[ViewVC] Diff of: cvs/Coro/Coro.pm

Comparing Coro/Coro.pm (file contents):
Revision 1.247 by root, Mon Dec 15 02:07:11 2008 UTC vs.
Revision 1.281 by root, Tue Dec 7 17:13:43 2010 UTC

…		…
11	print "2\n";	11	print "2\n";
12	cede; # yield back to main	12	cede; # yield back to main
13	print "4\n";	13	print "4\n";
14	};	14	};
15	print "1\n";	15	print "1\n";
16	cede; # yield to coroutine	16	cede; # yield to coro
17	print "3\n";	17	print "3\n";
18	cede; # and again	18	cede; # and again
19		19
20	# use locking	20	# use locking
21	use Coro::Semaphore;	21	use Coro::Semaphore;
…		…
29	=head1 DESCRIPTION	29	=head1 DESCRIPTION
30		30
31	For a tutorial-style introduction, please read the L<Coro::Intro>	31	For a tutorial-style introduction, please read the L<Coro::Intro>
32	manpage. This manpage mainly contains reference information.	32	manpage. This manpage mainly contains reference information.
33		33
34	This module collection manages continuations in general, most often	34	This module collection manages continuations in general, most often in
35	in the form of cooperative threads (also called coroutines in the	35	the form of cooperative threads (also called coros, or simply "coro"
36	documentation). They are similar to kernel threads but don't (in general)	36	in the documentation). They are similar to kernel threads but don't (in
37	run in parallel at the same time even on SMP machines. The specific flavor	37	general) run in parallel at the same time even on SMP machines. The
38	of thread offered by this module also guarantees you that it will not	38	specific flavor of thread offered by this module also guarantees you that
39	switch between threads unless necessary, at easily-identified points in	39	it will not switch between threads unless necessary, at easily-identified
40	your program, so locking and parallel access are rarely an issue, making	40	points in your program, so locking and parallel access are rarely an
41	thread programming much safer and easier than using other thread models.	41	issue, making thread programming much safer and easier than using other
		42	thread models.
42		43
43	Unlike the so-called "Perl threads" (which are not actually real threads	44	Unlike the so-called "Perl threads" (which are not actually real threads
44	but only the windows process emulation ported to unix), Coro provides a	45	but only the windows process emulation (see section of same name for more
		46	details) ported to unix, and as such act as processes), Coro provides
45	full shared address space, which makes communication between threads	47	a full shared address space, which makes communication between threads
46	very easy. And threads are fast, too: disabling the Windows process	48	very easy. And Coro's threads are fast, too: disabling the Windows
47	emulation code in your perl and using Coro can easily result in a two to	49	process emulation code in your perl and using Coro can easily result in
48	four times speed increase for your programs.	50	a two to four times speed increase for your programs. A parallel matrix
		51	multiplication benchmark runs over 300 times faster on a single core than
		52	perl's pseudo-threads on a quad core using all four cores.
49		53
50	Coro achieves that by supporting multiple running interpreters that share	54	Coro achieves that by supporting multiple running interpreters that share
51	data, which is especially useful to code pseudo-parallel processes and	55	data, which is especially useful to code pseudo-parallel processes and
52	for event-based programming, such as multiple HTTP-GET requests running	56	for event-based programming, such as multiple HTTP-GET requests running
53	concurrently. See L<Coro::AnyEvent> to learn more on how to integrate Coro	57	concurrently. See L<Coro::AnyEvent> to learn more on how to integrate Coro
54	into an event-based environment.	58	into an event-based environment.
55		59
56	In this module, a thread is defined as "callchain + lexical variables +	60	In this module, a thread is defined as "callchain + lexical variables +
57	@_ + $_ + $@ + $/ + C stack), that is, a thread has its own callchain,	61	some package variables + C stack), that is, a thread has its own callchain,
58	its own set of lexicals and its own set of perls most important global	62	its own set of lexicals and its own set of perls most important global
59	variables (see L<Coro::State> for more configuration and background info).	63	variables (see L<Coro::State> for more configuration and background info).
60		64
61	See also the C<SEE ALSO> section at the end of this document - the Coro	65	See also the C<SEE ALSO> section at the end of this document - the Coro
62	module family is quite large.	66	module family is quite large.
63		67
64	=cut	68	=cut
65		69
66	package Coro;	70	package Coro;
67		71
68	use strict qw(vars subs);	72	use common::sense;
69	no warnings "uninitialized";	73
		74	use Carp ();
70		75
71	use Guard ();	76	use Guard ();
72		77
73	use Coro::State;	78	use Coro::State;
74		79
75	use base qw(Coro::State Exporter);	80	use base qw(Coro::State Exporter);
76		81
77	our $idle; # idle handler	82	our $idle; # idle handler
78	our $main; # main coroutine	83	our $main; # main coro
79	our $current; # current coroutine	84	our $current; # current coro
80		85
81	our $VERSION = 5.13;	86	our $VERSION = 5.25;
82		87
83	our @EXPORT = qw(async async_pool cede schedule terminate current unblock_sub);	88	our @EXPORT = qw(async async_pool cede schedule terminate current unblock_sub rouse_cb rouse_wait);
84	our %EXPORT_TAGS = (	89	our %EXPORT_TAGS = (
85	prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],	90	prio => [qw(PRIO_MAX PRIO_HIGH PRIO_NORMAL PRIO_LOW PRIO_IDLE PRIO_MIN)],
86	);	91	);
87	our @EXPORT_OK = (@{$EXPORT_TAGS{prio}}, qw(nready));	92	our @EXPORT_OK = (@{$EXPORT_TAGS{prio}}, qw(nready));
88		93
…		…
90		95
91	=over 4	96	=over 4
92		97
93	=item $Coro::main	98	=item $Coro::main
94		99
95	This variable stores the coroutine object that represents the main	100	This variable stores the Coro object that represents the main
96	program. While you cna C<ready> it and do most other things you can do to	101	program. While you cna C<ready> it and do most other things you can do to
97	coroutines, it is mainly useful to compare again C<$Coro::current>, to see	102	coro, it is mainly useful to compare again C<$Coro::current>, to see
98	whether you are running in the main program or not.	103	whether you are running in the main program or not.
