[ViewVC] Diff of: cvs/IO-AIO/AIO.pm

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.82 by root, Fri Oct 27 20:10:06 2006 UTC vs.
Revision 1.142 by root, Wed Oct 22 18:15:36 2008 UTC

…		…
5	=head1 SYNOPSIS	5	=head1 SYNOPSIS
6		6
7	use IO::AIO;	7	use IO::AIO;
8		8
9	aio_open "/etc/passwd", O_RDONLY, 0, sub {	9	aio_open "/etc/passwd", O_RDONLY, 0, sub {
10	my ($fh) = @_;	10	my $fh = shift
		11	or die "/etc/passwd: $!";
11	...	12	...
12	};	13	};
13		14
14	aio_unlink "/tmp/file", sub { };	15	aio_unlink "/tmp/file", sub { };
15		16
…		…
25	$req->cancel; # cancel request if still in queue	26	$req->cancel; # cancel request if still in queue
26		27
27	my $grp = aio_group sub { print "all stats done\n" };	28	my $grp = aio_group sub { print "all stats done\n" };
28	add $grp aio_stat "..." for ...;	29	add $grp aio_stat "..." for ...;
29		30
		31	# AnyEvent integration (EV, Event, Glib, Tk, POE, urxvt, pureperl...)
		32	use AnyEvent::AIO;
		33
30	# AnyEvent integration	34	# EV integration
31	open my $fh, "<&=" . IO::AIO::poll_fileno or die "$!";	35	my $w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
32	my $w = AnyEvent->io (fh => $fh, poll => 'r', cb => sub { IO::AIO::poll_cb });
33		36
34	# Event integration	37	# Event integration
35	Event->io (fd => IO::AIO::poll_fileno,	38	Event->io (fd => IO::AIO::poll_fileno,
36	poll => 'r',	39	poll => 'r',
37	cb => \&IO::AIO::poll_cb);	40	cb => \&IO::AIO::poll_cb);
…		…
50		53
51	=head1 DESCRIPTION	54	=head1 DESCRIPTION
52		55
53	This module implements asynchronous I/O using whatever means your	56	This module implements asynchronous I/O using whatever means your
54	operating system supports.	57	operating system supports.
		58
		59	Asynchronous means that operations that can normally block your program
		60	(e.g. reading from disk) will be done asynchronously: the operation
		61	will still block, but you can do something else in the meantime. This
		62	is extremely useful for programs that need to stay interactive even
		63	when doing heavy I/O (GUI programs, high performance network servers
		64	etc.), but can also be used to easily do operations in parallel that are
		65	normally done sequentially, e.g. stat'ing many files, which is much faster
		66	on a RAID volume or over NFS when you do a number of stat operations
		67	concurrently.
		68
		69	While most of this works on all types of file descriptors (for
		70	example sockets), using these functions on file descriptors that
		71	support nonblocking operation (again, sockets, pipes etc.) is very
		72	inefficient. Use an event loop for that (such as the L<Event\|Event>
		73	module): IO::AIO will naturally fit into such an event loop itself.
55		74
56	In this version, a number of threads are started that execute your	75	In this version, a number of threads are started that execute your
57	requests and signal their completion. You don't need thread support	76	requests and signal their completion. You don't need thread support
58	in perl, and the threads created by this module will not be visible	77	in perl, and the threads created by this module will not be visible
59	to perl. In the future, this module might make use of the native aio	78	to perl. In the future, this module might make use of the native aio
60	functions available on many operating systems. However, they are often	79	functions available on many operating systems. However, they are often
61	not well-supported or restricted (Linux doesn't allow them on normal	80	not well-supported or restricted (GNU/Linux doesn't allow them on normal
62	files currently, for example), and they would only support aio_read and	81	files currently, for example), and they would only support aio_read and
63	aio_write, so the remaining functionality would have to be implemented	82	aio_write, so the remaining functionality would have to be implemented
64	using threads anyway.	83	using threads anyway.
65		84
66	Although the module will work with in the presence of other (Perl-)	85	Although the module will work in the presence of other (Perl-) threads,
67	threads, it is currently not reentrant in any way, so use appropriate	86	it is currently not reentrant in any way, so use appropriate locking
68	locking yourself, always call C<poll_cb> from within the same thread, or	87	yourself, always call C<poll_cb> from within the same thread, or never
69	never call C<poll_cb> (or other C<aio_> functions) recursively.	88	call C<poll_cb> (or other C<aio_> functions) recursively.
		89
		90	=head2 EXAMPLE
		91
		92	This is a simple example that uses the Event module and loads
		93	F</etc/passwd> asynchronously:
		94
		95	use Fcntl;
		96	use Event;
		97	use IO::AIO;
		98
		99	# register the IO::AIO callback with Event
		100	Event->io (fd => IO::AIO::poll_fileno,
		101	poll => 'r',
		102	cb => \&IO::AIO::poll_cb);
		103
		104	# queue the request to open /etc/passwd
		105	aio_open "/etc/passwd", O_RDONLY, 0, sub {
		106	my $fh = shift
		107	or die "error while opening: $!";
		108
		109	# stat'ing filehandles is generally non-blocking
		110	my $size = -s $fh;
		111
		112	# queue a request to read the file
		113	my $contents;
		114	aio_read $fh, 0, $size, $contents, 0, sub {
		115	$_[0] == $size
		116	or die "short read: $!";
		117
		118	close $fh;
		119
		120	# file contents now in $contents
		121	print $contents;
		122
		123	# exit event loop and program
		124	Event::unloop;
		125	};
		126	};
		127
		128	# possibly queue up other requests, or open GUI windows,
		129	# check for sockets etc. etc.
		130
		131	# process events as long as there are some:
		132	Event::loop;
70		133
71	=head1 REQUEST ANATOMY AND LIFETIME	134	=head1 REQUEST ANATOMY AND LIFETIME
72		135
73	Every C<aio_*> function creates a request. which is a C data structure not	136	Every C<aio_*> function creates a request. which is a C data structure not
74	directly visible to Perl.	137	directly visible to Perl.
…		…
116	Request has reached the end of its lifetime and holds no resources anymore	179	Request has reached the end of its lifetime and holds no resources anymore
117	(except possibly for the Perl object, but its connection to the actual	180	(except possibly for the Perl object, but its connection to the actual
118	aio request is severed and calling its methods will either do nothing or	181	aio request is severed and calling its methods will either do nothing or
119	result in a runtime error).	182	result in a runtime error).
