ViewVC Help

View File | Revision Log | Show Annotations | Download File

/cvs/IO-AIO/AIO.pm

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.96 by root, Fri Dec 22 04:05:50 2006 UTC vs.
Revision 1.181 by root, Tue May 4 21:14:01 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 = '2.21';	173	our $VERSION = '3.65';
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
200	aio_move aio_copy aio_group aio_nop aio_mknod);	178	aio_fdatasync aio_sync_file_range aio_pathsync aio_readahead
		179	aio_rename aio_link aio_move aio_copy aio_group
		180	aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown
		181	aio_chmod aio_utime aio_truncate
		182	aio_msync aio_mtouch aio_statvfs);
		183
201	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice aio_block));	184	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));
202	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush	185	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush
203	min_parallel max_parallel max_idle	186	min_parallel max_parallel max_idle
204	nreqs nready npending nthreads	187	nreqs nready npending nthreads
205	max_poll_time max_poll_reqs);	188	max_poll_time max_poll_reqs
		189	sendfile fadvise);
		190
		191	push @AIO_REQ, qw(aio_busy); # not exported
206		192
207	@IO::AIO::GRP::ISA = 'IO::AIO::REQ';	193	@IO::AIO::GRP::ISA = 'IO::AIO::REQ';
208		194
209	require XSLoader;	195	require XSLoader;
210	XSLoader::load ("IO::AIO", $VERSION);	196	XSLoader::load ("IO::AIO", $VERSION);
211	}	197	}
212		198
213	=head1 FUNCTIONS	199	=head1 FUNCTIONS
		200
		201	=head2 QUICK OVERVIEW
		202
		203	This section simply lists the prototypes of the most important functions
		204	for quick reference. See the following sections for function-by-function
		205	documentation.
		206
		207	aio_open $pathname, $flags, $mode, $callback->($fh)
		208	aio_close $fh, $callback->($status)
		209	aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
		210	aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
		211	aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
		212	aio_readahead $fh,$offset,$length, $callback->($retval)
		213	aio_stat $fh_or_path, $callback->($status)
		214	aio_lstat $fh, $callback->($status)
		215	aio_statvfs $fh_or_path, $callback->($statvfs)
		216	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
		217	aio_chown $fh_or_path, $uid, $gid, $callback->($status)
		218	aio_truncate $fh_or_path, $offset, $callback->($status)
		219	aio_chmod $fh_or_path, $mode, $callback->($status)
		220	aio_unlink $pathname, $callback->($status)
		221	aio_mknod $path, $mode, $dev, $callback->($status)
		222	aio_link $srcpath, $dstpath, $callback->($status)
		223	aio_symlink $srcpath, $dstpath, $callback->($status)
		224	aio_readlink $path, $callback->($link)
		225	aio_rename $srcpath, $dstpath, $callback->($status)
		226	aio_mkdir $pathname, $mode, $callback->($status)
		227	aio_rmdir $pathname, $callback->($status)
		228	aio_readdir $pathname, $callback->($entries)
		229	aio_readdirx $pathname, $flags, $callback->($entries, $flags)
		230	IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST
		231	IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN
		232	aio_load $path, $data, $callback->($status)
		233	aio_copy $srcpath, $dstpath, $callback->($status)
		234	aio_move $srcpath, $dstpath, $callback->($status)
		235	aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
		236	aio_rmtree $path, $callback->($status)
		237	aio_sync $callback->($status)
		238	aio_fsync $fh, $callback->($status)
		239	aio_fdatasync $fh, $callback->($status)
		240	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
		241	aio_pathsync $path, $callback->($status)
		242	aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
		243	aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
		244	aio_group $callback->(...)
		245	aio_nop $callback->()
		246
		247	$prev_pri = aioreq_pri [$pri]
		248	aioreq_nice $pri_adjust
		249
		250	IO::AIO::poll_wait
		251	IO::AIO::poll_cb
		252	IO::AIO::poll
		253	IO::AIO::flush
		254	IO::AIO::max_poll_reqs $nreqs
		255	IO::AIO::max_poll_time $seconds
		256	IO::AIO::min_parallel $nthreads
		257	IO::AIO::max_parallel $nthreads
		258	IO::AIO::max_idle $nthreads
		259	IO::AIO::max_outstanding $maxreqs
		260	IO::AIO::nreqs
		261	IO::AIO::nready
		262	IO::AIO::npending
		263
		264	IO::AIO::sendfile $ofh, $ifh, $offset, $count
		265	IO::AIO::fadvise $fh, $offset, $len, $advice
		266	IO::AIO::mlockall $flags
		267	IO::AIO::munlockall
214		268
215	=head2 AIO REQUEST FUNCTIONS	269	=head2 AIO REQUEST FUNCTIONS
216		270
217	All the C<aio_*> calls are more or less thin wrappers around the syscall	271	All the C<aio_*> calls are more or less thin wrappers around the syscall
218	with the same name (sans C<aio_>). The arguments are similar or identical,	272	with the same name (sans C<aio_>). The arguments are similar or identical,
219	and they all accept an additional (and optional) C<$callback> argument	273	and they all accept an additional (and optional) C<$callback> argument
220	which must be a code reference. This code reference will get called with	274	which must be a code reference. This code reference will get called with
221	the syscall return code (e.g. most syscalls return C<-1> on error, unlike	275	the syscall return code (e.g. most syscalls return C<-1> on error, unlike
222	perl, which usually delivers "false") as it's sole argument when the given	276	perl, which usually delivers "false") as its sole argument after the given
223	syscall has been executed asynchronously.	277	syscall has been executed asynchronously.
224		278
225	All functions expecting a filehandle keep a copy of the filehandle	279	All functions expecting a filehandle keep a copy of the filehandle
226	internally until the request has finished.	280	internally until the request has finished.
227		281
…		…
241	your pathnames to the locale (or other) encoding in effect in the user	295	your pathnames to the locale (or other) encoding in effect in the user
242	environment, d) use Glib::filename_from_unicode on unicode filenames or e)	296	environment, d) use Glib::filename_from_unicode on unicode filenames or e)
243	use something else to ensure your scalar has the correct contents.	297	use something else to ensure your scalar has the correct contents.
244		298
245	This works, btw. independent of the internal UTF-8 bit, which IO::AIO	299	This works, btw. independent of the internal UTF-8 bit, which IO::AIO
246	handles correctly wether it is set or not.	300	handles correctly whether it is set or not.
247		301
248	=over 4	302	=over 4
249		303
250	=item $prev_pri = aioreq_pri [$pri]	304	=item $prev_pri = aioreq_pri [$pri]
251		305
…		…
271	aio_read $_[0], ..., sub {	325	aio_read $_[0], ..., sub {
272	...	326	...
273	};	327	};
274	};	328	};
275		329
		330
276	=item aioreq_nice $pri_adjust	331	=item aioreq_nice $pri_adjust
277		332
278	Similar to C<aioreq_pri>, but subtracts the given value from the current	333	Similar to C<aioreq_pri>, but subtracts the given value from the current
279	priority, so the effect is cumulative.	334	priority, so the effect is cumulative.
		335
280		336
281	=item aio_open $pathname, $flags, $mode, $callback->($fh)	337	=item aio_open $pathname, $flags, $mode, $callback->($fh)
282		338
283	Asynchronously open or create a file and call the callback with a newly	339	Asynchronously open or create a file and call the callback with a newly
284	created filehandle for the file.	340	created filehandle for the file.
…		…
290	list. They are the same as used by C<sysopen>.	346	list. They are the same as used by C<sysopen>.
291		347
292	Likewise, C<$mode> specifies the mode of the newly created file, if it	348	Likewise, C<$mode> specifies the mode of the newly created file, if it
293	didn't exist and C<O_CREAT> has been given, just like perl's C<sysopen>,	349	didn't exist and C<O_CREAT> has been given, just like perl's C<sysopen>,
294	except that it is mandatory (i.e. use C<0> if you don't create new files,	350	except that it is mandatory (i.e. use C<0> if you don't create new files,
295	and C<0666> or C<0777> if you do).	351	and C<0666> or C<0777> if you do). Note that the C<$mode> will be modified
		352	by the umask in effect then the request is being executed, so better never
		353	change the umask.
296		354
297	Example:	355	Example:
298		356
299	aio_open "/etc/passwd", O_RDONLY, 0, sub {	357	aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub {
300	if ($_[0]) {	358	if ($_[0]) {
301	print "open successful, fh is $_[0]\n";	359	print "open successful, fh is $_[0]\n";
302	...	360	...
