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

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.115 by root, Mon Sep 24 18:14:00 2007 UTC vs.
Revision 1.182 by root, Sun Sep 12 03:36:27 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
…		…
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	47	While most of this works on all types of file descriptors (for
68	example sockets), using these functions on file descriptors that	48	example sockets), using these functions on file descriptors that
69	support nonblocking operation (again, sockets, pipes etc.) is very	49	support nonblocking operation (again, sockets, pipes etc.) is
70	inefficient. Use an event loop for that (such as the L<Event\|Event>	50	very inefficient. Use an event loop for that (such as the L<EV>
71	module): IO::AIO will naturally fit into such an event loop itself.	51	module): IO::AIO will naturally fit into such an event loop itself.
72		52
73	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
74	requests and signal their completion. You don't need thread support	54	requests and signal their completion. You don't need thread support
75	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
…		…
85	yourself, always call C<poll_cb> from within the same thread, or never	65	yourself, always call C<poll_cb> from within the same thread, or never
86	call C<poll_cb> (or other C<aio_> functions) recursively.	66	call C<poll_cb> (or other C<aio_> functions) recursively.
87		67
88	=head2 EXAMPLE	68	=head2 EXAMPLE
89		69
90	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
91	F</etc/passwd> asynchronously:	71	F</etc/passwd> asynchronously:
92		72
93	use Fcntl;	73	use Fcntl;
94	use Event;	74	use EV;
95	use IO::AIO;	75	use IO::AIO;
96		76
97	# register the IO::AIO callback with Event	77	# register the IO::AIO callback with EV
98	Event->io (fd => IO::AIO::poll_fileno,	78	my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
99	poll => 'r',
100	cb => \&IO::AIO::poll_cb);
101		79
102	# queue the request to open /etc/passwd	80	# queue the request to open /etc/passwd
103	aio_open "/etc/passwd", O_RDONLY, 0, sub {	81	aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub {
104	my $fh = shift	82	my $fh = shift
105	or die "error while opening: $!";	83	or die "error while opening: $!";
106		84
107	# stat'ing filehandles is generally non-blocking	85	# stat'ing filehandles is generally non-blocking
108	my $size = -s $fh;	86	my $size = -s $fh;
…		…
117		95
118	# file contents now in $contents	96	# file contents now in $contents
119	print $contents;	97	print $contents;
120		98
121	# exit event loop and program	99	# exit event loop and program
122	Event::unloop;	100	EV::unloop;
123	};	101	};
124	};	102	};
125		103
126	# possibly queue up other requests, or open GUI windows,	104	# possibly queue up other requests, or open GUI windows,
127	# check for sockets etc. etc.	105	# check for sockets etc. etc.
128		106
129	# process events as long as there are some:	107	# process events as long as there are some:
130	Event::loop;	108	EV::loop;
131		109
132	=head1 REQUEST ANATOMY AND LIFETIME	110	=head1 REQUEST ANATOMY AND LIFETIME
133		111
134	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
135	directly visible to Perl.	113	directly visible to Perl.
