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

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.105 by root, Sun Mar 25 00:20:27 2007 UTC vs.
Revision 1.173 by root, Thu Jan 7 20:25:57 2010 UTC

…		…
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 (EV, Event, Glib, Tk, POE, urxvt, pureperl...)
		32	use AnyEvent::AIO;
		33
31	# AnyEvent integration	34	# EV integration
32	open my $fh, "<&=" . IO::AIO::poll_fileno or die "$!";	35	my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
33	my $w = AnyEvent->io (fh => $fh, poll => 'r', cb => sub { IO::AIO::poll_cb });
34		36
35	# Event integration	37	# Event integration
36	Event->io (fd => IO::AIO::poll_fileno,	38	Event->io (fd => IO::AIO::poll_fileno,
37	poll => 'r',	39	poll => 'r',
38	cb => \&IO::AIO::poll_cb);	40	cb => \&IO::AIO::poll_cb);
…		…
50	\&IO::AIO::poll_cb);	52	\&IO::AIO::poll_cb);
51		53
52	=head1 DESCRIPTION	54	=head1 DESCRIPTION
53		55
54	This module implements asynchronous I/O using whatever means your	56	This module implements asynchronous I/O using whatever means your
55	operating system supports.	57	operating system supports. It is implemented as an interface to C<libeio>
		58	(L<http://software.schmorp.de/pkg/libeio.html>).
56		59
57	Asynchronous means that operations that can normally block your program	60	Asynchronous means that operations that can normally block your program
58	(e.g. reading from disk) will be done asynchronously: the operation	61	(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	62	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	63	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	65	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	66	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	67	on a RAID volume or over NFS when you do a number of stat operations
65	concurrently.	68	concurrently.
66		69
67	While most of this works on all types of file descriptors (for example	70	While most of this works on all types of file descriptors (for
68	sockets), using these functions on file descriptors that support	71	example sockets), using these functions on file descriptors that
69	nonblocking operation (again, sockets, pipes etc.) is very inefficient or	72	support nonblocking operation (again, sockets, pipes etc.) is
70	might not work (aio_read fails on sockets/pipes/fifos). Use an event loop	73	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	74	module): IO::AIO will naturally fit into such an event loop itself.
72	into such an event loop itself.
73		75
74	In this version, a number of threads are started that execute your	76	In this version, a number of threads are started that execute your
75	requests and signal their completion. You don't need thread support	77	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	78	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	79	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	81	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	82	files currently, for example), and they would only support aio_read and
81	aio_write, so the remaining functionality would have to be implemented	83	aio_write, so the remaining functionality would have to be implemented
82	using threads anyway.	84	using threads anyway.
83		85
84	Although the module will work with in the presence of other (Perl-)	86	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	87	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	88	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.	89	call C<poll_cb> (or other C<aio_> functions) recursively.
88		90
89	=head2 EXAMPLE	91	=head2 EXAMPLE
90		92
91	This is a simple example that uses the Event module and loads	93	This is a simple example that uses the EV module and loads
92	F</etc/passwd> asynchronously:	94	F</etc/passwd> asynchronously:
93		95
94	use Fcntl;	96	use Fcntl;
95	use Event;	97	use EV;
96	use IO::AIO;	98	use IO::AIO;
97		99
98	# register the IO::AIO callback with Event	100	# register the IO::AIO callback with EV
99	Event->io (fd => IO::AIO::poll_fileno,	101	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		102
103	# queue the request to open /etc/passwd	103	# queue the request to open /etc/passwd
104	aio_open "/etc/passwd", O_RDONLY, 0, sub {	104	aio_open "/etc/passwd", O_RDONLY, 0, sub {
105	my $fh = shift	105	my $fh = shift
106	or die "error while opening: $!";	106	or die "error while opening: $!";
…		…
118		118
119	# file contents now in $contents	119	# file contents now in $contents
120	print $contents;	120	print $contents;
121		121
122	# exit event loop and program	122	# exit event loop and program
123	Event::unloop;	123	EV::unloop;
124	};	124	};
125	};	125	};
126		126
127	# possibly queue up other requests, or open GUI windows,	127	# possibly queue up other requests, or open GUI windows,
128	# check for sockets etc. etc.	128	# check for sockets etc. etc.
129		129
130	# process events as long as there are some:	130	# process events as long as there are some:
131	Event::loop;	131	EV::loop;
132		132
133	=head1 REQUEST ANATOMY AND LIFETIME	133	=head1 REQUEST ANATOMY AND LIFETIME
134		134
135	Every C<aio_*> function creates a request. which is a C data structure not	135	Every C<aio_*> function creates a request. which is a C data structure not
136	directly visible to Perl.	136	directly visible to Perl.
…		…
184		184
185	=cut	185	=cut
186		186
187	package IO::AIO;	187	package IO::AIO;
188		188
189	no warnings;	189	use Carp ();
190	use strict 'vars';	190
		191	use common::sense;
191		192
192	use base 'Exporter';	193	use base 'Exporter';
193		194
194	BEGIN {	195	BEGIN {
195	our $VERSION = '2.33';	196	our $VERSION = '3.5';
196		197
197	our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close aio_stat	198	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	199	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	200	aio_scandir aio_symlink aio_readlink aio_sync aio_fsync
		201	aio_fdatasync aio_sync_file_range aio_pathsync aio_readahead
		202	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);	203	aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown
		204	aio_chmod aio_utime aio_truncate
		205	aio_msync aio_mtouch aio_statvfs);
		206
201	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice aio_block));	207	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));
202	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush	208	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush
203	min_parallel max_parallel max_idle	209	min_parallel max_parallel max_idle
204	nreqs nready npending nthreads	210	nreqs nready npending nthreads
205	max_poll_time max_poll_reqs);	211	max_poll_time max_poll_reqs
		212	sendfile fadvise);
		213
		214	push @AIO_REQ, qw(aio_busy); # not exported
206		215
207	@IO::AIO::GRP::ISA = 'IO::AIO::REQ';	216	@IO::AIO::GRP::ISA = 'IO::AIO::REQ';
208		217
209	require XSLoader;	218	require XSLoader;
210	XSLoader::load ("IO::AIO", $VERSION);	219	XSLoader::load ("IO::AIO", $VERSION);
…		…
217	All the C<aio_*> calls are more or less thin wrappers around the syscall	226	All the C<aio_*> calls are more or less thin wrappers around the syscall
218	with the same name (sans C<aio_>). The arguments are similar or identical,	227	with the same name (sans C<aio_>). The arguments are similar or identical,
219	and they all accept an additional (and optional) C<$callback> argument	228	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	229	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	230	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	231	perl, which usually delivers "false") as its sole argument after the given
223	syscall has been executed asynchronously.	232	syscall has been executed asynchronously.
224		233
225	All functions expecting a filehandle keep a copy of the filehandle	234	All functions expecting a filehandle keep a copy of the filehandle
226	internally until the request has finished.	235	internally until the request has finished.
227		236
…		…
241	your pathnames to the locale (or other) encoding in effect in the user	250	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)	251	environment, d) use Glib::filename_from_unicode on unicode filenames or e)
243	use something else to ensure your scalar has the correct contents.	252	use something else to ensure your scalar has the correct contents.
244		253
245	This works, btw. independent of the internal UTF-8 bit, which IO::AIO	254	This works, btw. independent of the internal UTF-8 bit, which IO::AIO
246	handles correctly wether it is set or not.	255	handles correctly whether it is set or not.
247		256
248	=over 4	257	=over 4
249		258
250	=item $prev_pri = aioreq_pri [$pri]	259	=item $prev_pri = aioreq_pri [$pri]
251		260
…		…
271	aio_read $_[0], ..., sub {	280	aio_read $_[0], ..., sub {
272	...	281	...