303	} else {	361	} else {
304	die "open failed: $!\n";	362	die "open failed: $!\n";
305	}	363	}
306	};	364	};
307		365
		366
308	=item aio_close $fh, $callback->($status)	367	=item aio_close $fh, $callback->($status)
309		368
310	Asynchronously close a file and call the callback with the result	369	Asynchronously close a file and call the callback with the result
311	code. I<WARNING:> although accepted, you should not pass in a perl	370	code.
312	filehandle here, as perl will likely close the file descriptor another
313	time when the filehandle is destroyed. Normally, you can safely call perls
314	C<close> or just let filehandles go out of scope.
315		371
316	This is supposed to be a bug in the API, so that might change. It's	372	Unfortunately, you can't do this to perl. Perl I<insists> very strongly on
317	therefore best to avoid this function.	373	closing the file descriptor associated with the filehandle itself.
		374
		375	Therefore, C<aio_close> will not close the filehandle - instead it will
		376	use dup2 to overwrite the file descriptor with the write-end of a pipe
		377	(the pipe fd will be created on demand and will be cached).
		378
		379	Or in other words: the file descriptor will be closed, but it will not be
		380	free for reuse until the perl filehandle is closed.
		381
		382	=cut
318		383
319	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	384	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
320		385
321	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	386	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
322		387
323	Reads or writes C<length> bytes from the specified C<fh> and C<offset>	388	Reads or writes C<$length> bytes from or to the specified C<$fh> and
324	into the scalar given by C<data> and offset C<dataoffset> and calls the	389	C<$offset> into the scalar given by C<$data> and offset C<$dataoffset>
325	callback without the actual number of bytes read (or -1 on error, just	390	and calls the callback without the actual number of bytes read (or -1 on
326	like the syscall).	391	error, just like the syscall).
		392
		393	C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to
		394	offset plus the actual number of bytes read.
		395
		396	If C<$offset> is undefined, then the current file descriptor offset will
		397	be used (and updated), otherwise the file descriptor offset will not be
		398	changed by these calls.
		399
		400	If C<$length> is undefined in C<aio_write>, use the remaining length of
		401	C<$data>.
		402
		403	If C<$dataoffset> is less than zero, it will be counted from the end of
		404	C<$data>.
327		405
328	The C<$data> scalar I<MUST NOT> be modified in any way while the request	406	The C<$data> scalar I<MUST NOT> be modified in any way while the request
329	is outstanding. Modifying it can result in segfaults or WW3 (if the	407	is outstanding. Modifying it can result in segfaults or World War III (if
330	necessary/optional hardware is installed).	408	the necessary/optional hardware is installed).
331		409
332	Example: Read 15 bytes at offset 7 into scalar C<$buffer>, starting at	410	Example: Read 15 bytes at offset 7 into scalar C<$buffer>, starting at
333	offset C<0> within the scalar:	411	offset C<0> within the scalar:
334		412
335	aio_read $fh, 7, 15, $buffer, 0, sub {	413	aio_read $fh, 7, 15, $buffer, 0, sub {
336	$_[0] > 0 or die "read error: $!";	414	$_[0] > 0 or die "read error: $!";
337	print "read $_[0] bytes: <$buffer>\n";	415	print "read $_[0] bytes: <$buffer>\n";
338	};	416	};
		417
339		418
340	=item aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)	419	=item aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
341		420
342	Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts	421	Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts
343	reading at byte offset C<$in_offset>, and starts writing at the current	422	reading at byte offset C<$in_offset>, and starts writing at the current
…		…
345	than one C<aio_sendfile> per C<$out_fh>, as they will interfere with each	424	than one C<aio_sendfile> per C<$out_fh>, as they will interfere with each
346	other.	425	other.
347		426
348	This call tries to make use of a native C<sendfile> syscall to provide	427	This call tries to make use of a native C<sendfile> syscall to provide
349	zero-copy operation. For this to work, C<$out_fh> should refer to a	428	zero-copy operation. For this to work, C<$out_fh> should refer to a
350	socket, and C<$in_fh> should refer to mmap'able file.	429	socket, and C<$in_fh> should refer to an mmap'able file.
351		430
352	If the native sendfile call fails or is not implemented, it will be	431	If a native sendfile cannot be found or it fails with C<ENOSYS>,
		432	C<ENOTSUP>, C<EOPNOTSUPP>, C<EAFNOSUPPORT>, C<EPROTOTYPE> or C<ENOTSOCK>,
353	emulated, so you can call C<aio_sendfile> on any type of filehandle	433	it will be emulated, so you can call C<aio_sendfile> on any type of
354	regardless of the limitations of the operating system.	434	filehandle regardless of the limitations of the operating system.
355		435
356	Please note, however, that C<aio_sendfile> can read more bytes from	436	Please note, however, that C<aio_sendfile> can read more bytes from
357	C<$in_fh> than are written, and there is no way to find out how many	437	C<$in_fh> than are written, and there is no way to find out how many
358	bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only	438	bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only
359	provides the number of bytes written to C<$out_fh>. Only if the result	439	provides the number of bytes written to C<$out_fh>. Only if the result
360	value equals C<$length> one can assume that C<$length> bytes have been	440	value equals C<$length> one can assume that C<$length> bytes have been
361	read.	441	read.
		442
362		443
363	=item aio_readahead $fh,$offset,$length, $callback->($retval)	444	=item aio_readahead $fh,$offset,$length, $callback->($retval)
364		445
365	C<aio_readahead> populates the page cache with data from a file so that	446	C<aio_readahead> populates the page cache with data from a file so that
366	subsequent reads from that file will not block on disk I/O. The C<$offset>	447	subsequent reads from that file will not block on disk I/O. The C<$offset>
…		…
372	file. The current file offset of the file is left unchanged.	453	file. The current file offset of the file is left unchanged.
373		454
374	If that syscall doesn't exist (likely if your OS isn't Linux) it will be	455	If that syscall doesn't exist (likely if your OS isn't Linux) it will be
375	emulated by simply reading the data, which would have a similar effect.	456	emulated by simply reading the data, which would have a similar effect.
376		457
		458
377	=item aio_stat $fh_or_path, $callback->($status)	459	=item aio_stat $fh_or_path, $callback->($status)
378		460
379	=item aio_lstat $fh, $callback->($status)	461	=item aio_lstat $fh, $callback->($status)
380		462
381	Works like perl's C<stat> or C<lstat> in void context. The callback will	463	Works like perl's C<stat> or C<lstat> in void context. The callback will
…		…
394	aio_stat "/etc/passwd", sub {	476	aio_stat "/etc/passwd", sub {
395	$_[0] and die "stat failed: $!";	477	$_[0] and die "stat failed: $!";
396	print "size is ", -s _, "\n";	478	print "size is ", -s _, "\n";
397	};	479	};
398		480
		481
		482	=item aio_statvfs $fh_or_path, $callback->($statvfs)
		483
		484	Works like the POSIX C<statvfs> or C<fstatvfs> syscalls, depending on
		485	whether a file handle or path was passed.
		486
		487	On success, the callback is passed a hash reference with the following
		488	members: C<bsize>, C<frsize>, C<blocks>, C<bfree>, C<bavail>, C<files>,
		489	C<ffree>, C<favail>, C<fsid>, C<flag> and C<namemax>. On failure, C<undef>
		490	is passed.
		491
		492	The following POSIX IO::AIO::ST_* constants are defined: C<ST_RDONLY> and
		493	C<ST_NOSUID>.
		494
		495	The following non-POSIX IO::AIO::ST_* flag masks are defined to
		496	their correct value when available, or to C<0> on systems that do
		497	not support them: C<ST_NODEV>, C<ST_NOEXEC>, C<ST_SYNCHRONOUS>,
		498	C<ST_MANDLOCK>, C<ST_WRITE>, C<ST_APPEND>, C<ST_IMMUTABLE>, C<ST_NOATIME>,
		499	C<ST_NODIRATIME> and C<ST_RELATIME>.
		500
		501	Example: stat C</wd> and dump out the data if successful.
		502
		503	aio_statvfs "/wd", sub {
		504	my $f = $_[0]
		505	or die "statvfs: $!";
		506
		507	use Data::Dumper;
		508	say Dumper $f;
		509	};
		510
		511	# result:
		512	{
		513	bsize => 1024,
		514	bfree => 4333064312,
		515	blocks => 10253828096,
		516	files => 2050765568,
		517	flag => 4096,
		518	favail => 2042092649,
		519	bavail => 4333064312,
		520	ffree => 2042092649,
		521	namemax => 255,
		522	frsize => 1024,
		523	fsid => 1810
		524	}
		525
		526
		527	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
		528
		529	Works like perl's C<utime> function (including the special case of $atime
		530	and $mtime being undef). Fractional times are supported if the underlying
		531	syscalls support them.
