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

Comparing libev/ev.pod (file contents):
Revision 1.35 by root, Fri Nov 23 19:35:09 2007 UTC vs.
Revision 1.39 by root, Sat Nov 24 10:10:26 2007 UTC

…		…
323	fatal ("no epoll found here, maybe it hides under your chair");	323	fatal ("no epoll found here, maybe it hides under your chair");
324		324
325	=item ev_default_destroy ()	325	=item ev_default_destroy ()
326		326
327	Destroys the default loop again (frees all memory and kernel state	327	Destroys the default loop again (frees all memory and kernel state
328	etc.). This stops all registered event watchers (by not touching them in	328	etc.). None of the active event watchers will be stopped in the normal
329	any way whatsoever, although you cannot rely on this :).	329	sense, so e.g. C<ev_is_active> might still return true. It is your
		330	responsibility to either stop all watchers cleanly yoursef I<before>
		331	calling this function, or cope with the fact afterwards (which is usually
		332	the easiest thing, youc na just ignore the watchers and/or C<free ()> them
		333	for example).
330		334
331	=item ev_loop_destroy (loop)	335	=item ev_loop_destroy (loop)
332		336
333	Like C<ev_default_destroy>, but destroys an event loop created by an	337	Like C<ev_default_destroy>, but destroys an event loop created by an
334	earlier call to C<ev_loop_new>.	338	earlier call to C<ev_loop_new>.
…		…
505	*) >>), and you can stop watching for events at any time by calling the	509	*) >>), and you can stop watching for events at any time by calling the
506	corresponding stop function (C<< ev_<type>_stop (loop, watcher *) >>.	510	corresponding stop function (C<< ev_<type>_stop (loop, watcher *) >>.
507		511
508	As long as your watcher is active (has been started but not stopped) you	512	As long as your watcher is active (has been started but not stopped) you
509	must not touch the values stored in it. Most specifically you must never	513	must not touch the values stored in it. Most specifically you must never
510	reinitialise it or call its set macro.	514	reinitialise it or call its C<set> macro.
511
512	You can check whether an event is active by calling the C<ev_is_active
513	(watcher *)> macro. To see whether an event is outstanding (but the
514	callback for it has not been called yet) you can use the C<ev_is_pending
515	(watcher *)> macro.
516		515
517	Each and every callback receives the event loop pointer as first, the	516	Each and every callback receives the event loop pointer as first, the
518	registered watcher structure as second, and a bitset of received events as	517	registered watcher structure as second, and a bitset of received events as
519	third argument.	518	third argument.
520		519
…		…
576	your callbacks is well-written it can just attempt the operation and cope	575	your callbacks is well-written it can just attempt the operation and cope
577	with the error from read() or write(). This will not work in multithreaded	576	with the error from read() or write(). This will not work in multithreaded
578	programs, though, so beware.	577	programs, though, so beware.
579		578
580	=back	579	=back
		580
		581	=head2 SUMMARY OF GENERIC WATCHER FUNCTIONS
		582
		583	In the following description, C<TYPE> stands for the watcher type,
		584	e.g. C<timer> for C<ev_timer> watchers and C<io> for C<ev_io> watchers.
		585
		586	=over 4
		587
		588	=item C<ev_init> (ev_TYPE *watcher, callback)
		589
		590	This macro initialises the generic portion of a watcher. The contents
		591	of the watcher object can be arbitrary (so C<malloc> will do). Only
		592	the generic parts of the watcher are initialised, you I<need> to call
		593	the type-specific C<ev_TYPE_set> macro afterwards to initialise the
		594	type-specific parts. For each type there is also a C<ev_TYPE_init> macro
		595	which rolls both calls into one.
		596
		597	You can reinitialise a watcher at any time as long as it has been stopped
		598	(or never started) and there are no pending events outstanding.
		599
		600	The callbakc is always of type C<void ()(ev_loop loop, ev_TYPE *watcher,
		601	int revents)>.
		602
		603	=item C<ev_TYPE_set> (ev_TYPE *, [args])
		604
		605	This macro initialises the type-specific parts of a watcher. You need to
		606	call C<ev_init> at least once before you call this macro, but you can
		607	call C<ev_TYPE_set> any number of times. You must not, however, call this
		608	macro on a watcher that is active (it can be pending, however, which is a
		609	difference to the C<ev_init> macro).
