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Revision 1.107 by root, Fri Jun 1 05:52:59 2007 UTC vs.
Revision 1.184 by root, Mon Nov 1 22:03:43 2010 UTC

…		…
4		4
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", IO::AIO::O_RDONLY, 0, sub {
10	my $fh = shift	10	my $fh = shift
11	or die "/etc/passwd: $!";	11	or die "/etc/passwd: $!";
12	...	12	...
13	};	13	};
14		14
…		…
26	$req->cancel; # cancel request if still in queue	26	$req->cancel; # cancel request if still in queue
27		27
28	my $grp = aio_group sub { print "all stats done\n" };	28	my $grp = aio_group sub { print "all stats done\n" };
29	add $grp aio_stat "..." for ...;	29	add $grp aio_stat "..." for ...;
30		30
31	# AnyEvent integration
32	open my $fh, "<&=" . IO::AIO::poll_fileno or die "$!";
33	my $w = AnyEvent->io (fh => $fh, poll => 'r', cb => sub { IO::AIO::poll_cb });
34
35	# Event integration
36	Event->io (fd => IO::AIO::poll_fileno,
37	poll => 'r',
38	cb => \&IO::AIO::poll_cb);
39
40	# Glib/Gtk2 integration
41	add_watch Glib::IO IO::AIO::poll_fileno,
42	in => sub { IO::AIO::poll_cb; 1 };
43
44	# Tk integration
45	Tk::Event::IO->fileevent (IO::AIO::poll_fileno, "",
46	readable => \&IO::AIO::poll_cb);
47
48	# Danga::Socket integration
49	Danga::Socket->AddOtherFds (IO::AIO::poll_fileno =>
50	\&IO::AIO::poll_cb);
51
52	=head1 DESCRIPTION	31	=head1 DESCRIPTION
53		32
54	This module implements asynchronous I/O using whatever means your	33	This module implements asynchronous I/O using whatever means your
55	operating system supports.	34	operating system supports. It is implemented as an interface to C<libeio>
		35	(L<http://software.schmorp.de/pkg/libeio.html>).
56		36
57	Asynchronous means that operations that can normally block your program	37	Asynchronous means that operations that can normally block your program
58	(e.g. reading from disk) will be done asynchronously: the operation	38	(e.g. reading from disk) will be done asynchronously: the operation
59	will still block, but you can do something else in the meantime. This	39	will still block, but you can do something else in the meantime. This
60	is extremely useful for programs that need to stay interactive even	40	is extremely useful for programs that need to stay interactive even
…		…
62	etc.), but can also be used to easily do operations in parallel that are	42	etc.), but can also be used to easily do operations in parallel that are
63	normally done sequentially, e.g. stat'ing many files, which is much faster	43	normally done sequentially, e.g. stat'ing many files, which is much faster
64	on a RAID volume or over NFS when you do a number of stat operations	44	on a RAID volume or over NFS when you do a number of stat operations
65	concurrently.	45	concurrently.
66		46
67	While most of this works on all types of file descriptors (for example	47	While most of this works on all types of file descriptors (for
68	sockets), using these functions on file descriptors that support	48	example sockets), using these functions on file descriptors that
69	nonblocking operation (again, sockets, pipes etc.) is very inefficient or	49	support nonblocking operation (again, sockets, pipes etc.) is
70	might not work (aio_read fails on sockets/pipes/fifos). Use an event loop	50	very inefficient. Use an event loop for that (such as the L<EV>
71	for that (such as the L<Event|Event> module): IO::AIO will naturally fit	51	module): IO::AIO will naturally fit into such an event loop itself.
72	into such an event loop itself.
73		52
74	In this version, a number of threads are started that execute your	53	In this version, a number of threads are started that execute your
75	requests and signal their completion. You don't need thread support	54	requests and signal their completion. You don't need thread support
76	in perl, and the threads created by this module will not be visible	55	in perl, and the threads created by this module will not be visible
77	to perl. In the future, this module might make use of the native aio	56	to perl. In the future, this module might make use of the native aio
…		…
79	not well-supported or restricted (GNU/Linux doesn't allow them on normal	58	not well-supported or restricted (GNU/Linux doesn't allow them on normal
80	files currently, for example), and they would only support aio_read and	59	files currently, for example), and they would only support aio_read and
81	aio_write, so the remaining functionality would have to be implemented	60	aio_write, so the remaining functionality would have to be implemented
82	using threads anyway.	61	using threads anyway.
83		62
84	Although the module will work with in the presence of other (Perl-)	63	Although the module will work in the presence of other (Perl-) threads,
85	threads, it is currently not reentrant in any way, so use appropriate	64	it is currently not reentrant in any way, so use appropriate locking
86	locking yourself, always call C<poll_cb> from within the same thread, or	65	yourself, always call C<poll_cb> from within the same thread, or never
87	never call C<poll_cb> (or other C<aio_> functions) recursively.	66	call C<poll_cb> (or other C<aio_> functions) recursively.
88		67
89	=head2 EXAMPLE	68	=head2 EXAMPLE
90		69
91	This is a simple example that uses the Event module and loads	70	This is a simple example that uses the EV module and loads
92	F</etc/passwd> asynchronously:	71	F</etc/passwd> asynchronously:
93		72
94	use Fcntl;	73	use Fcntl;
95	use Event;	74	use EV;
96	use IO::AIO;	75	use IO::AIO;
97		76
98	# register the IO::AIO callback with Event	77	# register the IO::AIO callback with EV
99	Event->io (fd => IO::AIO::poll_fileno,	78	my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
100	poll => 'r',
101	cb => \&IO::AIO::poll_cb);
102		79
103	# queue the request to open /etc/passwd	80	# queue the request to open /etc/passwd
104	aio_open "/etc/passwd", O_RDONLY, 0, sub {	81	aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub {
105	my $fh = shift	82	my $fh = shift
106	or die "error while opening: $!";	83	or die "error while opening: $!";
107		84
108	# stat'ing filehandles is generally non-blocking	85	# stat'ing filehandles is generally non-blocking
109	my $size = -s $fh;	86	my $size = -s $fh;
…		…
118		95
119	# file contents now in $contents	96	# file contents now in $contents
120	print $contents;	97	print $contents;
121		98
122	# exit event loop and program	99	# exit event loop and program
123	Event::unloop;	100	EV::unloop;
124	};	101	};
125	};	102	};
126		103
127	# possibly queue up other requests, or open GUI windows,	104	# possibly queue up other requests, or open GUI windows,
128	# check for sockets etc. etc.	105	# check for sockets etc. etc.
129		106
130	# process events as long as there are some:	107	# process events as long as there are some:
131	Event::loop;	108	EV::loop;
132		109
133	=head1 REQUEST ANATOMY AND LIFETIME	110	=head1 REQUEST ANATOMY AND LIFETIME
134		111
135	Every C<aio_*> function creates a request. which is a C data structure not	112	Every C<aio_*> function creates a request. which is a C data structure not
136	directly visible to Perl.	113	directly visible to Perl.
…		…
184		161
185	=cut	162	=cut
186		163
187	package IO::AIO;	164	package IO::AIO;
188		165
189	no warnings;	166	use Carp ();
190	use strict 'vars';	167
		168	use common::sense;
191		169
192	use base 'Exporter';	170	use base 'Exporter';
193		171
194	BEGIN {	172	BEGIN {
195	our $VERSION = '2.4';	173	our $VERSION = '3.7';
196		174
197	our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close aio_stat	175	our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close
198	aio_lstat aio_unlink aio_rmdir aio_readdir aio_scandir aio_symlink	176	aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx
199	aio_readlink aio_fsync aio_fdatasync aio_readahead aio_rename aio_link	177	aio_scandir aio_symlink aio_readlink aio_sync aio_fsync
		178	aio_fdatasync aio_sync_file_range aio_pathsync aio_readahead
		179	aio_rename aio_link aio_move aio_copy aio_group
200	aio_move aio_copy aio_group aio_nop aio_mknod aio_load aio_rmtree aio_mkdir	180	aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown
201	aio_chown aio_chmod aio_utime);	181	aio_chmod aio_utime aio_truncate
		182	aio_msync aio_mtouch aio_mlock aio_mlockall
		183	aio_statvfs);
		184
202	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice aio_block));	185	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));
203	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush	186	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush
204	min_parallel max_parallel max_idle	187	min_parallel max_parallel max_idle
205	nreqs nready npending nthreads	188	nreqs nready npending nthreads
206	max_poll_time max_poll_reqs);	189	max_poll_time max_poll_reqs
		190	sendfile fadvise madvise
		191	mmap munmap munlock munlockall);
		192
		193	push @AIO_REQ, qw(aio_busy); # not exported
207		194
208	@IO::AIO::GRP::ISA = 'IO::AIO::REQ';	195	@IO::AIO::GRP::ISA = 'IO::AIO::REQ';
209		196
210	require XSLoader;	197	require XSLoader;
211	XSLoader::load ("IO::AIO", $VERSION);	198	XSLoader::load ("IO::AIO", $VERSION);
212	}	199	}
213		200
214	=head1 FUNCTIONS	201	=head1 FUNCTIONS
		202
		203	=head2 QUICK OVERVIEW
		204
		205	This section simply lists the prototypes of the most important functions
		206	for quick reference. See the following sections for function-by-function
		207	documentation.