		532
		533	When called with a pathname, uses utimes(2) if available, otherwise
		534	utime(2). If called on a file descriptor, uses futimes(2) if available,
		535	otherwise returns ENOSYS, so this is not portable.
		536
		537	Examples:
		538
		539	# set atime and mtime to current time (basically touch(1)):
		540	aio_utime "path", undef, undef;
		541	# set atime to current time and mtime to beginning of the epoch:
		542	aio_utime "path", time, undef; # undef==0
		543
		544
		545	=item aio_chown $fh_or_path, $uid, $gid, $callback->($status)
		546
		547	Works like perl's C<chown> function, except that C<undef> for either $uid
		548	or $gid is being interpreted as "do not change" (but -1 can also be used).
		549
		550	Examples:
		551
		552	# same as "chown root path" in the shell:
		553	aio_chown "path", 0, -1;
		554	# same as above:
		555	aio_chown "path", 0, undef;
		556
		557
		558	=item aio_truncate $fh_or_path, $offset, $callback->($status)
		559
		560	Works like truncate(2) or ftruncate(2).
		561
		562
		563	=item aio_chmod $fh_or_path, $mode, $callback->($status)
		564
		565	Works like perl's C<chmod> function.
		566
		567
399	=item aio_unlink $pathname, $callback->($status)	568	=item aio_unlink $pathname, $callback->($status)
400		569
401	Asynchronously unlink (delete) a file and call the callback with the	570	Asynchronously unlink (delete) a file and call the callback with the
402	result code.	571	result code.
403		572
		573
404	=item aio_mknod $path, $mode, $dev, $callback->($status)	574	=item aio_mknod $path, $mode, $dev, $callback->($status)
405		575
406	[EXPERIMENTAL]	576	[EXPERIMENTAL]
407		577
408	Asynchronously create a device node (or fifo). See mknod(2).	578	Asynchronously create a device node (or fifo). See mknod(2).
409		579
410	The only (POSIX-) portable way of calling this function is:	580	The only (POSIX-) portable way of calling this function is:
411		581
412	aio_mknod $path, IO::AIO::S_IFIFO | $mode, 0, sub { ...	582	aio_mknod $path, IO::AIO::S_IFIFO | $mode, 0, sub { ...
		583
413		584
414	=item aio_link $srcpath, $dstpath, $callback->($status)	585	=item aio_link $srcpath, $dstpath, $callback->($status)
415		586
416	Asynchronously create a new link to the existing object at C<$srcpath> at	587	Asynchronously create a new link to the existing object at C<$srcpath> at
417	the path C<$dstpath> and call the callback with the result code.	588	the path C<$dstpath> and call the callback with the result code.
418		589
		590
419	=item aio_symlink $srcpath, $dstpath, $callback->($status)	591	=item aio_symlink $srcpath, $dstpath, $callback->($status)
420		592
421	Asynchronously create a new symbolic link to the existing object at C<$srcpath> at	593	Asynchronously create a new symbolic link to the existing object at C<$srcpath> at
422	the path C<$dstpath> and call the callback with the result code.	594	the path C<$dstpath> and call the callback with the result code.
		595
423		596
424	=item aio_readlink $path, $callback->($link)	597	=item aio_readlink $path, $callback->($link)
425		598
426	Asynchronously read the symlink specified by C<$path> and pass it to	599	Asynchronously read the symlink specified by C<$path> and pass it to
427	the callback. If an error occurs, nothing or undef gets passed to the	600	the callback. If an error occurs, nothing or undef gets passed to the
428	callback.	601	callback.
429		602
		603
430	=item aio_rename $srcpath, $dstpath, $callback->($status)	604	=item aio_rename $srcpath, $dstpath, $callback->($status)
431		605
432	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as	606	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as
433	rename(2) and call the callback with the result code.	607	rename(2) and call the callback with the result code.
434		608
		609
		610	=item aio_mkdir $pathname, $mode, $callback->($status)
		611
		612	Asynchronously mkdir (create) a directory and call the callback with
		613	the result code. C<$mode> will be modified by the umask at the time the
		614	request is executed, so do not change your umask.
		615
		616
435	=item aio_rmdir $pathname, $callback->($status)	617	=item aio_rmdir $pathname, $callback->($status)
436		618
437	Asynchronously rmdir (delete) a directory and call the callback with the	619	Asynchronously rmdir (delete) a directory and call the callback with the
438	result code.	620	result code.
		621
439		622
440	=item aio_readdir $pathname, $callback->($entries)	623	=item aio_readdir $pathname, $callback->($entries)
441		624
442	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire	625	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire
443	directory (i.e. opendir + readdir + closedir). The entries will not be	626	directory (i.e. opendir + readdir + closedir). The entries will not be
444	sorted, and will B<NOT> include the C<.> and C<..> entries.	627	sorted, and will B<NOT> include the C<.> and C<..> entries.
445		628
446	The callback a single argument which is either C<undef> or an array-ref	629	The callback is passed a single argument which is either C<undef> or an
447	with the filenames.	630	array-ref with the filenames.
		631
		632
		633	=item aio_readdirx $pathname, $flags, $callback->($entries, $flags)
		634
		635	Quite similar to C<aio_readdir>, but the C<$flags> argument allows to tune
		636	behaviour and output format. In case of an error, C<$entries> will be
		637	C<undef>.
		638
		639	The flags are a combination of the following constants, ORed together (the
		640	flags will also be passed to the callback, possibly modified):
		641
		642	=over 4
		643
		644	=item IO::AIO::READDIR_DENTS
		645
		646	When this flag is off, then the callback gets an arrayref with of names
		647	only (as with C<aio_readdir>), otherwise it gets an arrayref with
		648	C<[$name, $type, $inode]> arrayrefs, each describing a single directory
		649	entry in more detail.
		650
		651	C<$name> is the name of the entry.
		652
		653	C<$type> is one of the C<IO::AIO::DT_xxx> constants:
		654
		655	C<IO::AIO::DT_UNKNOWN>, C<IO::AIO::DT_FIFO>, C<IO::AIO::DT_CHR>, C<IO::AIO::DT_DIR>,
		656	C<IO::AIO::DT_BLK>, C<IO::AIO::DT_REG>, C<IO::AIO::DT_LNK>, C<IO::AIO::DT_SOCK>,
		657	C<IO::AIO::DT_WHT>.
		658
		659	C<IO::AIO::DT_UNKNOWN> means just that: readdir does not know. If you need to
		660	know, you have to run stat yourself. Also, for speed reasons, the C<$type>
		661	scalars are read-only: you can not modify them.
		662
		663	C<$inode> is the inode number (which might not be exact on systems with 64
		664	bit inode numbers and 32 bit perls). This field has unspecified content on
		665	systems that do not deliver the inode information.
		666
		667	=item IO::AIO::READDIR_DIRS_FIRST
		668
		669	When this flag is set, then the names will be returned in an order where
		670	likely directories come first. This is useful when you need to quickly
		671	find directories, or you want to find all directories while avoiding to
		672	stat() each entry.
		673
		674	If the system returns type information in readdir, then this is used
		675	to find directories directly. Otherwise, likely directories are files
		676	beginning with ".", or otherwise files with no dots, of which files with
		677	short names are tried first.
		678
		679	=item IO::AIO::READDIR_STAT_ORDER
		680
		681	When this flag is set, then the names will be returned in an order
		682	suitable for stat()'ing each one. That is, when you plan to stat()
		683	all files in the given directory, then the returned order will likely
		684	be fastest.
		685
		686	If both this flag and C<IO::AIO::READDIR_DIRS_FIRST> are specified, then
		687	the likely dirs come first, resulting in a less optimal stat order.
		688
		689	=item IO::AIO::READDIR_FOUND_UNKNOWN
		690
		691	This flag should not be set when calling C<aio_readdirx>. Instead, it
		692	is being set by C<aio_readdirx>, when any of the C<$type>'s found were
		693	C<IO::AIO::DT_UNKNOWN>. The absense of this flag therefore indicates that all
		694	C<$type>'s are known, which can be used to speed up some algorithms.
		695
		696	=back
		697
		698
		699	=item aio_load $path, $data, $callback->($status)
		700
		701	This is a composite request that tries to fully load the given file into
		702	memory. Status is the same as with aio_read.