		610
		611	Although some watcher types do not have type-specific arguments
		612	(e.g. C<ev_prepare>) you still need to call its C<set> macro.
		613
		614	=item C<ev_TYPE_init> (ev_TYPE *watcher, callback, [args])
		615
		616	This convinience macro rolls both C<ev_init> and C<ev_TYPE_set> macro
		617	calls into a single call. This is the most convinient method to initialise
		618	a watcher. The same limitations apply, of course.
		619
		620	=item C<ev_TYPE_start> (loop , ev_TYPE watcher)
		621
		622	Starts (activates) the given watcher. Only active watchers will receive
		623	events. If the watcher is already active nothing will happen.
		624
		625	=item C<ev_TYPE_stop> (loop , ev_TYPE watcher)
		626
		627	Stops the given watcher again (if active) and clears the pending
		628	status. It is possible that stopped watchers are pending (for example,
		629	non-repeating timers are being stopped when they become pending), but
		630	C<ev_TYPE_stop> ensures that the watcher is neither active nor pending. If
		631	you want to free or reuse the memory used by the watcher it is therefore a
		632	good idea to always call its C<ev_TYPE_stop> function.
		633
		634	=item bool ev_is_active (ev_TYPE *watcher)
		635
		636	Returns a true value iff the watcher is active (i.e. it has been started
		637	and not yet been stopped). As long as a watcher is active you must not modify
		638	it.
		639
		640	=item bool ev_is_pending (ev_TYPE *watcher)
		641
		642	Returns a true value iff the watcher is pending, (i.e. it has outstanding
		643	events but its callback has not yet been invoked). As long as a watcher
		644	is pending (but not active) you must not call an init function on it (but
		645	C<ev_TYPE_set> is safe) and you must make sure the watcher is available to
		646	libev (e.g. you cnanot C<free ()> it).
		647
		648	=item callback = ev_cb (ev_TYPE *watcher)
		649
		650	Returns the callback currently set on the watcher.
		651
		652	=item ev_cb_set (ev_TYPE *watcher, callback)
		653
		654	Change the callback. You can change the callback at virtually any time
		655	(modulo threads).
		656
		657	=back
		658
581		659
582	=head2 ASSOCIATING CUSTOM DATA WITH A WATCHER	660	=head2 ASSOCIATING CUSTOM DATA WITH A WATCHER
583		661
584	Each watcher has, by default, a member C<void *data> that you can change	662	Each watcher has, by default, a member C<void *data> that you can change
585	and read at any time, libev will completely ignore it. This can be used	663	and read at any time, libev will completely ignore it. This can be used
…		…
778	(and unfortunately a bit complex).	856	(and unfortunately a bit complex).
779		857
780	Unlike C<ev_timer>'s, they are not based on real time (or relative time)	858	Unlike C<ev_timer>'s, they are not based on real time (or relative time)
781	but on wallclock time (absolute time). You can tell a periodic watcher	859	but on wallclock time (absolute time). You can tell a periodic watcher
782	to trigger "at" some specific point in time. For example, if you tell a	860	to trigger "at" some specific point in time. For example, if you tell a
783	periodic watcher to trigger in 10 seconds (by specifiying e.g. c<ev_now ()	861	periodic watcher to trigger in 10 seconds (by specifiying e.g. C<ev_now ()
784	+ 10.>) and then reset your system clock to the last year, then it will	862	+ 10.>) and then reset your system clock to the last year, then it will
785	take a year to trigger the event (unlike an C<ev_timer>, which would trigger	863	take a year to trigger the event (unlike an C<ev_timer>, which would trigger
786	roughly 10 seconds later and of course not if you reset your system time	864	roughly 10 seconds later and of course not if you reset your system time
787	again).	865	again).
788		866
…		…
1058		1136
1059		1137
1060	=head2 C<ev_embed> - when one backend isn't enough	1138	=head2 C<ev_embed> - when one backend isn't enough
1061		1139
1062	This is a rather advanced watcher type that lets you embed one event loop	1140	This is a rather advanced watcher type that lets you embed one event loop
1063	into another.	1141	into another (currently only C<ev_io> events are supported in the embedded
		1142	loop, other types of watchers might be handled in a delayed or incorrect
		1143	fashion and must not be used).
1064		1144
1065	There are primarily two reasons you would want that: work around bugs and	1145	There are primarily two reasons you would want that: work around bugs and
1066	prioritise I/O.	1146	prioritise I/O.
