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

Comparing libev/ev.pod (file contents):
Revision 1.69 by root, Fri Dec 7 19:15:39 2007 UTC vs.
Revision 1.75 by root, Sat Dec 8 14:27:39 2007 UTC

…		…
736	=item bool ev_is_pending (ev_TYPE *watcher)	736	=item bool ev_is_pending (ev_TYPE *watcher)
737		737
738	Returns a true value iff the watcher is pending, (i.e. it has outstanding	738	Returns a true value iff the watcher is pending, (i.e. it has outstanding
739	events but its callback has not yet been invoked). As long as a watcher	739	events but its callback has not yet been invoked). As long as a watcher
740	is pending (but not active) you must not call an init function on it (but	740	is pending (but not active) you must not call an init function on it (but
741	C<ev_TYPE_set> is safe) and you must make sure the watcher is available to	741	C<ev_TYPE_set> is safe), you must not change its priority, and you must
742	libev (e.g. you cnanot C<free ()> it).	742	make sure the watcher is available to libev (e.g. you cannot C<free ()>
		743	it).
743		744
744	=item callback ev_cb (ev_TYPE *watcher)	745	=item callback ev_cb (ev_TYPE *watcher)
745		746
746	Returns the callback currently set on the watcher.	747	Returns the callback currently set on the watcher.
747		748
…		…
766	watchers on the same event and make sure one is called first.	767	watchers on the same event and make sure one is called first.
767		768
768	If you need to suppress invocation when higher priority events are pending	769	If you need to suppress invocation when higher priority events are pending
769	you need to look at C<ev_idle> watchers, which provide this functionality.	770	you need to look at C<ev_idle> watchers, which provide this functionality.
770		771
		772	You I<must not> change the priority of a watcher as long as it is active or
		773	pending.
		774
771	The default priority used by watchers when no priority has been set is	775	The default priority used by watchers when no priority has been set is
772	always C<0>, which is supposed to not be too high and not be too low :).	776	always C<0>, which is supposed to not be too high and not be too low :).
773		777
774	Setting a priority outside the range of C<EV_MINPRI> to C<EV_MAXPRI> is	778	Setting a priority outside the range of C<EV_MINPRI> to C<EV_MAXPRI> is
775	fine, as long as you do not mind that the priority value you query might	779	fine, as long as you do not mind that the priority value you query might
776	or might not have been adjusted to be within valid range.	780	or might not have been adjusted to be within valid range.
		781
		782	=item ev_invoke (loop, ev_TYPE *watcher, int revents)
		783
		784	Invoke the C<watcher> with the given C<loop> and C<revents>. Neither
		785	C<loop> nor C<revents> need to be valid as long as the watcher callback
		786	can deal with that fact.
		787
		788	=item int ev_clear_pending (loop, ev_TYPE *watcher)
		789
		790	If the watcher is pending, this function returns clears its pending status
		791	and returns its C<revents> bitset (as if its callback was invoked). If the
		792	watcher isn't pending it does nothing and returns C<0>.
777		793
778	=back	794	=back
779		795
780		796
781	=head2 ASSOCIATING CUSTOM DATA WITH A WATCHER	797	=head2 ASSOCIATING CUSTOM DATA WITH A WATCHER
…		…
1744		1760
1745	To use it,	1761	To use it,
1746		1762
1747	#include <ev++.h>	1763	#include <ev++.h>
1748		1764
1749	(it is not installed by default). This automatically includes F<ev.h>	1765	This automatically includes F<ev.h> and puts all of its definitions (many
1750	and puts all of its definitions (many of them macros) into the global	1766	of them macros) into the global namespace. All C++ specific things are
1751	namespace. All C++ specific things are put into the C<ev> namespace.	1767	put into the C<ev> namespace. It should support all the same embedding
		1768	options as F<ev.h>, most notably C<EV_MULTIPLICITY>.
1752		1769
1753	It should support all the same embedding options as F<ev.h>, most notably	1770	Care has been taken to keep the overhead low. The only data member the C++
1754	C<EV_MULTIPLICITY>.	1771	classes add (compared to plain C-style watchers) is the event loop pointer