120		183
		184	=back
		185
121	=cut	186	=cut
122		187
123	package IO::AIO;	188	package IO::AIO;
		189
		190	use Carp ();
124		191
125	no warnings;	192	no warnings;
126	use strict 'vars';	193	use strict 'vars';
127		194
128	use base 'Exporter';	195	use base 'Exporter';
129		196
130	BEGIN {	197	BEGIN {
131	our $VERSION = '2.0';	198	our $VERSION = '3.16';
132		199
133	our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close aio_stat	200	our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close
134	aio_lstat aio_unlink aio_rmdir aio_readdir aio_scandir aio_symlink	201	aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir
135	aio_fsync aio_fdatasync aio_readahead aio_rename aio_link aio_move	202	aio_scandir aio_symlink aio_readlink aio_sync aio_fsync
136	aio_copy aio_group aio_nop aio_mknod);	203	aio_fdatasync aio_sync_file_range aio_pathsync aio_readahead
		204	aio_rename aio_link aio_move aio_copy aio_group
		205	aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown
		206	aio_chmod aio_utime aio_truncate);
		207
137	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));	208	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));
138	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush	209	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush
139	min_parallel max_parallel nreqs nready npending);	210	min_parallel max_parallel max_idle
		211	nreqs nready npending nthreads
		212	max_poll_time max_poll_reqs);
140		213
141	@IO::AIO::GRP::ISA = 'IO::AIO::REQ';	214	@IO::AIO::GRP::ISA = 'IO::AIO::REQ';
142		215
143	require XSLoader;	216	require XSLoader;
144	XSLoader::load ("IO::AIO", $VERSION);	217	XSLoader::load ("IO::AIO", $VERSION);
145	}	218	}
146		219
147	=head1 FUNCTIONS	220	=head1 FUNCTIONS
148		221
149	=head2 AIO FUNCTIONS	222	=head2 AIO REQUEST FUNCTIONS
150		223
151	All the C<aio_*> calls are more or less thin wrappers around the syscall	224	All the C<aio_*> calls are more or less thin wrappers around the syscall
152	with the same name (sans C<aio_>). The arguments are similar or identical,	225	with the same name (sans C<aio_>). The arguments are similar or identical,
153	and they all accept an additional (and optional) C<$callback> argument	226	and they all accept an additional (and optional) C<$callback> argument
154	which must be a code reference. This code reference will get called with	227	which must be a code reference. This code reference will get called with
155	the syscall return code (e.g. most syscalls return C<-1> on error, unlike	228	the syscall return code (e.g. most syscalls return C<-1> on error, unlike
156	perl, which usually delivers "false") as it's sole argument when the given	229	perl, which usually delivers "false") as its sole argument after the given
157	syscall has been executed asynchronously.	230	syscall has been executed asynchronously.
158		231
159	All functions expecting a filehandle keep a copy of the filehandle	232	All functions expecting a filehandle keep a copy of the filehandle
160	internally until the request has finished.	233	internally until the request has finished.
161		234
162	All requests return objects of type L<IO::AIO::REQ> that allow further	235	All functions return request objects of type L<IO::AIO::REQ> that allow
163	manipulation of those requests while they are in-flight.	236	further manipulation of those requests while they are in-flight.
164		237
165	The pathnames you pass to these routines I<must> be absolute and	238	The pathnames you pass to these routines I<must> be absolute and
166	encoded in byte form. The reason for the former is that at the time the	239	encoded as octets. The reason for the former is that at the time the
167	request is being executed, the current working directory could have	240	request is being executed, the current working directory could have
168	changed. Alternatively, you can make sure that you never change the	241	changed. Alternatively, you can make sure that you never change the
169	current working directory.	242	current working directory anywhere in the program and then use relative
		243	paths.
170		244
171	To encode pathnames to byte form, either make sure you either: a)	245	To encode pathnames as octets, either make sure you either: a) always pass
172	always pass in filenames you got from outside (command line, readdir	246	in filenames you got from outside (command line, readdir etc.) without
173	etc.), b) are ASCII or ISO 8859-1, c) use the Encode module and encode	247	tinkering, b) are ASCII or ISO 8859-1, c) use the Encode module and encode
174	your pathnames to the locale (or other) encoding in effect in the user	248	your pathnames to the locale (or other) encoding in effect in the user
175	environment, d) use Glib::filename_from_unicode on unicode filenames or e)	249	environment, d) use Glib::filename_from_unicode on unicode filenames or e)
176	use something else.	250	use something else to ensure your scalar has the correct contents.
		251
		252	This works, btw. independent of the internal UTF-8 bit, which IO::AIO
		253	handles correctly whether it is set or not.
177		254
178	=over 4	255	=over 4
179		256
180	=item $prev_pri = aioreq_pri [$pri]	257	=item $prev_pri = aioreq_pri [$pri]
181		258
…		…
201	aio_read $_[0], ..., sub {	278	aio_read $_[0], ..., sub {
202	...	279	...
203	};	280	};
204	};	281	};
205		282
		283
206	=item aioreq_nice $pri_adjust	284	=item aioreq_nice $pri_adjust
207		285
208	Similar to C<aioreq_pri>, but subtracts the given value from the current	286	Similar to C<aioreq_pri>, but subtracts the given value from the current
209	priority, so effects are cumulative.	287	priority, so the effect is cumulative.
		288
210		289
211	=item aio_open $pathname, $flags, $mode, $callback->($fh)	290	=item aio_open $pathname, $flags, $mode, $callback->($fh)
212		291
213	Asynchronously open or create a file and call the callback with a newly	292	Asynchronously open or create a file and call the callback with a newly
214	created filehandle for the file.	293	created filehandle for the file.
…		…
220	list. They are the same as used by C<sysopen>.	299	list. They are the same as used by C<sysopen>.
221		300
222	Likewise, C<$mode> specifies the mode of the newly created file, if it	301	Likewise, C<$mode> specifies the mode of the newly created file, if it
223	didn't exist and C<O_CREAT> has been given, just like perl's C<sysopen>,	302	didn't exist and C<O_CREAT> has been given, just like perl's C<sysopen>,
224	except that it is mandatory (i.e. use C<0> if you don't create new files,	303	except that it is mandatory (i.e. use C<0> if you don't create new files,
225	and C<0666> or C<0777> if you do).	304	and C<0666> or C<0777> if you do). Note that the C<$mode> will be modified
		305	by the umask in effect then the request is being executed, so better never
		306	change the umask.