1067		1147
1068	As an example for a bug workaround, the kqueue backend might only support	1148	As an example for a bug workaround, the kqueue backend might only support
…		…
1076	As for prioritising I/O: rarely you have the case where some fds have	1156	As for prioritising I/O: rarely you have the case where some fds have
1077	to be watched and handled very quickly (with low latency), and even	1157	to be watched and handled very quickly (with low latency), and even
1078	priorities and idle watchers might have too much overhead. In this case	1158	priorities and idle watchers might have too much overhead. In this case
1079	you would put all the high priority stuff in one loop and all the rest in	1159	you would put all the high priority stuff in one loop and all the rest in
1080	a second one, and embed the second one in the first.	1160	a second one, and embed the second one in the first.
		1161
		1162	As long as the watcher is active, the callback will be invoked every time
		1163	there might be events pending in the embedded loop. The callback must then
		1164	call C<ev_embed_sweep (mainloop, watcher)> to make a single sweep and invoke
		1165	their callbacks (you could also start an idle watcher to give the embedded
		1166	loop strictly lower priority for example). You can also set the callback
		1167	to C<0>, in which case the embed watcher will automatically execute the
		1168	embedded loop sweep.
1081		1169
1082	As long as the watcher is started it will automatically handle events. The	1170	As long as the watcher is started it will automatically handle events. The
1083	callback will be invoked whenever some events have been handled. You can	1171	callback will be invoked whenever some events have been handled. You can
1084	set the callback to C<0> to avoid having to specify one if you are not	1172	set the callback to C<0> to avoid having to specify one if you are not
1085	interested in that.	1173	interested in that.
…		…
1117	else	1205	else
1118	loop_lo = loop_hi;	1206	loop_lo = loop_hi;
1119		1207
1120	=over 4	1208	=over 4
1121		1209
1122	=item ev_embed_init (ev_embed , callback, struct ev_loop loop)	1210	=item ev_embed_init (ev_embed , callback, struct ev_loop embedded_loop)
1123		1211
1124	=item ev_embed_set (ev_embed , callback, struct ev_loop loop)	1212	=item ev_embed_set (ev_embed , callback, struct ev_loop embedded_loop)
1125		1213
1126	Configures the watcher to embed the given loop, which must be embeddable.	1214	Configures the watcher to embed the given loop, which must be
		1215	embeddable. If the callback is C<0>, then C<ev_embed_sweep> will be
		1216	invoked automatically, otherwise it is the responsibility of the callback
		1217	to invoke it (it will continue to be called until the sweep has been done,
		1218	if you do not want thta, you need to temporarily stop the embed watcher).
		1219
		1220	=item ev_embed_sweep (loop, ev_embed *)
		1221
		1222	Make a single, non-blocking sweep over the embedded loop. This works
		1223	similarly to C<ev_loop (embedded_loop, EVLOOP_NONBLOCK)>, but in the most
		1224	apropriate way for embedded loops.
1127		1225
1128	=back	1226	=back
1129		1227
1130		1228
1131	=head1 OTHER FUNCTIONS	1229	=head1 OTHER FUNCTIONS
…		…
1164	/* stdin might have data for us, joy! */;	1262	/* stdin might have data for us, joy! */;
1165	}	1263	}
1166		1264
1167	ev_once (STDIN_FILENO, EV_READ, 10., stdin_ready, 0);	1265	ev_once (STDIN_FILENO, EV_READ, 10., stdin_ready, 0);
1168		1266
1169	=item ev_feed_event (loop, watcher, int events)	1267	=item ev_feed_event (ev_loop , watcher , int revents)
1170		1268
1171	Feeds the given event set into the event loop, as if the specified event	1269	Feeds the given event set into the event loop, as if the specified event
1172	had happened for the specified watcher (which must be a pointer to an	1270	had happened for the specified watcher (which must be a pointer to an
1173	initialised but not necessarily started event watcher).	1271	initialised but not necessarily started event watcher).
1174		1272
1175	=item ev_feed_fd_event (loop, int fd, int revents)	1273	=item ev_feed_fd_event (ev_loop *, int fd, int revents)
1176		1274
1177	Feed an event on the given fd, as if a file descriptor backend detected	1275	Feed an event on the given fd, as if a file descriptor backend detected
1178	the given events it.	1276	the given events it.