273	};	282	};
274	};	283	};
275		284
		285
276	=item aioreq_nice $pri_adjust	286	=item aioreq_nice $pri_adjust
277		287
278	Similar to C<aioreq_pri>, but subtracts the given value from the current	288	Similar to C<aioreq_pri>, but subtracts the given value from the current
279	priority, so the effect is cumulative.	289	priority, so the effect is cumulative.
		290
280		291
281	=item aio_open $pathname, $flags, $mode, $callback->($fh)	292	=item aio_open $pathname, $flags, $mode, $callback->($fh)
282		293
283	Asynchronously open or create a file and call the callback with a newly	294	Asynchronously open or create a file and call the callback with a newly
284	created filehandle for the file.	295	created filehandle for the file.
…		…
305	} else {	316	} else {
306	die "open failed: $!\n";	317	die "open failed: $!\n";
307	}	318	}
308	};	319	};
309		320
		321
310	=item aio_close $fh, $callback->($status)	322	=item aio_close $fh, $callback->($status)
311		323
312	Asynchronously close a file and call the callback with the result	324	Asynchronously close a file and call the callback with the result
313	code. I<WARNING:> although accepted, you should not pass in a perl	325	code.
314	filehandle here, as perl will likely close the file descriptor another
315	time when the filehandle is destroyed. Normally, you can safely call perls
316	C<close> or just let filehandles go out of scope.
317		326
318	This is supposed to be a bug in the API, so that might change. It's	327	Unfortunately, you can't do this to perl. Perl I<insists> very strongly on
319	therefore best to avoid this function.	328	closing the file descriptor associated with the filehandle itself.
		329
		330	Therefore, C<aio_close> will not close the filehandle - instead it will
		331	use dup2 to overwrite the file descriptor with the write-end of a pipe
		332	(the pipe fd will be created on demand and will be cached).
		333
		334	Or in other words: the file descriptor will be closed, but it will not be
		335	free for reuse until the perl filehandle is closed.
		336
		337	=cut
320		338
321	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	339	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
322		340
323	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	341	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
324		342
325	Reads or writes C<length> bytes from the specified C<fh> and C<offset>	343	Reads or writes C<$length> bytes from or to the specified C<$fh> and
326	into the scalar given by C<data> and offset C<dataoffset> and calls the	344	C<$offset> into the scalar given by C<$data> and offset C<$dataoffset>
327	callback without the actual number of bytes read (or -1 on error, just	345	and calls the callback without the actual number of bytes read (or -1 on
328	like the syscall).	346	error, just like the syscall).
		347
		348	C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to
		349	offset plus the actual number of bytes read.
		350
		351	If C<$offset> is undefined, then the current file descriptor offset will
		352	be used (and updated), otherwise the file descriptor offset will not be
		353	changed by these calls.
		354
		355	If C<$length> is undefined in C<aio_write>, use the remaining length of
		356	C<$data>.
		357
		358	If C<$dataoffset> is less than zero, it will be counted from the end of
		359	C<$data>.
329		360
330	The C<$data> scalar I<MUST NOT> be modified in any way while the request	361	The C<$data> scalar I<MUST NOT> be modified in any way while the request
331	is outstanding. Modifying it can result in segfaults or WW3 (if the	362	is outstanding. Modifying it can result in segfaults or World War III (if
332	necessary/optional hardware is installed).	363	the necessary/optional hardware is installed).
333		364
334	Example: Read 15 bytes at offset 7 into scalar C<$buffer>, starting at	365	Example: Read 15 bytes at offset 7 into scalar C<$buffer>, starting at
335	offset C<0> within the scalar:	366	offset C<0> within the scalar:
336		367
337	aio_read $fh, 7, 15, $buffer, 0, sub {	368	aio_read $fh, 7, 15, $buffer, 0, sub {
338	$_[0] > 0 or die "read error: $!";	369	$_[0] > 0 or die "read error: $!";
339	print "read $_[0] bytes: <$buffer>\n";	370	print "read $_[0] bytes: <$buffer>\n";
340	};	371	};
		372
341		373
342	=item aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)	374	=item aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
343		375
344	Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts	376	Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts
345	reading at byte offset C<$in_offset>, and starts writing at the current	377	reading at byte offset C<$in_offset>, and starts writing at the current
…		…
349		381
350	This call tries to make use of a native C<sendfile> syscall to provide	382	This call tries to make use of a native C<sendfile> syscall to provide
351	zero-copy operation. For this to work, C<$out_fh> should refer to a	383	zero-copy operation. For this to work, C<$out_fh> should refer to a
352	socket, and C<$in_fh> should refer to mmap'able file.	384	socket, and C<$in_fh> should refer to mmap'able file.
353		385
354	If the native sendfile call fails or is not implemented, it will be	386	If a native sendfile cannot be found or it fails with C<ENOSYS>,
		387	C<ENOTSUP>, C<EOPNOTSUPP>, C<EAFNOSUPPORT>, C<EPROTOTYPE> or C<ENOTSOCK>,
355	emulated, so you can call C<aio_sendfile> on any type of filehandle	388	it will be emulated, so you can call C<aio_sendfile> on any type of
356	regardless of the limitations of the operating system.	389	filehandle regardless of the limitations of the operating system.
357		390
358	Please note, however, that C<aio_sendfile> can read more bytes from	391	Please note, however, that C<aio_sendfile> can read more bytes from
359	C<$in_fh> than are written, and there is no way to find out how many	392	C<$in_fh> than are written, and there is no way to find out how many
360	bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only	393	bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only
361	provides the number of bytes written to C<$out_fh>. Only if the result	394	provides the number of bytes written to C<$out_fh>. Only if the result
362	value equals C<$length> one can assume that C<$length> bytes have been	395	value equals C<$length> one can assume that C<$length> bytes have been
363	read.	396	read.
		397
364		398
365	=item aio_readahead $fh,$offset,$length, $callback->($retval)	399	=item aio_readahead $fh,$offset,$length, $callback->($retval)
366		400
367	C<aio_readahead> populates the page cache with data from a file so that	401	C<aio_readahead> populates the page cache with data from a file so that
368	subsequent reads from that file will not block on disk I/O. The C<$offset>	402	subsequent reads from that file will not block on disk I/O. The C<$offset>
…		…
374	file. The current file offset of the file is left unchanged.	408	file. The current file offset of the file is left unchanged.
375		409
376	If that syscall doesn't exist (likely if your OS isn't Linux) it will be	410	If that syscall doesn't exist (likely if your OS isn't Linux) it will be
377	emulated by simply reading the data, which would have a similar effect.	411	emulated by simply reading the data, which would have a similar effect.
378		412
		413
379	=item aio_stat $fh_or_path, $callback->($status)	414	=item aio_stat $fh_or_path, $callback->($status)
380		415
381	=item aio_lstat $fh, $callback->($status)	416	=item aio_lstat $fh, $callback->($status)
382		417
383	Works like perl's C<stat> or C<lstat> in void context. The callback will	418	Works like perl's C<stat> or C<lstat> in void context. The callback will
…		…
396	aio_stat "/etc/passwd", sub {	431	aio_stat "/etc/passwd", sub {
397	$_[0] and die "stat failed: $!";	432	$_[0] and die "stat failed: $!";
398	print "size is ", -s _, "\n";	433	print "size is ", -s _, "\n";
399	};	434	};
400		435
		436
		437	=item aio_statvfs $fh_or_path, $callback->($statvfs)
		438
		439	Works like the POSIX C<statvfs> or C<fstatvfs> syscalls, depending on
		440	whether a file handle or path was passed.