…		…
183		161
184	=cut	162	=cut
185		163
186	package IO::AIO;	164	package IO::AIO;
187		165
188	no warnings;	166	use Carp ();
189	use strict 'vars';	167
		168	use common::sense;
190		169
191	use base 'Exporter';	170	use base 'Exporter';
192		171
193	BEGIN {	172	BEGIN {
194	our $VERSION = '2.41';	173	our $VERSION = '3.65';
195		174
196	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
197	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
198	aio_readlink aio_fsync aio_fdatasync aio_readahead aio_rename aio_link	177	aio_scandir aio_symlink aio_readlink aio_sync aio_fsync
		178	aio_fdatasync aio_sync_file_range aio_pathsync aio_readahead
		179	aio_rename aio_link aio_move aio_copy aio_group
199	aio_move aio_copy aio_group aio_nop aio_mknod aio_load aio_rmtree aio_mkdir	180	aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown
200	aio_chown aio_chmod aio_utime aio_truncate);	181	aio_chmod aio_utime aio_truncate
		182	aio_msync aio_mtouch aio_mlock aio_mlockall
		183	aio_statvfs);
		184
201	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice aio_block));	185	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));
202	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush	186	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush
203	min_parallel max_parallel max_idle	187	min_parallel max_parallel max_idle
204	nreqs nready npending nthreads	188	nreqs nready npending nthreads
205	max_poll_time max_poll_reqs);	189	max_poll_time max_poll_reqs
		190	sendfile fadvise madvise
		191	mmap munmap munlock munlockall);
		192
		193	push @AIO_REQ, qw(aio_busy); # not exported
206		194
207	@IO::AIO::GRP::ISA = 'IO::AIO::REQ';	195	@IO::AIO::GRP::ISA = 'IO::AIO::REQ';
208		196
209	require XSLoader;	197	require XSLoader;
210	XSLoader::load ("IO::AIO", $VERSION);	198	XSLoader::load ("IO::AIO", $VERSION);
211	}	199	}
212		200
213	=head1 FUNCTIONS	201	=head1 FUNCTIONS
		202
		203	=head2 QUICK OVERVIEW
		204
		205	This section simply lists the prototypes of the most important functions
		206	for quick reference. See the following sections for function-by-function
		207	documentation.
		208
		209	aio_open $pathname, $flags, $mode, $callback->($fh)
		210	aio_close $fh, $callback->($status)
		211	aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
		212	aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
		213	aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
		214	aio_readahead $fh,$offset,$length, $callback->($retval)
		215	aio_stat $fh_or_path, $callback->($status)
		216	aio_lstat $fh, $callback->($status)
		217	aio_statvfs $fh_or_path, $callback->($statvfs)
		218	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
		219	aio_chown $fh_or_path, $uid, $gid, $callback->($status)
		220	aio_truncate $fh_or_path, $offset, $callback->($status)
		221	aio_chmod $fh_or_path, $mode, $callback->($status)
		222	aio_unlink $pathname, $callback->($status)
		223	aio_mknod $path, $mode, $dev, $callback->($status)
		224	aio_link $srcpath, $dstpath, $callback->($status)
		225	aio_symlink $srcpath, $dstpath, $callback->($status)
		226	aio_readlink $path, $callback->($link)
		227	aio_rename $srcpath, $dstpath, $callback->($status)
		228	aio_mkdir $pathname, $mode, $callback->($status)
		229	aio_rmdir $pathname, $callback->($status)
		230	aio_readdir $pathname, $callback->($entries)
		231	aio_readdirx $pathname, $flags, $callback->($entries, $flags)
		232	IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST
		233	IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN
		234	aio_load $path, $data, $callback->($status)
		235	aio_copy $srcpath, $dstpath, $callback->($status)
		236	aio_move $srcpath, $dstpath, $callback->($status)
		237	aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
		238	aio_rmtree $path, $callback->($status)
		239	aio_sync $callback->($status)
		240	aio_fsync $fh, $callback->($status)
		241	aio_fdatasync $fh, $callback->($status)
		242	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
		243	aio_pathsync $path, $callback->($status)
		244	aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
		245	aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
		246	aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
		247	aio_mlockall $flags, $callback->($status)
		248	aio_group $callback->(...)