1179		1277
1180	=item ev_feed_signal_event (loop, int signum)	1278	=item ev_feed_signal_event (ev_loop *loop, int signum)
1181		1279
1182	Feed an event as if the given signal occured (loop must be the default loop!).	1280	Feed an event as if the given signal occured (C<loop> must be the default
		1281	loop!).
1183		1282
1184	=back	1283	=back
1185		1284
1186		1285
1187	=head1 LIBEVENT EMULATION	1286	=head1 LIBEVENT EMULATION
…		…
1211		1310
1212	=back	1311	=back
1213		1312
1214	=head1 C++ SUPPORT	1313	=head1 C++ SUPPORT
1215		1314
1216	TBD.	1315	Libev comes with some simplistic wrapper classes for C++ that mainly allow
		1316	you to use some convinience methods to start/stop watchers and also change
		1317	the callback model to a model using method callbacks on objects.
		1318
		1319	To use it,
		1320
		1321	#include <ev++.h>
		1322
		1323	(it is not installed by default). This automatically includes F<ev.h>
		1324	and puts all of its definitions (many of them macros) into the global
		1325	namespace. All C++ specific things are put into the C<ev> namespace.
		1326
		1327	It should support all the same embedding options as F<ev.h>, most notably
		1328	C<EV_MULTIPLICITY>.
		1329
		1330	Here is a list of things available in the C<ev> namespace:
		1331
		1332	=over 4
		1333
		1334	=item C<ev::READ>, C<ev::WRITE> etc.
		1335
		1336	These are just enum values with the same values as the C<EV_READ> etc.
		1337	macros from F<ev.h>.
		1338
		1339	=item C<ev::tstamp>, C<ev::now>
		1340
		1341	Aliases to the same types/functions as with the C<ev_> prefix.
		1342
		1343	=item C<ev::io>, C<ev::timer>, C<ev::periodic>, C<ev::idle>, C<ev::sig> etc.
		1344
		1345	For each C<ev_TYPE> watcher in F<ev.h> there is a corresponding class of
		1346	the same name in the C<ev> namespace, with the exception of C<ev_signal>
		1347	which is called C<ev::sig> to avoid clashes with the C<signal> macro
		1348	defines by many implementations.
		1349
		1350	All of those classes have these methods:
		1351
		1352	=over 4
		1353
		1354	=item ev::TYPE::TYPE (object , object::method )
		1355
		1356	=item ev::TYPE::TYPE (object , object::method , struct ev_loop *)
		1357
		1358	=item ev::TYPE::~TYPE
		1359
		1360	The constructor takes a pointer to an object and a method pointer to
		1361	the event handler callback to call in this class. The constructor calls
		1362	C<ev_init> for you, which means you have to call the C<set> method
		1363	before starting it. If you do not specify a loop then the constructor
		1364	automatically associates the default loop with this watcher.
		1365
		1366	The destructor automatically stops the watcher if it is active.
		1367
		1368	=item w->set (struct ev_loop *)
		1369
		1370	Associates a different C<struct ev_loop> with this watcher. You can only
		1371	do this when the watcher is inactive (and not pending either).
		1372
		1373	=item w->set ([args])
		1374
		1375	Basically the same as C<ev_TYPE_set>, with the same args. Must be
		1376	called at least once. Unlike the C counterpart, an active watcher gets
		1377	automatically stopped and restarted.
		1378
		1379	=item w->start ()
		1380
		1381	Starts the watcher. Note that there is no C<loop> argument as the
		1382	constructor already takes the loop.
		1383
		1384	=item w->stop ()
		1385
		1386	Stops the watcher if it is active. Again, no C<loop> argument.
		1387
		1388	=item w->again () C<ev::timer>, C<ev::periodic> only
		1389
		1390	For C<ev::timer> and C<ev::periodic>, this invokes the corresponding
		1391	C<ev_TYPE_again> function.
		1392
		1393	=item w->sweep () C<ev::embed> only
		1394
		1395	Invokes C<ev_embed_sweep>.
		1396
		1397	=back
		1398
		1399	=back
		1400
		1401	Example: Define a class with an IO and idle watcher, start one of them in
		1402	the constructor.