99		104
100	=cut	105	=cut
101		106
102	# $main is now being initialised by Coro::State	107	# $main is now being initialised by Coro::State
103		108
104	=item $Coro::current	109	=item $Coro::current
105		110
106	The coroutine object representing the current coroutine (the last	111	The Coro object representing the current coro (the last
107	coroutine that the Coro scheduler switched to). The initial value is	112	coro that the Coro scheduler switched to). The initial value is
108	C<$Coro::main> (of course).	113	C<$Coro::main> (of course).
109		114
110	This variable is B<strictly> I<read-only>. You can take copies of the	115	This variable is B<strictly> I<read-only>. You can take copies of the
111	value stored in it and use it as any other coroutine object, but you must	116	value stored in it and use it as any other Coro object, but you must
112	not otherwise modify the variable itself.	117	not otherwise modify the variable itself.
113		118
114	=cut	119	=cut
115		120
116	sub current() { $current } # [DEPRECATED]	121	sub current() { $current } # [DEPRECATED]
…		…
119		124
120	This variable is mainly useful to integrate Coro into event loops. It is	125	This variable is mainly useful to integrate Coro into event loops. It is
121	usually better to rely on L<Coro::AnyEvent> or L<Coro::EV>, as this is	126	usually better to rely on L<Coro::AnyEvent> or L<Coro::EV>, as this is
122	pretty low-level functionality.	127	pretty low-level functionality.
123		128
124	This variable stores either a coroutine or a callback.	129	This variable stores a Coro object that is put into the ready queue when
		130	there are no other ready threads (without invoking any ready hooks).
125		131
126	If it is a callback, the it is called whenever the scheduler finds no	132	The default implementation dies with "FATAL: deadlock detected.", followed
127	ready coroutines to run. The default implementation prints "FATAL:	133	by a thread listing, because the program has no other way to continue.
128	deadlock detected" and exits, because the program has no other way to
129	continue.
130
131	If it is a coroutine object, then this object will be readied (without
132	invoking any ready hooks, however) when the scheduler finds no other ready
133	coroutines to run.
134		134
135	This hook is overwritten by modules such as C<Coro::EV> and	135	This hook is overwritten by modules such as C<Coro::EV> and
136	C<Coro::AnyEvent> to wait on an external event that hopefully wake up a	136	C<Coro::AnyEvent> to wait on an external event that hopefully wake up a
137	coroutine so the scheduler can run it.	137	coro so the scheduler can run it.
138		138
139	Note that the callback I<must not>, under any circumstances, block
140	the current coroutine. Normally, this is achieved by having an "idle
141	coroutine" that calls the event loop and then blocks again, and then
142	readying that coroutine in the idle handler, or by simply placing the idle
143	coroutine in this variable.
144
145	See L<Coro::Event> or L<Coro::AnyEvent> for examples of using this	139	See L<Coro::EV> or L<Coro::AnyEvent> for examples of using this technique.
146	technique.
147		140
148	Please note that if your callback recursively invokes perl (e.g. for event
149	handlers), then it must be prepared to be called recursively itself.
150
151	=cut	141	=cut
152		142
153	$idle = sub {	143	# \|\|= because other modules could have provided their own by now
154	require Carp;	144	$idle \|\|= new Coro sub {
155	Carp::croak ("FATAL: deadlock detected");	145	require Coro::Debug;
		146	die "FATAL: deadlock detected.\n"
		147	. Coro::Debug::ps_listing ();
156	};	148	};
157		149
158	# this coroutine is necessary because a coroutine	150	# this coro is necessary because a coro
159	# cannot destroy itself.	151	# cannot destroy itself.
160	our @destroy;	152	our @destroy;
161	our $manager;	153	our $manager;
162		154
163	$manager = new Coro sub {	155	$manager = new Coro sub {
164	while () {	156	while () {
165	Coro::_cancel shift @destroy	157	Coro::State::cancel shift @destroy
166	while @destroy;	158	while @destroy;
167		159
168	&schedule;	160	&schedule;
169	}	161	}
170	};	162	};
171	$manager->{desc} = "[coro manager]";	163	$manager->{desc} = "[coro manager]";
172	$manager->prio (PRIO_MAX);	164	$manager->prio (PRIO_MAX);
173		165
174	=back	166	=back
175		167
176	=head1 SIMPLE COROUTINE CREATION	168	=head1 SIMPLE CORO CREATION
177		169
178	=over 4	170	=over 4
179		171
180	=item async { ... } [@args...]	172	=item async { ... } [@args...]
181		173
182	Create a new coroutine and return its coroutine object (usually	174	Create a new coro and return its Coro object (usually
183	unused). The coroutine will be put into the ready queue, so	175	unused). The coro will be put into the ready queue, so
184	it will start running automatically on the next scheduler run.	176	it will start running automatically on the next scheduler run.
185		177
186	The first argument is a codeblock/closure that should be executed in the	178	The first argument is a codeblock/closure that should be executed in the
187	coroutine. When it returns argument returns the coroutine is automatically	179	coro. When it returns argument returns the coro is automatically
188	terminated.	180	terminated.
189		181
190	The remaining arguments are passed as arguments to the closure.	182	The remaining arguments are passed as arguments to the closure.
191		183
192	See the C<Coro::State::new> constructor for info about the coroutine	184	See the C<Coro::State::new> constructor for info about the coro
193	environment in which coroutines are executed.	185	environment in which coro are executed.
194		186
195	Calling C<exit> in a coroutine will do the same as calling exit outside	187	Calling C<exit> in a coro will do the same as calling exit outside
196	the coroutine. Likewise, when the coroutine dies, the program will exit,	188	the coro. Likewise, when the coro dies, the program will exit,
197	just as it would in the main program.	189	just as it would in the main program.
198		190
199	If you do not want that, you can provide a default C<die> handler, or	191	If you do not want that, you can provide a default C<die> handler, or
200	simply avoid dieing (by use of C<eval>).	192	simply avoid dieing (by use of C<eval>).
201		193
202	Example: Create a new coroutine that just prints its arguments.	194	Example: Create a new coro that just prints its arguments.
203		195
204	async {	196	async {
205	print "@_\n";	197	print "@_\n";
206	} 1,2,3,4;	198	} 1,2,3,4;
207		199
208	=cut
209
210	sub async(&@) {
211	my $coro = new Coro @_;
212	$coro->ready;
213	$coro
214	}
215
216	=item async_pool { ... } [@args...]	200	=item async_pool { ... } [@args...]
217		201
218	Similar to C<async>, but uses a coroutine pool, so you should not call	202	Similar to C<async>, but uses a coro pool, so you should not call
219	terminate or join on it (although you are allowed to), and you get a	203	terminate or join on it (although you are allowed to), and you get a
220	coroutine that might have executed other code already (which can be good	204	coro that might have executed other code already (which can be good
221	or bad :).	205	or bad :).