226		307
227	Example:	308	Example:
228		309
229	aio_open "/etc/passwd", O_RDONLY, 0, sub {	310	aio_open "/etc/passwd", O_RDONLY, 0, sub {
230	if ($_[0]) {	311	if ($_[0]) {
…		…
233	} else {	314	} else {
234	die "open failed: $!\n";	315	die "open failed: $!\n";
235	}	316	}
236	};	317	};
237		318
		319
238	=item aio_close $fh, $callback->($status)	320	=item aio_close $fh, $callback->($status)
239		321
240	Asynchronously close a file and call the callback with the result	322	Asynchronously close a file and call the callback with the result
241	code. I<WARNING:> although accepted, you should not pass in a perl	323	code.
242	filehandle here, as perl will likely close the file descriptor another
243	time when the filehandle is destroyed. Normally, you can safely call perls
244	C<close> or just let filehandles go out of scope.
245		324
246	This is supposed to be a bug in the API, so that might change. It's	325	Unfortunately, you can't do this to perl. Perl I<insists> very strongly on
247	therefore best to avoid this function.	326	closing the file descriptor associated with the filehandle itself.
		327
		328	Therefore, C<aio_close> will not close the filehandle - instead it will
		329	use dup2 to overwrite the file descriptor with the write-end of a pipe
		330	(the pipe fd will be created on demand and will be cached).
		331
		332	Or in other words: the file descriptor will be closed, but it will not be
		333	free for reuse until the perl filehandle is closed.
		334
		335	=cut
248		336
249	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	337	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
250		338
251	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	339	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
252		340
253	Reads or writes C<length> bytes from the specified C<fh> and C<offset>	341	Reads or writes C<$length> bytes from the specified C<$fh> and C<$offset>
254	into the scalar given by C<data> and offset C<dataoffset> and calls the	342	into the scalar given by C<$data> and offset C<$dataoffset> and calls the
255	callback without the actual number of bytes read (or -1 on error, just	343	callback without the actual number of bytes read (or -1 on error, just
256	like the syscall).	344	like the syscall).
257		345
		346	If C<$offset> is undefined, then the current file descriptor offset will
		347	be used (and updated), otherwise the file descriptor offset will not be
		348	changed by these calls.
		349
		350	If C<$length> is undefined in C<aio_write>, use the remaining length of C<$data>.
		351
		352	If C<$dataoffset> is less than zero, it will be counted from the end of
		353	C<$data>.
		354
258	The C<$data> scalar I<MUST NOT> be modified in any way while the request	355	The C<$data> scalar I<MUST NOT> be modified in any way while the request
259	is outstanding. Modifying it can result in segfaults or WW3 (if the	356	is outstanding. Modifying it can result in segfaults or World War III (if
260	necessary/optional hardware is installed).	357	the necessary/optional hardware is installed).
261		358
262	Example: Read 15 bytes at offset 7 into scalar C<$buffer>, starting at	359	Example: Read 15 bytes at offset 7 into scalar C<$buffer>, starting at
263	offset C<0> within the scalar:	360	offset C<0> within the scalar:
264		361
265	aio_read $fh, 7, 15, $buffer, 0, sub {	362	aio_read $fh, 7, 15, $buffer, 0, sub {
266	$_[0] > 0 or die "read error: $!";	363	$_[0] > 0 or die "read error: $!";
267	print "read $_[0] bytes: <$buffer>\n";	364	print "read $_[0] bytes: <$buffer>\n";
268	};	365	};
		366
269		367
270	=item aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)	368	=item aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
271		369
272	Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts	370	Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts
273	reading at byte offset C<$in_offset>, and starts writing at the current	371	reading at byte offset C<$in_offset>, and starts writing at the current
…		…
287	C<$in_fh> than are written, and there is no way to find out how many	385	C<$in_fh> than are written, and there is no way to find out how many
288	bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only	386	bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only
289	provides the number of bytes written to C<$out_fh>. Only if the result	387	provides the number of bytes written to C<$out_fh>. Only if the result
290	value equals C<$length> one can assume that C<$length> bytes have been	388	value equals C<$length> one can assume that C<$length> bytes have been
291	read.	389	read.
		390
292		391
293	=item aio_readahead $fh,$offset,$length, $callback->($retval)	392	=item aio_readahead $fh,$offset,$length, $callback->($retval)
294		393
295	C<aio_readahead> populates the page cache with data from a file so that	394	C<aio_readahead> populates the page cache with data from a file so that
296	subsequent reads from that file will not block on disk I/O. The C<$offset>	395	subsequent reads from that file will not block on disk I/O. The C<$offset>
…		…
302	file. The current file offset of the file is left unchanged.	401	file. The current file offset of the file is left unchanged.
303		402
304	If that syscall doesn't exist (likely if your OS isn't Linux) it will be	403	If that syscall doesn't exist (likely if your OS isn't Linux) it will be
305	emulated by simply reading the data, which would have a similar effect.	404	emulated by simply reading the data, which would have a similar effect.
306		405
		406
307	=item aio_stat $fh_or_path, $callback->($status)	407	=item aio_stat $fh_or_path, $callback->($status)
308		408
309	=item aio_lstat $fh, $callback->($status)	409	=item aio_lstat $fh, $callback->($status)
310		410
311	Works like perl's C<stat> or C<lstat> in void context. The callback will	411	Works like perl's C<stat> or C<lstat> in void context. The callback will
…		…
324	aio_stat "/etc/passwd", sub {	424	aio_stat "/etc/passwd", sub {
325	$_[0] and die "stat failed: $!";	425	$_[0] and die "stat failed: $!";
326	print "size is ", -s _, "\n";	426	print "size is ", -s _, "\n";
327	};	427	};
328		428
		429
		430	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
		431
		432	Works like perl's C<utime> function (including the special case of $atime
		433	and $mtime being undef). Fractional times are supported if the underlying
		434	syscalls support them.
		435
		436	When called with a pathname, uses utimes(2) if available, otherwise
		437	utime(2). If called on a file descriptor, uses futimes(2) if available,
		438	otherwise returns ENOSYS, so this is not portable.