		441
		442	On success, the callback is passed a hash reference with the following
		443	members: C<bsize>, C<frsize>, C<blocks>, C<bfree>, C<bavail>, C<files>,
		444	C<ffree>, C<favail>, C<fsid>, C<flag> and C<namemax>. On failure, C<undef>
		445	is passed.
		446
		447	The following POSIX IO::AIO::ST_* constants are defined: C<ST_RDONLY> and
		448	C<ST_NOSUID>.
		449
		450	The following non-POSIX IO::AIO::ST_* flag masks are defined to
		451	their correct value when available, or to C<0> on systems that do
		452	not support them: C<ST_NODEV>, C<ST_NOEXEC>, C<ST_SYNCHRONOUS>,
		453	C<ST_MANDLOCK>, C<ST_WRITE>, C<ST_APPEND>, C<ST_IMMUTABLE>, C<ST_NOATIME>,
		454	C<ST_NODIRATIME> and C<ST_RELATIME>.
		455
		456	Example: stat C</wd> and dump out the data if successful.
		457
		458	aio_statvfs "/wd", sub {
		459	my $f = $_[0]
		460	or die "statvfs: $!";
		461
		462	use Data::Dumper;
		463	say Dumper $f;
		464	};
		465
		466	# result:
		467	{
		468	bsize => 1024,
		469	bfree => 4333064312,
		470	blocks => 10253828096,
		471	files => 2050765568,
		472	flag => 4096,
		473	favail => 2042092649,
		474	bavail => 4333064312,
		475	ffree => 2042092649,
		476	namemax => 255,
		477	frsize => 1024,
		478	fsid => 1810
		479	}
		480
		481
		482	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
		483
		484	Works like perl's C<utime> function (including the special case of $atime
		485	and $mtime being undef). Fractional times are supported if the underlying
		486	syscalls support them.
		487
		488	When called with a pathname, uses utimes(2) if available, otherwise
		489	utime(2). If called on a file descriptor, uses futimes(2) if available,
		490	otherwise returns ENOSYS, so this is not portable.
		491
		492	Examples:
		493
		494	# set atime and mtime to current time (basically touch(1)):
		495	aio_utime "path", undef, undef;
		496	# set atime to current time and mtime to beginning of the epoch:
		497	aio_utime "path", time, undef; # undef==0
		498
		499
		500	=item aio_chown $fh_or_path, $uid, $gid, $callback->($status)
		501
		502	Works like perl's C<chown> function, except that C<undef> for either $uid
		503	or $gid is being interpreted as "do not change" (but -1 can also be used).
		504
		505	Examples:
		506
		507	# same as "chown root path" in the shell:
		508	aio_chown "path", 0, -1;
		509	# same as above:
		510	aio_chown "path", 0, undef;
		511
		512
		513	=item aio_truncate $fh_or_path, $offset, $callback->($status)
		514
		515	Works like truncate(2) or ftruncate(2).
		516
		517
		518	=item aio_chmod $fh_or_path, $mode, $callback->($status)
		519
		520	Works like perl's C<chmod> function.
		521
		522
401	=item aio_unlink $pathname, $callback->($status)	523	=item aio_unlink $pathname, $callback->($status)
402		524
403	Asynchronously unlink (delete) a file and call the callback with the	525	Asynchronously unlink (delete) a file and call the callback with the
404	result code.	526	result code.
405		527
		528
406	=item aio_mknod $path, $mode, $dev, $callback->($status)	529	=item aio_mknod $path, $mode, $dev, $callback->($status)
407		530
408	[EXPERIMENTAL]	531	[EXPERIMENTAL]
409		532
410	Asynchronously create a device node (or fifo). See mknod(2).	533	Asynchronously create a device node (or fifo). See mknod(2).
411		534
412	The only (POSIX-) portable way of calling this function is:	535	The only (POSIX-) portable way of calling this function is:
413		536
414	aio_mknod $path, IO::AIO::S_IFIFO \| $mode, 0, sub { ...	537	aio_mknod $path, IO::AIO::S_IFIFO \| $mode, 0, sub { ...
		538
415		539
416	=item aio_link $srcpath, $dstpath, $callback->($status)	540	=item aio_link $srcpath, $dstpath, $callback->($status)
417		541
418	Asynchronously create a new link to the existing object at C<$srcpath> at	542	Asynchronously create a new link to the existing object at C<$srcpath> at
419	the path C<$dstpath> and call the callback with the result code.	543	the path C<$dstpath> and call the callback with the result code.
420		544
		545
421	=item aio_symlink $srcpath, $dstpath, $callback->($status)	546	=item aio_symlink $srcpath, $dstpath, $callback->($status)
422		547
423	Asynchronously create a new symbolic link to the existing object at C<$srcpath> at	548	Asynchronously create a new symbolic link to the existing object at C<$srcpath> at
424	the path C<$dstpath> and call the callback with the result code.	549	the path C<$dstpath> and call the callback with the result code.
		550
425		551
426	=item aio_readlink $path, $callback->($link)	552	=item aio_readlink $path, $callback->($link)
427		553
428	Asynchronously read the symlink specified by C<$path> and pass it to	554	Asynchronously read the symlink specified by C<$path> and pass it to
429	the callback. If an error occurs, nothing or undef gets passed to the	555	the callback. If an error occurs, nothing or undef gets passed to the
430	callback.	556	callback.
431		557
		558
432	=item aio_rename $srcpath, $dstpath, $callback->($status)	559	=item aio_rename $srcpath, $dstpath, $callback->($status)
433		560
434	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as	561	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as
435	rename(2) and call the callback with the result code.	562	rename(2) and call the callback with the result code.
		563
436		564
437	=item aio_mkdir $pathname, $mode, $callback->($status)	565	=item aio_mkdir $pathname, $mode, $callback->($status)
438		566
439	Asynchronously mkdir (create) a directory and call the callback with	567	Asynchronously mkdir (create) a directory and call the callback with
440	the result code. C<$mode> will be modified by the umask at the time the	568	the result code. C<$mode> will be modified by the umask at the time the
441	request is executed, so do not change your umask.	569	request is executed, so do not change your umask.
442		570
		571
443	=item aio_rmdir $pathname, $callback->($status)	572	=item aio_rmdir $pathname, $callback->($status)
444		573
445	Asynchronously rmdir (delete) a directory and call the callback with the	574	Asynchronously rmdir (delete) a directory and call the callback with the
446	result code.	575	result code.
		576
447		577
448	=item aio_readdir $pathname, $callback->($entries)	578	=item aio_readdir $pathname, $callback->($entries)
449		579
450	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire	580	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire
451	directory (i.e. opendir + readdir + closedir). The entries will not be	581	directory (i.e. opendir + readdir + closedir). The entries will not be
452	sorted, and will B<NOT> include the C<.> and C<..> entries.	582	sorted, and will B<NOT> include the C<.> and C<..> entries.
453		583
454	The callback a single argument which is either C<undef> or an array-ref	584	The callback is passed a single argument which is either C<undef> or an
455	with the filenames.	585	array-ref with the filenames.
		586
		587
		588	=item aio_readdirx $pathname, $flags, $callback->($entries, $flags)
		589
		590	Quite similar to C<aio_readdir>, but the C<$flags> argument allows to tune
		591	behaviour and output format. In case of an error, C<$entries> will be
		592	C<undef>.
		593
		594	The flags are a combination of the following constants, ORed together (the
		595	flags will also be passed to the callback, possibly modified):
		596
		597	=over 4
		598
		599	=item IO::AIO::READDIR_DENTS
		600
		601	When this flag is off, then the callback gets an arrayref with of names
		602	only (as with C<aio_readdir>), otherwise it gets an arrayref with
		603	C<[$name, $type, $inode]> arrayrefs, each describing a single directory
		604	entry in more detail.