		249	aio_nop $callback->()
		250
		251	$prev_pri = aioreq_pri [$pri]
		252	aioreq_nice $pri_adjust
		253
		254	IO::AIO::poll_wait
		255	IO::AIO::poll_cb
		256	IO::AIO::poll
		257	IO::AIO::flush
		258	IO::AIO::max_poll_reqs $nreqs
		259	IO::AIO::max_poll_time $seconds
		260	IO::AIO::min_parallel $nthreads
		261	IO::AIO::max_parallel $nthreads
		262	IO::AIO::max_idle $nthreads
		263	IO::AIO::max_outstanding $maxreqs
		264	IO::AIO::nreqs
		265	IO::AIO::nready
		266	IO::AIO::npending
		267
		268	IO::AIO::sendfile $ofh, $ifh, $offset, $count
		269	IO::AIO::fadvise $fh, $offset, $len, $advice
		270	IO::AIO::munlock $scalar, $offset = 0, $length = undef
		271	IO::AIO::munlockall
214		272
215	=head2 AIO REQUEST FUNCTIONS	273	=head2 AIO REQUEST FUNCTIONS
216		274
217	All the C<aio_*> calls are more or less thin wrappers around the syscall	275	All the C<aio_*> calls are more or less thin wrappers around the syscall
218	with the same name (sans C<aio_>). The arguments are similar or identical,	276	with the same name (sans C<aio_>). The arguments are similar or identical,
219	and they all accept an additional (and optional) C<$callback> argument	277	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	278	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	279	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	280	perl, which usually delivers "false") as its sole argument after the given
223	syscall has been executed asynchronously.	281	syscall has been executed asynchronously.
224		282
225	All functions expecting a filehandle keep a copy of the filehandle	283	All functions expecting a filehandle keep a copy of the filehandle
226	internally until the request has finished.	284	internally until the request has finished.
227		285
…		…
241	your pathnames to the locale (or other) encoding in effect in the user	299	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)	300	environment, d) use Glib::filename_from_unicode on unicode filenames or e)
243	use something else to ensure your scalar has the correct contents.	301	use something else to ensure your scalar has the correct contents.
244		302
245	This works, btw. independent of the internal UTF-8 bit, which IO::AIO	303	This works, btw. independent of the internal UTF-8 bit, which IO::AIO
246	handles correctly wether it is set or not.	304	handles correctly whether it is set or not.
247		305
248	=over 4	306	=over 4
249		307
250	=item $prev_pri = aioreq_pri [$pri]	308	=item $prev_pri = aioreq_pri [$pri]
251		309
…		…
298	by the umask in effect then the request is being executed, so better never	356	by the umask in effect then the request is being executed, so better never
299	change the umask.	357	change the umask.
300		358
301	Example:	359	Example:
302		360
303	aio_open "/etc/passwd", O_RDONLY, 0, sub {	361	aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub {
304	if ($_[0]) {	362	if ($_[0]) {
305	print "open successful, fh is $_[0]\n";	363	print "open successful, fh is $_[0]\n";
306	...	364	...
307	} else {	365	} else {
308	die "open failed: $!\n";	366	die "open failed: $!\n";
…		…
311		369
312		370
313	=item aio_close $fh, $callback->($status)	371	=item aio_close $fh, $callback->($status)
314		372
315	Asynchronously close a file and call the callback with the result	373	Asynchronously close a file and call the callback with the result
316	code. I<WARNING:> although accepted, you should not pass in a perl	374	code.
317	filehandle here, as perl will likely close the file descriptor another
318	time when the filehandle is destroyed. Normally, you can safely call perls
319	C<close> or just let filehandles go out of scope.
320		375
321	This is supposed to be a bug in the API, so that might change. It's	376	Unfortunately, you can't do this to perl. Perl I<insists> very strongly on
322	therefore best to avoid this function.	377	closing the file descriptor associated with the filehandle itself.
323		378
		379	Therefore, C<aio_close> will not close the filehandle - instead it will
		380	use dup2 to overwrite the file descriptor with the write-end of a pipe
		381	(the pipe fd will be created on demand and will be cached).
		382
		383	Or in other words: the file descriptor will be closed, but it will not be
		384	free for reuse until the perl filehandle is closed.
		385
		386	=cut
324		387
325	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	388	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
326		389
327	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	390	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
328		391
329	Reads or writes C<$length> bytes from the specified C<$fh> and C<$offset>	392	Reads or writes C<$length> bytes from or to the specified C<$fh> and
330	into the scalar given by C<$data> and offset C<$dataoffset> and calls the	393	C<$offset> into the scalar given by C<$data> and offset C<$dataoffset>
331	callback without the actual number of bytes read (or -1 on error, just	394	and calls the callback without the actual number of bytes read (or -1 on
332	like the syscall).	395	error, just like the syscall).