		439
		440	Examples:
		441
		442	# set atime and mtime to current time (basically touch(1)):
		443	aio_utime "path", undef, undef;
		444	# set atime to current time and mtime to beginning of the epoch:
		445	aio_utime "path", time, undef; # undef==0
		446
		447
		448	=item aio_chown $fh_or_path, $uid, $gid, $callback->($status)
		449
		450	Works like perl's C<chown> function, except that C<undef> for either $uid
		451	or $gid is being interpreted as "do not change" (but -1 can also be used).
		452
		453	Examples:
		454
		455	# same as "chown root path" in the shell:
		456	aio_chown "path", 0, -1;
		457	# same as above:
		458	aio_chown "path", 0, undef;
		459
		460
		461	=item aio_truncate $fh_or_path, $offset, $callback->($status)
		462
		463	Works like truncate(2) or ftruncate(2).
		464
		465
		466	=item aio_chmod $fh_or_path, $mode, $callback->($status)
		467
		468	Works like perl's C<chmod> function.
		469
		470
329	=item aio_unlink $pathname, $callback->($status)	471	=item aio_unlink $pathname, $callback->($status)
330		472
331	Asynchronously unlink (delete) a file and call the callback with the	473	Asynchronously unlink (delete) a file and call the callback with the
332	result code.	474	result code.
333		475
		476
334	=item aio_mknod $path, $mode, $dev, $callback->($status)	477	=item aio_mknod $path, $mode, $dev, $callback->($status)
335		478
		479	[EXPERIMENTAL]
		480
336	Asynchronously create a device node (or fifo). See mknod(2): the only	481	Asynchronously create a device node (or fifo). See mknod(2).
337	portable value for C<$mode> is C<S_IFIFO> ored with permissions, and C<0>	482
338	for C<$dev>.	483	The only (POSIX-) portable way of calling this function is:
		484
		485	aio_mknod $path, IO::AIO::S_IFIFO \| $mode, 0, sub { ...
		486
339		487
340	=item aio_link $srcpath, $dstpath, $callback->($status)	488	=item aio_link $srcpath, $dstpath, $callback->($status)
341		489
342	Asynchronously create a new link to the existing object at C<$srcpath> at	490	Asynchronously create a new link to the existing object at C<$srcpath> at
343	the path C<$dstpath> and call the callback with the result code.	491	the path C<$dstpath> and call the callback with the result code.
344		492
		493
345	=item aio_symlink $srcpath, $dstpath, $callback->($status)	494	=item aio_symlink $srcpath, $dstpath, $callback->($status)
346		495
347	Asynchronously create a new symbolic link to the existing object at C<$srcpath> at	496	Asynchronously create a new symbolic link to the existing object at C<$srcpath> at
348	the path C<$dstpath> and call the callback with the result code.	497	the path C<$dstpath> and call the callback with the result code.
349		498
		499
		500	=item aio_readlink $path, $callback->($link)
		501
		502	Asynchronously read the symlink specified by C<$path> and pass it to
		503	the callback. If an error occurs, nothing or undef gets passed to the
		504	callback.
		505
		506
350	=item aio_rename $srcpath, $dstpath, $callback->($status)	507	=item aio_rename $srcpath, $dstpath, $callback->($status)
351		508
352	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as	509	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as
353	rename(2) and call the callback with the result code.	510	rename(2) and call the callback with the result code.
354		511
		512
		513	=item aio_mkdir $pathname, $mode, $callback->($status)
		514
		515	Asynchronously mkdir (create) a directory and call the callback with
		516	the result code. C<$mode> will be modified by the umask at the time the
		517	request is executed, so do not change your umask.
		518
		519
355	=item aio_rmdir $pathname, $callback->($status)	520	=item aio_rmdir $pathname, $callback->($status)
356		521
357	Asynchronously rmdir (delete) a directory and call the callback with the	522	Asynchronously rmdir (delete) a directory and call the callback with the
358	result code.	523	result code.
		524
359		525
360	=item aio_readdir $pathname, $callback->($entries)	526	=item aio_readdir $pathname, $callback->($entries)
361		527
362	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire	528	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire
363	directory (i.e. opendir + readdir + closedir). The entries will not be	529	directory (i.e. opendir + readdir + closedir). The entries will not be
364	sorted, and will B<NOT> include the C<.> and C<..> entries.	530	sorted, and will B<NOT> include the C<.> and C<..> entries.
365		531
366	The callback a single argument which is either C<undef> or an array-ref	532	The callback a single argument which is either C<undef> or an array-ref
367	with the filenames.	533	with the filenames.
368		534
		535
		536	=item aio_load $path, $data, $callback->($status)
		537
		538	This is a composite request that tries to fully load the given file into
		539	memory. Status is the same as with aio_read.
		540
		541	=cut
		542
		543	sub aio_load($$;$) {
		544	my ($path, undef, $cb) = @_;
		545	my $data = \$_[1];
		546
		547	my $pri = aioreq_pri;
		548	my $grp = aio_group $cb;
		549
		550	aioreq_pri $pri;
		551	add $grp aio_open $path, O_RDONLY, 0, sub {
		552	my $fh = shift
		553	or return $grp->result (-1);
		554
		555	aioreq_pri $pri;
		556	add $grp aio_read $fh, 0, (-s $fh), $$data, 0, sub {
		557	$grp->result ($_[0]);
		558	};
		559	};
		560
		561	$grp
		562	}
		563
369	=item aio_copy $srcpath, $dstpath, $callback->($status)	564	=item aio_copy $srcpath, $dstpath, $callback->($status)
370		565
371	Try to copy the I<file> (directories not supported as either source or	566	Try to copy the I<file> (directories not supported as either source or
372	destination) from C<$srcpath> to C<$dstpath> and call the callback with	567	destination) from C<$srcpath> to C<$dstpath> and call the callback with
373	the C<0> (error) or C<-1> ok.	568	the C<0> (error) or C<-1> ok.
374		569
375	This is a composite request that it creates the destination file with	570	This is a composite request that creates the destination file with
376	mode 0200 and copies the contents of the source file into it using	571	mode 0200 and copies the contents of the source file into it using
377	C<aio_sendfile>, followed by restoring atime, mtime, access mode and	572	C<aio_sendfile>, followed by restoring atime, mtime, access mode and
378	uid/gid, in that order.	573	uid/gid, in that order.