		208
		209	aio_open $pathname, $flags, $mode, $callback->($fh)
		210	aio_close $fh, $callback->($status)
		211	aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
		212	aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
		213	aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
		214	aio_readahead $fh,$offset,$length, $callback->($retval)
		215	aio_stat $fh_or_path, $callback->($status)
		216	aio_lstat $fh, $callback->($status)
		217	aio_statvfs $fh_or_path, $callback->($statvfs)
		218	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
		219	aio_chown $fh_or_path, $uid, $gid, $callback->($status)
		220	aio_truncate $fh_or_path, $offset, $callback->($status)
		221	aio_chmod $fh_or_path, $mode, $callback->($status)
		222	aio_unlink $pathname, $callback->($status)
		223	aio_mknod $path, $mode, $dev, $callback->($status)
		224	aio_link $srcpath, $dstpath, $callback->($status)
		225	aio_symlink $srcpath, $dstpath, $callback->($status)
		226	aio_readlink $path, $callback->($link)
		227	aio_rename $srcpath, $dstpath, $callback->($status)
		228	aio_mkdir $pathname, $mode, $callback->($status)
		229	aio_rmdir $pathname, $callback->($status)
		230	aio_readdir $pathname, $callback->($entries)
		231	aio_readdirx $pathname, $flags, $callback->($entries, $flags)
		232	IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST
		233	IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN
		234	aio_load $path, $data, $callback->($status)
		235	aio_copy $srcpath, $dstpath, $callback->($status)
		236	aio_move $srcpath, $dstpath, $callback->($status)
		237	aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
		238	aio_rmtree $path, $callback->($status)
		239	aio_sync $callback->($status)
		240	aio_fsync $fh, $callback->($status)
		241	aio_fdatasync $fh, $callback->($status)
		242	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
		243	aio_pathsync $path, $callback->($status)
		244	aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
		245	aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
		246	aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
		247	aio_mlockall $flags, $callback->($status)
		248	aio_group $callback->(...)
		249	aio_nop $callback->()
		250
		251	$prev_pri = aioreq_pri [$pri]
		252	aioreq_nice $pri_adjust
		253
		254	IO::AIO::poll_wait
		255	IO::AIO::poll_cb
		256	IO::AIO::poll
		257	IO::AIO::flush
		258	IO::AIO::max_poll_reqs $nreqs
		259	IO::AIO::max_poll_time $seconds
		260	IO::AIO::min_parallel $nthreads
		261	IO::AIO::max_parallel $nthreads
		262	IO::AIO::max_idle $nthreads
		263	IO::AIO::max_outstanding $maxreqs
		264	IO::AIO::nreqs
		265	IO::AIO::nready
		266	IO::AIO::npending
		267
		268	IO::AIO::sendfile $ofh, $ifh, $offset, $count
		269	IO::AIO::fadvise $fh, $offset, $len, $advice
		270	IO::AIO::madvise $scalar, $offset, $length, $advice
		271	IO::AIO::mprotect $scalar, $offset, $length, $protect
		272	IO::AIO::munlock $scalar, $offset = 0, $length = undef
		273	IO::AIO::munlockall
215		274
216	=head2 AIO REQUEST FUNCTIONS	275	=head2 AIO REQUEST FUNCTIONS
217		276
218	All the C<aio_*> calls are more or less thin wrappers around the syscall	277	All the C<aio_*> calls are more or less thin wrappers around the syscall
219	with the same name (sans C<aio_>). The arguments are similar or identical,	278	with the same name (sans C<aio_>). The arguments are similar or identical,
220	and they all accept an additional (and optional) C<$callback> argument	279	and they all accept an additional (and optional) C<$callback> argument
221	which must be a code reference. This code reference will get called with	280	which must be a code reference. This code reference will get called with
222	the syscall return code (e.g. most syscalls return C<-1> on error, unlike	281	the syscall return code (e.g. most syscalls return C<-1> on error, unlike
223	perl, which usually delivers "false") as it's sole argument when the given	282	perl, which usually delivers "false") as its sole argument after the given
224	syscall has been executed asynchronously.	283	syscall has been executed asynchronously.
225		284
226	All functions expecting a filehandle keep a copy of the filehandle	285	All functions expecting a filehandle keep a copy of the filehandle
227	internally until the request has finished.	286	internally until the request has finished.
228		287
…		…
242	your pathnames to the locale (or other) encoding in effect in the user	301	your pathnames to the locale (or other) encoding in effect in the user
243	environment, d) use Glib::filename_from_unicode on unicode filenames or e)	302	environment, d) use Glib::filename_from_unicode on unicode filenames or e)
244	use something else to ensure your scalar has the correct contents.	303	use something else to ensure your scalar has the correct contents.
245		304
246	This works, btw. independent of the internal UTF-8 bit, which IO::AIO	305	This works, btw. independent of the internal UTF-8 bit, which IO::AIO
247	handles correctly wether it is set or not.	306	handles correctly whether it is set or not.
248		307
249	=over 4	308	=over 4
250		309
251	=item $prev_pri = aioreq_pri [$pri]	310	=item $prev_pri = aioreq_pri [$pri]
252		311
…		…
299	by the umask in effect then the request is being executed, so better never	358	by the umask in effect then the request is being executed, so better never
300	change the umask.	359	change the umask.
301		360
302	Example:	361	Example:
303		362
304	aio_open "/etc/passwd", O_RDONLY, 0, sub {	363	aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub {
305	if ($_[0]) {	364	if ($_[0]) {
306	print "open successful, fh is $_[0]\n";	365	print "open successful, fh is $_[0]\n";
307	...	366	...
308	} else {	367	} else {
309	die "open failed: $!\n";	368	die "open failed: $!\n";
…		…
312		371
313		372
314	=item aio_close $fh, $callback->($status)	373	=item aio_close $fh, $callback->($status)
315		374
316	Asynchronously close a file and call the callback with the result	375	Asynchronously close a file and call the callback with the result
317	code. I<WARNING:> although accepted, you should not pass in a perl	376	code.
318	filehandle here, as perl will likely close the file descriptor another
319	time when the filehandle is destroyed. Normally, you can safely call perls
320	C<close> or just let filehandles go out of scope.
321		377
322	This is supposed to be a bug in the API, so that might change. It's	378	Unfortunately, you can't do this to perl. Perl I<insists> very strongly on
323	therefore best to avoid this function.	379	closing the file descriptor associated with the filehandle itself.
324		380
		381	Therefore, C<aio_close> will not close the filehandle - instead it will
		382	use dup2 to overwrite the file descriptor with the write-end of a pipe
		383	(the pipe fd will be created on demand and will be cached).
		384
		385	Or in other words: the file descriptor will be closed, but it will not be
		386	free for reuse until the perl filehandle is closed.
		387
		388	=cut
325		389
326	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	390	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
327		391
328	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	392	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
329		393
330	Reads or writes C<length> bytes from the specified C<fh> and C<offset>	394	Reads or writes C<$length> bytes from or to the specified C<$fh> and
331	into the scalar given by C<data> and offset C<dataoffset> and calls the	395	C<$offset> into the scalar given by C<$data> and offset C<$dataoffset>
332	callback without the actual number of bytes read (or -1 on error, just	396	and calls the callback without the actual number of bytes read (or -1 on
333	like the syscall).	397	error, just like the syscall).
		398
		399	C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to
		400	offset plus the actual number of bytes read.
		401
		402	If C<$offset> is undefined, then the current file descriptor offset will
		403	be used (and updated), otherwise the file descriptor offset will not be
		404	changed by these calls.
		405
		406	If C<$length> is undefined in C<aio_write>, use the remaining length of
		407	C<$data>.
		408
		409	If C<$dataoffset> is less than zero, it will be counted from the end of
		410	C<$data>.
334		411
335	The C<$data> scalar I<MUST NOT> be modified in any way while the request	412	The C<$data> scalar I<MUST NOT> be modified in any way while the request
336	is outstanding. Modifying it can result in segfaults or WW3 (if the	413	is outstanding. Modifying it can result in segfaults or World War III (if
337	necessary/optional hardware is installed).	414	the necessary/optional hardware is installed).
338		415
339	Example: Read 15 bytes at offset 7 into scalar C<$buffer>, starting at	416	Example: Read 15 bytes at offset 7 into scalar C<$buffer>, starting at
340	offset C<0> within the scalar:	417	offset C<0> within the scalar:
341		418
342	aio_read $fh, 7, 15, $buffer, 0, sub {	419	aio_read $fh, 7, 15, $buffer, 0, sub {
…		…
353	than one C<aio_sendfile> per C<$out_fh>, as they will interfere with each	430	than one C<aio_sendfile> per C<$out_fh>, as they will interfere with each
354	other.	431	other.