		605
		606	C<$name> is the name of the entry.
		607
		608	C<$type> is one of the C<IO::AIO::DT_xxx> constants:
		609
		610	C<IO::AIO::DT_UNKNOWN>, C<IO::AIO::DT_FIFO>, C<IO::AIO::DT_CHR>, C<IO::AIO::DT_DIR>,
		611	C<IO::AIO::DT_BLK>, C<IO::AIO::DT_REG>, C<IO::AIO::DT_LNK>, C<IO::AIO::DT_SOCK>,
		612	C<IO::AIO::DT_WHT>.
		613
		614	C<IO::AIO::DT_UNKNOWN> means just that: readdir does not know. If you need to
		615	know, you have to run stat yourself. Also, for speed reasons, the C<$type>
		616	scalars are read-only: you can not modify them.
		617
		618	C<$inode> is the inode number (which might not be exact on systems with 64
		619	bit inode numbers and 32 bit perls). This field has unspecified content on
		620	systems that do not deliver the inode information.
		621
		622	=item IO::AIO::READDIR_DIRS_FIRST
		623
		624	When this flag is set, then the names will be returned in an order where
		625	likely directories come first. This is useful when you need to quickly
		626	find directories, or you want to find all directories while avoiding to
		627	stat() each entry.
		628
		629	If the system returns type information in readdir, then this is used
		630	to find directories directly. Otherwise, likely directories are files
		631	beginning with ".", or otherwise files with no dots, of which files with
		632	short names are tried first.
		633
		634	=item IO::AIO::READDIR_STAT_ORDER
		635
		636	When this flag is set, then the names will be returned in an order
		637	suitable for stat()'ing each one. That is, when you plan to stat()
		638	all files in the given directory, then the returned order will likely
		639	be fastest.
		640
		641	If both this flag and C<IO::AIO::READDIR_DIRS_FIRST> are specified, then
		642	the likely dirs come first, resulting in a less optimal stat order.
		643
		644	=item IO::AIO::READDIR_FOUND_UNKNOWN
		645
		646	This flag should not be set when calling C<aio_readdirx>. Instead, it
		647	is being set by C<aio_readdirx>, when any of the C<$type>'s found were
		648	C<IO::AIO::DT_UNKNOWN>. The absense of this flag therefore indicates that all
		649	C<$type>'s are known, which can be used to speed up some algorithms.
		650
		651	=back
		652
456		653
457	=item aio_load $path, $data, $callback->($status)	654	=item aio_load $path, $data, $callback->($status)
458		655
459	This is a composite request that tries to fully load the given file into	656	This is a composite request that tries to fully load the given file into
460	memory. Status is the same as with aio_read.	657	memory. Status is the same as with aio_read.
461		658
462	=cut	659	=cut
463		660
464	sub aio_load($$;$) {	661	sub aio_load($$;$) {
465	aio_block {
466	my ($path, undef, $cb) = @_;	662	my ($path, undef, $cb) = @_;
467	my $data = \$_[1];	663	my $data = \$_[1];
468		664
469	my $pri = aioreq_pri;	665	my $pri = aioreq_pri;
470	my $grp = aio_group $cb;	666	my $grp = aio_group $cb;
		667
		668	aioreq_pri $pri;
		669	add $grp aio_open $path, O_RDONLY, 0, sub {
		670	my $fh = shift
		671	or return $grp->result (-1);
471		672
472	aioreq_pri $pri;	673	aioreq_pri $pri;
473	add $grp aio_open $path, O_RDONLY, 0, sub {
474	my $fh = shift
475	or return $grp->result (-1);
476
477	aioreq_pri $pri;
478	add $grp aio_read $fh, 0, (-s $fh), $$data, 0, sub {	674	add $grp aio_read $fh, 0, (-s $fh), $$data, 0, sub {
479	$grp->result ($_[0]);	675	$grp->result ($_[0]);
480	};
481	};	676	};
482
483	$grp
484	}	677	};
		678
		679	$grp
485	}	680	}
486		681
487	=item aio_copy $srcpath, $dstpath, $callback->($status)	682	=item aio_copy $srcpath, $dstpath, $callback->($status)
488		683
489	Try to copy the I<file> (directories not supported as either source or	684	Try to copy the I<file> (directories not supported as either source or
490	destination) from C<$srcpath> to C<$dstpath> and call the callback with	685	destination) from C<$srcpath> to C<$dstpath> and call the callback with
491	the C<0> (error) or C<-1> ok.	686	a status of C<0> (ok) or C<-1> (error, see C<$!>).
492		687
493	This is a composite request that it creates the destination file with	688	This is a composite request that creates the destination file with
494	mode 0200 and copies the contents of the source file into it using	689	mode 0200 and copies the contents of the source file into it using
495	C<aio_sendfile>, followed by restoring atime, mtime, access mode and	690	C<aio_sendfile>, followed by restoring atime, mtime, access mode and
496	uid/gid, in that order.	691	uid/gid, in that order.
497		692
498	If an error occurs, the partial destination file will be unlinked, if	693	If an error occurs, the partial destination file will be unlinked, if
…		…
500	errors are being ignored.	695	errors are being ignored.
501		696
502	=cut	697	=cut
503		698
504	sub aio_copy($$;$) {	699	sub aio_copy($$;$) {
505	aio_block {
506	my ($src, $dst, $cb) = @_;	700	my ($src, $dst, $cb) = @_;
507		701
508	my $pri = aioreq_pri;	702	my $pri = aioreq_pri;
509	my $grp = aio_group $cb;	703	my $grp = aio_group $cb;
510		704
511	aioreq_pri $pri;	705	aioreq_pri $pri;
512	add $grp aio_open $src, O_RDONLY, 0, sub {	706	add $grp aio_open $src, O_RDONLY, 0, sub {
513	if (my $src_fh = $_[0]) {	707	if (my $src_fh = $_[0]) {
514	my @stat = stat $src_fh;	708	my @stat = stat $src_fh; # hmm, might block over nfs?
515		709
516	aioreq_pri $pri;	710	aioreq_pri $pri;
517	add $grp aio_open $dst, O_CREAT \| O_WRONLY \| O_TRUNC, 0200, sub {	711	add $grp aio_open $dst, O_CREAT \| O_WRONLY \| O_TRUNC, 0200, sub {
518	if (my $dst_fh = $_[0]) {	712	if (my $dst_fh = $_[0]) {
519	aioreq_pri $pri;	713	aioreq_pri $pri;
520	add $grp aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub {	714	add $grp aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub {
521	if ($_[0] == $stat[7]) {	715	if ($_[0] == $stat[7]) {
522	$grp->result (0);	716	$grp->result (0);
523	close $src_fh;	717	close $src_fh;
524		718
525	# those should not normally block. should. should.