		703
		704	=cut
		705
		706	sub aio_load($$;$) {
		707	my ($path, undef, $cb) = @_;
		708	my $data = \$_[1];
		709
		710	my $pri = aioreq_pri;
		711	my $grp = aio_group $cb;
		712
		713	aioreq_pri $pri;
		714	add $grp aio_open $path, O_RDONLY, 0, sub {
		715	my $fh = shift
		716	or return $grp->result (-1);
		717
		718	aioreq_pri $pri;
		719	add $grp aio_read $fh, 0, (-s $fh), $$data, 0, sub {
		720	$grp->result ($_[0]);
		721	};
		722	};
		723
		724	$grp
		725	}
448		726
449	=item aio_copy $srcpath, $dstpath, $callback->($status)	727	=item aio_copy $srcpath, $dstpath, $callback->($status)
450		728
451	Try to copy the I<file> (directories not supported as either source or	729	Try to copy the I<file> (directories not supported as either source or
452	destination) from C<$srcpath> to C<$dstpath> and call the callback with	730	destination) from C<$srcpath> to C<$dstpath> and call the callback with
453	the C<0> (error) or C<-1> ok.	731	a status of C<0> (ok) or C<-1> (error, see C<$!>).
454		732
455	This is a composite request that it creates the destination file with	733	This is a composite request that creates the destination file with
456	mode 0200 and copies the contents of the source file into it using	734	mode 0200 and copies the contents of the source file into it using
457	C<aio_sendfile>, followed by restoring atime, mtime, access mode and	735	C<aio_sendfile>, followed by restoring atime, mtime, access mode and
458	uid/gid, in that order.	736	uid/gid, in that order.
459		737
460	If an error occurs, the partial destination file will be unlinked, if	738	If an error occurs, the partial destination file will be unlinked, if
…		…
462	errors are being ignored.	740	errors are being ignored.
463		741
464	=cut	742	=cut
465		743
466	sub aio_copy($$;$) {	744	sub aio_copy($$;$) {
467	aio_block {
468	my ($src, $dst, $cb) = @_;	745	my ($src, $dst, $cb) = @_;
469		746
470	my $pri = aioreq_pri;	747	my $pri = aioreq_pri;
471	my $grp = aio_group $cb;	748	my $grp = aio_group $cb;
472		749
473	aioreq_pri $pri;	750	aioreq_pri $pri;
474	add $grp aio_open $src, O_RDONLY, 0, sub {	751	add $grp aio_open $src, O_RDONLY, 0, sub {
475	if (my $src_fh = $_[0]) {	752	if (my $src_fh = $_[0]) {
476	my @stat = stat $src_fh;	753	my @stat = stat $src_fh; # hmm, might block over nfs?
477		754
478	aioreq_pri $pri;	755	aioreq_pri $pri;
479	add $grp aio_open $dst, O_CREAT | O_WRONLY | O_TRUNC, 0200, sub {	756	add $grp aio_open $dst, O_CREAT | O_WRONLY | O_TRUNC, 0200, sub {
480	if (my $dst_fh = $_[0]) {	757	if (my $dst_fh = $_[0]) {
481	aioreq_pri $pri;	758	aioreq_pri $pri;
482	add $grp aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub {	759	add $grp aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub {
483	if ($_[0] == $stat[7]) {	760	if ($_[0] == $stat[7]) {
484	$grp->result (0);	761	$grp->result (0);
485	close $src_fh;	762	close $src_fh;
486		763
487	# those should not normally block. should. should.
488	utime $stat[8], $stat[9], $dst;
489	chmod $stat[2] & 07777, $dst_fh;
490	chown $stat[4], $stat[5], $dst_fh;
491	close $dst_fh;
492	} else {	764	my $ch = sub {
493	$grp->result (-1);
494	close $src_fh;
495	close $dst_fh;
496
497	aioreq $pri;	765	aioreq_pri $pri;
		766	add $grp aio_chmod $dst_fh, $stat[2] & 07777, sub {
		767	aioreq_pri $pri;
		768	add $grp aio_chown $dst_fh, $stat[4], $stat[5], sub {
		769	aioreq_pri $pri;
498	add $grp aio_unlink $dst;	770	add $grp aio_close $dst_fh;
		771	}
		772	};
499	}	773	};
		774
		775	aioreq_pri $pri;
		776	add $grp aio_utime $dst_fh, $stat[8], $stat[9], sub {
		777	if ($_[0] < 0 && $! == ENOSYS) {
		778	aioreq_pri $pri;
		779	add $grp aio_utime $dst, $stat[8], $stat[9], $ch;
		780	} else {
		781	$ch->();
		782	}
		783	};
		784	} else {
		785	$grp->result (-1);
		786	close $src_fh;
		787	close $dst_fh;
		788
		789	aioreq $pri;
		790	add $grp aio_unlink $dst;
500	};	791	}
501	} else {
502	$grp->result (-1);
503	}	792	};
		793	} else {
		794	$grp->result (-1);
504	},	795	}
505
506	} else {
507	$grp->result (-1);
508	}	796	},
		797
		798	} else {
		799	$grp->result (-1);
509	};	800	}
510
511	$grp
512	}	801	};
		802
		803	$grp
513	}	804	}
514		805
515	=item aio_move $srcpath, $dstpath, $callback->($status)	806	=item aio_move $srcpath, $dstpath, $callback->($status)
516		807
517	Try to move the I<file> (directories not supported as either source or	808	Try to move the I<file> (directories not supported as either source or
518	destination) from C<$srcpath> to C<$dstpath> and call the callback with	809	destination) from C<$srcpath> to C<$dstpath> and call the callback with
519	the C<0> (error) or C<-1> ok.	810	a status of C<0> (ok) or C<-1> (error, see C<$!>).
520		811
521	This is a composite request that tries to rename(2) the file first. If	812	This is a composite request that tries to rename(2) the file first; if
522	rename files with C<EXDEV>, it copies the file with C<aio_copy> and, if	813	rename fails with C<EXDEV>, it copies the file with C<aio_copy> and, if
523	that is successful, unlinking the C<$srcpath>.	814	that is successful, unlinks the C<$srcpath>.
524		815
525	=cut	816	=cut
526		817
527	sub aio_move($$;$) {	818	sub aio_move($$;$) {
528	aio_block {
529	my ($src, $dst, $cb) = @_;	819	my ($src, $dst, $cb) = @_;
530		820
531	my $pri = aioreq_pri;	821	my $pri = aioreq_pri;
532	my $grp = aio_group $cb;	822	my $grp = aio_group $cb;
533		823
534	aioreq_pri $pri;	824	aioreq_pri $pri;
535	add $grp aio_rename $src, $dst, sub {	825	add $grp aio_rename $src, $dst, sub {
536	if ($_[0] && $! == EXDEV) {	826	if ($_[0] && $! == EXDEV) {
537	aioreq_pri $pri;	827	aioreq_pri $pri;
538	add $grp aio_copy $src, $dst, sub {	828	add $grp aio_copy $src, $dst, sub {
539	$grp->result ($_[0]);
540
541	if (!$_[0]) {
542	aioreq_pri $pri;
543	add $grp aio_unlink $src;
544	}
545	};
546	} else {
547	$grp->result ($_[0]);	829	$grp->result ($_[0]);
		830
		831	if (!$_[0]) {
		832	aioreq_pri $pri;
		833	add $grp aio_unlink $src;
		834	}
548	}	835	};
		836	} else {
		837	$grp->result ($_[0]);
549	};	838	}
550
551	$grp
552	}	839	};
		840
		841	$grp
553	}	842	}
554		843
555	=item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)	844	=item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
556		845
557	Scans a directory (similar to C<aio_readdir>) but additionally tries to	846	Scans a directory (similar to C<aio_readdir>) but additionally tries to
…		…
577		866
578	Implementation notes.	867	Implementation notes.
579		868
580	The C<aio_readdir> cannot be avoided, but C<stat()>'ing every entry can.	869	The C<aio_readdir> cannot be avoided, but C<stat()>'ing every entry can.
581		870
		871	If readdir returns file type information, then this is used directly to
		872	find directories.