222		206
223	On the plus side, this function is about twice as fast as creating (and	207	On the plus side, this function is about twice as fast as creating (and
224	destroying) a completely new coroutine, so if you need a lot of generic	208	destroying) a completely new coro, so if you need a lot of generic
225	coroutines in quick successsion, use C<async_pool>, not C<async>.	209	coros in quick successsion, use C<async_pool>, not C<async>.
226		210
227	The code block is executed in an C<eval> context and a warning will be	211	The code block is executed in an C<eval> context and a warning will be
228	issued in case of an exception instead of terminating the program, as	212	issued in case of an exception instead of terminating the program, as
229	C<async> does. As the coroutine is being reused, stuff like C<on_destroy>	213	C<async> does. As the coro is being reused, stuff like C<on_destroy>
230	will not work in the expected way, unless you call terminate or cancel,	214	will not work in the expected way, unless you call terminate or cancel,
231	which somehow defeats the purpose of pooling (but is fine in the	215	which somehow defeats the purpose of pooling (but is fine in the
232	exceptional case).	216	exceptional case).
233		217
234	The priority will be reset to C<0> after each run, tracing will be	218	The priority will be reset to C<0> after each run, tracing will be
235	disabled, the description will be reset and the default output filehandle	219	disabled, the description will be reset and the default output filehandle
236	gets restored, so you can change all these. Otherwise the coroutine will	220	gets restored, so you can change all these. Otherwise the coro will
237	be re-used "as-is": most notably if you change other per-coroutine global	221	be re-used "as-is": most notably if you change other per-coro global
238	stuff such as C<$/> you I<must needs> revert that change, which is most	222	stuff such as C<$/> you I<must needs> revert that change, which is most
239	simply done by using local as in: C<< local $/ >>.	223	simply done by using local as in: C<< local $/ >>.
240		224
241	The idle pool size is limited to C<8> idle coroutines (this can be	225	The idle pool size is limited to C<8> idle coros (this can be
242	adjusted by changing $Coro::POOL_SIZE), but there can be as many non-idle	226	adjusted by changing $Coro::POOL_SIZE), but there can be as many non-idle
243	coros as required.	227	coros as required.
244		228
245	If you are concerned about pooled coroutines growing a lot because a	229	If you are concerned about pooled coros growing a lot because a
246	single C<async_pool> used a lot of stackspace you can e.g. C<async_pool	230	single C<async_pool> used a lot of stackspace you can e.g. C<async_pool
247	{ terminate }> once per second or so to slowly replenish the pool. In	231	{ terminate }> once per second or so to slowly replenish the pool. In
248	addition to that, when the stacks used by a handler grows larger than 32kb	232	addition to that, when the stacks used by a handler grows larger than 32kb
249	(adjustable via $Coro::POOL_RSS) it will also be destroyed.	233	(adjustable via $Coro::POOL_RSS) it will also be destroyed.
250		234
…		…
267	=back	251	=back
268		252
269	=head1 STATIC METHODS	253	=head1 STATIC METHODS
270		254
271	Static methods are actually functions that implicitly operate on the	255	Static methods are actually functions that implicitly operate on the
272	current coroutine.	256	current coro.
273		257
274	=over 4	258	=over 4
275		259
276	=item schedule	260	=item schedule
277		261
278	Calls the scheduler. The scheduler will find the next coroutine that is	262	Calls the scheduler. The scheduler will find the next coro that is
279	to be run from the ready queue and switches to it. The next coroutine	263	to be run from the ready queue and switches to it. The next coro
280	to be run is simply the one with the highest priority that is longest	264	to be run is simply the one with the highest priority that is longest
281	in its ready queue. If there is no coroutine ready, it will clal the	265	in its ready queue. If there is no coro ready, it will call the
282	C<$Coro::idle> hook.	266	C<$Coro::idle> hook.
283		267
284	Please note that the current coroutine will I<not> be put into the ready	268	Please note that the current coro will I<not> be put into the ready
285	queue, so calling this function usually means you will never be called	269	queue, so calling this function usually means you will never be called
286	again unless something else (e.g. an event handler) calls C<< ->ready >>,	270	again unless something else (e.g. an event handler) calls C<< ->ready >>,
287	thus waking you up.	271	thus waking you up.
288		272
289	This makes C<schedule> I<the> generic method to use to block the current	273	This makes C<schedule> I<the> generic method to use to block the current
290	coroutine and wait for events: first you remember the current coroutine in	274	coro and wait for events: first you remember the current coro in
291	a variable, then arrange for some callback of yours to call C<< ->ready	275	a variable, then arrange for some callback of yours to call C<< ->ready
292	>> on that once some event happens, and last you call C<schedule> to put	276	>> on that once some event happens, and last you call C<schedule> to put
293	yourself to sleep. Note that a lot of things can wake your coroutine up,	277	yourself to sleep. Note that a lot of things can wake your coro up,
294	so you need to check whether the event indeed happened, e.g. by storing the	278	so you need to check whether the event indeed happened, e.g. by storing the
295	status in a variable.	279	status in a variable.
296		280
297	See B<HOW TO WAIT FOR A CALLBACK>, below, for some ways to wait for callbacks.	281	See B<HOW TO WAIT FOR A CALLBACK>, below, for some ways to wait for callbacks.
298		282
299	=item cede	283	=item cede
300		284
301	"Cede" to other coroutines. This function puts the current coroutine into	285	"Cede" to other coros. This function puts the current coro into
302	the ready queue and calls C<schedule>, which has the effect of giving	286	the ready queue and calls C<schedule>, which has the effect of giving
303	up the current "timeslice" to other coroutines of the same or higher	287	up the current "timeslice" to other coros of the same or higher
304	priority. Once your coroutine gets its turn again it will automatically be	288	priority. Once your coro gets its turn again it will automatically be
305	resumed.	289	resumed.
306		290
307	This function is often called C<yield> in other languages.	291	This function is often called C<yield> in other languages.
308		292
309	=item Coro::cede_notself	293	=item Coro::cede_notself
310		294
311	Works like cede, but is not exported by default and will cede to I<any>	295	Works like cede, but is not exported by default and will cede to I<any>
312	coroutine, regardless of priority. This is useful sometimes to ensure	296	coro, regardless of priority. This is useful sometimes to ensure
313	progress is made.	297	progress is made.
314		298
315	=item terminate [arg...]	299	=item terminate [arg...]
316		300
317	Terminates the current coroutine with the given status values (see L<cancel>).	301	Terminates the current coro with the given status values (see L<cancel>).