		1403
		1404	class myclass
		1405	{
		1406	ev_io io; void io_cb (ev::io &w, int revents);
		1407	ev_idle idle void idle_cb (ev::idle &w, int revents);
		1408
		1409	myclass ();
		1410	}
		1411
		1412	myclass::myclass (int fd)
		1413	: io (this, &myclass::io_cb),
		1414	idle (this, &myclass::idle_cb)
		1415	{
		1416	io.start (fd, ev::READ);
		1417	}
		1418
		1419	=head1 EMBEDDING
		1420
		1421	Libev can (and often is) directly embedded into host
		1422	applications. Examples of applications that embed it include the Deliantra
		1423	Game Server, the EV perl module, the GNU Virtual Private Ethernet (gvpe)
		1424	and rxvt-unicode.
		1425
		1426	The goal is to enable you to just copy the neecssary files into your
		1427	source directory without having to change even a single line in them, so
		1428	you can easily upgrade by simply copying (or having a checked-out copy of
		1429	libev somewhere in your source tree).
		1430
		1431	=head2 FILESETS
		1432
		1433	Depending on what features you need you need to include one or more sets of files
		1434	in your app.
		1435
		1436	=head3 CORE EVENT LOOP
		1437
		1438	To include only the libev core (all the C<ev_*> functions), with manual
		1439	configuration (no autoconf):
		1440
		1441	#define EV_STANDALONE 1
		1442	#include "ev.c"
		1443
		1444	This will automatically include F<ev.h>, too, and should be done in a
		1445	single C source file only to provide the function implementations. To use
		1446	it, do the same for F<ev.h> in all files wishing to use this API (best
		1447	done by writing a wrapper around F<ev.h> that you can include instead and
		1448	where you can put other configuration options):
		1449
		1450	#define EV_STANDALONE 1
		1451	#include "ev.h"
		1452
		1453	Both header files and implementation files can be compiled with a C++
		1454	compiler (at least, thats a stated goal, and breakage will be treated
		1455	as a bug).
		1456
		1457	You need the following files in your source tree, or in a directory
		1458	in your include path (e.g. in libev/ when using -Ilibev):
		1459
		1460	ev.h
		1461	ev.c
		1462	ev_vars.h
		1463	ev_wrap.h
		1464
		1465	ev_win32.c required on win32 platforms only
		1466
		1467	ev_select.c only when select backend is enabled (which is is by default)
		1468	ev_poll.c only when poll backend is enabled (disabled by default)
		1469	ev_epoll.c only when the epoll backend is enabled (disabled by default)
		1470	ev_kqueue.c only when the kqueue backend is enabled (disabled by default)
		1471	ev_port.c only when the solaris port backend is enabled (disabled by default)
		1472
		1473	F<ev.c> includes the backend files directly when enabled, so you only need
		1474	to compile a single file.
		1475
		1476	=head3 LIBEVENT COMPATIBILITY API
		1477
		1478	To include the libevent compatibility API, also include:
		1479
		1480	#include "event.c"
		1481
		1482	in the file including F<ev.c>, and:
		1483
		1484	#include "event.h"
		1485
		1486	in the files that want to use the libevent API. This also includes F<ev.h>.
		1487
		1488	You need the following additional files for this:
		1489
		1490	event.h
		1491	event.c
		1492
		1493	=head3 AUTOCONF SUPPORT
		1494
		1495	Instead of using C<EV_STANDALONE=1> and providing your config in
		1496	whatever way you want, you can also C<m4_include([libev.m4])> in your
		1497	F<configure.ac> and leave C<EV_STANDALONE> off. F<ev.c> will then include
		1498	F<config.h> and configure itself accordingly.
		1499
		1500	For this of course you need the m4 file:
		1501
		1502	libev.m4
		1503
		1504	=head2 PREPROCESSOR SYMBOLS/MACROS
		1505
		1506	Libev can be configured via a variety of preprocessor symbols you have to define
		1507	before including any of its files. The default is not to build for multiplicity
		1508	and only include the select backend.
		1509
		1510	=over 4
		1511
		1512	=item EV_STANDALONE
		1513
		1514	Must always be C<1> if you do not use autoconf configuration, which
		1515	keeps libev from including F<config.h>, and it also defines dummy
		1516	implementations for some libevent functions (such as logging, which is not
		1517	supported). It will also not define any of the structs usually found in
		1518	F<event.h> that are not directly supported by the libev core alone.
		1519
		1520	=item EV_USE_MONOTONIC
		1521
		1522	If defined to be C<1>, libev will try to detect the availability of the
		1523	monotonic clock option at both compiletime and runtime. Otherwise no use
		1524	of the monotonic clock option will be attempted. If you enable this, you
		1525	usually have to link against librt or something similar. Enabling it when
		1526	the functionality isn't available is safe, though, althoguh you have
		1527	to make sure you link against any libraries where the C<clock_gettime>
		1528	function is hiding in (often F<-lrt>).