		873
582	After reading the directory, the modification time, size etc. of the	874	Otherwise, after reading the directory, the modification time, size etc.
583	directory before and after the readdir is checked, and if they match (and	875	of the directory before and after the readdir is checked, and if they
584	isn't the current time), the link count will be used to decide how many	876	match (and isn't the current time), the link count will be used to decide
585	entries are directories (if >= 2). Otherwise, no knowledge of the number	877	how many entries are directories (if >= 2). Otherwise, no knowledge of the
586	of subdirectories will be assumed.	878	number of subdirectories will be assumed.
587		879
588	Then entries will be sorted into likely directories (everything without	880	Then entries will be sorted into likely directories a non-initial dot
589	a non-initial dot currently) and likely non-directories (everything	881	currently) and likely non-directories (see C<aio_readdirx>). Then every
590	else). Then every entry plus an appended C</.> will be C<stat>'ed,	882	entry plus an appended C</.> will be C<stat>'ed, likely directories first,
591	likely directories first. If that succeeds, it assumes that the entry	883	in order of their inode numbers. If that succeeds, it assumes that the
592	is a directory or a symlink to directory (which will be checked	884	entry is a directory or a symlink to directory (which will be checked
593	seperately). This is often faster than stat'ing the entry itself because	885	seperately). This is often faster than stat'ing the entry itself because
594	filesystems might detect the type of the entry without reading the inode	886	filesystems might detect the type of the entry without reading the inode
595	data (e.g. ext2fs filetype feature).	887	data (e.g. ext2fs filetype feature), even on systems that cannot return
		888	the filetype information on readdir.
596		889
597	If the known number of directories (link count - 2) has been reached, the	890	If the known number of directories (link count - 2) has been reached, the
598	rest of the entries is assumed to be non-directories.	891	rest of the entries is assumed to be non-directories.
599		892
600	This only works with certainty on POSIX (= UNIX) filesystems, which	893	This only works with certainty on POSIX (= UNIX) filesystems, which
…		…
604	as those tend to return 0 or 1 as link counts, which disables the	897	as those tend to return 0 or 1 as link counts, which disables the
605	directory counting heuristic.	898	directory counting heuristic.
606		899
607	=cut	900	=cut
608		901
609	sub aio_scandir($$$) {	902	sub aio_scandir($$;$) {
610	aio_block {
611	my ($path, $maxreq, $cb) = @_;	903	my ($path, $maxreq, $cb) = @_;
612		904
613	my $pri = aioreq_pri;	905	my $pri = aioreq_pri;
614		906
615	my $grp = aio_group $cb;	907	my $grp = aio_group $cb;
616		908
617	$maxreq = 4 if $maxreq <= 0;	909	$maxreq = 4 if $maxreq <= 0;
618		910
619	# stat once	911	# stat once
		912	aioreq_pri $pri;
		913	add $grp aio_stat $path, sub {
		914	return $grp->result () if $_[0];
		915	my $now = time;
		916	my $hash1 = join ":", (stat _)[0,1,3,7,9];
		917
		918	# read the directory entries
620	aioreq_pri $pri;	919	aioreq_pri $pri;
621	add $grp aio_stat $path, sub {	920	add $grp aio_readdirx $path, READDIR_DIRS_FIRST, sub {
		921	my $entries = shift
622	return $grp->result () if $_[0];	922	or return $grp->result ();
623	my $now = time;
624	my $hash1 = join ":", (stat _)[0,1,3,7,9];
625		923
626	# read the directory entries	924	# stat the dir another time
627	aioreq_pri $pri;	925	aioreq_pri $pri;
628	add $grp aio_readdir $path, sub {
629	my $entries = shift
630	or return $grp->result ();
631
632	# stat the dir another time
633	aioreq_pri $pri;
634	add $grp aio_stat $path, sub {	926	add $grp aio_stat $path, sub {
635	my $hash2 = join ":", (stat _)[0,1,3,7,9];	927	my $hash2 = join ":", (stat _)[0,1,3,7,9];
636		928
637	my $ndirs;	929	my $ndirs;
638		930
639	# take the slow route if anything looks fishy	931	# take the slow route if anything looks fishy
640	if ($hash1 ne $hash2 or (stat _)[9] == $now) {	932	if ($hash1 ne $hash2 or (stat _)[9] == $now) {
641	$ndirs = -1;	933	$ndirs = -1;
642	} else {	934	} else {
643	# if nlink == 2, we are finished	935	# if nlink == 2, we are finished
644	# on non-posix-fs's, we rely on nlink < 2	936	# for non-posix-fs's, we rely on nlink < 2
645	$ndirs = (stat _)[3] - 2	937	$ndirs = (stat _)[3] - 2
646	or return $grp->result ([], $entries);	938	or return $grp->result ([], $entries);
647	}	939	}
648		940
649	# sort into likely dirs and likely nondirs
650	# dirs == files without ".", short entries first
651	$entries = [map $_->[0],
652	sort { $b->[1] cmp $a->[1] }
653	map [$_, sprintf "%s%04d", (/.\./ ? "1" : "0"), length],
654	@$entries];
655
656	my (@dirs, @nondirs);	941	my (@dirs, @nondirs);
657		942
658	my $statgrp = add $grp aio_group sub {	943	my $statgrp = add $grp aio_group sub {
659	$grp->result (\@dirs, \@nondirs);	944	$grp->result (\@dirs, \@nondirs);
660	};	945	};
661		946
662	limit $statgrp $maxreq;	947	limit $statgrp $maxreq;
663	feed $statgrp sub {	948	feed $statgrp sub {
664	return unless @$entries;	949	return unless @$entries;
665	my $entry = pop @$entries;	950	my $entry = shift @$entries;
666		951
667	aioreq_pri $pri;	952	aioreq_pri $pri;
668	add $statgrp aio_stat "$path/$entry/.", sub {	953	add $statgrp aio_stat "$path/$entry/.", sub {
669	if ($_[0] < 0) {	954	if ($_[0] < 0) {
670	push @nondirs, $entry;	955	push @nondirs, $entry;
671	} else {	956	} else {
672	# need to check for real directory	957	# need to check for real directory
673	aioreq_pri $pri;	958	aioreq_pri $pri;
674	add $statgrp aio_lstat "$path/$entry", sub {	959	add $statgrp aio_lstat "$path/$entry", sub {
675	if (-d _) {	960	if (-d _) {
676	push @dirs, $entry;	961	push @dirs, $entry;
677		962
678	unless (--$ndirs) {	963	unless (--$ndirs) {
679	push @nondirs, @$entries;	964	push @nondirs, @$entries;
680	feed $statgrp;	965	feed $statgrp;
681	}
682	} else {
683	push @nondirs, $entry;
684	}	966	}
		967	} else {
		968	push @nondirs, $entry;
685	}	969	}
686	}	970	}
687	};	971	}
688	};	972	};
689	};	973	};
690	};	974	};
691	};	975	};
692
693	$grp
694	}	976	};
		977
		978	$grp
695	}	979	}
		980
		981	=item aio_rmtree $path, $callback->($status)
		982
		983	Delete a directory tree starting (and including) C<$path>, return the
		984	status of the final C<rmdir> only. This is a composite request that
		985	uses C<aio_scandir> to recurse into and rmdir directories, and unlink
		986	everything else.
		987
		988	=cut
		989
		990	sub aio_rmtree;
		991	sub aio_rmtree($;$) {
		992	my ($path, $cb) = @_;
		993
		994	my $pri = aioreq_pri;
		995	my $grp = aio_group $cb;
		996
		997	aioreq_pri $pri;
		998	add $grp aio_scandir $path, 0, sub {
		999	my ($dirs, $nondirs) = @_;
		1000
		1001	my $dirgrp = aio_group sub {
		1002	add $grp aio_rmdir $path, sub {
		1003	$grp->result ($_[0]);
		1004	};
		1005	};
		1006
		1007	(aioreq_pri $pri), add $dirgrp aio_rmtree "$path/$_" for @$dirs;
		1008	(aioreq_pri $pri), add $dirgrp aio_unlink "$path/$_" for @$nondirs;
		1009
		1010	add $grp $dirgrp;
		1011	};
		1012
		1013	$grp
		1014	}
		1015
		1016	=item aio_sync $callback->($status)
		1017
		1018	Asynchronously call sync and call the callback when finished.
696		1019
697	=item aio_fsync $fh, $callback->($status)	1020	=item aio_fsync $fh, $callback->($status)
698		1021
699	Asynchronously call fsync on the given filehandle and call the callback	1022	Asynchronously call fsync on the given filehandle and call the callback
700	with the fsync result code.	1023	with the fsync result code.