318		302
319	=item Coro::on_enter BLOCK, Coro::on_leave BLOCK	303	=item Coro::on_enter BLOCK, Coro::on_leave BLOCK
320		304
321	These function install enter and leave winders in the current scope. The	305	These function install enter and leave winders in the current scope. The
322	enter block will be executed when on_enter is called and whenever the	306	enter block will be executed when on_enter is called and whenever the
323	current coroutine is re-entered by the scheduler, while the leave block is	307	current coro is re-entered by the scheduler, while the leave block is
324	executed whenever the current coroutine is blocked by the scheduler, and	308	executed whenever the current coro is blocked by the scheduler, and
325	also when the containing scope is exited (by whatever means, be it exit,	309	also when the containing scope is exited (by whatever means, be it exit,
326	die, last etc.).	310	die, last etc.).
327		311
328	I<Neither invoking the scheduler, nor exceptions, are allowed within those	312	I<Neither invoking the scheduler, nor exceptions, are allowed within those
329	BLOCKs>. That means: do not even think about calling C<die> without an	313	BLOCKs>. That means: do not even think about calling C<die> without an
…		…
332	Since both BLOCKs are tied to the current scope, they will automatically	316	Since both BLOCKs are tied to the current scope, they will automatically
333	be removed when the current scope exits.	317	be removed when the current scope exits.
334		318
335	These functions implement the same concept as C<dynamic-wind> in scheme	319	These functions implement the same concept as C<dynamic-wind> in scheme
336	does, and are useful when you want to localise some resource to a specific	320	does, and are useful when you want to localise some resource to a specific
337	coroutine.	321	coro.
338		322
339	They slow down coroutine switching considerably for coroutines that use	323	They slow down thread switching considerably for coros that use them
340	them (But coroutine switching is still reasonably fast if the handlers are	324	(about 40% for a BLOCK with a single assignment, so thread switching is
341	fast).	325	still reasonably fast if the handlers are fast).
342		326
343	These functions are best understood by an example: The following function	327	These functions are best understood by an example: The following function
344	will change the current timezone to "Antarctica/South_Pole", which	328	will change the current timezone to "Antarctica/South_Pole", which
345	requires a call to C<tzset>, but by using C<on_enter> and C<on_leave>,	329	requires a call to C<tzset>, but by using C<on_enter> and C<on_leave>,
346	which remember/change the current timezone and restore the previous	330	which remember/change the current timezone and restore the previous
347	value, respectively, the timezone is only changes for the coroutine that	331	value, respectively, the timezone is only changed for the coro that
348	installed those handlers.	332	installed those handlers.
349		333
350	use POSIX qw(tzset);	334	use POSIX qw(tzset);
351		335
352	async {	336	async {
…		…
363	$ENV{TZ} = $old_tz;	347	$ENV{TZ} = $old_tz;
364	tzset; # restore old value	348	tzset; # restore old value
365	};	349	};
366		350
367	# at this place, the timezone is Antarctica/South_Pole,	351	# at this place, the timezone is Antarctica/South_Pole,
368	# without disturbing the TZ of any other coroutine.	352	# without disturbing the TZ of any other coro.
369	};	353	};
370		354
371	This can be used to localise about any resource (locale, uid, current	355	This can be used to localise about any resource (locale, uid, current
372	working directory etc.) to a block, despite the existance of other	356	working directory etc.) to a block, despite the existance of other
373	coroutines.	357	coros.
		358
		359	Another interesting example implements time-sliced multitasking using
		360	interval timers (this could obviously be optimised, but does the job):
		361
		362	# "timeslice" the given block
		363	sub timeslice(&) {
		364	use Time::HiRes ();
		365
		366	Coro::on_enter {
		367	# on entering the thread, we set an VTALRM handler to cede
		368	$SIG{VTALRM} = sub { cede };
		369	# and then start the interval timer
		370	Time::HiRes::setitimer &Time::HiRes::ITIMER_VIRTUAL, 0.01, 0.01;
		371	};
		372	Coro::on_leave {
		373	# on leaving the thread, we stop the interval timer again
		374	Time::HiRes::setitimer &Time::HiRes::ITIMER_VIRTUAL, 0, 0;
		375	};
		376
		377	&{+shift};
		378	}
		379
		380	# use like this:
		381	timeslice {
		382	# The following is an endless loop that would normally
		383	# monopolise the process. Since it runs in a timesliced
		384	# environment, it will regularly cede to other threads.
		385	while () { }
		386	};
		387
374		388
375	=item killall	389	=item killall
376		390
377	Kills/terminates/cancels all coroutines except the currently running one.	391	Kills/terminates/cancels all coros except the currently running one.
378		392
379	Note that while this will try to free some of the main interpreter	393	Note that while this will try to free some of the main interpreter
380	resources if the calling coroutine isn't the main coroutine, but one	394	resources if the calling coro isn't the main coro, but one
381	cannot free all of them, so if a coroutine that is not the main coroutine	395	cannot free all of them, so if a coro that is not the main coro
382	calls this function, there will be some one-time resource leak.	396	calls this function, there will be some one-time resource leak.
383		397
384	=cut	398	=cut
385		399
386	sub killall {	400	sub killall {
…		…
390	}	404	}
391	}	405	}
392		406
393	=back	407	=back
394		408
395	=head1 COROUTINE OBJECT METHODS	409	=head1 CORO OBJECT METHODS
396		410
397	These are the methods you can call on coroutine objects (or to create	411	These are the methods you can call on coro objects (or to create
398	them).	412	them).
399		413
400	=over 4	414	=over 4
401		415
402	=item new Coro \&sub [, @args...]	416	=item new Coro \&sub [, @args...]
403		417
404	Create a new coroutine and return it. When the sub returns, the coroutine	418	Create a new coro and return it. When the sub returns, the coro
405	automatically terminates as if C<terminate> with the returned values were	419	automatically terminates as if C<terminate> with the returned values were
406	called. To make the coroutine run you must first put it into the ready	420	called. To make the coro run you must first put it into the ready
407	queue by calling the ready method.	421	queue by calling the ready method.
408		422
409	See C<async> and C<Coro::State::new> for additional info about the	423	See C<async> and C<Coro::State::new> for additional info about the
410	coroutine environment.	424	coro environment.