526	utime $stat[8], $stat[9], $dst;
527	chmod $stat[2] & 07777, $dst_fh;
528	chown $stat[4], $stat[5], $dst_fh;
529	close $dst_fh;
530	} else {	719	my $ch = sub {
531	$grp->result (-1);
532	close $src_fh;
533	close $dst_fh;
534
535	aioreq $pri;	720	aioreq_pri $pri;
		721	add $grp aio_chmod $dst_fh, $stat[2] & 07777, sub {
		722	aioreq_pri $pri;
		723	add $grp aio_chown $dst_fh, $stat[4], $stat[5], sub {
		724	aioreq_pri $pri;
536	add $grp aio_unlink $dst;	725	add $grp aio_close $dst_fh;
		726	}
		727	};
537	}	728	};
		729
		730	aioreq_pri $pri;
		731	add $grp aio_utime $dst_fh, $stat[8], $stat[9], sub {
		732	if ($_[0] < 0 && $! == ENOSYS) {
		733	aioreq_pri $pri;
		734	add $grp aio_utime $dst, $stat[8], $stat[9], $ch;
		735	} else {
		736	$ch->();
		737	}
		738	};
		739	} else {
		740	$grp->result (-1);
		741	close $src_fh;
		742	close $dst_fh;
		743
		744	aioreq $pri;
		745	add $grp aio_unlink $dst;
538	};	746	}
539	} else {
540	$grp->result (-1);
541	}	747	};
		748	} else {
		749	$grp->result (-1);
542	},	750	}
543
544	} else {
545	$grp->result (-1);
546	}	751	},
		752
		753	} else {
		754	$grp->result (-1);
547	};	755	}
548
549	$grp
550	}	756	};
		757
		758	$grp
551	}	759	}
552		760
553	=item aio_move $srcpath, $dstpath, $callback->($status)	761	=item aio_move $srcpath, $dstpath, $callback->($status)
554		762
555	Try to move the I<file> (directories not supported as either source or	763	Try to move the I<file> (directories not supported as either source or
556	destination) from C<$srcpath> to C<$dstpath> and call the callback with	764	destination) from C<$srcpath> to C<$dstpath> and call the callback with
557	the C<0> (error) or C<-1> ok.	765	a status of C<0> (ok) or C<-1> (error, see C<$!>).
558		766
559	This is a composite request that tries to rename(2) the file first. If	767	This is a composite request that tries to rename(2) the file first; if
560	rename files with C<EXDEV>, it copies the file with C<aio_copy> and, if	768	rename fails with C<EXDEV>, it copies the file with C<aio_copy> and, if
561	that is successful, unlinking the C<$srcpath>.	769	that is successful, unlinks the C<$srcpath>.
562		770
563	=cut	771	=cut
564		772
565	sub aio_move($$;$) {	773	sub aio_move($$;$) {
566	aio_block {
567	my ($src, $dst, $cb) = @_;	774	my ($src, $dst, $cb) = @_;
568		775
569	my $pri = aioreq_pri;	776	my $pri = aioreq_pri;
570	my $grp = aio_group $cb;	777	my $grp = aio_group $cb;
571		778
572	aioreq_pri $pri;	779	aioreq_pri $pri;
573	add $grp aio_rename $src, $dst, sub {	780	add $grp aio_rename $src, $dst, sub {
574	if ($_[0] && $! == EXDEV) {	781	if ($_[0] && $! == EXDEV) {
575	aioreq_pri $pri;	782	aioreq_pri $pri;
576	add $grp aio_copy $src, $dst, sub {	783	add $grp aio_copy $src, $dst, sub {
577	$grp->result ($_[0]);
578
579	if (!$_[0]) {
580	aioreq_pri $pri;
581	add $grp aio_unlink $src;
582	}
583	};
584	} else {
585	$grp->result ($_[0]);	784	$grp->result ($_[0]);
		785
		786	if (!$_[0]) {
		787	aioreq_pri $pri;
		788	add $grp aio_unlink $src;
		789	}
586	}	790	};
		791	} else {
		792	$grp->result ($_[0]);
587	};	793	}
588
589	$grp
590	}	794	};
		795
		796	$grp
591	}	797	}
592		798
593	=item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)	799	=item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
594		800
595	Scans a directory (similar to C<aio_readdir>) but additionally tries to	801	Scans a directory (similar to C<aio_readdir>) but additionally tries to
…		…
615		821
616	Implementation notes.	822	Implementation notes.
617		823
618	The C<aio_readdir> cannot be avoided, but C<stat()>'ing every entry can.	824	The C<aio_readdir> cannot be avoided, but C<stat()>'ing every entry can.
619		825
		826	If readdir returns file type information, then this is used directly to
		827	find directories.
		828
620	After reading the directory, the modification time, size etc. of the	829	Otherwise, after reading the directory, the modification time, size etc.
621	directory before and after the readdir is checked, and if they match (and	830	of the directory before and after the readdir is checked, and if they
622	isn't the current time), the link count will be used to decide how many	831	match (and isn't the current time), the link count will be used to decide
623	entries are directories (if >= 2). Otherwise, no knowledge of the number	832	how many entries are directories (if >= 2). Otherwise, no knowledge of the
624	of subdirectories will be assumed.	833	number of subdirectories will be assumed.
625		834
626	Then entries will be sorted into likely directories (everything without	835	Then entries will be sorted into likely directories a non-initial dot
627	a non-initial dot currently) and likely non-directories (everything	836	currently) and likely non-directories (see C<aio_readdirx>). Then every
628	else). Then every entry plus an appended C</.> will be C<stat>'ed,	837	entry plus an appended C</.> will be C<stat>'ed, likely directories first,
629	likely directories first. If that succeeds, it assumes that the entry	838	in order of their inode numbers. If that succeeds, it assumes that the
630	is a directory or a symlink to directory (which will be checked	839	entry is a directory or a symlink to directory (which will be checked
631	seperately). This is often faster than stat'ing the entry itself because	840	seperately). This is often faster than stat'ing the entry itself because
632	filesystems might detect the type of the entry without reading the inode	841	filesystems might detect the type of the entry without reading the inode
633	data (e.g. ext2fs filetype feature).	842	data (e.g. ext2fs filetype feature), even on systems that cannot return
		843	the filetype information on readdir.
634		844
635	If the known number of directories (link count - 2) has been reached, the	845	If the known number of directories (link count - 2) has been reached, the
636	rest of the entries is assumed to be non-directories.	846	rest of the entries is assumed to be non-directories.
637		847
638	This only works with certainty on POSIX (= UNIX) filesystems, which	848	This only works with certainty on POSIX (= UNIX) filesystems, which
…		…
643	directory counting heuristic.	853	directory counting heuristic.