		396
		397	C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to
		398	offset plus the actual number of bytes read.
333		399
334	If C<$offset> is undefined, then the current file descriptor offset will	400	If C<$offset> is undefined, then the current file descriptor offset will
335	be used (and updated), otherwise the file descriptor offset will not be	401	be used (and updated), otherwise the file descriptor offset will not be
336	changed by these calls.	402	changed by these calls.
337		403
338	If C<$length> is undefined in C<aio_write>, use the remaining length of C<$data>.	404	If C<$length> is undefined in C<aio_write>, use the remaining length of
		405	C<$data>.
339		406
340	If C<$dataoffset> is less than zero, it will be counted from the end of	407	If C<$dataoffset> is less than zero, it will be counted from the end of
341	C<$data>.	408	C<$data>.
342		409
343	The C<$data> scalar I<MUST NOT> be modified in any way while the request	410	The C<$data> scalar I<MUST NOT> be modified in any way while the request
…		…
361	than one C<aio_sendfile> per C<$out_fh>, as they will interfere with each	428	than one C<aio_sendfile> per C<$out_fh>, as they will interfere with each
362	other.	429	other.
363		430
364	This call tries to make use of a native C<sendfile> syscall to provide	431	This call tries to make use of a native C<sendfile> syscall to provide
365	zero-copy operation. For this to work, C<$out_fh> should refer to a	432	zero-copy operation. For this to work, C<$out_fh> should refer to a
366	socket, and C<$in_fh> should refer to mmap'able file.	433	socket, and C<$in_fh> should refer to an mmap'able file.
367		434
368	If the native sendfile call fails or is not implemented, it will be	435	If a native sendfile cannot be found or it fails with C<ENOSYS>,
		436	C<ENOTSUP>, C<EOPNOTSUPP>, C<EAFNOSUPPORT>, C<EPROTOTYPE> or C<ENOTSOCK>,
369	emulated, so you can call C<aio_sendfile> on any type of filehandle	437	it will be emulated, so you can call C<aio_sendfile> on any type of
370	regardless of the limitations of the operating system.	438	filehandle regardless of the limitations of the operating system.
371		439
372	Please note, however, that C<aio_sendfile> can read more bytes from	440	Please note, however, that C<aio_sendfile> can read more bytes from
373	C<$in_fh> than are written, and there is no way to find out how many	441	C<$in_fh> than are written, and there is no way to find out how many
374	bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only	442	bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only
375	provides the number of bytes written to C<$out_fh>. Only if the result	443	provides the number of bytes written to C<$out_fh>. Only if the result
…		…
413	$_[0] and die "stat failed: $!";	481	$_[0] and die "stat failed: $!";
414	print "size is ", -s _, "\n";	482	print "size is ", -s _, "\n";
415	};	483	};
416		484
417		485
		486	=item aio_statvfs $fh_or_path, $callback->($statvfs)
		487
		488	Works like the POSIX C<statvfs> or C<fstatvfs> syscalls, depending on
		489	whether a file handle or path was passed.
		490
		491	On success, the callback is passed a hash reference with the following
		492	members: C<bsize>, C<frsize>, C<blocks>, C<bfree>, C<bavail>, C<files>,
		493	C<ffree>, C<favail>, C<fsid>, C<flag> and C<namemax>. On failure, C<undef>
		494	is passed.