411		425
412	=cut	426	=cut
413		427
414	sub _coro_run {	428	sub _coro_run {
415	terminate &{+shift};	429	terminate &{+shift};
416	}	430	}
417		431
418	=item $success = $coroutine->ready	432	=item $success = $coro->ready
419		433
420	Put the given coroutine into the end of its ready queue (there is one	434	Put the given coro into the end of its ready queue (there is one
421	queue for each priority) and return true. If the coroutine is already in	435	queue for each priority) and return true. If the coro is already in
422	the ready queue, do nothing and return false.	436	the ready queue, do nothing and return false.
423		437
424	This ensures that the scheduler will resume this coroutine automatically	438	This ensures that the scheduler will resume this coro automatically
425	once all the coroutines of higher priority and all coroutines of the same	439	once all the coro of higher priority and all coro of the same
426	priority that were put into the ready queue earlier have been resumed.	440	priority that were put into the ready queue earlier have been resumed.
427		441
		442	=item $coro->suspend
		443
		444	Suspends the specified coro. A suspended coro works just like any other
		445	coro, except that the scheduler will not select a suspended coro for
		446	execution.
		447
		448	Suspending a coro can be useful when you want to keep the coro from
		449	running, but you don't want to destroy it, or when you want to temporarily
		450	freeze a coro (e.g. for debugging) to resume it later.
		451
		452	A scenario for the former would be to suspend all (other) coros after a
		453	fork and keep them alive, so their destructors aren't called, but new
		454	coros can be created.
		455
		456	=item $coro->resume
		457
		458	If the specified coro was suspended, it will be resumed. Note that when
		459	the coro was in the ready queue when it was suspended, it might have been
		460	unreadied by the scheduler, so an activation might have been lost.
		461
		462	To avoid this, it is best to put a suspended coro into the ready queue
		463	unconditionally, as every synchronisation mechanism must protect itself
		464	against spurious wakeups, and the one in the Coro family certainly do
		465	that.
		466
428	=item $is_ready = $coroutine->is_ready	467	=item $is_ready = $coro->is_ready
429		468
430	Return whether the coroutine is currently the ready queue or not,	469	Returns true iff the Coro object is in the ready queue. Unless the Coro
		470	object gets destroyed, it will eventually be scheduled by the scheduler.
431		471
		472	=item $is_running = $coro->is_running
		473
		474	Returns true iff the Coro object is currently running. Only one Coro object
		475	can ever be in the running state (but it currently is possible to have
		476	multiple running Coro::States).
		477
		478	=item $is_suspended = $coro->is_suspended
		479
		480	Returns true iff this Coro object has been suspended. Suspended Coros will
		481	not ever be scheduled.
		482
432	=item $coroutine->cancel (arg...)	483	=item $coro->cancel (arg...)
433		484
434	Terminates the given coroutine and makes it return the given arguments as	485	Terminates the given Coro and makes it return the given arguments as
435	status (default: the empty list). Never returns if the coroutine is the	486	status (default: the empty list). Never returns if the Coro is the
436	current coroutine.	487	current Coro.
437		488
438	=cut	489	=cut
439		490
440	sub cancel {	491	sub cancel {
441	my $self = shift;	492	my $self = shift;
442		493
443	if ($current == $self) {	494	if ($current == $self) {
444	terminate @_;	495	terminate @_;
445	} else {	496	} else {
446	$self->{_status} = [@_];	497	$self->{_status} = [@_];
447	$self->_cancel;	498	Coro::State::cancel $self;
448	}	499	}
449	}	500	}
450		501
451	=item $coroutine->schedule_to	502	=item $coro->schedule_to
452		503
453	Puts the current coroutine to sleep (like C<Coro::schedule>), but instead	504	Puts the current coro to sleep (like C<Coro::schedule>), but instead
454	of continuing with the next coro from the ready queue, always switch to	505	of continuing with the next coro from the ready queue, always switch to
455	the given coroutine object (regardless of priority etc.). The readyness	506	the given coro object (regardless of priority etc.). The readyness
456	state of that coroutine isn't changed.	507	state of that coro isn't changed.
457		508
458	This is an advanced method for special cases - I'd love to hear about any	509	This is an advanced method for special cases - I'd love to hear about any
459	uses for this one.	510	uses for this one.
460		511
461	=item $coroutine->cede_to	512	=item $coro->cede_to
462		513
463	Like C<schedule_to>, but puts the current coroutine into the ready	514	Like C<schedule_to>, but puts the current coro into the ready
464	queue. This has the effect of temporarily switching to the given	515	queue. This has the effect of temporarily switching to the given
465	coroutine, and continuing some time later.	516	coro, and continuing some time later.
466		517
467	This is an advanced method for special cases - I'd love to hear about any	518	This is an advanced method for special cases - I'd love to hear about any
468	uses for this one.	519	uses for this one.
469		520
470	=item $coroutine->throw ([$scalar])	521	=item $coro->throw ([$scalar])
471		522
472	If C<$throw> is specified and defined, it will be thrown as an exception	523	If C<$throw> is specified and defined, it will be thrown as an exception
473	inside the coroutine at the next convenient point in time. Otherwise	524	inside the coro at the next convenient point in time. Otherwise
474	clears the exception object.	525	clears the exception object.
475		526
476	Coro will check for the exception each time a schedule-like-function	527	Coro will check for the exception each time a schedule-like-function
477	returns, i.e. after each C<schedule>, C<cede>, C<< Coro::Semaphore->down	528	returns, i.e. after each C<schedule>, C<cede>, C<< Coro::Semaphore->down
478	>>, C<< Coro::Handle->readable >> and so on. Most of these functions	529	>>, C<< Coro::Handle->readable >> and so on. Most of these functions
…		…
480		531
481	The exception object will be thrown "as is" with the specified scalar in	532	The exception object will be thrown "as is" with the specified scalar in
482	C<$@>, i.e. if it is a string, no line number or newline will be appended	533	C<$@>, i.e. if it is a string, no line number or newline will be appended
483	(unlike with C<die>).	534	(unlike with C<die>).
484		535
485	This can be used as a softer means than C<cancel> to ask a coroutine to	536	This can be used as a softer means than C<cancel> to ask a coro to
486	end itself, although there is no guarantee that the exception will lead to	537	end itself, although there is no guarantee that the exception will lead to
487	termination, and if the exception isn't caught it might well end the whole	538	termination, and if the exception isn't caught it might well end the whole
488	program.	539	program.
489		540
490	You might also think of C<throw> as being the moral equivalent of	541	You might also think of C<throw> as being the moral equivalent of
491	C<kill>ing a coroutine with a signal (in this case, a scalar).	542	C<kill>ing a coro with a signal (in this case, a scalar).