		1772	that the watcher is associated with (or no additional members at all if
		1773	you disable C<EV_MULTIPLICITY> when embedding libev).
		1774
		1775	Currently, functions, and static and non-static member functions can be
		1776	used as callbacks. Other types should be easy to add as long as they only
		1777	need one additional pointer for context. If you need support for other
		1778	types of functors please contact the author (preferably after implementing
		1779	it).
1755		1780
1756	Here is a list of things available in the C<ev> namespace:	1781	Here is a list of things available in the C<ev> namespace:
1757		1782
1758	=over 4	1783	=over 4
1759		1784
…		…
1775		1800
1776	All of those classes have these methods:	1801	All of those classes have these methods:
1777		1802
1778	=over 4	1803	=over 4
1779		1804
1780	=item ev::TYPE::TYPE (object , object::method )	1805	=item ev::TYPE::TYPE ()
1781		1806
1782	=item ev::TYPE::TYPE (object , object::method , struct ev_loop *)	1807	=item ev::TYPE::TYPE (struct ev_loop *)
1783		1808
1784	=item ev::TYPE::~TYPE	1809	=item ev::TYPE::~TYPE
1785		1810
1786	The constructor takes a pointer to an object and a method pointer to	1811	The constructor (optionally) takes an event loop to associate the watcher
1787	the event handler callback to call in this class. The constructor calls	1812	with. If it is omitted, it will use C<EV_DEFAULT>.
1788	C<ev_init> for you, which means you have to call the C<set> method	1813
1789	before starting it. If you do not specify a loop then the constructor	1814	The constructor calls C<ev_init> for you, which means you have to call the
1790	automatically associates the default loop with this watcher.	1815	C<set> method before starting it.
		1816
		1817	It will not set a callback, however: You have to call the templated C<set>
		1818	method to set a callback before you can start the watcher.
		1819
		1820	(The reason why you have to use a method is a limitation in C++ which does
		1821	not allow explicit template arguments for constructors).
1791		1822
1792	The destructor automatically stops the watcher if it is active.	1823	The destructor automatically stops the watcher if it is active.
		1824
		1825	=item w->set<class, &class::method> (object *)
		1826
		1827	This method sets the callback method to call. The method has to have a
		1828	signature of C<void (*)(ev_TYPE &, int)>, it receives the watcher as
		1829	first argument and the C<revents> as second. The object must be given as
		1830	parameter and is stored in the C<data> member of the watcher.
		1831
		1832	This method synthesizes efficient thunking code to call your method from
		1833	the C callback that libev requires. If your compiler can inline your
		1834	callback (i.e. it is visible to it at the place of the C<set> call and
		1835	your compiler is good :), then the method will be fully inlined into the
		1836	thunking function, making it as fast as a direct C callback.
		1837
		1838	Example: simple class declaration and watcher initialisation
		1839
		1840	struct myclass
		1841	{
		1842	void io_cb (ev::io &w, int revents) { }
		1843	}
		1844
		1845	myclass obj;
		1846	ev::io iow;
		1847	iow.set <myclass, &myclass::io_cb> (&obj);
		1848
		1849	=item w->set<function> (void *data = 0)
		1850
		1851	Also sets a callback, but uses a static method or plain function as
		1852	callback. The optional C<data> argument will be stored in the watcher's
		1853	C<data> member and is free for you to use.
		1854
		1855	The prototype of the C<function> must be C<void (*)(ev::TYPE &w, int)>.
		1856
		1857	See the method-C<set> above for more details.
		1858
		1859	Example:
		1860
		1861	static void io_cb (ev::io &w, int revents) { }
		1862	iow.set <io_cb> ();
1793		1863
1794	=item w->set (struct ev_loop *)	1864	=item w->set (struct ev_loop *)
1795		1865
1796	Associates a different C<struct ev_loop> with this watcher. You can only	1866	Associates a different C<struct ev_loop> with this watcher. You can only
1797	do this when the watcher is inactive (and not pending either).	1867	do this when the watcher is inactive (and not pending either).
1798		1868
1799	=item w->set ([args])	1869	=item w->set ([args])
1800		1870