355		432
356	This call tries to make use of a native C<sendfile> syscall to provide	433	This call tries to make use of a native C<sendfile> syscall to provide
357	zero-copy operation. For this to work, C<$out_fh> should refer to a	434	zero-copy operation. For this to work, C<$out_fh> should refer to a
358	socket, and C<$in_fh> should refer to mmap'able file.	435	socket, and C<$in_fh> should refer to an mmap'able file.
359		436
360	If the native sendfile call fails or is not implemented, it will be	437	If a native sendfile cannot be found or it fails with C<ENOSYS>,
		438	C<ENOTSUP>, C<EOPNOTSUPP>, C<EAFNOSUPPORT>, C<EPROTOTYPE> or C<ENOTSOCK>,
361	emulated, so you can call C<aio_sendfile> on any type of filehandle	439	it will be emulated, so you can call C<aio_sendfile> on any type of
362	regardless of the limitations of the operating system.	440	filehandle regardless of the limitations of the operating system.
363		441
364	Please note, however, that C<aio_sendfile> can read more bytes from	442	Please note, however, that C<aio_sendfile> can read more bytes from
365	C<$in_fh> than are written, and there is no way to find out how many	443	C<$in_fh> than are written, and there is no way to find out how many
366	bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only	444	bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only
367	provides the number of bytes written to C<$out_fh>. Only if the result	445	provides the number of bytes written to C<$out_fh>. Only if the result
…		…
405	$_[0] and die "stat failed: $!";	483	$_[0] and die "stat failed: $!";
406	print "size is ", -s _, "\n";	484	print "size is ", -s _, "\n";
407	};	485	};
408		486
409		487
		488	=item aio_statvfs $fh_or_path, $callback->($statvfs)
		489
		490	Works like the POSIX C<statvfs> or C<fstatvfs> syscalls, depending on
		491	whether a file handle or path was passed.
		492
		493	On success, the callback is passed a hash reference with the following
		494	members: C<bsize>, C<frsize>, C<blocks>, C<bfree>, C<bavail>, C<files>,
		495	C<ffree>, C<favail>, C<fsid>, C<flag> and C<namemax>. On failure, C<undef>
		496	is passed.
		497
		498	The following POSIX IO::AIO::ST_* constants are defined: C<ST_RDONLY> and
		499	C<ST_NOSUID>.
		500
		501	The following non-POSIX IO::AIO::ST_* flag masks are defined to
		502	their correct value when available, or to C<0> on systems that do
		503	not support them: C<ST_NODEV>, C<ST_NOEXEC>, C<ST_SYNCHRONOUS>,
		504	C<ST_MANDLOCK>, C<ST_WRITE>, C<ST_APPEND>, C<ST_IMMUTABLE>, C<ST_NOATIME>,
		505	C<ST_NODIRATIME> and C<ST_RELATIME>.
		506
		507	Example: stat C</wd> and dump out the data if successful.
		508
		509	aio_statvfs "/wd", sub {
		510	my $f = $_[0]
		511	or die "statvfs: $!";
		512
		513	use Data::Dumper;
		514	say Dumper $f;
		515	};
		516
		517	# result:
		518	{
		519	bsize => 1024,
		520	bfree => 4333064312,
		521	blocks => 10253828096,
		522	files => 2050765568,
		523	flag => 4096,
		524	favail => 2042092649,
		525	bavail => 4333064312,
		526	ffree => 2042092649,
		527	namemax => 255,
		528	frsize => 1024,
		529	fsid => 1810
		530	}
		531
		532
410	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	533	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
411		534
412	Works like perl's C<utime> function (including the special case of $atime	535	Works like perl's C<utime> function (including the special case of $atime
413	and $mtime being undef). Fractional times are supported if the underlying	536	and $mtime being undef). Fractional times are supported if the underlying
414	syscalls support them.	537	syscalls support them.
…		…
436	aio_chown "path", 0, -1;	559	aio_chown "path", 0, -1;
437	# same as above:	560	# same as above:
438	aio_chown "path", 0, undef;	561	aio_chown "path", 0, undef;
439		562
440		563
		564	=item aio_truncate $fh_or_path, $offset, $callback->($status)
		565
		566	Works like truncate(2) or ftruncate(2).
		567
		568
441	=item aio_chmod $fh_or_path, $mode, $callback->($status)	569	=item aio_chmod $fh_or_path, $mode, $callback->($status)
442		570
443	Works like perl's C<chmod> function.	571	Works like perl's C<chmod> function.
444		572
445		573
…		…
502		630
503	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire	631	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire
504	directory (i.e. opendir + readdir + closedir). The entries will not be	632	directory (i.e. opendir + readdir + closedir). The entries will not be
505	sorted, and will B<NOT> include the C<.> and C<..> entries.	633	sorted, and will B<NOT> include the C<.> and C<..> entries.
506		634
507	The callback a single argument which is either C<undef> or an array-ref	635	The callback is passed a single argument which is either C<undef> or an
508	with the filenames.	636	array-ref with the filenames.
		637
		638
		639	=item aio_readdirx $pathname, $flags, $callback->($entries, $flags)
		640
		641	Quite similar to C<aio_readdir>, but the C<$flags> argument allows to tune
		642	behaviour and output format. In case of an error, C<$entries> will be
		643	C<undef>.
		644
		645	The flags are a combination of the following constants, ORed together (the
		646	flags will also be passed to the callback, possibly modified):
		647
		648	=over 4
		649
		650	=item IO::AIO::READDIR_DENTS
		651
		652	When this flag is off, then the callback gets an arrayref with of names
		653	only (as with C<aio_readdir>), otherwise it gets an arrayref with
		654	C<[$name, $type, $inode]> arrayrefs, each describing a single directory
		655	entry in more detail.
		656
		657	C<$name> is the name of the entry.
		658
		659	C<$type> is one of the C<IO::AIO::DT_xxx> constants:
		660
		661	C<IO::AIO::DT_UNKNOWN>, C<IO::AIO::DT_FIFO>, C<IO::AIO::DT_CHR>, C<IO::AIO::DT_DIR>,
		662	C<IO::AIO::DT_BLK>, C<IO::AIO::DT_REG>, C<IO::AIO::DT_LNK>, C<IO::AIO::DT_SOCK>,
		663	C<IO::AIO::DT_WHT>.
		664
		665	C<IO::AIO::DT_UNKNOWN> means just that: readdir does not know. If you need to
		666	know, you have to run stat yourself. Also, for speed reasons, the C<$type>
		667	scalars are read-only: you can not modify them.
		668
		669	C<$inode> is the inode number (which might not be exact on systems with 64
		670	bit inode numbers and 32 bit perls). This field has unspecified content on
		671	systems that do not deliver the inode information.
		672
		673	=item IO::AIO::READDIR_DIRS_FIRST
		674
		675	When this flag is set, then the names will be returned in an order where
		676	likely directories come first. This is useful when you need to quickly
		677	find directories, or you want to find all directories while avoiding to
		678	stat() each entry.
		679
		680	If the system returns type information in readdir, then this is used
		681	to find directories directly. Otherwise, likely directories are files
		682	beginning with ".", or otherwise files with no dots, of which files with
		683	short names are tried first.
		684
		685	=item IO::AIO::READDIR_STAT_ORDER
		686
		687	When this flag is set, then the names will be returned in an order
		688	suitable for stat()'ing each one. That is, when you plan to stat()
		689	all files in the given directory, then the returned order will likely
		690	be fastest.
		691
		692	If both this flag and C<IO::AIO::READDIR_DIRS_FIRST> are specified, then
		693	the likely dirs come first, resulting in a less optimal stat order.
		694
		695	=item IO::AIO::READDIR_FOUND_UNKNOWN
		696
		697	This flag should not be set when calling C<aio_readdirx>. Instead, it
		698	is being set by C<aio_readdirx>, when any of the C<$type>'s found were
		699	C<IO::AIO::DT_UNKNOWN>. The absense of this flag therefore indicates that all
		700	C<$type>'s are known, which can be used to speed up some algorithms.
		701
		702	=back
509		703
510		704
511	=item aio_load $path, $data, $callback->($status)	705	=item aio_load $path, $data, $callback->($status)
512		706
513	This is a composite request that tries to fully load the given file into	707	This is a composite request that tries to fully load the given file into
514	memory. Status is the same as with aio_read.	708	memory. Status is the same as with aio_read.