492		543
493	=item $coroutine->join	544	=item $coro->join
494		545
495	Wait until the coroutine terminates and return any values given to the	546	Wait until the coro terminates and return any values given to the
496	C<terminate> or C<cancel> functions. C<join> can be called concurrently	547	C<terminate> or C<cancel> functions. C<join> can be called concurrently
497	from multiple coroutines, and all will be resumed and given the status	548	from multiple coro, and all will be resumed and given the status
498	return once the C<$coroutine> terminates.	549	return once the C<$coro> terminates.
499		550
500	=cut	551	=cut
501		552
502	sub join {	553	sub join {
503	my $self = shift;	554	my $self = shift;
…		…
514	}	565	}
515		566
516	wantarray ? @{$self->{_status}} : $self->{_status}[0];	567	wantarray ? @{$self->{_status}} : $self->{_status}[0];
517	}	568	}
518		569
519	=item $coroutine->on_destroy (\&cb)	570	=item $coro->on_destroy (\&cb)
520		571
521	Registers a callback that is called when this coroutine gets destroyed,	572	Registers a callback that is called when this coro gets destroyed,
522	but before it is joined. The callback gets passed the terminate arguments,	573	but before it is joined. The callback gets passed the terminate arguments,
523	if any, and I<must not> die, under any circumstances.	574	if any, and I<must not> die, under any circumstances.
524		575
525	=cut	576	=cut
526		577
…		…
528	my ($self, $cb) = @_;	579	my ($self, $cb) = @_;
529		580
530	push @{ $self->{_on_destroy} }, $cb;	581	push @{ $self->{_on_destroy} }, $cb;
531	}	582	}
532		583
533	=item $oldprio = $coroutine->prio ($newprio)	584	=item $oldprio = $coro->prio ($newprio)
534		585
535	Sets (or gets, if the argument is missing) the priority of the	586	Sets (or gets, if the argument is missing) the priority of the
536	coroutine. Higher priority coroutines get run before lower priority	587	coro. Higher priority coro get run before lower priority
537	coroutines. Priorities are small signed integers (currently -4 .. +3),	588	coro. Priorities are small signed integers (currently -4 .. +3),
538	that you can refer to using PRIO_xxx constants (use the import tag :prio	589	that you can refer to using PRIO_xxx constants (use the import tag :prio
539	to get then):	590	to get then):
540		591
541	PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN	592	PRIO_MAX > PRIO_HIGH > PRIO_NORMAL > PRIO_LOW > PRIO_IDLE > PRIO_MIN
542	3 > 1 > 0 > -1 > -3 > -4	593	3 > 1 > 0 > -1 > -3 > -4
543		594
544	# set priority to HIGH	595	# set priority to HIGH
545	current->prio(PRIO_HIGH);	596	current->prio (PRIO_HIGH);
546		597
547	The idle coroutine ($Coro::idle) always has a lower priority than any	598	The idle coro ($Coro::idle) always has a lower priority than any
548	existing coroutine.	599	existing coro.
549		600
550	Changing the priority of the current coroutine will take effect immediately,	601	Changing the priority of the current coro will take effect immediately,
551	but changing the priority of coroutines in the ready queue (but not	602	but changing the priority of coro in the ready queue (but not
552	running) will only take effect after the next schedule (of that	603	running) will only take effect after the next schedule (of that
553	coroutine). This is a bug that will be fixed in some future version.	604	coro). This is a bug that will be fixed in some future version.
554		605
555	=item $newprio = $coroutine->nice ($change)	606	=item $newprio = $coro->nice ($change)
556		607
557	Similar to C<prio>, but subtract the given value from the priority (i.e.	608	Similar to C<prio>, but subtract the given value from the priority (i.e.
558	higher values mean lower priority, just as in unix).	609	higher values mean lower priority, just as in unix).
559		610
560	=item $olddesc = $coroutine->desc ($newdesc)	611	=item $olddesc = $coro->desc ($newdesc)
561		612
562	Sets (or gets in case the argument is missing) the description for this	613	Sets (or gets in case the argument is missing) the description for this
563	coroutine. This is just a free-form string you can associate with a	614	coro. This is just a free-form string you can associate with a
564	coroutine.	615	coro.
565		616
566	This method simply sets the C<< $coroutine->{desc} >> member to the given	617	This method simply sets the C<< $coro->{desc} >> member to the given
567	string. You can modify this member directly if you wish.	618	string. You can modify this member directly if you wish, and in fact, this
		619	is often preferred to indicate major processing states that cna then be
		620	seen for example in a L<Coro::Debug> session:
		621
		622	sub my_long_function {
		623	local $Coro::current->{desc} = "now in my_long_function";
		624	...
		625	$Coro::current->{desc} = "my_long_function: phase 1";
		626	...
		627	$Coro::current->{desc} = "my_long_function: phase 2";
		628	...
		629	}
568		630
569	=cut	631	=cut
570		632
571	sub desc {	633	sub desc {
572	my $old = $_[0]{desc};	634	my $old = $_[0]{desc};
…		…
585		647
586	=over 4	648	=over 4
587		649
588	=item Coro::nready	650	=item Coro::nready
589		651
590	Returns the number of coroutines that are currently in the ready state,	652	Returns the number of coro that are currently in the ready state,
591	i.e. that can be switched to by calling C<schedule> directory or	653	i.e. that can be switched to by calling C<schedule> directory or
592	indirectly. The value C<0> means that the only runnable coroutine is the	654	indirectly. The value C<0> means that the only runnable coro is the
593	currently running one, so C<cede> would have no effect, and C<schedule>	655	currently running one, so C<cede> would have no effect, and C<schedule>
594	would cause a deadlock unless there is an idle handler that wakes up some	656	would cause a deadlock unless there is an idle handler that wakes up some
595	coroutines.	657	coro.
596		658
597	=item my $guard = Coro::guard { ... }	659	=item my $guard = Coro::guard { ... }
598		660
599	This function still exists, but is deprecated. Please use the	661	This function still exists, but is deprecated. Please use the
600	C<Guard::guard> function instead.	662	C<Guard::guard> function instead.
…		…
607		669
608	This utility function takes a BLOCK or code reference and "unblocks" it,	670	This utility function takes a BLOCK or code reference and "unblocks" it,
609	returning a new coderef. Unblocking means that calling the new coderef	671	returning a new coderef. Unblocking means that calling the new coderef
610	will return immediately without blocking, returning nothing, while the	672	will return immediately without blocking, returning nothing, while the
611	original code ref will be called (with parameters) from within another	673	original code ref will be called (with parameters) from within another
612	coroutine.	674	coro.