379		574
380	If an error occurs, the partial destination file will be unlinked, if	575	If an error occurs, the partial destination file will be unlinked, if
…		…
405		600
406	# those should not normally block. should. should.	601	# those should not normally block. should. should.
407	utime $stat[8], $stat[9], $dst;	602	utime $stat[8], $stat[9], $dst;
408	chmod $stat[2] & 07777, $dst_fh;	603	chmod $stat[2] & 07777, $dst_fh;
409	chown $stat[4], $stat[5], $dst_fh;	604	chown $stat[4], $stat[5], $dst_fh;
		605
		606	aioreq_pri $pri;
410	close $dst_fh;	607	add $grp aio_close $dst_fh;
411	} else {	608	} else {
412	$grp->result (-1);	609	$grp->result (-1);
413	close $src_fh;	610	close $src_fh;
414	close $dst_fh;	611	close $dst_fh;
415		612
…		…
434		631
435	Try to move the I<file> (directories not supported as either source or	632	Try to move the I<file> (directories not supported as either source or
436	destination) from C<$srcpath> to C<$dstpath> and call the callback with	633	destination) from C<$srcpath> to C<$dstpath> and call the callback with
437	the C<0> (error) or C<-1> ok.	634	the C<0> (error) or C<-1> ok.
438		635
439	This is a composite request that tries to rename(2) the file first. If	636	This is a composite request that tries to rename(2) the file first; if
440	rename files with C<EXDEV>, it copies the file with C<aio_copy> and, if	637	rename fails with C<EXDEV>, it copies the file with C<aio_copy> and, if
441	that is successful, unlinking the C<$srcpath>.	638	that is successful, unlinks the C<$srcpath>.
442		639
443	=cut	640	=cut
444		641
445	sub aio_move($$;$) {	642	sub aio_move($$;$) {
446	my ($src, $dst, $cb) = @_;	643	my ($src, $dst, $cb) = @_;
…		…
520	as those tend to return 0 or 1 as link counts, which disables the	717	as those tend to return 0 or 1 as link counts, which disables the
521	directory counting heuristic.	718	directory counting heuristic.
522		719
523	=cut	720	=cut
524		721
525	sub aio_scandir($$$) {	722	sub aio_scandir($$;$) {
526	my ($path, $maxreq, $cb) = @_;	723	my ($path, $maxreq, $cb) = @_;
527		724
528	my $pri = aioreq_pri;	725	my $pri = aioreq_pri;
529		726
530	my $grp = aio_group $cb;	727	my $grp = aio_group $cb;
…		…
606	};	803	};
607		804
608	$grp	805	$grp
609	}	806	}
610		807
		808	=item aio_rmtree $path, $callback->($status)
		809
		810	Delete a directory tree starting (and including) C<$path>, return the
		811	status of the final C<rmdir> only. This is a composite request that
		812	uses C<aio_scandir> to recurse into and rmdir directories, and unlink
		813	everything else.
		814
		815	=cut
		816
		817	sub aio_rmtree;
		818	sub aio_rmtree($;$) {
		819	my ($path, $cb) = @_;
		820
		821	my $pri = aioreq_pri;
		822	my $grp = aio_group $cb;
		823
		824	aioreq_pri $pri;
		825	add $grp aio_scandir $path, 0, sub {
		826	my ($dirs, $nondirs) = @_;
		827
		828	my $dirgrp = aio_group sub {
		829	add $grp aio_rmdir $path, sub {
		830	$grp->result ($_[0]);
		831	};
		832	};
		833
		834	(aioreq_pri $pri), add $dirgrp aio_rmtree "$path/$_" for @$dirs;
		835	(aioreq_pri $pri), add $dirgrp aio_unlink "$path/$_" for @$nondirs;
		836
		837	add $grp $dirgrp;
		838	};
		839
		840	$grp
		841	}
		842
		843	=item aio_sync $callback->($status)
		844
		845	Asynchronously call sync and call the callback when finished.
		846
611	=item aio_fsync $fh, $callback->($status)	847	=item aio_fsync $fh, $callback->($status)
612		848
613	Asynchronously call fsync on the given filehandle and call the callback	849	Asynchronously call fsync on the given filehandle and call the callback
614	with the fsync result code.	850	with the fsync result code.
615		851
…		…
618	Asynchronously call fdatasync on the given filehandle and call the	854	Asynchronously call fdatasync on the given filehandle and call the
619	callback with the fdatasync result code.	855	callback with the fdatasync result code.
620		856
621	If this call isn't available because your OS lacks it or it couldn't be	857	If this call isn't available because your OS lacks it or it couldn't be
622	detected, it will be emulated by calling C<fsync> instead.	858	detected, it will be emulated by calling C<fsync> instead.
		859
		860	=item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
		861
		862	Sync the data portion of the file specified by C<$offset> and C<$length>
		863	to disk (but NOT the metadata), by calling the Linux-specific
		864	sync_file_range call. If sync_file_range is not available or it returns
		865	ENOSYS, then fdatasync or fsync is being substituted.
		866
		867	C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>,
		868	C<IO::AIO::SYNC_FILE_RANGE_WRITE> and
		869	C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range
		870	manpage for details.
		871
		872	=item aio_pathsync $path, $callback->($status)
		873
		874	This request tries to open, fsync and close the given path. This is a
		875	composite request intended to sync directories after directory operations
		876	(E.g. rename). This might not work on all operating systems or have any
		877	specific effect, but usually it makes sure that directory changes get
		878	written to disc. It works for anything that can be opened for read-only,
		879	not just directories.
		880
		881	Passes C<0> when everything went ok, and C<-1> on error.
		882
		883	=cut
		884
		885	sub aio_pathsync($;$) {
		886	my ($path, $cb) = @_;
		887
		888	my $pri = aioreq_pri;
		889	my $grp = aio_group $cb;
		890
		891	aioreq_pri $pri;
		892	add $grp aio_open $path, O_RDONLY, 0, sub {
		893	my ($fh) = @_;
		894	if ($fh) {
		895	aioreq_pri $pri;
		896	add $grp aio_fsync $fh, sub {
		897	$grp->result ($_[0]);
		898
		899	aioreq_pri $pri;
		900	add $grp aio_close $fh;
		901	};
		902	} else {
		903	$grp->result (-1);
		904	}
		905	};
		906
		907	$grp
		908	}
623		909
624	=item aio_group $callback->(...)	910	=item aio_group $callback->(...)
