method
		1350	before starting it. If you do not specify a loop then the constructor
		1351	automatically associates the default loop with this watcher.</p>
		1352	<p>The destructor automatically stops the watcher if it is active.</p>
		1353	</dd>
		1354	<dt>w->set (struct ev_loop *)</dt>
		1355	<dd>
		1356	<p>Associates a different <code>struct ev_loop</code> with this watcher. You can only
		1357	do this when the watcher is inactive (and not pending either).</p>
		1358	</dd>
		1359	<dt>w->set ([args])</dt>
		1360	<dd>
		1361	<p>Basically the same as <code>ev_TYPE_set</code>, with the same args. Must be
		1362	called at least once. Unlike the C counterpart, an active watcher gets
		1363	automatically stopped and restarted.</p>
		1364	</dd>
		1365	<dt>w->start ()</dt>
		1366	<dd>
		1367	<p>Starts the watcher. Note that there is no <code>loop</code> argument as the
		1368	constructor already takes the loop.</p>
		1369	</dd>
		1370	<dt>w->stop ()</dt>
		1371	<dd>
		1372	<p>Stops the watcher if it is active. Again, no <code>loop</code> argument.</p>
		1373	</dd>
		1374	<dt>w->again () <code>ev::timer</code>, <code>ev::periodic</code> only</dt>
		1375	<dd>
		1376	<p>For <code>ev::timer</code> and <code>ev::periodic</code>, this invokes the corresponding
		1377	<code>ev_TYPE_again</code> function.</p>
		1378	</dd>
		1379	<dt>w->sweep () <code>ev::embed</code> only</dt>
		1380	<dd>
		1381	<p>Invokes <code>ev_embed_sweep</code>.</p>
		1382	</dd>
		1383	</dl>
		1384	</p>
		1385	</dd>
		1386	</dl>
		1387	<p>Example: Define a class with an IO and idle watcher, start one of them in
		1388	the constructor.</p>
		1389	<pre> class myclass
		1390	{
		1391	ev_io io; void io_cb (ev::io &w, int revents);
		1392	ev_idle idle void idle_cb (ev::idle &w, int revents);
		1393
		1394	myclass ();
		1395	}
		1396
		1397	myclass::myclass (int fd)
		1398	: io (this, &myclass::io_cb),
		1399	idle (this, &myclass::idle_cb)
		1400	{
		1401	io.start (fd, ev::READ);
		1402	}
		1403
		1404	</pre>
713		1405
714	</div>	1406	</div>
715	<h1 id="AUTHOR">AUTHOR</h1><p><a href="#TOP" class="toplink">Top</a></p>	1407	<h1 id="AUTHOR">AUTHOR</h1><p><a href="#TOP" class="toplink">Top</a></p>
716	<div id="AUTHOR_CONTENT">	1408	<div id="AUTHOR_CONTENT">
717	<p>Marc Lehmann <libev@schmorp.de>.</p>	1409	<p>Marc Lehmann <libev@schmorp.de>.</p>

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Revision 1.39 by root, Sat Nov 24 09:48:38 2007 UTC