		495
		496	The following POSIX IO::AIO::ST_* constants are defined: C<ST_RDONLY> and
		497	C<ST_NOSUID>.
		498
		499	The following non-POSIX IO::AIO::ST_* flag masks are defined to
		500	their correct value when available, or to C<0> on systems that do
		501	not support them: C<ST_NODEV>, C<ST_NOEXEC>, C<ST_SYNCHRONOUS>,
		502	C<ST_MANDLOCK>, C<ST_WRITE>, C<ST_APPEND>, C<ST_IMMUTABLE>, C<ST_NOATIME>,
		503	C<ST_NODIRATIME> and C<ST_RELATIME>.
		504
		505	Example: stat C</wd> and dump out the data if successful.
		506
		507	aio_statvfs "/wd", sub {
		508	my $f = $_[0]
		509	or die "statvfs: $!";
		510
		511	use Data::Dumper;
		512	say Dumper $f;
		513	};
		514
		515	# result:
		516	{
		517	bsize => 1024,
		518	bfree => 4333064312,
		519	blocks => 10253828096,
		520	files => 2050765568,
		521	flag => 4096,
		522	favail => 2042092649,
		523	bavail => 4333064312,
		524	ffree => 2042092649,
		525	namemax => 255,
		526	frsize => 1024,
		527	fsid => 1810
		528	}
		529
		530
418	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	531	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
419		532
420	Works like perl's C<utime> function (including the special case of $atime	533	Works like perl's C<utime> function (including the special case of $atime
421	and $mtime being undef). Fractional times are supported if the underlying	534	and $mtime being undef). Fractional times are supported if the underlying
422	syscalls support them.	535	syscalls support them.
…		…
515		628
516	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire	629	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire
517	directory (i.e. opendir + readdir + closedir). The entries will not be	630	directory (i.e. opendir + readdir + closedir). The entries will not be
518	sorted, and will B<NOT> include the C<.> and C<..> entries.	631	sorted, and will B<NOT> include the C<.> and C<..> entries.
519		632
520	The callback a single argument which is either C<undef> or an array-ref	633	The callback is passed a single argument which is either C<undef> or an
521	with the filenames.	634	array-ref with the filenames.
		635
		636
		637	=item aio_readdirx $pathname, $flags, $callback->($entries, $flags)
		638
		639	Quite similar to C<aio_readdir>, but the C<$flags> argument allows to tune
		640	behaviour and output format. In case of an error, C<$entries> will be
		641	C<undef>.
		642
		643	The flags are a combination of the following constants, ORed together (the
		644	flags will also be passed to the callback, possibly modified):
		645
		646	=over 4
		647
		648	=item IO::AIO::READDIR_DENTS
		649
		650	When this flag is off, then the callback gets an arrayref with of names
		651	only (as with C<aio_readdir>), otherwise it gets an arrayref with
		652	C<[$name, $type, $inode]> arrayrefs, each describing a single directory
		653	entry in more detail.
		654
		655	C<$name> is the name of the entry.
		656
		657	C<$type> is one of the C<IO::AIO::DT_xxx> constants:
		658
		659	C<IO::AIO::DT_UNKNOWN>, C<IO::AIO::DT_FIFO>, C<IO::AIO::DT_CHR>, C<IO::AIO::DT_DIR>,
		660	C<IO::AIO::DT_BLK>, C<IO::AIO::DT_REG>, C<IO::AIO::DT_LNK>, C<IO::AIO::DT_SOCK>,
		661	C<IO::AIO::DT_WHT>.
		662
		663	C<IO::AIO::DT_UNKNOWN> means just that: readdir does not know. If you need to
		664	know, you have to run stat yourself. Also, for speed reasons, the C<$type>
		665	scalars are read-only: you can not modify them.
		666
		667	C<$inode> is the inode number (which might not be exact on systems with 64
		668	bit inode numbers and 32 bit perls). This field has unspecified content on
		669	systems that do not deliver the inode information.
		670
		671	=item IO::AIO::READDIR_DIRS_FIRST
		672
		673	When this flag is set, then the names will be returned in an order where
		674	likely directories come first. This is useful when you need to quickly
		675	find directories, or you want to find all directories while avoiding to
		676	stat() each entry.
		677
		678	If the system returns type information in readdir, then this is used
		679	to find directories directly. Otherwise, likely directories are files
		680	beginning with ".", or otherwise files with no dots, of which files with
		681	short names are tried first.