613		675
614	The reason this function exists is that many event libraries (such as the	676	The reason this function exists is that many event libraries (such as the
615	venerable L<Event\|Event> module) are not coroutine-safe (a weaker form	677	venerable L<Event\|Event> module) are not thread-safe (a weaker form
616	of reentrancy). This means you must not block within event callbacks,	678	of reentrancy). This means you must not block within event callbacks,
617	otherwise you might suffer from crashes or worse. The only event library	679	otherwise you might suffer from crashes or worse. The only event library
618	currently known that is safe to use without C<unblock_sub> is L<EV>.	680	currently known that is safe to use without C<unblock_sub> is L<EV>.
619		681
		682	Coro will try to catch you when you block in the event loop
		683	("FATAL:$Coro::IDLE blocked itself"), but this is just best effort and
		684	only works when you do not run your own event loop.
		685
620	This function allows your callbacks to block by executing them in another	686	This function allows your callbacks to block by executing them in another
621	coroutine where it is safe to block. One example where blocking is handy	687	coro where it is safe to block. One example where blocking is handy
622	is when you use the L<Coro::AIO\|Coro::AIO> functions to save results to	688	is when you use the L<Coro::AIO\|Coro::AIO> functions to save results to
623	disk, for example.	689	disk, for example.
624		690
625	In short: simply use C<unblock_sub { ... }> instead of C<sub { ... }> when	691	In short: simply use C<unblock_sub { ... }> instead of C<sub { ... }> when
626	creating event callbacks that want to block.	692	creating event callbacks that want to block.
627		693
628	If your handler does not plan to block (e.g. simply sends a message to	694	If your handler does not plan to block (e.g. simply sends a message to
629	another coroutine, or puts some other coroutine into the ready queue),	695	another coro, or puts some other coro into the ready queue), there is
630	there is no reason to use C<unblock_sub>.	696	no reason to use C<unblock_sub>.
631		697
632	Note that you also need to use C<unblock_sub> for any other callbacks that	698	Note that you also need to use C<unblock_sub> for any other callbacks that
633	are indirectly executed by any C-based event loop. For example, when you	699	are indirectly executed by any C-based event loop. For example, when you
634	use a module that uses L<AnyEvent> (and you use L<Coro::AnyEvent>) and it	700	use a module that uses L<AnyEvent> (and you use L<Coro::AnyEvent>) and it
635	provides callbacks that are the result of some event callback, then you	701	provides callbacks that are the result of some event callback, then you
…		…
665	unshift @unblock_queue, [$cb, @_];	731	unshift @unblock_queue, [$cb, @_];
666	$unblock_scheduler->ready;	732	$unblock_scheduler->ready;
667	}	733	}
668	}	734	}
669		735
670	=item $cb = Coro::rouse_cb	736	=item $cb = rouse_cb
671		737
672	Create and return a "rouse callback". That's a code reference that,	738	Create and return a "rouse callback". That's a code reference that,
673	when called, will remember a copy of its arguments and notify the owner	739	when called, will remember a copy of its arguments and notify the owner
674	coroutine of the callback.	740	coro of the callback.
675		741
676	See the next function.	742	See the next function.
677		743
678	=item @args = Coro::rouse_wait [$cb]	744	=item @args = rouse_wait [$cb]
679		745
680	Wait for the specified rouse callback (or the last one that was created in	746	Wait for the specified rouse callback (or the last one that was created in
681	this coroutine).	747	this coro).
682		748
683	As soon as the callback is invoked (or when the callback was invoked	749	As soon as the callback is invoked (or when the callback was invoked
684	before C<rouse_wait>), it will return the arguments originally passed to	750	before C<rouse_wait>), it will return the arguments originally passed to
685	the rouse callback.	751	the rouse callback. In scalar context, that means you get the I<last>
		752	argument, just as if C<rouse_wait> had a C<return ($a1, $a2, $a3...)>
		753	statement at the end.
686		754
687	See the section B<HOW TO WAIT FOR A CALLBACK> for an actual usage example.	755	See the section B<HOW TO WAIT FOR A CALLBACK> for an actual usage example.
688		756
689	=back	757	=back
690		758
…		…
692		760
693	1;	761	1;
694		762
695	=head1 HOW TO WAIT FOR A CALLBACK	763	=head1 HOW TO WAIT FOR A CALLBACK
696		764
697	It is very common for a coroutine to wait for some callback to be	765	It is very common for a coro to wait for some callback to be
698	called. This occurs naturally when you use coroutines in an otherwise	766	called. This occurs naturally when you use coro in an otherwise
699	event-based program, or when you use event-based libraries.	767	event-based program, or when you use event-based libraries.
700		768
701	These typically register a callback for some event, and call that callback	769	These typically register a callback for some event, and call that callback
702	when the event occured. In a coroutine, however, you typically want to	770	when the event occured. In a coro, however, you typically want to
703	just wait for the event, simplyifying things.	771	just wait for the event, simplyifying things.
704		772
705	For example C<< AnyEvent->child >> registers a callback to be called when	773	For example C<< AnyEvent->child >> registers a callback to be called when
706	a specific child has exited:	774	a specific child has exited:
707		775
708	my $child_watcher = AnyEvent->child (pid => $pid, cb => sub { ... });	776	my $child_watcher = AnyEvent->child (pid => $pid, cb => sub { ... });
709		777
710	But from withina coroutine, you often just want to write this:	778	But from within a coro, you often just want to write this:
711		779
712	my $status = wait_for_child $pid;	780	my $status = wait_for_child $pid;
713		781
714	Coro offers two functions specifically designed to make this easy,	782	Coro offers two functions specifically designed to make this easy,
715	C<Coro::rouse_cb> and C<Coro::rouse_wait>.	783	C<Coro::rouse_cb> and C<Coro::rouse_wait>.
716		784
717	The first function, C<rouse_cb>, generates and returns a callback that,	785	The first function, C<rouse_cb>, generates and returns a callback that,
718	when invoked, will save its arguments and notify the coroutine that	786	when invoked, will save its arguments and notify the coro that
719	created the callback.	787	created the callback.
720		788
721	The second function, C<rouse_wait>, waits for the callback to be called	789	The second function, C<rouse_wait>, waits for the callback to be called
722	(by calling C<schedule> to go to sleep) and returns the arguments	790	(by calling C<schedule> to go to sleep) and returns the arguments
723	originally passed to the callback.	791	originally passed to the callback.