644		854
645	=cut	855	=cut
646		856
647	sub aio_scandir($$;$) {	857	sub aio_scandir($$;$) {
648	aio_block {
649	my ($path, $maxreq, $cb) = @_;	858	my ($path, $maxreq, $cb) = @_;
650		859
651	my $pri = aioreq_pri;	860	my $pri = aioreq_pri;
652		861
653	my $grp = aio_group $cb;	862	my $grp = aio_group $cb;
654		863
655	$maxreq = 4 if $maxreq <= 0;	864	$maxreq = 4 if $maxreq <= 0;
656		865
657	# stat once	866	# stat once
		867	aioreq_pri $pri;
		868	add $grp aio_stat $path, sub {
		869	return $grp->result () if $_[0];
		870	my $now = time;
		871	my $hash1 = join ":", (stat _)[0,1,3,7,9];
		872
		873	# read the directory entries
658	aioreq_pri $pri;	874	aioreq_pri $pri;
659	add $grp aio_stat $path, sub {	875	add $grp aio_readdirx $path, READDIR_DIRS_FIRST, sub {
		876	my $entries = shift
660	return $grp->result () if $_[0];	877	or return $grp->result ();
661	my $now = time;
662	my $hash1 = join ":", (stat _)[0,1,3,7,9];
663		878
664	# read the directory entries	879	# stat the dir another time
665	aioreq_pri $pri;	880	aioreq_pri $pri;
666	add $grp aio_readdir $path, sub {
667	my $entries = shift
668	or return $grp->result ();
669
670	# stat the dir another time
671	aioreq_pri $pri;
672	add $grp aio_stat $path, sub {	881	add $grp aio_stat $path, sub {
673	my $hash2 = join ":", (stat _)[0,1,3,7,9];	882	my $hash2 = join ":", (stat _)[0,1,3,7,9];
674		883
675	my $ndirs;	884	my $ndirs;
676		885
677	# take the slow route if anything looks fishy	886	# take the slow route if anything looks fishy
678	if ($hash1 ne $hash2 or (stat _)[9] == $now) {	887	if ($hash1 ne $hash2 or (stat _)[9] == $now) {
679	$ndirs = -1;	888	$ndirs = -1;
680	} else {	889	} else {
681	# if nlink == 2, we are finished	890	# if nlink == 2, we are finished
682	# on non-posix-fs's, we rely on nlink < 2	891	# for non-posix-fs's, we rely on nlink < 2
683	$ndirs = (stat _)[3] - 2	892	$ndirs = (stat _)[3] - 2
684	or return $grp->result ([], $entries);	893	or return $grp->result ([], $entries);
685	}	894	}
686		895
687	# sort into likely dirs and likely nondirs
688	# dirs == files without ".", short entries first
689	$entries = [map $_->[0],
690	sort { $b->[1] cmp $a->[1] }
691	map [$_, sprintf "%s%04d", (/.\./ ? "1" : "0"), length],
692	@$entries];
693
694	my (@dirs, @nondirs);	896	my (@dirs, @nondirs);
695		897
696	my $statgrp = add $grp aio_group sub {	898	my $statgrp = add $grp aio_group sub {
697	$grp->result (\@dirs, \@nondirs);	899	$grp->result (\@dirs, \@nondirs);
698	};	900	};
699		901
700	limit $statgrp $maxreq;	902	limit $statgrp $maxreq;
701	feed $statgrp sub {	903	feed $statgrp sub {
702	return unless @$entries;	904	return unless @$entries;
703	my $entry = pop @$entries;	905	my $entry = shift @$entries;
704		906
705	aioreq_pri $pri;	907	aioreq_pri $pri;
706	add $statgrp aio_stat "$path/$entry/.", sub {	908	add $statgrp aio_stat "$path/$entry/.", sub {
707	if ($_[0] < 0) {	909	if ($_[0] < 0) {
708	push @nondirs, $entry;	910	push @nondirs, $entry;
709	} else {	911	} else {
710	# need to check for real directory	912	# need to check for real directory
711	aioreq_pri $pri;	913	aioreq_pri $pri;
712	add $statgrp aio_lstat "$path/$entry", sub {	914	add $statgrp aio_lstat "$path/$entry", sub {
713	if (-d _) {	915	if (-d _) {
714	push @dirs, $entry;	916	push @dirs, $entry;
715		917
716	unless (--$ndirs) {	918	unless (--$ndirs) {
717	push @nondirs, @$entries;	919	push @nondirs, @$entries;
718	feed $statgrp;	920	feed $statgrp;
719	}
720	} else {
721	push @nondirs, $entry;
722	}	921	}
		922	} else {
		923	push @nondirs, $entry;
723	}	924	}
724	}	925	}
725	};	926	}
726	};	927	};
727	};	928	};
728	};	929	};
729	};	930	};
730
731	$grp
732	}	931	};
		932
		933	$grp
733	}	934	}
734		935
735	=item aio_rmtree $path, $callback->($status)	936	=item aio_rmtree $path, $callback->($status)
736		937
737	Delete a directory tree starting (and including) C<$path>, return the	938	Delete a directory tree starting (and including) C<$path>, return the
…		…
741		942
742	=cut	943	=cut
743		944
744	sub aio_rmtree;	945	sub aio_rmtree;
745	sub aio_rmtree($;$) {	946	sub aio_rmtree($;$) {
746	aio_block {
747	my ($path, $cb) = @_;	947	my ($path, $cb) = @_;
748		948
749	my $pri = aioreq_pri;	949	my $pri = aioreq_pri;
750	my $grp = aio_group $cb;	950	my $grp = aio_group $cb;
751		951
752	aioreq_pri $pri;	952	aioreq_pri $pri;
753	add $grp aio_scandir $path, 0, sub {	953	add $grp aio_scandir $path, 0, sub {
754	my ($dirs, $nondirs) = @_;	954	my ($dirs, $nondirs) = @_;
755		955
756	my $dirgrp = aio_group sub {	956	my $dirgrp = aio_group sub {
757	add $grp aio_rmdir $path, sub {	957	add $grp aio_rmdir $path, sub {
758	$grp->result ($_[0]);	958	$grp->result ($_[0]);
759	};
760	};	959	};
761
762	(aioreq_pri $pri), add $dirgrp aio_rmtree "$path/$_" for @$dirs;
763	(aioreq_pri $pri), add $dirgrp aio_unlink "$path/$_" for @$nondirs;
764
765	add $grp $dirgrp;
766	};	960	};
767		961
768	$grp	962	(aioreq_pri $pri), add $dirgrp aio_rmtree "$path/$_" for @$dirs;
		963	(aioreq_pri $pri), add $dirgrp aio_unlink "$path/$_" for @$nondirs;
		964
		965	add $grp $dirgrp;
769	}	966	};
		967
		968	$grp
770	}	969	}
		970
		971	=item aio_sync $callback->($status)
		972
		973	Asynchronously call sync and call the callback when finished.
771		974
772	=item aio_fsync $fh, $callback->($status)	975	=item aio_fsync $fh, $callback->($status)
773		976
774	Asynchronously call fsync on the given filehandle and call the callback	977	Asynchronously call fsync on the given filehandle and call the callback
775	with the fsync result code.	978	with the fsync result code.
…		…
779	Asynchronously call fdatasync on the given filehandle and call the	982	Asynchronously call fdatasync on the given filehandle and call the
780	callback with the fdatasync result code.	983	callback with the fdatasync result code.
781		984
782	If this call isn't available because your OS lacks it or it couldn't be	985	If this call isn't available because your OS lacks it or it couldn't be
783	detected, it will be emulated by calling C<fsync> instead.	986	detected, it will be emulated by calling C<fsync> instead.
		987
		988	=item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
		989
		990	Sync the data portion of the file specified by C<$offset> and C<$length>
		991	to disk (but NOT the metadata), by calling the Linux-specific
		992	sync_file_range call. If sync_file_range is not available or it returns
		993	ENOSYS, then fdatasync or fsync is being substituted.
		994
		995	C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>,
		996	C<IO::AIO::SYNC_FILE_RANGE_WRITE> and
		997	C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range
		998	manpage for details.
		999
		1000	=item aio_pathsync $path, $callback->($status)
		1001
		1002	This request tries to open, fsync and close the given path. This is a
		1003	composite request intended to sync directories after directory operations
		1004	(E.g. rename). This might not work on all operating systems or have any
		1005	specific effect, but usually it makes sure that directory changes get
		1006	written to disc. It works for anything that can be opened for read-only,
		1007	not just directories.
		1008
		1009	Future versions of this function might fall back to other methods when
		1010	C<fsync> on the directory fails (such as calling C<sync>).
		1011
		1012	Passes C<0> when everything went ok, and C<-1> on error.
		1013
		1014	=cut
		1015
		1016	sub aio_pathsync($;$) {
		1017	my ($path, $cb) = @_;
		1018
		1019	my $pri = aioreq_pri;
		1020	my $grp = aio_group $cb;
		1021
		1022	aioreq_pri $pri;
		1023	add $grp aio_open $path, O_RDONLY, 0, sub {
		1024	my ($fh) = @_;
		1025	if ($fh) {
		1026	aioreq_pri $pri;
		1027	add $grp aio_fsync $fh, sub {
		1028	$grp->result ($_[0]);
		1029
		1030	aioreq_pri $pri;
		1031	add $grp aio_close $fh;
		1032	};
		1033	} else {
		1034	$grp->result (-1);
		1035	}
		1036	};
		1037
		1038	$grp
		1039	}
		1040
		1041	=item aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
		1042
		1043	This is a rather advanced IO::AIO call, which only works on mmap(2)ed
		1044	scalars (see the L<Sys::Mmap> or L<Mmap> modules for details on this, note
		1045	that the scalar must only be modified in-place while an aio operation is
		1046	pending on it).