		682
		683	=item IO::AIO::READDIR_STAT_ORDER
		684
		685	When this flag is set, then the names will be returned in an order
		686	suitable for stat()'ing each one. That is, when you plan to stat()
		687	all files in the given directory, then the returned order will likely
		688	be fastest.
		689
		690	If both this flag and C<IO::AIO::READDIR_DIRS_FIRST> are specified, then
		691	the likely dirs come first, resulting in a less optimal stat order.
		692
		693	=item IO::AIO::READDIR_FOUND_UNKNOWN
		694
		695	This flag should not be set when calling C<aio_readdirx>. Instead, it
		696	is being set by C<aio_readdirx>, when any of the C<$type>'s found were
		697	C<IO::AIO::DT_UNKNOWN>. The absense of this flag therefore indicates that all
		698	C<$type>'s are known, which can be used to speed up some algorithms.
		699
		700	=back
522		701
523		702
524	=item aio_load $path, $data, $callback->($status)	703	=item aio_load $path, $data, $callback->($status)
525		704
526	This is a composite request that tries to fully load the given file into	705	This is a composite request that tries to fully load the given file into
527	memory. Status is the same as with aio_read.	706	memory. Status is the same as with aio_read.
528		707
529	=cut	708	=cut
530		709
531	sub aio_load($$;$) {	710	sub aio_load($$;$) {
532	aio_block {
533	my ($path, undef, $cb) = @_;	711	my ($path, undef, $cb) = @_;
534	my $data = \$_[1];	712	my $data = \$_[1];
535		713
536	my $pri = aioreq_pri;	714	my $pri = aioreq_pri;
537	my $grp = aio_group $cb;	715	my $grp = aio_group $cb;
		716
		717	aioreq_pri $pri;
		718	add $grp aio_open $path, O_RDONLY, 0, sub {
		719	my $fh = shift
		720	or return $grp->result (-1);
538		721
539	aioreq_pri $pri;	722	aioreq_pri $pri;
540	add $grp aio_open $path, O_RDONLY, 0, sub {
541	my $fh = shift
542	or return $grp->result (-1);
543
544	aioreq_pri $pri;
545	add $grp aio_read $fh, 0, (-s $fh), $$data, 0, sub {	723	add $grp aio_read $fh, 0, (-s $fh), $$data, 0, sub {
546	$grp->result ($_[0]);	724	$grp->result ($_[0]);
547	};
548	};	725	};
549
550	$grp
551	}	726	};
		727
		728	$grp
552	}	729	}
553		730
554	=item aio_copy $srcpath, $dstpath, $callback->($status)	731	=item aio_copy $srcpath, $dstpath, $callback->($status)
555		732
556	Try to copy the I<file> (directories not supported as either source or	733	Try to copy the I<file> (directories not supported as either source or
557	destination) from C<$srcpath> to C<$dstpath> and call the callback with	734	destination) from C<$srcpath> to C<$dstpath> and call the callback with
558	the C<0> (error) or C<-1> ok.	735	a status of C<0> (ok) or C<-1> (error, see C<$!>).
559		736
560	This is a composite request that it creates the destination file with	737	This is a composite request that creates the destination file with
561	mode 0200 and copies the contents of the source file into it using	738	mode 0200 and copies the contents of the source file into it using
562	C<aio_sendfile>, followed by restoring atime, mtime, access mode and	739	C<aio_sendfile>, followed by restoring atime, mtime, access mode and
563	uid/gid, in that order.	740	uid/gid, in that order.
564		741
565	If an error occurs, the partial destination file will be unlinked, if	742	If an error occurs, the partial destination file will be unlinked, if
…		…
567	errors are being ignored.	744	errors are being ignored.