515		709
516	=cut	710	=cut
517		711
518	sub aio_load($$;$) {	712	sub aio_load($$;$) {
519	aio_block {
520	my ($path, undef, $cb) = @_;	713	my ($path, undef, $cb) = @_;
521	my $data = \$_[1];	714	my $data = \$_[1];
522		715
523	my $pri = aioreq_pri;	716	my $pri = aioreq_pri;
524	my $grp = aio_group $cb;	717	my $grp = aio_group $cb;
		718
		719	aioreq_pri $pri;
		720	add $grp aio_open $path, O_RDONLY, 0, sub {
		721	my $fh = shift
		722	or return $grp->result (-1);
525		723
526	aioreq_pri $pri;	724	aioreq_pri $pri;
527	add $grp aio_open $path, O_RDONLY, 0, sub {
528	my $fh = shift
529	or return $grp->result (-1);
530
531	aioreq_pri $pri;
532	add $grp aio_read $fh, 0, (-s $fh), $$data, 0, sub {	725	add $grp aio_read $fh, 0, (-s $fh), $$data, 0, sub {
533	$grp->result ($_[0]);	726	$grp->result ($_[0]);
534	};
535	};	727	};
536
537	$grp
538	}	728	};
		729
		730	$grp
539	}	731	}
540		732
541	=item aio_copy $srcpath, $dstpath, $callback->($status)	733	=item aio_copy $srcpath, $dstpath, $callback->($status)
542		734
543	Try to copy the I<file> (directories not supported as either source or	735	Try to copy the I<file> (directories not supported as either source or
544	destination) from C<$srcpath> to C<$dstpath> and call the callback with	736	destination) from C<$srcpath> to C<$dstpath> and call the callback with
545	the C<0> (error) or C<-1> ok.	737	a status of C<0> (ok) or C<-1> (error, see C<$!>).
546		738
547	This is a composite request that it creates the destination file with	739	This is a composite request that creates the destination file with
548	mode 0200 and copies the contents of the source file into it using	740	mode 0200 and copies the contents of the source file into it using
549	C<aio_sendfile>, followed by restoring atime, mtime, access mode and	741	C<aio_sendfile>, followed by restoring atime, mtime, access mode and
550	uid/gid, in that order.	742	uid/gid, in that order.
551		743
552	If an error occurs, the partial destination file will be unlinked, if	744	If an error occurs, the partial destination file will be unlinked, if
…		…
554	errors are being ignored.	746	errors are being ignored.
555		747
556	=cut	748	=cut
557		749
558	sub aio_copy($$;$) {	750	sub aio_copy($$;$) {
559	aio_block {
560	my ($src, $dst, $cb) = @_;	751	my ($src, $dst, $cb) = @_;
561		752
562	my $pri = aioreq_pri;	753	my $pri = aioreq_pri;
563	my $grp = aio_group $cb;	754	my $grp = aio_group $cb;
564		755
565	aioreq_pri $pri;	756	aioreq_pri $pri;
566	add $grp aio_open $src, O_RDONLY, 0, sub {	757	add $grp aio_open $src, O_RDONLY, 0, sub {
567	if (my $src_fh = $_[0]) {	758	if (my $src_fh = $_[0]) {
568	my @stat = stat $src_fh;	759	my @stat = stat $src_fh; # hmm, might block over nfs?
569		760
570	aioreq_pri $pri;	761	aioreq_pri $pri;
571	add $grp aio_open $dst, O_CREAT | O_WRONLY | O_TRUNC, 0200, sub {	762	add $grp aio_open $dst, O_CREAT | O_WRONLY | O_TRUNC, 0200, sub {
572	if (my $dst_fh = $_[0]) {	763	if (my $dst_fh = $_[0]) {
573	aioreq_pri $pri;	764	aioreq_pri $pri;
574	add $grp aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub {	765	add $grp aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub {
575	if ($_[0] == $stat[7]) {	766	if ($_[0] == $stat[7]) {
576	$grp->result (0);	767	$grp->result (0);
577	close $src_fh;	768	close $src_fh;
578		769
579	# those should not normally block. should. should.
580	utime $stat[8], $stat[9], $dst;
581	chmod $stat[2] & 07777, $dst_fh;
582	chown $stat[4], $stat[5], $dst_fh;
583	close $dst_fh;
584	} else {	770	my $ch = sub {
585	$grp->result (-1);
586	close $src_fh;
587	close $dst_fh;
588
589	aioreq $pri;	771	aioreq_pri $pri;
		772	add $grp aio_chmod $dst_fh, $stat[2] & 07777, sub {
		773	aioreq_pri $pri;
		774	add $grp aio_chown $dst_fh, $stat[4], $stat[5], sub {
		775	aioreq_pri $pri;
590	add $grp aio_unlink $dst;	776	add $grp aio_close $dst_fh;
		777	}
		778	};
591	}	779	};
		780
		781	aioreq_pri $pri;
		782	add $grp aio_utime $dst_fh, $stat[8], $stat[9], sub {
		783	if ($_[0] < 0 && $! == ENOSYS) {
		784	aioreq_pri $pri;
		785	add $grp aio_utime $dst, $stat[8], $stat[9], $ch;
		786	} else {
		787	$ch->();
		788	}
		789	};
		790	} else {
		791	$grp->result (-1);
		792	close $src_fh;
		793	close $dst_fh;
		794
		795	aioreq $pri;
		796	add $grp aio_unlink $dst;
592	};	797	}
593	} else {
594	$grp->result (-1);
595	}	798	};
		799	} else {
		800	$grp->result (-1);
596	},	801	}
597
598	} else {
599	$grp->result (-1);
600	}	802	},
		803
		804	} else {
		805	$grp->result (-1);
601	};	806	}
602
603	$grp
604	}	807	};
		808
		809	$grp
605	}	810	}
606		811
607	=item aio_move $srcpath, $dstpath, $callback->($status)	812	=item aio_move $srcpath, $dstpath, $callback->($status)
608		813
609	Try to move the I<file> (directories not supported as either source or	814	Try to move the I<file> (directories not supported as either source or
610	destination) from C<$srcpath> to C<$dstpath> and call the callback with	815	destination) from C<$srcpath> to C<$dstpath> and call the callback with
611	the C<0> (error) or C<-1> ok.	816	a status of C<0> (ok) or C<-1> (error, see C<$!>).
612		817
613	This is a composite request that tries to rename(2) the file first. If	818	This is a composite request that tries to rename(2) the file first; if
614	rename files with C<EXDEV>, it copies the file with C<aio_copy> and, if	819	rename fails with C<EXDEV>, it copies the file with C<aio_copy> and, if
615	that is successful, unlinking the C<$srcpath>.	820	that is successful, unlinks the C<$srcpath>.
616		821
617	=cut	822	=cut
618		823
619	sub aio_move($$;$) {	824	sub aio_move($$;$) {
620	aio_block {
621	my ($src, $dst, $cb) = @_;	825	my ($src, $dst, $cb) = @_;
622		826
623	my $pri = aioreq_pri;	827	my $pri = aioreq_pri;
624	my $grp = aio_group $cb;	828	my $grp = aio_group $cb;
625		829
626	aioreq_pri $pri;	830	aioreq_pri $pri;
627	add $grp aio_rename $src, $dst, sub {	831	add $grp aio_rename $src, $dst, sub {
628	if ($_[0] && $! == EXDEV) {	832	if ($_[0] && $! == EXDEV) {
629	aioreq_pri $pri;	833	aioreq_pri $pri;
630	add $grp aio_copy $src, $dst, sub {	834	add $grp aio_copy $src, $dst, sub {
631	$grp->result ($_[0]);
632
633	if (!$_[0]) {
634	aioreq_pri $pri;
635	add $grp aio_unlink $src;
636	}
637	};
638	} else {
639	$grp->result ($_[0]);	835	$grp->result ($_[0]);
		836
		837	if (!$_[0]) {
		838	aioreq_pri $pri;
		839	add $grp aio_unlink $src;
		840	}
640	}	841	};
		842	} else {
		843	$grp->result ($_[0]);
641	};	844	}
642
643	$grp
644	}	845	};
		846
		847	$grp
645	}	848	}
646		849
647	=item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)	850	=item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
648		851
649	Scans a directory (similar to C<aio_readdir>) but additionally tries to	852	Scans a directory (similar to C<aio_readdir>) but additionally tries to
…		…
669		872
670	Implementation notes.	873	Implementation notes.
671		874
672	The C<aio_readdir> cannot be avoided, but C<stat()>'ing every entry can.	875	The C<aio_readdir> cannot be avoided, but C<stat()>'ing every entry can.
673		876
		877	If readdir returns file type information, then this is used directly to
		878	find directories.
		879
674	After reading the directory, the modification time, size etc. of the	880	Otherwise, after reading the directory, the modification time, size etc.
675	directory before and after the readdir is checked, and if they match (and	881	of the directory before and after the readdir is checked, and if they
676	isn't the current time), the link count will be used to decide how many	882	match (and isn't the current time), the link count will be used to decide
677	entries are directories (if >= 2). Otherwise, no knowledge of the number	883	how many entries are directories (if >= 2). Otherwise, no knowledge of the
678	of subdirectories will be assumed.	884	number of subdirectories will be assumed.