625		911
626	This is a very special aio request: Instead of doing something, it is a	912	This is a very special aio request: Instead of doing something, it is a
627	container for other aio requests, which is useful if you want to bundle	913	container for other aio requests, which is useful if you want to bundle
…		…
739	Their lifetime, simplified, looks like this: when they are empty, they	1025	Their lifetime, simplified, looks like this: when they are empty, they
740	will finish very quickly. If they contain only requests that are in the	1026	will finish very quickly. If they contain only requests that are in the
741	C<done> state, they will also finish. Otherwise they will continue to	1027	C<done> state, they will also finish. Otherwise they will continue to
742	exist.	1028	exist.
743		1029
744	That means after creating a group you have some time to add requests. And	1030	That means after creating a group you have some time to add requests
745	in the callbacks of those requests, you can add further requests to the	1031	(precisely before the callback has been invoked, which is only done within
746	group. And only when all those requests have finished will the the group	1032	the C<poll_cb>). And in the callbacks of those requests, you can add
747	itself finish.	1033	further requests to the group. And only when all those requests have
		1034	finished will the the group itself finish.
748		1035
749	=over 4	1036	=over 4
750		1037
751	=item add $grp ...	1038	=item add $grp ...
752		1039
…		…
764	itself. Useful when you queued a lot of events but got a result early.	1051	itself. Useful when you queued a lot of events but got a result early.
765		1052
766	=item $grp->result (...)	1053	=item $grp->result (...)
767		1054
768	Set the result value(s) that will be passed to the group callback when all	1055	Set the result value(s) that will be passed to the group callback when all
769	subrequests have finished and set thre groups errno to the current value	1056	subrequests have finished and set the groups errno to the current value
770	of errno (just like calling C<errno> without an error number). By default,	1057	of errno (just like calling C<errno> without an error number). By default,
771	no argument will be passed and errno is zero.	1058	no argument will be passed and errno is zero.
772		1059
773	=item $grp->errno ([$errno])	1060	=item $grp->errno ([$errno])
774		1061
…		…
785	=item feed $grp $callback->($grp)	1072	=item feed $grp $callback->($grp)
786		1073
787	Sets a feeder/generator on this group: every group can have an attached	1074	Sets a feeder/generator on this group: every group can have an attached
788	generator that generates requests if idle. The idea behind this is that,	1075	generator that generates requests if idle. The idea behind this is that,
789	although you could just queue as many requests as you want in a group,	1076	although you could just queue as many requests as you want in a group,
790	this might starve other requests for a potentially long time. For	1077	this might starve other requests for a potentially long time. For example,
791	example, C<aio_scandir> might generate hundreds of thousands C<aio_stat>	1078	C<aio_scandir> might generate hundreds of thousands C<aio_stat> requests,
792	requests, delaying any later requests for a long time.	1079	delaying any later requests for a long time.
793		1080
794	To avoid this, and allow incremental generation of requests, you can	1081	To avoid this, and allow incremental generation of requests, you can
795	instead a group and set a feeder on it that generates those requests. The	1082	instead a group and set a feeder on it that generates those requests. The
796	feed callback will be called whenever there are few enough (see C<limit>,	1083	feed callback will be called whenever there are few enough (see C<limit>,
797	below) requests active in the group itself and is expected to queue more	1084	below) requests active in the group itself and is expected to queue more
…		…
801	not impose any limits).	1088	not impose any limits).
802		1089
803	If the feed does not queue more requests when called, it will be	1090	If the feed does not queue more requests when called, it will be
804	automatically removed from the group.	1091	automatically removed from the group.
805		1092
806	If the feed limit is C<0>, it will be set to C<2> automatically.	1093	If the feed limit is C<0> when this method is called, it will be set to
		1094	C<2> automatically.
807		1095
808	Example:	1096	Example:
809		1097
810	# stat all files in @files, but only ever use four aio requests concurrently:	1098	# stat all files in @files, but only ever use four aio requests concurrently:
811		1099
…		…
823	Sets the feeder limit for the group: The feeder will be called whenever	1111	Sets the feeder limit for the group: The feeder will be called whenever
824	the group contains less than this many requests.	1112	the group contains less than this many requests.
825		1113
826	Setting the limit to C<0> will pause the feeding process.	1114	Setting the limit to C<0> will pause the feeding process.
827		1115
		1116	The default value for the limit is C<0>, but note that setting a feeder
		1117	automatically bumps it up to C<2>.
		1118
828	=back	1119	=back
829		1120
830	=head2 SUPPORT FUNCTIONS	1121	=head2 SUPPORT FUNCTIONS
		1122
		1123	=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION
831		1124
832	=over 4	1125	=over 4
833		1126
834	=item $fileno = IO::AIO::poll_fileno	1127	=item $fileno = IO::AIO::poll_fileno
835		1128
…		…
840		1133
841	See C<poll_cb> for an example.	1134	See C<poll_cb> for an example.
842		1135
843	=item IO::AIO::poll_cb	1136	=item IO::AIO::poll_cb
844		1137
845	Process all outstanding events on the result pipe. You have to call this	1138	Process some outstanding events on the result pipe. You have to call this
846	regularly. Returns the number of events processed. Returns immediately	1139	regularly. Returns C<0> if all events could be processed, or C<-1> if it
847	when no events are outstanding.	1140	returned earlier for whatever reason. Returns immediately when no events
		1141	are outstanding. The amount of events processed depends on the settings of
		1142	C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>.
848		1143
849	If not all requests were processed for whatever reason, the filehandle	1144	If not all requests were processed for whatever reason, the filehandle
850	will still be ready when C<poll_cb> returns.	1145	will still be ready when C<poll_cb> returns, so normally you don't have to
		1146	do anything special to have it called later.