		1529
		1530	=item EV_USE_REALTIME
		1531
		1532	If defined to be C<1>, libev will try to detect the availability of the
		1533	realtime clock option at compiletime (and assume its availability at
		1534	runtime if successful). Otherwise no use of the realtime clock option will
		1535	be attempted. This effectively replaces C<gettimeofday> by C<clock_get
		1536	(CLOCK_REALTIME, ...)> and will not normally affect correctness. See tzhe note about libraries
		1537	in the description of C<EV_USE_MONOTONIC>, though.
		1538
		1539	=item EV_USE_SELECT
		1540
		1541	If undefined or defined to be C<1>, libev will compile in support for the
		1542	C<select>(2) backend. No attempt at autodetection will be done: if no
		1543	other method takes over, select will be it. Otherwise the select backend
		1544	will not be compiled in.
		1545
		1546	=item EV_SELECT_USE_FD_SET
		1547
		1548	If defined to C<1>, then the select backend will use the system C<fd_set>
		1549	structure. This is useful if libev doesn't compile due to a missing
		1550	C<NFDBITS> or C<fd_mask> definition or it misguesses the bitset layout on
		1551	exotic systems. This usually limits the range of file descriptors to some
		1552	low limit such as 1024 or might have other limitations (winsocket only
		1553	allows 64 sockets). The C<FD_SETSIZE> macro, set before compilation, might
		1554	influence the size of the C<fd_set> used.
		1555
		1556	=item EV_SELECT_IS_WINSOCKET
		1557
		1558	When defined to C<1>, the select backend will assume that
		1559	select/socket/connect etc. don't understand file descriptors but
		1560	wants osf handles on win32 (this is the case when the select to
		1561	be used is the winsock select). This means that it will call
		1562	C<_get_osfhandle> on the fd to convert it to an OS handle. Otherwise,
		1563	it is assumed that all these functions actually work on fds, even
		1564	on win32. Should not be defined on non-win32 platforms.
		1565
		1566	=item EV_USE_POLL
		1567
		1568	If defined to be C<1>, libev will compile in support for the C<poll>(2)
		1569	backend. Otherwise it will be enabled on non-win32 platforms. It
		1570	takes precedence over select.
		1571
		1572	=item EV_USE_EPOLL
		1573
		1574	If defined to be C<1>, libev will compile in support for the Linux
		1575	C<epoll>(7) backend. Its availability will be detected at runtime,
		1576	otherwise another method will be used as fallback. This is the
		1577	preferred backend for GNU/Linux systems.
		1578
		1579	=item EV_USE_KQUEUE
		1580
		1581	If defined to be C<1>, libev will compile in support for the BSD style
		1582	C<kqueue>(2) backend. Its actual availability will be detected at runtime,
		1583	otherwise another method will be used as fallback. This is the preferred
		1584	backend for BSD and BSD-like systems, although on most BSDs kqueue only
		1585	supports some types of fds correctly (the only platform we found that
		1586	supports ptys for example was NetBSD), so kqueue might be compiled in, but
		1587	not be used unless explicitly requested. The best way to use it is to find
		1588	out wether kqueue supports your type of fd properly and use an embedded
		1589	kqueue loop.
		1590
		1591	=item EV_USE_PORT
		1592
		1593	If defined to be C<1>, libev will compile in support for the Solaris
		1594	10 port style backend. Its availability will be detected at runtime,
		1595	otherwise another method will be used as fallback. This is the preferred
		1596	backend for Solaris 10 systems.
		1597
		1598	=item EV_USE_DEVPOLL
		1599
		1600	reserved for future expansion, works like the USE symbols above.
		1601
		1602	=item EV_H
		1603
		1604	The name of the F<ev.h> header file used to include it. The default if
		1605	undefined is C<< <ev.h> >> in F<event.h> and C<"ev.h"> in F<ev.c>. This
		1606	can be used to virtually rename the F<ev.h> header file in case of conflicts.