679		885
680	Then entries will be sorted into likely directories (everything without	886	Then entries will be sorted into likely directories a non-initial dot
681	a non-initial dot currently) and likely non-directories (everything	887	currently) and likely non-directories (see C<aio_readdirx>). Then every
682	else). Then every entry plus an appended C</.> will be C<stat>'ed,	888	entry plus an appended C</.> will be C<stat>'ed, likely directories first,
683	likely directories first. If that succeeds, it assumes that the entry	889	in order of their inode numbers. If that succeeds, it assumes that the
684	is a directory or a symlink to directory (which will be checked	890	entry is a directory or a symlink to directory (which will be checked
685	seperately). This is often faster than stat'ing the entry itself because	891	seperately). This is often faster than stat'ing the entry itself because
686	filesystems might detect the type of the entry without reading the inode	892	filesystems might detect the type of the entry without reading the inode
687	data (e.g. ext2fs filetype feature).	893	data (e.g. ext2fs filetype feature), even on systems that cannot return
		894	the filetype information on readdir.
688		895
689	If the known number of directories (link count - 2) has been reached, the	896	If the known number of directories (link count - 2) has been reached, the
690	rest of the entries is assumed to be non-directories.	897	rest of the entries is assumed to be non-directories.
691		898
692	This only works with certainty on POSIX (= UNIX) filesystems, which	899	This only works with certainty on POSIX (= UNIX) filesystems, which
…		…
697	directory counting heuristic.	904	directory counting heuristic.
698		905
699	=cut	906	=cut
700		907
701	sub aio_scandir($$;$) {	908	sub aio_scandir($$;$) {
702	aio_block {
703	my ($path, $maxreq, $cb) = @_;	909	my ($path, $maxreq, $cb) = @_;
704		910
705	my $pri = aioreq_pri;	911	my $pri = aioreq_pri;
706		912
707	my $grp = aio_group $cb;	913	my $grp = aio_group $cb;
708		914
709	$maxreq = 4 if $maxreq <= 0;	915	$maxreq = 4 if $maxreq <= 0;
710		916
711	# stat once	917	# stat once
		918	aioreq_pri $pri;
		919	add $grp aio_stat $path, sub {
		920	return $grp->result () if $_[0];
		921	my $now = time;
		922	my $hash1 = join ":", (stat _)[0,1,3,7,9];
		923
		924	# read the directory entries
712	aioreq_pri $pri;	925	aioreq_pri $pri;
713	add $grp aio_stat $path, sub {	926	add $grp aio_readdirx $path, READDIR_DIRS_FIRST, sub {
		927	my $entries = shift
714	return $grp->result () if $_[0];	928	or return $grp->result ();
715	my $now = time;
716	my $hash1 = join ":", (stat _)[0,1,3,7,9];
717		929
718	# read the directory entries	930	# stat the dir another time
719	aioreq_pri $pri;	931	aioreq_pri $pri;
720	add $grp aio_readdir $path, sub {
721	my $entries = shift
722	or return $grp->result ();
723
724	# stat the dir another time
725	aioreq_pri $pri;
726	add $grp aio_stat $path, sub {	932	add $grp aio_stat $path, sub {
727	my $hash2 = join ":", (stat _)[0,1,3,7,9];	933	my $hash2 = join ":", (stat _)[0,1,3,7,9];
728		934
729	my $ndirs;	935	my $ndirs;
730		936
731	# take the slow route if anything looks fishy	937	# take the slow route if anything looks fishy
732	if ($hash1 ne $hash2 or (stat _)[9] == $now) {	938	if ($hash1 ne $hash2 or (stat _)[9] == $now) {
733	$ndirs = -1;	939	$ndirs = -1;
734	} else {	940	} else {
735	# if nlink == 2, we are finished	941	# if nlink == 2, we are finished
736	# on non-posix-fs's, we rely on nlink < 2	942	# for non-posix-fs's, we rely on nlink < 2
737	$ndirs = (stat _)[3] - 2	943	$ndirs = (stat _)[3] - 2
738	or return $grp->result ([], $entries);	944	or return $grp->result ([], $entries);
739	}	945	}
740		946
741	# sort into likely dirs and likely nondirs
742	# dirs == files without ".", short entries first
743	$entries = [map $_->[0],
744	sort { $b->[1] cmp $a->[1] }
745	map [$_, sprintf "%s%04d", (/.\./ ? "1" : "0"), length],
746	@$entries];
747
748	my (@dirs, @nondirs);	947	my (@dirs, @nondirs);
749		948
750	my $statgrp = add $grp aio_group sub {	949	my $statgrp = add $grp aio_group sub {
751	$grp->result (\@dirs, \@nondirs);	950	$grp->result (\@dirs, \@nondirs);
752	};	951	};
753		952
754	limit $statgrp $maxreq;	953	limit $statgrp $maxreq;
755	feed $statgrp sub {	954	feed $statgrp sub {
756	return unless @$entries;	955	return unless @$entries;
757	my $entry = pop @$entries;	956	my $entry = shift @$entries;
758		957
759	aioreq_pri $pri;	958	aioreq_pri $pri;
760	add $statgrp aio_stat "$path/$entry/.", sub {	959	add $statgrp aio_stat "$path/$entry/.", sub {
761	if ($_[0] < 0) {	960	if ($_[0] < 0) {
762	push @nondirs, $entry;	961	push @nondirs, $entry;
763	} else {	962	} else {
764	# need to check for real directory	963	# need to check for real directory
765	aioreq_pri $pri;	964	aioreq_pri $pri;
766	add $statgrp aio_lstat "$path/$entry", sub {	965	add $statgrp aio_lstat "$path/$entry", sub {
767	if (-d _) {	966	if (-d _) {
768	push @dirs, $entry;	967	push @dirs, $entry;
769		968
770	unless (--$ndirs) {	969	unless (--$ndirs) {
771	push @nondirs, @$entries;	970	push @nondirs, @$entries;
772	feed $statgrp;	971	feed $statgrp;
773	}
774	} else {
775	push @nondirs, $entry;
776	}	972	}
		973	} else {
		974	push @nondirs, $entry;
777	}	975	}
778	}	976	}
779	};	977	}
780	};	978	};
781	};	979	};
782	};	980	};
783	};	981	};
784
785	$grp
786	}	982	};
		983
		984	$grp
787	}	985	}
788		986
789	=item aio_rmtree $path, $callback->($status)	987	=item aio_rmtree $path, $callback->($status)
790		988
791	Delete a directory tree starting (and including) C<$path>, return the	989	Delete a directory tree starting (and including) C<$path>, return the
…		…
795		993
796	=cut	994	=cut
797		995
798	sub aio_rmtree;	996	sub aio_rmtree;
799	sub aio_rmtree($;$) {	997	sub aio_rmtree($;$) {
800	aio_block {
801	my ($path, $cb) = @_;	998	my ($path, $cb) = @_;
802		999
803	my $pri = aioreq_pri;	1000	my $pri = aioreq_pri;
804	my $grp = aio_group $cb;	1001	my $grp = aio_group $cb;
805		1002
806	aioreq_pri $pri;	1003	aioreq_pri $pri;
807	add $grp aio_scandir $path, 0, sub {	1004	add $grp aio_scandir $path, 0, sub {
808	my ($dirs, $nondirs) = @_;	1005	my ($dirs, $nondirs) = @_;
809		1006
810	my $dirgrp = aio_group sub {	1007	my $dirgrp = aio_group sub {
811	add $grp aio_rmdir $path, sub {	1008	add $grp aio_rmdir $path, sub {
812	$grp->result ($_[0]);	1009	$grp->result ($_[0]);
813	};
814	};	1010	};
815
816	(aioreq_pri $pri), add $dirgrp aio_rmtree "$path/$_" for @$dirs;
817	(aioreq_pri $pri), add $dirgrp aio_unlink "$path/$_" for @$nondirs;
818
819	add $grp $dirgrp;
820	};	1011	};
821		1012
822	$grp	1013	(aioreq_pri $pri), add $dirgrp aio_rmtree "$path/$_" for @$dirs;
		1014	(aioreq_pri $pri), add $dirgrp aio_unlink "$path/$_" for @$nondirs;
		1015
		1016	add $grp $dirgrp;
823	}	1017	};
		1018
		1019	$grp
824	}	1020	}
		1021
		1022	=item aio_sync $callback->($status)
		1023
		1024	Asynchronously call sync and call the callback when finished.
825		1025
826	=item aio_fsync $fh, $callback->($status)	1026	=item aio_fsync $fh, $callback->($status)
827		1027
828	Asynchronously call fsync on the given filehandle and call the callback	1028	Asynchronously call fsync on the given filehandle and call the callback
829	with the fsync result code.	1029	with the fsync result code.
…		…
833	Asynchronously call fdatasync on the given filehandle and call the	1033	Asynchronously call fdatasync on the given filehandle and call the
834	callback with the fdatasync result code.	1034	callback with the fdatasync result code.