…		…
704	Asynchronously call fdatasync on the given filehandle and call the	1027	Asynchronously call fdatasync on the given filehandle and call the
705	callback with the fdatasync result code.	1028	callback with the fdatasync result code.
706		1029
707	If this call isn't available because your OS lacks it or it couldn't be	1030	If this call isn't available because your OS lacks it or it couldn't be
708	detected, it will be emulated by calling C<fsync> instead.	1031	detected, it will be emulated by calling C<fsync> instead.
		1032
		1033	=item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
		1034
		1035	Sync the data portion of the file specified by C<$offset> and C<$length>
		1036	to disk (but NOT the metadata), by calling the Linux-specific
		1037	sync_file_range call. If sync_file_range is not available or it returns
		1038	ENOSYS, then fdatasync or fsync is being substituted.
		1039
		1040	C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>,
		1041	C<IO::AIO::SYNC_FILE_RANGE_WRITE> and
		1042	C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range
		1043	manpage for details.
		1044
		1045	=item aio_pathsync $path, $callback->($status)
		1046
		1047	This request tries to open, fsync and close the given path. This is a
		1048	composite request intended to sync directories after directory operations
		1049	(E.g. rename). This might not work on all operating systems or have any
		1050	specific effect, but usually it makes sure that directory changes get
		1051	written to disc. It works for anything that can be opened for read-only,
		1052	not just directories.
		1053
		1054	Future versions of this function might fall back to other methods when
		1055	C<fsync> on the directory fails (such as calling C<sync>).
		1056
		1057	Passes C<0> when everything went ok, and C<-1> on error.
		1058
		1059	=cut
		1060
		1061	sub aio_pathsync($;$) {
		1062	my ($path, $cb) = @_;
		1063
		1064	my $pri = aioreq_pri;
		1065	my $grp = aio_group $cb;
		1066
		1067	aioreq_pri $pri;
		1068	add $grp aio_open $path, O_RDONLY, 0, sub {
		1069	my ($fh) = @_;
		1070	if ($fh) {
		1071	aioreq_pri $pri;
		1072	add $grp aio_fsync $fh, sub {
		1073	$grp->result ($_[0]);
		1074
		1075	aioreq_pri $pri;
		1076	add $grp aio_close $fh;
		1077	};
		1078	} else {
		1079	$grp->result (-1);
		1080	}
		1081	};
		1082
		1083	$grp
		1084	}
		1085
		1086	=item aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
		1087
		1088	This is a rather advanced IO::AIO call, which only works on mmap(2)ed
		1089	scalars (see the C<IO::AIO::mmap> function, although it also works on data
		1090	scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the
		1091	scalar must only be modified in-place while an aio operation is pending on
		1092	it).
		1093
		1094	It calls the C<msync> function of your OS, if available, with the memory
		1095	area starting at C<$offset> in the string and ending C<$length> bytes
		1096	later. If C<$length> is negative, counts from the end, and if C<$length>
		1097	is C<undef>, then it goes till the end of the string. The flags can be
		1098	a combination of C<IO::AIO::MS_ASYNC>, C<IO::AIO::MS_INVALIDATE> and
		1099	C<IO::AIO::MS_SYNC>.
		1100
		1101	=item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
		1102
		1103	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
		1104	scalars.
		1105
		1106	It touches (reads or writes) all memory pages in the specified
		1107	range inside the scalar. All caveats and parameters are the same
		1108	as for C<aio_msync>, above, except for flags, which must be either
		1109	C<0> (which reads all pages and ensures they are instantiated) or
		1110	C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and
		1111	writing an octet from it, which dirties the page).
709		1112
710	=item aio_group $callback->(...)	1113	=item aio_group $callback->(...)
711		1114
712	This is a very special aio request: Instead of doing something, it is a	1115	This is a very special aio request: Instead of doing something, it is a
713	container for other aio requests, which is useful if you want to bundle	1116	container for other aio requests, which is useful if you want to bundle
…		…
763	=item cancel $req	1166	=item cancel $req
764		1167
765	Cancels the request, if possible. Has the effect of skipping execution	1168	Cancels the request, if possible. Has the effect of skipping execution
766	when entering the B<execute> state and skipping calling the callback when	1169	when entering the B<execute> state and skipping calling the callback when
767	entering the the B<result> state, but will leave the request otherwise	1170	entering the the B<result> state, but will leave the request otherwise
768	untouched. That means that requests that currently execute will not be	1171	untouched (with the exception of readdir). That means that requests that
769	stopped and resources held by the request will not be freed prematurely.	1172	currently execute will not be stopped and resources held by the request
		1173	will not be freed prematurely.
770		1174
771	=item cb $req $callback->(...)	1175	=item cb $req $callback->(...)
772		1176
773	Replace (or simply set) the callback registered to the request.	1177	Replace (or simply set) the callback registered to the request.
774		1178
…		…
825	Their lifetime, simplified, looks like this: when they are empty, they	1229	Their lifetime, simplified, looks like this: when they are empty, they
826	will finish very quickly. If they contain only requests that are in the	1230	will finish very quickly. If they contain only requests that are in the
827	C<done> state, they will also finish. Otherwise they will continue to	1231	C<done> state, they will also finish. Otherwise they will continue to
828	exist.	1232	exist.
829		1233
830	That means after creating a group you have some time to add requests. And	1234	That means after creating a group you have some time to add requests
831	in the callbacks of those requests, you can add further requests to the	1235	(precisely before the callback has been invoked, which is only done within
832	group. And only when all those requests have finished will the the group	1236	the C<poll_cb>). And in the callbacks of those requests, you can add
833	itself finish.	1237	further requests to the group. And only when all those requests have
		1238	finished will the the group itself finish.
834		1239
835	=over 4	1240	=over 4
836		1241
837	=item add $grp ...	1242	=item add $grp ...
838		1243
…		…
847	=item $grp->cancel_subs	1252	=item $grp->cancel_subs
848		1253
849	Cancel all subrequests and clears any feeder, but not the group request	1254	Cancel all subrequests and clears any feeder, but not the group request
850	itself. Useful when you queued a lot of events but got a result early.	1255	itself. Useful when you queued a lot of events but got a result early.
851		1256
		1257	The group request will finish normally (you cannot add requests to the
		1258	group).
		1259
852	=item $grp->result (...)	1260	=item $grp->result (...)
853		1261
854	Set the result value(s) that will be passed to the group callback when all	1262	Set the result value(s) that will be passed to the group callback when all
855	subrequests have finished and set thre groups errno to the current value	1263	subrequests have finished and set the groups errno to the current value
856	of errno (just like calling C<errno> without an error number). By default,	1264	of errno (just like calling C<errno> without an error number). By default,
857	no argument will be passed and errno is zero.	1265	no argument will be passed and errno is zero.
858		1266
859	=item $grp->errno ([$errno])	1267	=item $grp->errno ([$errno])
860		1268
…		…
871	=item feed $grp $callback->($grp)	1279	=item feed $grp $callback->($grp)
872		1280
873	Sets a feeder/generator on this group: every group can have an attached	1281	Sets a feeder/generator on this group: every group can have an attached
874	generator that generates requests if idle. The idea behind this is that,	1282	generator that generates requests if idle. The idea behind this is that,
875	although you could just queue as many requests as you want in a group,	1283	although you could just queue as many requests as you want in a group,
876	this might starve other requests for a potentially long time. For	1284	this might starve other requests for a potentially long time. For example,
877	example, C<aio_scandir> might generate hundreds of thousands C<aio_stat>	1285	C<aio_scandir> might generate hundreds of thousands C<aio_stat> requests,
878	requests, delaying any later requests for a long time.	1286	delaying any later requests for a long time.
879		1287
880	To avoid this, and allow incremental generation of requests, you can	1288	To avoid this, and allow incremental generation of requests, you can
881	instead a group and set a feeder on it that generates those requests. The	1289	instead a group and set a feeder on it that generates those requests. The
882	feed callback will be called whenever there are few enough (see C<limit>,	1290	feed callback will be called whenever there are few enough (see C<limit>,
883	below) requests active in the group itself and is expected to queue more	1291	below) requests active in the group itself and is expected to queue more
…		…
887	not impose any limits).	1295	not impose any limits).