		1047
		1048	It calls the C<msync> function of your OS, if available, with the memory
		1049	area starting at C<$offset> in the string and ending C<$length> bytes
		1050	later. If C<$length> is negative, counts from the end, and if C<$length>
		1051	is C<undef>, then it goes till the end of the string. The flags can be
		1052	a combination of C<IO::AIO::MS_ASYNC>, C<IO::AIO::MS_INVALIDATE> and
		1053	C<IO::AIO::MS_SYNC>.
		1054
		1055	=item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
		1056
		1057	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
		1058	scalars.
		1059
		1060	It touches (reads or writes) all memory pages in the specified
		1061	range inside the scalar. All caveats and parameters are the same
		1062	as for C<aio_msync>, above, except for flags, which must be either
		1063	C<0> (which reads all pages and ensures they are instantiated) or
		1064	C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and
		1065	writing an octet from it, which dirties the page).
784		1066
785	=item aio_group $callback->(...)	1067	=item aio_group $callback->(...)
786		1068
787	This is a very special aio request: Instead of doing something, it is a	1069	This is a very special aio request: Instead of doing something, it is a
788	container for other aio requests, which is useful if you want to bundle	1070	container for other aio requests, which is useful if you want to bundle
…		…
838	=item cancel $req	1120	=item cancel $req
839		1121
840	Cancels the request, if possible. Has the effect of skipping execution	1122	Cancels the request, if possible. Has the effect of skipping execution
841	when entering the B<execute> state and skipping calling the callback when	1123	when entering the B<execute> state and skipping calling the callback when
842	entering the the B<result> state, but will leave the request otherwise	1124	entering the the B<result> state, but will leave the request otherwise
843	untouched. That means that requests that currently execute will not be	1125	untouched (with the exception of readdir). That means that requests that
844	stopped and resources held by the request will not be freed prematurely.	1126	currently execute will not be stopped and resources held by the request
		1127	will not be freed prematurely.
845		1128
846	=item cb $req $callback->(...)	1129	=item cb $req $callback->(...)
847		1130
848	Replace (or simply set) the callback registered to the request.	1131	Replace (or simply set) the callback registered to the request.
849		1132
…		…
900	Their lifetime, simplified, looks like this: when they are empty, they	1183	Their lifetime, simplified, looks like this: when they are empty, they
901	will finish very quickly. If they contain only requests that are in the	1184	will finish very quickly. If they contain only requests that are in the
902	C<done> state, they will also finish. Otherwise they will continue to	1185	C<done> state, they will also finish. Otherwise they will continue to
903	exist.	1186	exist.
904		1187
905	That means after creating a group you have some time to add requests. And	1188	That means after creating a group you have some time to add requests
906	in the callbacks of those requests, you can add further requests to the	1189	(precisely before the callback has been invoked, which is only done within
907	group. And only when all those requests have finished will the the group	1190	the C<poll_cb>). And in the callbacks of those requests, you can add
908	itself finish.	1191	further requests to the group. And only when all those requests have
		1192	finished will the the group itself finish.
909		1193
910	=over 4	1194	=over 4
911		1195
912	=item add $grp ...	1196	=item add $grp ...
913		1197
…		…
922	=item $grp->cancel_subs	1206	=item $grp->cancel_subs
923		1207
924	Cancel all subrequests and clears any feeder, but not the group request	1208	Cancel all subrequests and clears any feeder, but not the group request
925	itself. Useful when you queued a lot of events but got a result early.	1209	itself. Useful when you queued a lot of events but got a result early.
926		1210
		1211	The group request will finish normally (you cannot add requests to the
		1212	group).
		1213
927	=item $grp->result (...)	1214	=item $grp->result (...)
928		1215
929	Set the result value(s) that will be passed to the group callback when all	1216	Set the result value(s) that will be passed to the group callback when all
930	subrequests have finished and set thre groups errno to the current value	1217	subrequests have finished and set the groups errno to the current value
931	of errno (just like calling C<errno> without an error number). By default,	1218	of errno (just like calling C<errno> without an error number). By default,
932	no argument will be passed and errno is zero.	1219	no argument will be passed and errno is zero.
933		1220
934	=item $grp->errno ([$errno])	1221	=item $grp->errno ([$errno])
935		1222
…		…
946	=item feed $grp $callback->($grp)	1233	=item feed $grp $callback->($grp)
947		1234
948	Sets a feeder/generator on this group: every group can have an attached	1235	Sets a feeder/generator on this group: every group can have an attached
949	generator that generates requests if idle. The idea behind this is that,	1236	generator that generates requests if idle. The idea behind this is that,
950	although you could just queue as many requests as you want in a group,	1237	although you could just queue as many requests as you want in a group,
951	this might starve other requests for a potentially long time. For	1238	this might starve other requests for a potentially long time. For example,
952	example, C<aio_scandir> might generate hundreds of thousands C<aio_stat>	1239	C<aio_scandir> might generate hundreds of thousands C<aio_stat> requests,
953	requests, delaying any later requests for a long time.	1240	delaying any later requests for a long time.
954		1241
955	To avoid this, and allow incremental generation of requests, you can	1242	To avoid this, and allow incremental generation of requests, you can
956	instead a group and set a feeder on it that generates those requests. The	1243	instead a group and set a feeder on it that generates those requests. The
957	feed callback will be called whenever there are few enough (see C<limit>,	1244	feed callback will be called whenever there are few enough (see C<limit>,
958	below) requests active in the group itself and is expected to queue more	1245	below) requests active in the group itself and is expected to queue more
…		…
962	not impose any limits).	1249	not impose any limits).
963		1250
964	If the feed does not queue more requests when called, it will be	1251	If the feed does not queue more requests when called, it will be
965	automatically removed from the group.	1252	automatically removed from the group.
966		1253
967	If the feed limit is C<0>, it will be set to C<2> automatically.	1254	If the feed limit is C<0> when this method is called, it will be set to
		1255	C<2> automatically.
968		1256
969	Example:	1257	Example:
970		1258
971	# stat all files in @files, but only ever use four aio requests concurrently:	1259	# stat all files in @files, but only ever use four aio requests concurrently:
972		1260
…		…
984	Sets the feeder limit for the group: The feeder will be called whenever	1272	Sets the feeder limit for the group: The feeder will be called whenever
985	the group contains less than this many requests.	1273	the group contains less than this many requests.
986		1274
987	Setting the limit to C<0> will pause the feeding process.	1275	Setting the limit to C<0> will pause the feeding process.
988		1276
		1277	The default value for the limit is C<0>, but note that setting a feeder
		1278	automatically bumps it up to C<2>.
		1279
989	=back	1280	=back
990		1281
991	=head2 SUPPORT FUNCTIONS	1282	=head2 SUPPORT FUNCTIONS
992		1283
993	=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION	1284	=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION
…		…
995	=over 4	1286	=over 4
996		1287
997	=item $fileno = IO::AIO::poll_fileno	1288	=item $fileno = IO::AIO::poll_fileno
998		1289
999	Return the I<request result pipe file descriptor>. This filehandle must be	1290	Return the I<request result pipe file descriptor>. This filehandle must be
1000	polled for reading by some mechanism outside this module (e.g. Event or	1291	polled for reading by some mechanism outside this module (e.g. EV, Glib,
1001	select, see below or the SYNOPSIS). If the pipe becomes readable you have	1292	select and so on, see below or the SYNOPSIS). If the pipe becomes readable
1002	to call C<poll_cb> to check the results.	1293	you have to call C<poll_cb> to check the results.