835		1035
836	If this call isn't available because your OS lacks it or it couldn't be	1036	If this call isn't available because your OS lacks it or it couldn't be
837	detected, it will be emulated by calling C<fsync> instead.	1037	detected, it will be emulated by calling C<fsync> instead.
		1038
		1039	=item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
		1040
		1041	Sync the data portion of the file specified by C<$offset> and C<$length>
		1042	to disk (but NOT the metadata), by calling the Linux-specific
		1043	sync_file_range call. If sync_file_range is not available or it returns
		1044	ENOSYS, then fdatasync or fsync is being substituted.
		1045
		1046	C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>,
		1047	C<IO::AIO::SYNC_FILE_RANGE_WRITE> and
		1048	C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range
		1049	manpage for details.
		1050
		1051	=item aio_pathsync $path, $callback->($status)
		1052
		1053	This request tries to open, fsync and close the given path. This is a
		1054	composite request intended to sync directories after directory operations
		1055	(E.g. rename). This might not work on all operating systems or have any
		1056	specific effect, but usually it makes sure that directory changes get
		1057	written to disc. It works for anything that can be opened for read-only,
		1058	not just directories.
		1059
		1060	Future versions of this function might fall back to other methods when
		1061	C<fsync> on the directory fails (such as calling C<sync>).
		1062
		1063	Passes C<0> when everything went ok, and C<-1> on error.
		1064
		1065	=cut
		1066
		1067	sub aio_pathsync($;$) {
		1068	my ($path, $cb) = @_;
		1069
		1070	my $pri = aioreq_pri;
		1071	my $grp = aio_group $cb;
		1072
		1073	aioreq_pri $pri;
		1074	add $grp aio_open $path, O_RDONLY, 0, sub {
		1075	my ($fh) = @_;
		1076	if ($fh) {
		1077	aioreq_pri $pri;
		1078	add $grp aio_fsync $fh, sub {
		1079	$grp->result ($_[0]);
		1080
		1081	aioreq_pri $pri;
		1082	add $grp aio_close $fh;
		1083	};
		1084	} else {
		1085	$grp->result (-1);
		1086	}
		1087	};
		1088
		1089	$grp
		1090	}
		1091
		1092	=item aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
		1093
		1094	This is a rather advanced IO::AIO call, which only works on mmap(2)ed
		1095	scalars (see the C<IO::AIO::mmap> function, although it also works on data
		1096	scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the
		1097	scalar must only be modified in-place while an aio operation is pending on
		1098	it).
		1099
		1100	It calls the C<msync> function of your OS, if available, with the memory
		1101	area starting at C<$offset> in the string and ending C<$length> bytes
		1102	later. If C<$length> is negative, counts from the end, and if C<$length>
		1103	is C<undef>, then it goes till the end of the string. The flags can be
		1104	a combination of C<IO::AIO::MS_ASYNC>, C<IO::AIO::MS_INVALIDATE> and
		1105	C<IO::AIO::MS_SYNC>.
		1106
		1107	=item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
		1108
		1109	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
		1110	scalars.
		1111
		1112	It touches (reads or writes) all memory pages in the specified
		1113	range inside the scalar. All caveats and parameters are the same
		1114	as for C<aio_msync>, above, except for flags, which must be either
		1115	C<0> (which reads all pages and ensures they are instantiated) or
		1116	C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and
		1117	writing an octet from it, which dirties the page).
		1118
		1119	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
		1120
		1121	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
		1122	scalars.
		1123
		1124	It reads in all the pages of the underlying storage into memory (if any)
		1125	and locks them, so they are not getting swapped/paged out or removed.
		1126
		1127	If C<$length> is undefined, then the scalar will be locked till the end.
		1128
		1129	On systems that do not implement C<mlock>, this function returns C<-1>
		1130	and sets errno to C<ENOSYS>.
		1131
		1132	Note that the corresponding C<munlock> is synchronous and is
		1133	documented under L<MISCELLANEOUS FUNCTIONS>.
		1134
		1135	Example: open a file, mmap and mlock it - both will be undone when
		1136	C<$data> gets destroyed.
		1137
		1138	open my $fh, "<", $path or die "$path: $!";
		1139	my $data;
		1140	IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh;
		1141	aio_mlock $data; # mlock in background
		1142
		1143	=item aio_mlockall $flags, $callback->($status)
		1144
		1145	Calls the C<mlockall> function with the given C<$flags> (a combination of
		1146	C<IO::AIO::MCL_CURRENT> and C<IO::AIO::MCL_FUTURE>).
		1147
		1148	On systems that do not implement C<mlockall>, this function returns C<-1>
		1149	and sets errno to C<ENOSYS>.
		1150
		1151	Note that the corresponding C<munlockall> is synchronous and is
		1152	documented under L<MISCELLANEOUS FUNCTIONS>.
		1153
		1154	Example: asynchronously lock all current and future pages into memory.
		1155
		1156	aio_mlockall IO::AIO::MCL_FUTURE;
838		1157
839	=item aio_group $callback->(...)	1158	=item aio_group $callback->(...)
840		1159
841	This is a very special aio request: Instead of doing something, it is a	1160	This is a very special aio request: Instead of doing something, it is a
842	container for other aio requests, which is useful if you want to bundle	1161	container for other aio requests, which is useful if you want to bundle
…		…
892	=item cancel $req	1211	=item cancel $req
893		1212
894	Cancels the request, if possible. Has the effect of skipping execution	1213	Cancels the request, if possible. Has the effect of skipping execution
895	when entering the B<execute> state and skipping calling the callback when	1214	when entering the B<execute> state and skipping calling the callback when
896	entering the the B<result> state, but will leave the request otherwise	1215	entering the the B<result> state, but will leave the request otherwise
897	untouched. That means that requests that currently execute will not be	1216	untouched (with the exception of readdir). That means that requests that
898	stopped and resources held by the request will not be freed prematurely.	1217	currently execute will not be stopped and resources held by the request
		1218	will not be freed prematurely.
899		1219
900	=item cb $req $callback->(...)	1220	=item cb $req $callback->(...)
901		1221
902	Replace (or simply set) the callback registered to the request.	1222	Replace (or simply set) the callback registered to the request.
903		1223
…		…
954	Their lifetime, simplified, looks like this: when they are empty, they	1274	Their lifetime, simplified, looks like this: when they are empty, they
955	will finish very quickly. If they contain only requests that are in the	1275	will finish very quickly. If they contain only requests that are in the
956	C<done> state, they will also finish. Otherwise they will continue to	1276	C<done> state, they will also finish. Otherwise they will continue to
957	exist.	1277	exist.
958		1278
959	That means after creating a group you have some time to add requests. And	1279	That means after creating a group you have some time to add requests
960	in the callbacks of those requests, you can add further requests to the	1280	(precisely before the callback has been invoked, which is only done within
961	group. And only when all those requests have finished will the the group	1281	the C<poll_cb>). And in the callbacks of those requests, you can add
962	itself finish.	1282	further requests to the group. And only when all those requests have
		1283	finished will the the group itself finish.
963		1284
964	=over 4	1285	=over 4
965		1286
966	=item add $grp ...	1287	=item add $grp ...
967		1288
…		…
976	=item $grp->cancel_subs	1297	=item $grp->cancel_subs
977		1298
978	Cancel all subrequests and clears any feeder, but not the group request	1299	Cancel all subrequests and clears any feeder, but not the group request
979	itself. Useful when you queued a lot of events but got a result early.	1300	itself. Useful when you queued a lot of events but got a result early.
980		1301
		1302	The group request will finish normally (you cannot add requests to the
		1303	group).
		1304
981	=item $grp->result (...)	1305	=item $grp->result (...)
982		1306
983	Set the result value(s) that will be passed to the group callback when all	1307	Set the result value(s) that will be passed to the group callback when all
984	subrequests have finished and set thre groups errno to the current value	1308	subrequests have finished and set the groups errno to the current value
985	of errno (just like calling C<errno> without an error number). By default,	1309	of errno (just like calling C<errno> without an error number). By default,
986	no argument will be passed and errno is zero.	1310	no argument will be passed and errno is zero.
987		1311
988	=item $grp->errno ([$errno])	1312	=item $grp->errno ([$errno])
989		1313
…		…
1000	=item feed $grp $callback->($grp)	1324	=item feed $grp $callback->($grp)
1001		1325
1002	Sets a feeder/generator on this group: every group can have an attached	1326	Sets a feeder/generator on this group: every group can have an attached
1003	generator that generates requests if idle. The idea behind this is that,	1327	generator that generates requests if idle. The idea behind this is that,
1004	although you could just queue as many requests as you want in a group,	1328	although you could just queue as many requests as you want in a group,
1005	this might starve other requests for a potentially long time. For	1329	this might starve other requests for a potentially long time. For example,
1006	example, C<aio_scandir> might generate hundreds of thousands C<aio_stat>	1330	C<aio_scandir> might generate hundreds of thousands C<aio_stat> requests,
1007	requests, delaying any later requests for a long time.	1331	delaying any later requests for a long time.