		1607
		1608	=item EV_CONFIG_H
		1609
		1610	If C<EV_STANDALONE> isn't C<1>, this variable can be used to override
		1611	F<ev.c>'s idea of where to find the F<config.h> file, similarly to
		1612	C<EV_H>, above.
		1613
		1614	=item EV_EVENT_H
		1615
		1616	Similarly to C<EV_H>, this macro can be used to override F<event.c>'s idea
		1617	of how the F<event.h> header can be found.
		1618
		1619	=item EV_PROTOTYPES
		1620
		1621	If defined to be C<0>, then F<ev.h> will not define any function
		1622	prototypes, but still define all the structs and other symbols. This is
		1623	occasionally useful if you want to provide your own wrapper functions
		1624	around libev functions.
		1625
		1626	=item EV_MULTIPLICITY
		1627
		1628	If undefined or defined to C<1>, then all event-loop-specific functions
		1629	will have the C<struct ev_loop *> as first argument, and you can create
		1630	additional independent event loops. Otherwise there will be no support
		1631	for multiple event loops and there is no first event loop pointer
		1632	argument. Instead, all functions act on the single default loop.
		1633
		1634	=item EV_PERIODICS
		1635
		1636	If undefined or defined to be C<1>, then periodic timers are supported,
		1637	otherwise not. This saves a few kb of code.
		1638
		1639	=item EV_COMMON
		1640
		1641	By default, all watchers have a C<void *data> member. By redefining
		1642	this macro to a something else you can include more and other types of
		1643	members. You have to define it each time you include one of the files,
		1644	though, and it must be identical each time.
		1645
		1646	For example, the perl EV module uses something like this:
		1647
		1648	#define EV_COMMON \
		1649	SV self; / contains this struct */ \
		1650	SV cb_sv, fh /* note no trailing ";" */
		1651
		1652	=item EV_CB_DECLARE(type)
		1653
		1654	=item EV_CB_INVOKE(watcher,revents)
		1655
		1656	=item ev_set_cb(ev,cb)
		1657
		1658	Can be used to change the callback member declaration in each watcher,
		1659	and the way callbacks are invoked and set. Must expand to a struct member
		1660	definition and a statement, respectively. See the F<ev.v> header file for
		1661	their default definitions. One possible use for overriding these is to
		1662	avoid the ev_loop pointer as first argument in all cases, or to use method
		1663	calls instead of plain function calls in C++.
		1664
		1665	=head2 EXAMPLES
		1666
		1667	For a real-world example of a program the includes libev
		1668	verbatim, you can have a look at the EV perl module
		1669	(L<http://software.schmorp.de/pkg/EV.html>). It has the libev files in
		1670	the F<libev/> subdirectory and includes them in the F<EV/EVAPI.h> (public
		1671	interface) and F<EV.xs> (implementation) files. Only the F<EV.xs> file
		1672	will be compiled. It is pretty complex because it provides its own header
		1673	file.
		1674
		1675	The usage in rxvt-unicode is simpler. It has a F<ev_cpp.h> header file
		1676	that everybody includes and which overrides some autoconf choices:
		1677
		1678	#define EV_USE_POLL 0
		1679	#define EV_MULTIPLICITY 0
		1680	#define EV_PERIODICS 0
		1681	#define EV_CONFIG_H <config.h>
		1682
		1683	#include "ev++.h"
		1684
		1685	And a F<ev_cpp.C> implementation file that contains libev proper and is compiled:
		1686
		1687	#include "rxvttoolkit.h"
		1688
		1689	/* darwin has problems with its header files in C++, requiring this namespace juggling */
		1690	using namespace ev;
		1691
		1692	#include "ev.c"
		1693
1217		1694
1218	=head1 AUTHOR	1695	=head1 AUTHOR
1219		1696
1220	Marc Lehmann <libev@schmorp.de>.	1697	Marc Lehmann <libev@schmorp.de>.
1221		1698

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Comparing libev/ev.pod (file contents): Revision 1.35 by root, Fri Nov 23 19:35:09 2007 UTC vs. Revision 1.39 by root, Sat Nov 24 10:10:26 2007 UTC

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Revision 1.35 by root, Fri Nov 23 19:35:09 2007 UTC vs.
Revision 1.39 by root, Sat Nov 24 10:10:26 2007 UTC