1801	Basically the same as C<ev_TYPE_set>, with the same args. Must be	1871	Basically the same as C<ev_TYPE_set>, with the same args. Must be
1802	called at least once. Unlike the C counterpart, an active watcher gets	1872	called at least once. Unlike the C counterpart, an active watcher gets
1803	automatically stopped and restarted.	1873	automatically stopped and restarted when reconfiguring it with this
		1874	method.
1804		1875
1805	=item w->start ()	1876	=item w->start ()
1806		1877
1807	Starts the watcher. Note that there is no C<loop> argument as the	1878	Starts the watcher. Note that there is no C<loop> argument, as the
1808	constructor already takes the loop.	1879	constructor already stores the event loop.
1809		1880
1810	=item w->stop ()	1881	=item w->stop ()
1811		1882
1812	Stops the watcher if it is active. Again, no C<loop> argument.	1883	Stops the watcher if it is active. Again, no C<loop> argument.
1813		1884
…		…
1838		1909
1839	myclass ();	1910	myclass ();
1840	}	1911	}
1841		1912
1842	myclass::myclass (int fd)	1913	myclass::myclass (int fd)
1843	: io (this, &myclass::io_cb),
1844	idle (this, &myclass::idle_cb)
1845	{	1914	{
		1915	io .set <myclass, &myclass::io_cb > (this);
		1916	idle.set <myclass, &myclass::idle_cb> (this);
		1917
1846	io.start (fd, ev::READ);	1918	io.start (fd, ev::READ);
1847	}	1919	}
1848		1920
1849		1921
1850	=head1 MACRO MAGIC	1922	=head1 MACRO MAGIC
…		…
2255		2327
2256	In this section the complexities of (many of) the algorithms used inside	2328	In this section the complexities of (many of) the algorithms used inside
2257	libev will be explained. For complexity discussions about backends see the	2329	libev will be explained. For complexity discussions about backends see the
2258	documentation for C<ev_default_init>.	2330	documentation for C<ev_default_init>.
2259		2331
		2332	All of the following are about amortised time: If an array needs to be
		2333	extended, libev needs to realloc and move the whole array, but this
		2334	happens asymptotically never with higher number of elements, so O(1) might
		2335	mean it might do a lengthy realloc operation in rare cases, but on average
		2336	it is much faster and asymptotically approaches constant time.
		2337
2260	=over 4	2338	=over 4
2261		2339
2262	=item Starting and stopping timer/periodic watchers: O(log skipped_other_timers)	2340	=item Starting and stopping timer/periodic watchers: O(log skipped_other_timers)
2263		2341
2264	This means that, when you have a watcher that triggers in one hour and	2342	This means that, when you have a watcher that triggers in one hour and
…		…
2270	That means that for changing a timer costs less than removing/adding them	2348	That means that for changing a timer costs less than removing/adding them
2271	as only the relative motion in the event queue has to be paid for.	2349	as only the relative motion in the event queue has to be paid for.
2272		2350
2273	=item Starting io/check/prepare/idle/signal/child watchers: O(1)	2351	=item Starting io/check/prepare/idle/signal/child watchers: O(1)
2274		2352
2275	These just add the watcher into an array or at the head of a list. If	2353	These just add the watcher into an array or at the head of a list.
2276	the array needs to be extended libev needs to realloc and move the whole
2277	array, but this happen asymptotically less and less with more watchers,
2278	thus amortised O(1).
2279
2280	=item Stopping check/prepare/idle watchers: O(1)	2354	=item Stopping check/prepare/idle watchers: O(1)
2281		2355
2282	=item Stopping an io/signal/child watcher: O(number_of_watchers_for_this_(fd/signal/pid % EV_PID_HASHSIZE))	2356	=item Stopping an io/signal/child watcher: O(number_of_watchers_for_this_(fd/signal/pid % EV_PID_HASHSIZE))
2283		2357
2284	These watchers are stored in lists then need to be walked to find the	2358	These watchers are stored in lists then need to be walked to find the

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Comparing libev/ev.pod (file contents): Revision 1.69 by root, Fri Dec 7 19:15:39 2007 UTC vs. Revision 1.75 by root, Sat Dec 8 14:27:39 2007 UTC

Diff Legend

Comparing libev/ev.pod (file contents):
Revision 1.69 by root, Fri Dec 7 19:15:39 2007 UTC vs.
Revision 1.75 by root, Sat Dec 8 14:27:39 2007 UTC