1008		1332
1009	To avoid this, and allow incremental generation of requests, you can	1333	To avoid this, and allow incremental generation of requests, you can
1010	instead a group and set a feeder on it that generates those requests. The	1334	instead a group and set a feeder on it that generates those requests. The
1011	feed callback will be called whenever there are few enough (see C<limit>,	1335	feed callback will be called whenever there are few enough (see C<limit>,
1012	below) requests active in the group itself and is expected to queue more	1336	below) requests active in the group itself and is expected to queue more
…		…
1016	not impose any limits).	1340	not impose any limits).
1017		1341
1018	If the feed does not queue more requests when called, it will be	1342	If the feed does not queue more requests when called, it will be
1019	automatically removed from the group.	1343	automatically removed from the group.
1020		1344
1021	If the feed limit is C<0>, it will be set to C<2> automatically.	1345	If the feed limit is C<0> when this method is called, it will be set to
		1346	C<2> automatically.
1022		1347
1023	Example:	1348	Example:
1024		1349
1025	# stat all files in @files, but only ever use four aio requests concurrently:	1350	# stat all files in @files, but only ever use four aio requests concurrently:
1026		1351
…		…
1038	Sets the feeder limit for the group: The feeder will be called whenever	1363	Sets the feeder limit for the group: The feeder will be called whenever
1039	the group contains less than this many requests.	1364	the group contains less than this many requests.
1040		1365
1041	Setting the limit to C<0> will pause the feeding process.	1366	Setting the limit to C<0> will pause the feeding process.
1042		1367
		1368	The default value for the limit is C<0>, but note that setting a feeder
		1369	automatically bumps it up to C<2>.
		1370
1043	=back	1371	=back
1044		1372
1045	=head2 SUPPORT FUNCTIONS	1373	=head2 SUPPORT FUNCTIONS
1046		1374
1047	=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION	1375	=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION
…		…
1049	=over 4	1377	=over 4
1050		1378
1051	=item $fileno = IO::AIO::poll_fileno	1379	=item $fileno = IO::AIO::poll_fileno
1052		1380
1053	Return the I<request result pipe file descriptor>. This filehandle must be	1381	Return the I<request result pipe file descriptor>. This filehandle must be
1054	polled for reading by some mechanism outside this module (e.g. Event or	1382	polled for reading by some mechanism outside this module (e.g. EV, Glib,
1055	select, see below or the SYNOPSIS). If the pipe becomes readable you have	1383	select and so on, see below or the SYNOPSIS). If the pipe becomes readable
1056	to call C<poll_cb> to check the results.	1384	you have to call C<poll_cb> to check the results.
1057		1385
1058	See C<poll_cb> for an example.	1386	See C<poll_cb> for an example.
1059		1387
1060	=item IO::AIO::poll_cb	1388	=item IO::AIO::poll_cb
1061		1389
1062	Process some outstanding events on the result pipe. You have to call this	1390	Process some outstanding events on the result pipe. You have to call this
1063	regularly. Returns the number of events processed. Returns immediately	1391	regularly. Returns C<0> if all events could be processed, or C<-1> if it
		1392	returned earlier for whatever reason. Returns immediately when no events
1064	when no events are outstanding. The amount of events processed depends on	1393	are outstanding. The amount of events processed depends on the settings of
1065	the settings of C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>.	1394	C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>.
1066		1395
1067	If not all requests were processed for whatever reason, the filehandle	1396	If not all requests were processed for whatever reason, the filehandle
1068	will still be ready when C<poll_cb> returns.	1397	will still be ready when C<poll_cb> returns, so normally you don't have to
		1398	do anything special to have it called later.
1069		1399
1070	Example: Install an Event watcher that automatically calls	1400	Example: Install an Event watcher that automatically calls
1071	IO::AIO::poll_cb with high priority:	1401	IO::AIO::poll_cb with high priority (more examples can be found in the
		1402	SYNOPSIS section, at the top of this document):
1072		1403
1073	Event->io (fd => IO::AIO::poll_fileno,	1404	Event->io (fd => IO::AIO::poll_fileno,
1074	poll => 'r', async => 1,	1405	poll => 'r', async => 1,
1075	cb => \&IO::AIO::poll_cb);	1406	cb => \&IO::AIO::poll_cb);
		1407
		1408	=item IO::AIO::poll_wait
		1409
		1410	If there are any outstanding requests and none of them in the result
		1411	phase, wait till the result filehandle becomes ready for reading (simply
		1412	does a C<select> on the filehandle. This is useful if you want to
		1413	synchronously wait for some requests to finish).
		1414
		1415	See C<nreqs> for an example.
		1416
		1417	=item IO::AIO::poll
		1418
		1419	Waits until some requests have been handled.
		1420
		1421	Returns the number of requests processed, but is otherwise strictly
		1422	equivalent to:
		1423
		1424	IO::AIO::poll_wait, IO::AIO::poll_cb
		1425
		1426	=item IO::AIO::flush
		1427
		1428	Wait till all outstanding AIO requests have been handled.
		1429
		1430	Strictly equivalent to:
		1431
		1432	IO::AIO::poll_wait, IO::AIO::poll_cb
		1433	while IO::AIO::nreqs;
1076		1434
1077	=item IO::AIO::max_poll_reqs $nreqs	1435	=item IO::AIO::max_poll_reqs $nreqs
1078		1436
1079	=item IO::AIO::max_poll_time $seconds	1437	=item IO::AIO::max_poll_time $seconds
1080		1438
…		…
1105	# use a low priority so other tasks have priority	1463	# use a low priority so other tasks have priority
1106	Event->io (fd => IO::AIO::poll_fileno,	1464	Event->io (fd => IO::AIO::poll_fileno,
1107	poll => 'r', nice => 1,	1465	poll => 'r', nice => 1,
1108	cb => &IO::AIO::poll_cb);	1466	cb => &IO::AIO::poll_cb);
1109		1467
1110	=item IO::AIO::poll_wait
1111
1112	If there are any outstanding requests and none of them in the result
1113	phase, wait till the result filehandle becomes ready for reading (simply
1114	does a C<select> on the filehandle. This is useful if you want to
1115	synchronously wait for some requests to finish).
1116
1117	See C<nreqs> for an example.
1118
1119	=item IO::AIO::poll
1120
1121	Waits until some requests have been handled.
1122
1123	Returns the number of requests processed, but is otherwise strictly
1124	equivalent to:
1125
1126	IO::AIO::poll_wait, IO::AIO::poll_cb
1127
1128	=item IO::AIO::flush
1129
1130	Wait till all outstanding AIO requests have been handled.
1131
1132	Strictly equivalent to:
1133
1134	IO::AIO::poll_wait, IO::AIO::poll_cb
1135	while IO::AIO::nreqs;
1136
1137	=back	1468	=back
1138		1469
1139	=head3 CONTROLLING THE NUMBER OF THREADS	1470	=head3 CONTROLLING THE NUMBER OF THREADS
1140		1471
1141	=over	1472	=over
…		…
1187		1518
1188	The default is probably ok in most situations, especially if thread	1519	The default is probably ok in most situations, especially if thread
1189	creation is fast. If thread creation is very slow on your system you might	1520	creation is fast. If thread creation is very slow on your system you might
1190	want to use larger values.	1521	want to use larger values.
1191		1522
1192	=item $oldmaxreqs = IO::AIO::max_outstanding $maxreqs	1523	=item IO::AIO::max_outstanding $maxreqs
1193		1524
1194	This is a very bad function to use in interactive programs because it	1525	This is a very bad function to use in interactive programs because it
1195	blocks, and a bad way to reduce concurrency because it is inexact: Better	1526	blocks, and a bad way to reduce concurrency because it is inexact: Better
1196	use an C<aio_group> together with a feed callback.	1527	use an C<aio_group> together with a feed callback.
1197		1528
1198	Sets the maximum number of outstanding requests to C<$nreqs>. If you	1529	Sets the maximum number of outstanding requests to C<$nreqs>. If you
1199	to queue up more than this number of requests, the next call to the	1530	do queue up more than this number of requests, the next call to the
1200	C<poll_cb> (and C<poll_some> and other functions calling C<poll_cb>)	1531	C<poll_cb> (and C<poll_some> and other functions calling C<poll_cb>)
1201	function will block until the limit is no longer exceeded.	1532	function will block until the limit is no longer exceeded.
1202		1533
1203	The default value is very large, so there is no practical limit on the	1534	The default value is very large, so there is no practical limit on the
1204	number of outstanding requests.	1535	number of outstanding requests.