…		…
738	you can roll your own, using C<schedule>:	806	you can roll your own, using C<schedule>:
739		807
740	sub wait_for_child($) {	808	sub wait_for_child($) {
741	my ($pid) = @_;	809	my ($pid) = @_;
742		810
743	# store the current coroutine in $current,	811	# store the current coro in $current,
744	# and provide result variables for the closure passed to ->child	812	# and provide result variables for the closure passed to ->child
745	my $current = $Coro::current;	813	my $current = $Coro::current;
746	my ($done, $rstatus);	814	my ($done, $rstatus);
747		815
748	# pass a closure to ->child	816	# pass a closure to ->child
…		…
764		832
765	=item fork with pthread backend	833	=item fork with pthread backend
766		834
767	When Coro is compiled using the pthread backend (which isn't recommended	835	When Coro is compiled using the pthread backend (which isn't recommended
768	but required on many BSDs as their libcs are completely broken), then	836	but required on many BSDs as their libcs are completely broken), then
769	coroutines will not survive a fork. There is no known workaround except to	837	coro will not survive a fork. There is no known workaround except to
770	fix your libc and use a saner backend.	838	fix your libc and use a saner backend.
771		839
772	=item perl process emulation ("threads")	840	=item perl process emulation ("threads")
773		841
774	This module is not perl-pseudo-thread-safe. You should only ever use this	842	This module is not perl-pseudo-thread-safe. You should only ever use this
…		…
776	future to allow per-thread schedulers, but Coro::State does not yet allow	844	future to allow per-thread schedulers, but Coro::State does not yet allow
777	this). I recommend disabling thread support and using processes, as having	845	this). I recommend disabling thread support and using processes, as having
778	the windows process emulation enabled under unix roughly halves perl	846	the windows process emulation enabled under unix roughly halves perl
779	performance, even when not used.	847	performance, even when not used.
780		848
781	=item coroutine switching not signal safe	849	=item coro switching is not signal safe
782		850
783	You must not switch to another coroutine from within a signal handler	851	You must not switch to another coro from within a signal handler (only
784	(only relevant with %SIG - most event libraries provide safe signals).	852	relevant with %SIG - most event libraries provide safe signals), I<unless>
		853	you are sure you are not interrupting a Coro function.
785		854
786	That means you I<MUST NOT> call any function that might "block" the	855	That means you I<MUST NOT> call any function that might "block" the
787	current coroutine - C<cede>, C<schedule> C<< Coro::Semaphore->down >> or	856	current coro - C<cede>, C<schedule> C<< Coro::Semaphore->down >> or
788	anything that calls those. Everything else, including calling C<ready>,	857	anything that calls those. Everything else, including calling C<ready>,
789	works.	858	works.
790		859
791	=back	860	=back
792		861
		862
		863	=head1 WINDOWS PROCESS EMULATION
		864
		865	A great many people seem to be confused about ithreads (for example, Chip
		866	Salzenberg called me unintelligent, incapable, stupid and gullible,
		867	while in the same mail making rather confused statements about perl
		868	ithreads (for example, that memory or files would be shared), showing his
		869	lack of understanding of this area - if it is hard to understand for Chip,
		870	it is probably not obvious to everybody).
		871
		872	What follows is an ultra-condensed version of my talk about threads in
		873	scripting languages given on the perl workshop 2009:
		874
		875	The so-called "ithreads" were originally implemented for two reasons:
		876	first, to (badly) emulate unix processes on native win32 perls, and
		877	secondly, to replace the older, real thread model ("5.005-threads").
		878
		879	It does that by using threads instead of OS processes. The difference
		880	between processes and threads is that threads share memory (and other
		881	state, such as files) between threads within a single process, while
		882	processes do not share anything (at least not semantically). That
		883	means that modifications done by one thread are seen by others, while
		884	modifications by one process are not seen by other processes.
		885
		886	The "ithreads" work exactly like that: when creating a new ithreads
		887	process, all state is copied (memory is copied physically, files and code
		888	is copied logically). Afterwards, it isolates all modifications. On UNIX,
		889	the same behaviour can be achieved by using operating system processes,
		890	except that UNIX typically uses hardware built into the system to do this
		891	efficiently, while the windows process emulation emulates this hardware in
		892	software (rather efficiently, but of course it is still much slower than
		893	dedicated hardware).
		894
		895	As mentioned before, loading code, modifying code, modifying data
		896	structures and so on is only visible in the ithreads process doing the
		897	modification, not in other ithread processes within the same OS process.
		898
		899	This is why "ithreads" do not implement threads for perl at all, only
		900	processes. What makes it so bad is that on non-windows platforms, you can
		901	actually take advantage of custom hardware for this purpose (as evidenced
		902	by the forks module, which gives you the (i-) threads API, just much
		903	faster).
		904
		905	Sharing data is in the i-threads model is done by transfering data
		906	structures between threads using copying semantics, which is very slow -
		907	shared data simply does not exist. Benchmarks using i-threads which are
		908	communication-intensive show extremely bad behaviour with i-threads (in
		909	fact, so bad that Coro, which cannot take direct advantage of multiple
		910	CPUs, is often orders of magnitude faster because it shares data using
		911	real threads, refer to my talk for details).
		912
		913	As summary, i-threads use threads to implement processes, while
		914	the compatible forks module uses processes to emulate, uhm,
		915	processes. I-threads slow down every perl program when enabled, and
		916	outside of windows, serve no (or little) practical purpose, but
		917	disadvantages every single-threaded Perl program.
		918
		919	This is the reason that I try to avoid the name "ithreads", as it is
		920	misleading as it implies that it implements some kind of thread model for
		921	perl, and prefer the name "windows process emulation", which describes the
		922	actual use and behaviour of it much better.
793		923
794	=head1 SEE ALSO	924	=head1 SEE ALSO
795		925
796	Event-Loop integration: L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>.	926	Event-Loop integration: L<Coro::AnyEvent>, L<Coro::EV>, L<Coro::Event>.
797		927

Diff Legend

-–
+Removed lines
-+
+Added lines
-<
+Changed lines
->
+Changed lines

Comparing Coro/Coro.pm (file contents): Revision 1.247 by root, Mon Dec 15 02:07:11 2008 UTC vs. Revision 1.281 by root, Tue Dec 7 17:13:43 2010 UTC

Diff Legend

Comparing Coro/Coro.pm (file contents):
Revision 1.247 by root, Mon Dec 15 02:07:11 2008 UTC vs.
Revision 1.281 by root, Tue Dec 7 17:13:43 2010 UTC