1003		1294
1004	See C<poll_cb> for an example.	1295	See C<poll_cb> for an example.
1005		1296
1006	=item IO::AIO::poll_cb	1297	=item IO::AIO::poll_cb
1007		1298
1008	Process some outstanding events on the result pipe. You have to call this	1299	Process some outstanding events on the result pipe. You have to call this
1009	regularly. Returns the number of events processed. Returns immediately	1300	regularly. Returns C<0> if all events could be processed, or C<-1> if it
		1301	returned earlier for whatever reason. Returns immediately when no events
1010	when no events are outstanding. The amount of events processed depends on	1302	are outstanding. The amount of events processed depends on the settings of
1011	the settings of C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>.	1303	C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>.
1012		1304
1013	If not all requests were processed for whatever reason, the filehandle	1305	If not all requests were processed for whatever reason, the filehandle
1014	will still be ready when C<poll_cb> returns.	1306	will still be ready when C<poll_cb> returns, so normally you don't have to
		1307	do anything special to have it called later.
1015		1308
1016	Example: Install an Event watcher that automatically calls	1309	Example: Install an Event watcher that automatically calls
1017	IO::AIO::poll_cb with high priority:	1310	IO::AIO::poll_cb with high priority (more examples can be found in the
		1311	SYNOPSIS section, at the top of this document):
1018		1312
1019	Event->io (fd => IO::AIO::poll_fileno,	1313	Event->io (fd => IO::AIO::poll_fileno,
1020	poll => 'r', async => 1,	1314	poll => 'r', async => 1,
1021	cb => \&IO::AIO::poll_cb);	1315	cb => \&IO::AIO::poll_cb);
1022		1316
…		…
1133		1427
1134	The default is probably ok in most situations, especially if thread	1428	The default is probably ok in most situations, especially if thread
1135	creation is fast. If thread creation is very slow on your system you might	1429	creation is fast. If thread creation is very slow on your system you might
1136	want to use larger values.	1430	want to use larger values.
1137		1431
1138	=item $oldmaxreqs = IO::AIO::max_outstanding $maxreqs	1432	=item IO::AIO::max_outstanding $maxreqs
1139		1433
1140	This is a very bad function to use in interactive programs because it	1434	This is a very bad function to use in interactive programs because it
1141	blocks, and a bad way to reduce concurrency because it is inexact: Better	1435	blocks, and a bad way to reduce concurrency because it is inexact: Better
1142	use an C<aio_group> together with a feed callback.	1436	use an C<aio_group> together with a feed callback.
1143		1437
1144	Sets the maximum number of outstanding requests to C<$nreqs>. If you	1438	Sets the maximum number of outstanding requests to C<$nreqs>. If you
1145	to queue up more than this number of requests, the next call to the	1439	do queue up more than this number of requests, the next call to the
1146	C<poll_cb> (and C<poll_some> and other functions calling C<poll_cb>)	1440	C<poll_cb> (and C<poll_some> and other functions calling C<poll_cb>)
1147	function will block until the limit is no longer exceeded.	1441	function will block until the limit is no longer exceeded.
1148		1442
1149	The default value is very large, so there is no practical limit on the	1443	The default value is very large, so there is no practical limit on the
1150	number of outstanding requests.	1444	number of outstanding requests.
1151		1445
1152	You can still queue as many requests as you want. Therefore,	1446	You can still queue as many requests as you want. Therefore,
1153	C<max_oustsanding> is mainly useful in simple scripts (with low values) or	1447	C<max_outstanding> is mainly useful in simple scripts (with low values) or
1154	as a stop gap to shield against fatal memory overflow (with large values).	1448	as a stop gap to shield against fatal memory overflow (with large values).
1155		1449
1156	=back	1450	=back
1157		1451
1158	=head3 STATISTICAL INFORMATION	1452	=head3 STATISTICAL INFORMATION
…		…
1179	Returns the number of requests currently in the pending state (executed,	1473	Returns the number of requests currently in the pending state (executed,
1180	but not yet processed by poll_cb).	1474	but not yet processed by poll_cb).
1181		1475
1182	=back	1476	=back
1183		1477
		1478	=head3 MISCELLANEOUS FUNCTIONS
		1479
		1480	IO::AIO implements some functions that might be useful, but are not
		1481	asynchronous.
		1482
		1483	=over 4
		1484
		1485	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
		1486
		1487	Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>,
		1488	but is blocking (this makes most sense if you know the input data is
		1489	likely cached already and the output filehandle is set to non-blocking
		1490	operations).
		1491
		1492	Returns the number of bytes copied, or C<-1> on error.
		1493
		1494	=item IO::AIO::fadvise $fh, $offset, $len, $advice
		1495
		1496	Simply calls the C<posix_fadvise> function (see it's
		1497	manpage for details). The following advice constants are
		1498	avaiable: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>,
		1499	C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>,
		1500	C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>.
		1501
		1502	On systems that do not implement C<posix_fadvise>, this function returns
		1503	ENOSYS, otherwise the return value of C<posix_fadvise>.
		1504
		1505	=back
		1506
1184	=cut	1507	=cut
1185
1186	# support function to convert a fd into a perl filehandle
1187	sub _fd2fh {
1188	return undef if $_[0] < 0;
1189
1190	# try to generate nice filehandles
1191	my $sym = "IO::AIO::fd#$_[0]";
1192	local *$sym;
1193
1194	open *$sym, "+<&=$_[0]" # usually works under any unix
1195	or open *$sym, "<&=$_[0]" # cygwin needs this
1196	or open *$sym, ">&=$_[0]" # or this
1197	or return undef;
1198
1199	*$sym
1200	}
1201		1508
1202	min_parallel 8;	1509	min_parallel 8;
1203		1510
1204	END { flush }	1511	END { flush }
1205		1512
…		…
1229	bytes of memory. In addition, stat requests need a stat buffer (possibly	1536	bytes of memory. In addition, stat requests need a stat buffer (possibly
1230	a few hundred bytes), readdir requires a result buffer and so on. Perl	1537	a few hundred bytes), readdir requires a result buffer and so on. Perl
1231	scalars and other data passed into aio requests will also be locked and	1538	scalars and other data passed into aio requests will also be locked and
1232	will consume memory till the request has entered the done state.	1539	will consume memory till the request has entered the done state.
1233		1540
1234	This is now awfully much, so queuing lots of requests is not usually a	1541	This is not awfully much, so queuing lots of requests is not usually a
1235	problem.	1542	problem.
1236		1543
1237	Per-thread usage:	1544	Per-thread usage:
1238		1545
1239	In the execution phase, some aio requests require more memory for	1546	In the execution phase, some aio requests require more memory for
…		…
1244		1551
1245	Known bugs will be fixed in the next release.	1552	Known bugs will be fixed in the next release.
1246		1553
1247	=head1 SEE ALSO	1554	=head1 SEE ALSO
1248		1555
1249	L<Coro::AIO>.	1556	L<AnyEvent::AIO> for easy integration into event loops, L<Coro::AIO> for a
		1557	more natural syntax.
1250		1558
1251	=head1 AUTHOR	1559	=head1 AUTHOR
1252		1560
1253	Marc Lehmann <schmorp@schmorp.de>	1561	Marc Lehmann <schmorp@schmorp.de>
1254	http://home.schmorp.de/	1562	http://home.schmorp.de/

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Comparing IO-AIO/AIO.pm (file contents): Revision 1.105 by root, Sun Mar 25 00:20:27 2007 UTC vs. Revision 1.173 by root, Thu Jan 7 20:25:57 2010 UTC

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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.105 by root, Sun Mar 25 00:20:27 2007 UTC vs.
Revision 1.173 by root, Thu Jan 7 20:25:57 2010 UTC