888		1296
889	If the feed does not queue more requests when called, it will be	1297	If the feed does not queue more requests when called, it will be
890	automatically removed from the group.	1298	automatically removed from the group.
891		1299
892	If the feed limit is C<0>, it will be set to C<2> automatically.	1300	If the feed limit is C<0> when this method is called, it will be set to
		1301	C<2> automatically.
893		1302
894	Example:	1303	Example:
895		1304
896	# stat all files in @files, but only ever use four aio requests concurrently:	1305	# stat all files in @files, but only ever use four aio requests concurrently:
897		1306
…		…
909	Sets the feeder limit for the group: The feeder will be called whenever	1318	Sets the feeder limit for the group: The feeder will be called whenever
910	the group contains less than this many requests.	1319	the group contains less than this many requests.
911		1320
912	Setting the limit to C<0> will pause the feeding process.	1321	Setting the limit to C<0> will pause the feeding process.
913		1322
		1323	The default value for the limit is C<0>, but note that setting a feeder
		1324	automatically bumps it up to C<2>.
		1325
914	=back	1326	=back
915		1327
916	=head2 SUPPORT FUNCTIONS	1328	=head2 SUPPORT FUNCTIONS
917		1329
918	=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION	1330	=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION
…		…
920	=over 4	1332	=over 4
921		1333
922	=item $fileno = IO::AIO::poll_fileno	1334	=item $fileno = IO::AIO::poll_fileno
923		1335
924	Return the I<request result pipe file descriptor>. This filehandle must be	1336	Return the I<request result pipe file descriptor>. This filehandle must be
925	polled for reading by some mechanism outside this module (e.g. Event or	1337	polled for reading by some mechanism outside this module (e.g. EV, Glib,
926	select, see below or the SYNOPSIS). If the pipe becomes readable you have	1338	select and so on, see below or the SYNOPSIS). If the pipe becomes readable
927	to call C<poll_cb> to check the results.	1339	you have to call C<poll_cb> to check the results.
928		1340
929	See C<poll_cb> for an example.	1341	See C<poll_cb> for an example.
930		1342
931	=item IO::AIO::poll_cb	1343	=item IO::AIO::poll_cb
932		1344
933	Process some outstanding events on the result pipe. You have to call this	1345	Process some outstanding events on the result pipe. You have to call this
934	regularly. Returns the number of events processed. Returns immediately	1346	regularly. Returns C<0> if all events could be processed, or C<-1> if it
		1347	returned earlier for whatever reason. Returns immediately when no events
935	when no events are outstanding. The amount of events processed depends on	1348	are outstanding. The amount of events processed depends on the settings of
936	the settings of C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>.	1349	C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>.
937		1350
938	If not all requests were processed for whatever reason, the filehandle	1351	If not all requests were processed for whatever reason, the filehandle
939	will still be ready when C<poll_cb> returns.	1352	will still be ready when C<poll_cb> returns, so normally you don't have to
		1353	do anything special to have it called later.
940		1354
941	Example: Install an Event watcher that automatically calls	1355	Example: Install an Event watcher that automatically calls
942	IO::AIO::poll_cb with high priority:	1356	IO::AIO::poll_cb with high priority (more examples can be found in the
		1357	SYNOPSIS section, at the top of this document):
943		1358
944	Event->io (fd => IO::AIO::poll_fileno,	1359	Event->io (fd => IO::AIO::poll_fileno,
945	poll => 'r', async => 1,	1360	poll => 'r', async => 1,
946	cb => \&IO::AIO::poll_cb);	1361	cb => \&IO::AIO::poll_cb);
		1362
		1363	=item IO::AIO::poll_wait
		1364
		1365	If there are any outstanding requests and none of them in the result
		1366	phase, wait till the result filehandle becomes ready for reading (simply
		1367	does a C<select> on the filehandle. This is useful if you want to
		1368	synchronously wait for some requests to finish).
		1369
		1370	See C<nreqs> for an example.
		1371
		1372	=item IO::AIO::poll
		1373
		1374	Waits until some requests have been handled.
		1375
		1376	Returns the number of requests processed, but is otherwise strictly
		1377	equivalent to:
		1378
		1379	IO::AIO::poll_wait, IO::AIO::poll_cb
		1380
		1381	=item IO::AIO::flush
		1382
		1383	Wait till all outstanding AIO requests have been handled.
		1384
		1385	Strictly equivalent to:
		1386
		1387	IO::AIO::poll_wait, IO::AIO::poll_cb
		1388	while IO::AIO::nreqs;
947		1389
948	=item IO::AIO::max_poll_reqs $nreqs	1390	=item IO::AIO::max_poll_reqs $nreqs
949		1391
950	=item IO::AIO::max_poll_time $seconds	1392	=item IO::AIO::max_poll_time $seconds
951		1393
…		…
976	# use a low priority so other tasks have priority	1418	# use a low priority so other tasks have priority
977	Event->io (fd => IO::AIO::poll_fileno,	1419	Event->io (fd => IO::AIO::poll_fileno,
978	poll => 'r', nice => 1,	1420	poll => 'r', nice => 1,
979	cb => &IO::AIO::poll_cb);	1421	cb => &IO::AIO::poll_cb);
980		1422
981	=item IO::AIO::poll_wait	1423	=back
982
983	If there are any outstanding requests and none of them in the result
984	phase, wait till the result filehandle becomes ready for reading (simply
985	does a C<select> on the filehandle. This is useful if you want to
986	synchronously wait for some requests to finish).
987
988	See C<nreqs> for an example.
989
990	=item IO::AIO::poll
991
992	Waits until some requests have been handled.
993
994	Returns the number of requests processed, but is otherwise strictly
995	equivalent to:
996
997	IO::AIO::poll_wait, IO::AIO::poll_cb
998
999	=item IO::AIO::flush
1000
1001	Wait till all outstanding AIO requests have been handled.
1002
1003	Strictly equivalent to:
1004
1005	IO::AIO::poll_wait, IO::AIO::poll_cb
1006	while IO::AIO::nreqs;
1007		1424
1008	=head3 CONTROLLING THE NUMBER OF THREADS	1425	=head3 CONTROLLING THE NUMBER OF THREADS
		1426
		1427	=over
1009		1428
1010	=item IO::AIO::min_parallel $nthreads	1429	=item IO::AIO::min_parallel $nthreads
1011		1430
1012	Set the minimum number of AIO threads to C<$nthreads>. The current	1431	Set the minimum number of AIO threads to C<$nthreads>. The current
1013	default is C<8>, which means eight asynchronous operations can execute	1432	default is C<8>, which means eight asynchronous operations can execute
…		…
1054		1473
1055	The default is probably ok in most situations, especially if thread	1474	The default is probably ok in most situations, especially if thread
1056	creation is fast. If thread creation is very slow on your system you might	1475	creation is fast. If thread creation is very slow on your system you might
1057	want to use larger values.	1476	want to use larger values.
1058		1477
1059	=item $oldmaxreqs = IO::AIO::max_outstanding $maxreqs	1478	=item IO::AIO::max_outstanding $maxreqs
1060		1479
1061	This is a very bad function to use in interactive programs because it	1480	This is a very bad function to use in interactive programs because it
1062	blocks, and a bad way to reduce concurrency because it is inexact: Better	1481	blocks, and a bad way to reduce concurrency because it is inexact: Better
1063	use an C<aio_group> together with a feed callback.	1482	use an C<aio_group> together with a feed callback.
1064		1483
1065	Sets the maximum number of outstanding requests to C<$nreqs>. If you	1484	Sets the maximum number of outstanding requests to C<$nreqs>. If you
1066	to queue up more than this number of requests, the next call to the	1485	do queue up more than this number of requests, the next call to the
1067	C<poll_cb> (and C<poll_some> and other functions calling C<poll_cb>)	1486	C<poll_cb> (and C<poll_some> and other functions calling C<poll_cb>)
1068	function will block until the limit is no longer exceeded.	1487	function will block until the limit is no longer exceeded.
1069		1488
1070	The default value is very large, so there is no practical limit on the	1489	The default value is very large, so there is no practical limit on the
1071	number of outstanding requests.	1490	number of outstanding requests.
1072		1491
1073	You can still queue as many requests as you want. Therefore,	1492	You can still queue as many requests as you want. Therefore,
1074	C<max_oustsanding> is mainly useful in simple scripts (with low values) or	1493	C<max_outstanding> is mainly useful in simple scripts (with low values) or
1075	as a stop gap to shield against fatal memory overflow (with large values).	1494	as a stop gap to shield against fatal memory overflow (with large values).