851		1147
852	Example: Install an Event watcher that automatically calls	1148	Example: Install an Event watcher that automatically calls
853	IO::AIO::poll_cb with high priority:	1149	IO::AIO::poll_cb with high priority:
854		1150
855	Event->io (fd => IO::AIO::poll_fileno,	1151	Event->io (fd => IO::AIO::poll_fileno,
856	poll => 'r', async => 1,	1152	poll => 'r', async => 1,
857	cb => \&IO::AIO::poll_cb);	1153	cb => \&IO::AIO::poll_cb);
858		1154
859	=item IO::AIO::poll_some $max_requests	1155	=item IO::AIO::max_poll_reqs $nreqs
860		1156
861	Similar to C<poll_cb>, but only processes up to C<$max_requests> requests	1157	=item IO::AIO::max_poll_time $seconds
862	at a time.
863		1158
864	Useful if you want to ensure some level of interactiveness when perl is	1159	These set the maximum number of requests (default C<0>, meaning infinity)
865	not fast enough to process all requests in time.	1160	that are being processed by C<IO::AIO::poll_cb> in one call, respectively
		1161	the maximum amount of time (default C<0>, meaning infinity) spent in
		1162	C<IO::AIO::poll_cb> to process requests (more correctly the mininum amount
		1163	of time C<poll_cb> is allowed to use).
		1164
		1165	Setting C<max_poll_time> to a non-zero value creates an overhead of one
		1166	syscall per request processed, which is not normally a problem unless your
		1167	callbacks are really really fast or your OS is really really slow (I am
		1168	not mentioning Solaris here). Using C<max_poll_reqs> incurs no overhead.
		1169
		1170	Setting these is useful if you want to ensure some level of
		1171	interactiveness when perl is not fast enough to process all requests in
		1172	time.
		1173
		1174	For interactive programs, values such as C<0.01> to C<0.1> should be fine.
866		1175
867	Example: Install an Event watcher that automatically calls	1176	Example: Install an Event watcher that automatically calls
868	IO::AIO::poll_some with low priority, to ensure that other parts of the	1177	IO::AIO::poll_cb with low priority, to ensure that other parts of the
869	program get the CPU sometimes even under high AIO load.	1178	program get the CPU sometimes even under high AIO load.
870		1179
		1180	# try not to spend much more than 0.1s in poll_cb
		1181	IO::AIO::max_poll_time 0.1;
		1182
		1183	# use a low priority so other tasks have priority
871	Event->io (fd => IO::AIO::poll_fileno,	1184	Event->io (fd => IO::AIO::poll_fileno,
872	poll => 'r', nice => 1,	1185	poll => 'r', nice => 1,
873	cb => sub { IO::AIO::poll_some 256 });	1186	cb => &IO::AIO::poll_cb);
874		1187
875	=item IO::AIO::poll_wait	1188	=item IO::AIO::poll_wait
876		1189
		1190	If there are any outstanding requests and none of them in the result
877	Wait till the result filehandle becomes ready for reading (simply does a	1191	phase, wait till the result filehandle becomes ready for reading (simply
878	C<select> on the filehandle. This is useful if you want to synchronously wait	1192	does a C<select> on the filehandle. This is useful if you want to
879	for some requests to finish).	1193	synchronously wait for some requests to finish).
880		1194
881	See C<nreqs> for an example.	1195	See C<nreqs> for an example.
882		1196
		1197	=item IO::AIO::poll
		1198
		1199	Waits until some requests have been handled.
		1200
		1201	Returns the number of requests processed, but is otherwise strictly
		1202	equivalent to:
		1203
		1204	IO::AIO::poll_wait, IO::AIO::poll_cb
		1205
883	=item IO::AIO::nreqs	1206	=item IO::AIO::flush
884		1207
885	Returns the number of requests currently in the ready, execute or pending	1208	Wait till all outstanding AIO requests have been handled.
886	states (i.e. for which their callback has not been invoked yet).
887		1209
888	Example: wait till there are no outstanding requests anymore:	1210	Strictly equivalent to:
889		1211
890	IO::AIO::poll_wait, IO::AIO::poll_cb	1212	IO::AIO::poll_wait, IO::AIO::poll_cb
891	while IO::AIO::nreqs;	1213	while IO::AIO::nreqs;
892		1214
893	=item IO::AIO::nready	1215	=back
894		1216
895	Returns the number of requests currently in the ready state (not yet	1217	=head3 CONTROLLING THE NUMBER OF THREADS
896	executed).
897		1218
898	=item IO::AIO::npending	1219	=over
899
900	Returns the number of requests currently in the pending state (executed,
901	but not yet processed by poll_cb).
902
903	=item IO::AIO::flush
904
905	Wait till all outstanding AIO requests have been handled.
906
907	Strictly equivalent to:
908
909	IO::AIO::poll_wait, IO::AIO::poll_cb
910	while IO::AIO::nreqs;
911
912	=item IO::AIO::poll
913
914	Waits until some requests have been handled.
915
916	Strictly equivalent to:
917
918	IO::AIO::poll_wait, IO::AIO::poll_cb
919	if IO::AIO::nreqs;
920		1220
921	=item IO::AIO::min_parallel $nthreads	1221	=item IO::AIO::min_parallel $nthreads
922		1222
923	Set the minimum number of AIO threads to C<$nthreads>. The current	1223	Set the minimum number of AIO threads to C<$nthreads>. The current
924	default is C<8>, which means eight asynchronous operations can execute	1224	default is C<8>, which means eight asynchronous operations can execute
925	concurrently at any one time (the number of outstanding requests,	1225	concurrently at any one time (the number of outstanding requests,
926	however, is unlimited).	1226	however, is unlimited).
927		1227
928	IO::AIO starts threads only on demand, when an AIO request is queued and	1228	IO::AIO starts threads only on demand, when an AIO request is queued and
929	no free thread exists.	1229	no free thread exists. Please note that queueing up a hundred requests can
		1230	create demand for a hundred threads, even if it turns out that everything
		1231	is in the cache and could have been processed faster by a single thread.
930		1232
931	It is recommended to keep the number of threads relatively low, as some	1233	It is recommended to keep the number of threads relatively low, as some
932	Linux kernel versions will scale negatively with the number of threads	1234	Linux kernel versions will scale negatively with the number of threads
933	(higher parallelity => MUCH higher latency). With current Linux 2.6	1235	(higher parallelity => MUCH higher latency). With current Linux 2.6
934	versions, 4-32 threads should be fine.	1236	versions, 4-32 threads should be fine.