1205		1536
1206	You can still queue as many requests as you want. Therefore,	1537	You can still queue as many requests as you want. Therefore,
1207	C<max_oustsanding> is mainly useful in simple scripts (with low values) or	1538	C<max_outstanding> is mainly useful in simple scripts (with low values) or
1208	as a stop gap to shield against fatal memory overflow (with large values).	1539	as a stop gap to shield against fatal memory overflow (with large values).
1209		1540
1210	=back	1541	=back
1211		1542
1212	=head3 STATISTICAL INFORMATION	1543	=head3 STATISTICAL INFORMATION
…		…
1233	Returns the number of requests currently in the pending state (executed,	1564	Returns the number of requests currently in the pending state (executed,
1234	but not yet processed by poll_cb).	1565	but not yet processed by poll_cb).
1235		1566
1236	=back	1567	=back
1237		1568
		1569	=head3 MISCELLANEOUS FUNCTIONS
		1570
		1571	IO::AIO implements some functions that might be useful, but are not
		1572	asynchronous.
		1573
		1574	=over 4
		1575
		1576	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
		1577
		1578	Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>,
		1579	but is blocking (this makes most sense if you know the input data is
		1580	likely cached already and the output filehandle is set to non-blocking
		1581	operations).
		1582
		1583	Returns the number of bytes copied, or C<-1> on error.
		1584
		1585	=item IO::AIO::fadvise $fh, $offset, $len, $advice
		1586
		1587	Simply calls the C<posix_fadvise> function (see its
		1588	manpage for details). The following advice constants are
		1589	avaiable: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>,
		1590	C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>,
		1591	C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>.
		1592
		1593	On systems that do not implement C<posix_fadvise>, this function returns
		1594	ENOSYS, otherwise the return value of C<posix_fadvise>.
		1595
		1596	=item IO::AIO::madvise $scalar, $offset, $len, $advice
		1597
		1598	Simply calls the C<posix_madvise> function (see its
		1599	manpage for details). The following advice constants are
		1600	avaiable: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,
		1601	C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>.
		1602
		1603	On systems that do not implement C<posix_madvise>, this function returns
		1604	ENOSYS, otherwise the return value of C<posix_madvise>.
		1605
		1606	=item IO::AIO::mprotect $scalar, $offset, $len, $protect
		1607
		1608	Simply calls the C<mprotect> function on the preferably AIO::mmap'ed
		1609	$scalar (see its manpage for details). The following protect
		1610	constants are avaiable: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,
		1611	C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.
		1612
		1613	On systems that do not implement C<mprotect>, this function returns
		1614	ENOSYS, otherwise the return value of C<mprotect>.
		1615
		1616	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]
		1617
		1618	Memory-maps a file (or anonymous memory range) and attaches it to the
		1619	given C<$scalar>, which will act like a string scalar.
		1620
		1621	The only operations allowed on the scalar are C<substr>/C<vec> that don't
		1622	change the string length, and most read-only operations such as copying it
		1623	or searching it with regexes and so on.
		1624
		1625	Anything else is unsafe and will, at best, result in memory leaks.
		1626
		1627	The memory map associated with the C<$scalar> is automatically removed
		1628	when the C<$scalar> is destroyed, or when the C<IO::AIO::mmap> or
		1629	C<IO::AIO::munmap> functions are called.
		1630
		1631	This calls the C<mmap>(2) function internally. See your system's manual
		1632	page for details on the C<$length>, C<$prot> and C<$flags> parameters.
		1633
		1634	The C<$length> must be larger than zero and smaller than the actual
		1635	filesize.
		1636
		1637	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,
		1638	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,
		1639
		1640	C<$flags> can be a combination of C<IO::AIO::MAP_SHARED> or
		1641	C<IO::AIO::MAP_PRIVATE>, or a number of system-specific flags (when
		1642	not available, the are defined as 0): C<IO::AIO::MAP_ANONYMOUS>
		1643	(which is set to C<MAP_ANON> if your system only provides this
		1644	constant), C<IO::AIO::MAP_HUGETLB>, C<IO::AIO::MAP_LOCKED>,
		1645	C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or
		1646	C<IO::AIO::MAP_NONBLOCK>
		1647
		1648	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.
		1649
		1650	C<$offset> is the offset from the start of the file - it generally must be
		1651	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.
		1652
		1653	Example:
		1654
		1655	use Digest::MD5;
		1656	use IO::AIO;
		1657
		1658	open my $fh, "<verybigfile"
		1659	or die "$!";
		1660
		1661	IO::AIO::mmap my $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh
		1662	or die "verybigfile: $!";
		1663
		1664	my $fast_md5 = md5 $data;
		1665
		1666	=item IO::AIO::munmap $scalar
		1667
		1668	Removes a previous mmap and undefines the C<$scalar>.
		1669
		1670	=item IO::AIO::munlock $scalar, $offset = 0, $length = undef
		1671
		1672	Calls the C<munlock> function, undoing the effects of a previous
		1673	C<aio_mlock> call (see its description for details).
		1674
		1675	=item IO::AIO::munlockall
		1676
		1677	Calls the C<munlockall> function.
		1678
		1679	On systems that do not implement C<munlockall>, this function returns
		1680	ENOSYS, otherwise the return value of C<munlockall>.
		1681
		1682	=back
		1683
1238	=cut	1684	=cut
1239		1685
1240	# support function to convert a fd into a perl filehandle
1241	sub _fd2fh {
1242	return undef if $_[0] < 0;
1243
1244	# try to generate nice filehandles
1245	my $sym = "IO::AIO::fd#$_[0]";
1246	local *$sym;
1247
1248	open *$sym, "+<&=$_[0]" # usually works under any unix
1249	or open *$sym, "<&=$_[0]" # cygwin needs this
1250	or open *$sym, ">&=$_[0]" # or this
1251	or return undef;
1252
1253	*$sym
1254	}
1255
1256	min_parallel 8;	1686	min_parallel 8;
1257		1687
1258	END { flush }	1688	END { flush }
1259		1689
1260	1;	1690	1;
		1691
		1692	=head1 EVENT LOOP INTEGRATION
		1693
		1694	It is recommended to use L<AnyEvent::AIO> to integrate IO::AIO
		1695	automatically into many event loops:
		1696
		1697	# AnyEvent integration (EV, Event, Glib, Tk, POE, urxvt, pureperl...)
		1698	use AnyEvent::AIO;
		1699
		1700	You can also integrate IO::AIO manually into many event loops, here are
		1701	some examples of how to do this:
		1702
		1703	# EV integration
		1704	my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
		1705
		1706	# Event integration
		1707	Event->io (fd => IO::AIO::poll_fileno,
		1708	poll => 'r',
		1709	cb => \&IO::AIO::poll_cb);
		1710
		1711	# Glib/Gtk2 integration
		1712	add_watch Glib::IO IO::AIO::poll_fileno,
		1713	in => sub { IO::AIO::poll_cb; 1 };
		1714
		1715	# Tk integration
		1716	Tk::Event::IO->fileevent (IO::AIO::poll_fileno, "",
		1717	readable => \&IO::AIO::poll_cb);
		1718
		1719	# Danga::Socket integration
		1720	Danga::Socket->AddOtherFds (IO::AIO::poll_fileno =>
		1721	\&IO::AIO::poll_cb);
1261		1722
1262	=head2 FORK BEHAVIOUR	1723	=head2 FORK BEHAVIOUR
1263		1724
1264	This module should do "the right thing" when the process using it forks:	1725	This module should do "the right thing" when the process using it forks:
1265		1726
…		…
1283	bytes of memory. In addition, stat requests need a stat buffer (possibly	1744	bytes of memory. In addition, stat requests need a stat buffer (possibly
1284	a few hundred bytes), readdir requires a result buffer and so on. Perl	1745	a few hundred bytes), readdir requires a result buffer and so on. Perl
1285	scalars and other data passed into aio requests will also be locked and	1746	scalars and other data passed into aio requests will also be locked and
1286	will consume memory till the request has entered the done state.	1747	will consume memory till the request has entered the done state.
1287		1748
1288	This is now awfully much, so queuing lots of requests is not usually a	1749	This is not awfully much, so queuing lots of requests is not usually a
1289	problem.	1750	problem.
1290		1751
1291	Per-thread usage:	1752	Per-thread usage:
1292		1753
1293	In the execution phase, some aio requests require more memory for	1754	In the execution phase, some aio requests require more memory for
…		…
1298		1759
1299	Known bugs will be fixed in the next release.	1760	Known bugs will be fixed in the next release.
1300		1761
1301	=head1 SEE ALSO	1762	=head1 SEE ALSO
1302		1763
1303	L<Coro::AIO>.	1764	L<AnyEvent::AIO> for easy integration into event loops, L<Coro::AIO> for a
		1765	more natural syntax.
1304		1766
1305	=head1 AUTHOR	1767	=head1 AUTHOR
1306		1768
1307	Marc Lehmann <schmorp@schmorp.de>	1769	Marc Lehmann <schmorp@schmorp.de>
1308	http://home.schmorp.de/	1770	http://home.schmorp.de/

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