1076		1495
		1496	=back
		1497
1077	=head3 STATISTICAL INFORMATION	1498	=head3 STATISTICAL INFORMATION
		1499
		1500	=over
1078		1501
1079	=item IO::AIO::nreqs	1502	=item IO::AIO::nreqs
1080		1503
1081	Returns the number of requests currently in the ready, execute or pending	1504	Returns the number of requests currently in the ready, execute or pending
1082	states (i.e. for which their callback has not been invoked yet).	1505	states (i.e. for which their callback has not been invoked yet).
…		…
1096	Returns the number of requests currently in the pending state (executed,	1519	Returns the number of requests currently in the pending state (executed,
1097	but not yet processed by poll_cb).	1520	but not yet processed by poll_cb).
1098		1521
1099	=back	1522	=back
1100		1523
		1524	=head3 MISCELLANEOUS FUNCTIONS
		1525
		1526	IO::AIO implements some functions that might be useful, but are not
		1527	asynchronous.
		1528
		1529	=over 4
		1530
		1531	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
		1532
		1533	Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>,
		1534	but is blocking (this makes most sense if you know the input data is
		1535	likely cached already and the output filehandle is set to non-blocking
		1536	operations).
		1537
		1538	Returns the number of bytes copied, or C<-1> on error.
		1539
		1540	=item IO::AIO::fadvise $fh, $offset, $len, $advice
		1541
		1542	Simply calls the C<posix_fadvise> function (see it's
		1543	manpage for details). The following advice constants are
		1544	avaiable: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>,
		1545	C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>,
		1546	C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>.
		1547
		1548	On systems that do not implement C<posix_fadvise>, this function returns
		1549	ENOSYS, otherwise the return value of C<posix_fadvise>.
		1550
		1551	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]
		1552
		1553	Memory-maps a file (or anonymous memory range) and attaches it to the
		1554	given C<$scalar>, which will act like a string scalar.
		1555
		1556	The only operations allowed on the scalar are C<substr>/C<vec> that don't
		1557	change the string length, and most read-only operations such as copying it
		1558	or searching it with regexes and so on.
		1559
		1560	Anything else is unsafe and will, at best, result in memory leaks.
		1561
		1562	The memory map associated with the C<$scalar> is automatically removed
		1563	when the C<$scalar> is destroyed, or when the C<IO::AIO::mmap> or
		1564	C<IO::AIO::munmap> functions are called.
		1565
		1566	This calls the C<mmap>(2) function internally. See your system's manual
		1567	page for details on the C<$length>, C<$prot> and C<$flags> parameters.
		1568
		1569	The C<$length> must be larger than zero and smaller than the actual
		1570	filesize.
		1571
		1572	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,
		1573	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,
		1574
		1575	C<$flags> can be a combination of C<IO::AIO::MAP_SHARED> or
		1576	C<IO::AIO::MAP_PRIVATE>, or a number of system-specific flags (when
		1577	not available, the are defined as 0): C<IO::AIO::MAP_ANONYMOUS>
		1578	(which is set to C<MAP_ANON> if your system only provides this
		1579	constant), C<IO::AIO::MAP_HUGETLB>, C<IO::AIO::MAP_LOCKED>,
		1580	C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or
		1581	C<IO::AIO::MAP_NONBLOCK>
		1582
		1583	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.
		1584
		1585	C<$offset> is the offset from the start of the file - it generally must be
		1586	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.
		1587
		1588	Example:
		1589
		1590	use Digest::MD5;
		1591	use IO::AIO;
		1592
		1593	open my $fh, "<verybigfile"
		1594	or die "$!";
		1595
		1596	IO::AIO::mmap my $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh
		1597	or die "verybigfile: $!";
		1598
		1599	my $fast_md5 = md5 $data;
		1600
		1601	=item IO::AIO::munmap $scalar
		1602
		1603	Removes a previous mmap and undefines the C<$scalar>.
		1604
		1605	=item IO::AIO::mlockall $flags
		1606
		1607	Calls the C<mlockall> function with the given C<$flags> (a combination of
		1608	C<IO::AIO::MCL_CURRENT> and C<IO::AIO::MCL__FUTURE>).
		1609
		1610	On systems that do not implement C<mlockall>, this function returns
		1611	ENOSYS, otherwise the return value of C<mlockall>.
		1612
		1613	=item IO::AIO::munlockall
		1614
		1615	Calls the C<munlockall> function.
		1616
		1617	On systems that do not implement C<munlockall>, this function returns
		1618	ENOSYS, otherwise the return value of C<munlockall>.
		1619
		1620	=back
		1621
1101	=cut	1622	=cut
1102		1623
1103	# support function to convert a fd into a perl filehandle
1104	sub _fd2fh {
1105	return undef if $_[0] < 0;
1106
1107	# try to generate nice filehandles
1108	my $sym = "IO::AIO::fd#$_[0]";
1109	local *$sym;
1110
1111	open *$sym, "+<&=$_[0]" # usually works under any unix
1112	or open *$sym, "<&=$_[0]" # cygwin needs this
1113	or open *$sym, ">&=$_[0]" # or this
1114	or return undef;
1115
1116	*$sym
1117	}
1118
1119	min_parallel 8;	1624	min_parallel 8;
1120		1625
1121	END { flush }	1626	END { flush }
1122		1627
1123	1;	1628	1;
		1629
		1630	=head1 EVENT LOOP INTEGRATION
		1631
		1632	It is recommended to use L<AnyEvent::AIO> to integrate IO::AIO
		1633	automatically into many event loops:
		1634
		1635	# AnyEvent integration (EV, Event, Glib, Tk, POE, urxvt, pureperl...)
		1636	use AnyEvent::AIO;
		1637
		1638	You can also integrate IO::AIO manually into many event loops, here are
		1639	some examples of how to do this:
		1640
		1641	# EV integration
		1642	my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
		1643
		1644	# Event integration
		1645	Event->io (fd => IO::AIO::poll_fileno,
		1646	poll => 'r',
		1647	cb => \&IO::AIO::poll_cb);
		1648
		1649	# Glib/Gtk2 integration
		1650	add_watch Glib::IO IO::AIO::poll_fileno,
		1651	in => sub { IO::AIO::poll_cb; 1 };
		1652
		1653	# Tk integration
		1654	Tk::Event::IO->fileevent (IO::AIO::poll_fileno, "",
		1655	readable => \&IO::AIO::poll_cb);
		1656
		1657	# Danga::Socket integration
		1658	Danga::Socket->AddOtherFds (IO::AIO::poll_fileno =>
		1659	\&IO::AIO::poll_cb);
1124		1660
1125	=head2 FORK BEHAVIOUR	1661	=head2 FORK BEHAVIOUR
1126		1662
1127	This module should do "the right thing" when the process using it forks:	1663	This module should do "the right thing" when the process using it forks:
1128		1664
…		…
1146	bytes of memory. In addition, stat requests need a stat buffer (possibly	1682	bytes of memory. In addition, stat requests need a stat buffer (possibly
1147	a few hundred bytes), readdir requires a result buffer and so on. Perl	1683	a few hundred bytes), readdir requires a result buffer and so on. Perl
1148	scalars and other data passed into aio requests will also be locked and	1684	scalars and other data passed into aio requests will also be locked and
1149	will consume memory till the request has entered the done state.	1685	will consume memory till the request has entered the done state.
1150		1686
1151	This is now awfully much, so queuing lots of requests is not usually a	1687	This is not awfully much, so queuing lots of requests is not usually a
1152	problem.	1688	problem.
1153		1689
1154	Per-thread usage:	1690	Per-thread usage:
1155		1691
1156	In the execution phase, some aio requests require more memory for	1692	In the execution phase, some aio requests require more memory for
…		…
1161		1697
1162	Known bugs will be fixed in the next release.	1698	Known bugs will be fixed in the next release.
1163		1699
1164	=head1 SEE ALSO	1700	=head1 SEE ALSO
1165		1701
1166	L<Coro::AIO>.	1702	L<AnyEvent::AIO> for easy integration into event loops, L<Coro::AIO> for a
		1703	more natural syntax.
1167		1704
1168	=head1 AUTHOR	1705	=head1 AUTHOR
1169		1706
1170	Marc Lehmann <schmorp@schmorp.de>	1707	Marc Lehmann <schmorp@schmorp.de>
1171	http://home.schmorp.de/	1708	http://home.schmorp.de/

Diff Legend

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