…		…
948	This module automatically runs C<max_parallel 0> at program end, to ensure	1250	This module automatically runs C<max_parallel 0> at program end, to ensure
949	that all threads are killed and that there are no outstanding requests.	1251	that all threads are killed and that there are no outstanding requests.
950		1252
951	Under normal circumstances you don't need to call this function.	1253	Under normal circumstances you don't need to call this function.
952		1254
		1255	=item IO::AIO::max_idle $nthreads
		1256
		1257	Limit the number of threads (default: 4) that are allowed to idle (i.e.,
		1258	threads that did not get a request to process within 10 seconds). That
		1259	means if a thread becomes idle while C<$nthreads> other threads are also
		1260	idle, it will free its resources and exit.
		1261
		1262	This is useful when you allow a large number of threads (e.g. 100 or 1000)
		1263	to allow for extremely high load situations, but want to free resources
		1264	under normal circumstances (1000 threads can easily consume 30MB of RAM).
		1265
		1266	The default is probably ok in most situations, especially if thread
		1267	creation is fast. If thread creation is very slow on your system you might
		1268	want to use larger values.
		1269
953	=item $oldmaxreqs = IO::AIO::max_outstanding $maxreqs	1270	=item IO::AIO::max_outstanding $maxreqs
954		1271
955	This is a very bad function to use in interactive programs because it	1272	This is a very bad function to use in interactive programs because it
956	blocks, and a bad way to reduce concurrency because it is inexact: Better	1273	blocks, and a bad way to reduce concurrency because it is inexact: Better
957	use an C<aio_group> together with a feed callback.	1274	use an C<aio_group> together with a feed callback.
958		1275
959	Sets the maximum number of outstanding requests to C<$nreqs>. If you	1276	Sets the maximum number of outstanding requests to C<$nreqs>. If you
960	to queue up more than this number of requests, the next call to the	1277	do queue up more than this number of requests, the next call to the
961	C<poll_cb> (and C<poll_some> and other functions calling C<poll_cb>)	1278	C<poll_cb> (and C<poll_some> and other functions calling C<poll_cb>)
962	function will block until the limit is no longer exceeded.	1279	function will block until the limit is no longer exceeded.
963		1280
964	The default value is very large, so there is no practical limit on the	1281	The default value is very large, so there is no practical limit on the
965	number of outstanding requests.	1282	number of outstanding requests.
966		1283
967	You can still queue as many requests as you want. Therefore,	1284	You can still queue as many requests as you want. Therefore,
968	C<max_oustsanding> is mainly useful in simple scripts (with low values) or	1285	C<max_outstanding> is mainly useful in simple scripts (with low values) or
969	as a stop gap to shield against fatal memory overflow (with large values).	1286	as a stop gap to shield against fatal memory overflow (with large values).
970		1287
971	=back	1288	=back
972		1289
		1290	=head3 STATISTICAL INFORMATION
		1291
		1292	=over
		1293
		1294	=item IO::AIO::nreqs
		1295
		1296	Returns the number of requests currently in the ready, execute or pending
		1297	states (i.e. for which their callback has not been invoked yet).
		1298
		1299	Example: wait till there are no outstanding requests anymore:
		1300
		1301	IO::AIO::poll_wait, IO::AIO::poll_cb
		1302	while IO::AIO::nreqs;
		1303
		1304	=item IO::AIO::nready
		1305
		1306	Returns the number of requests currently in the ready state (not yet
		1307	executed).
		1308
		1309	=item IO::AIO::npending
		1310
		1311	Returns the number of requests currently in the pending state (executed,
		1312	but not yet processed by poll_cb).
		1313
		1314	=back
		1315
973	=cut	1316	=cut
974		1317
975	# support function to convert a fd into a perl filehandle
976	sub _fd2fh {
977	return undef if $_[0] < 0;
978
979	# try to generate nice filehandles
980	my $sym = "IO::AIO::fd#$_[0]";
981	local *$sym;
982
983	open *$sym, "+<&=$_[0]" # usually works under any unix
984	or open *$sym, "<&=$_[0]" # cygwin needs this
985	or open *$sym, ">&=$_[0]" # or this
986	or return undef;
987
988	*$sym
989	}
990
991	min_parallel 8;	1318	min_parallel 8;
992		1319
993	END {	1320	END { flush }
994	flush;
995	};
996		1321
997	1;	1322	1;
998		1323
999	=head2 FORK BEHAVIOUR	1324	=head2 FORK BEHAVIOUR
1000		1325
…		…
1020	bytes of memory. In addition, stat requests need a stat buffer (possibly	1345	bytes of memory. In addition, stat requests need a stat buffer (possibly
1021	a few hundred bytes), readdir requires a result buffer and so on. Perl	1346	a few hundred bytes), readdir requires a result buffer and so on. Perl
1022	scalars and other data passed into aio requests will also be locked and	1347	scalars and other data passed into aio requests will also be locked and
1023	will consume memory till the request has entered the done state.	1348	will consume memory till the request has entered the done state.
1024		1349
1025	This is now awfully much, so queuing lots of requests is not usually a	1350	This is not awfully much, so queuing lots of requests is not usually a
1026	problem.	1351	problem.
1027		1352
1028	Per-thread usage:	1353	Per-thread usage:
1029		1354
1030	In the execution phase, some aio requests require more memory for	1355	In the execution phase, some aio requests require more memory for
…		…
1035		1360
1036	Known bugs will be fixed in the next release.	1361	Known bugs will be fixed in the next release.
1037		1362
1038	=head1 SEE ALSO	1363	=head1 SEE ALSO
1039		1364
1040	L<Coro::AIO>.	1365	L<AnyEvent::AIO> for easy integration into event loops, L<Coro::AIO> for a
		1366	more natural syntax.
1041		1367
1042	=head1 AUTHOR	1368	=head1 AUTHOR
1043		1369
1044	Marc Lehmann <schmorp@schmorp.de>	1370	Marc Lehmann <schmorp@schmorp.de>
1045	http://home.schmorp.de/	1371	http://home.schmorp.de/

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Comparing IO-AIO/AIO.pm (file contents): Revision 1.82 by root, Fri Oct 27 20:10:06 2006 UTC vs. Revision 1.142 by root, Wed Oct 22 18:15:36 2008 UTC

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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.82 by root, Fri Oct 27 20:10:06 2006 UTC vs.
Revision 1.142 by root, Wed Oct 22 18:15:36 2008 UTC