568		745
569	=cut	746	=cut
570		747
571	sub aio_copy($$;$) {	748	sub aio_copy($$;$) {
572	aio_block {
573	my ($src, $dst, $cb) = @_;	749	my ($src, $dst, $cb) = @_;
574		750
575	my $pri = aioreq_pri;	751	my $pri = aioreq_pri;
576	my $grp = aio_group $cb;	752	my $grp = aio_group $cb;
577		753
578	aioreq_pri $pri;	754	aioreq_pri $pri;
579	add $grp aio_open $src, O_RDONLY, 0, sub {	755	add $grp aio_open $src, O_RDONLY, 0, sub {
580	if (my $src_fh = $_[0]) {	756	if (my $src_fh = $_[0]) {
581	my @stat = stat $src_fh;	757	my @stat = stat $src_fh; # hmm, might block over nfs?
582		758
583	aioreq_pri $pri;	759	aioreq_pri $pri;
584	add $grp aio_open $dst, O_CREAT \| O_WRONLY \| O_TRUNC, 0200, sub {	760	add $grp aio_open $dst, O_CREAT \| O_WRONLY \| O_TRUNC, 0200, sub {
585	if (my $dst_fh = $_[0]) {	761	if (my $dst_fh = $_[0]) {
586	aioreq_pri $pri;	762	aioreq_pri $pri;
587	add $grp aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub {	763	add $grp aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub {
588	if ($_[0] == $stat[7]) {	764	if ($_[0] == $stat[7]) {
589	$grp->result (0);	765	$grp->result (0);
590	close $src_fh;	766	close $src_fh;
591		767
592	# those should not normally block. should. should.
593	utime $stat[8], $stat[9], $dst;
594	chmod $stat[2] & 07777, $dst_fh;
595	chown $stat[4], $stat[5], $dst_fh;
596	close $dst_fh;
597	} else {	768	my $ch = sub {
598	$grp->result (-1);
599	close $src_fh;
600	close $dst_fh;
601
602	aioreq $pri;	769	aioreq_pri $pri;
		770	add $grp aio_chmod $dst_fh, $stat[2] & 07777, sub {
		771	aioreq_pri $pri;
		772	add $grp aio_chown $dst_fh, $stat[4], $stat[5], sub {
		773	aioreq_pri $pri;
603	add $grp aio_unlink $dst;	774	add $grp aio_close $dst_fh;
		775	}
		776	};
604	}	777	};
		778
		779	aioreq_pri $pri;
		780	add $grp aio_utime $dst_fh, $stat[8], $stat[9], sub {
		781	if ($_[0] < 0 && $! == ENOSYS) {
		782	aioreq_pri $pri;
		783	add $grp aio_utime $dst, $stat[8], $stat[9], $ch;
		784	} else {
		785	$ch->();
		786	}
		787	};
		788	} else {
		789	$grp->result (-1);
		790	close $src_fh;
		791	close $dst_fh;
		792
		793	aioreq $pri;
		794	add $grp aio_unlink $dst;
605	};	795	}
606	} else {
607	$grp->result (-1);
608	}	796	};
		797	} else {
		798	$grp->result (-1);
609	},	799	}
610
611	} else {
612	$grp->result (-1);
613	}	800	},
		801
		802	} else {
		803	$grp->result (-1);
614	};	804	}
615
616	$grp
617	}	805	};
		806
		807	$grp
618	}	808	}
619		809
620	=item aio_move $srcpath, $dstpath, $callback->($status)	810	=item aio_move $srcpath, $dstpath, $callback->($status)
621		811
622	Try to move the I<file> (directories not supported as either source or	812	Try to move the I<file> (directories not supported as either source or
623	destination) from C<$srcpath> to C<$dstpath> and call the callback with	813	destination) from C<$srcpath> to C<$dstpath> and call the callback with
624	the C<0> (error) or C<-1> ok.	814	a status of C<0> (ok) or C<-1> (error, see C<$!>).
625		815
626	This is a composite request that tries to rename(2) the file first. If	816	This is a composite request that tries to rename(2) the file first; if
627	rename files with C<EXDEV>, it copies the file with C<aio_copy> and, if	817	rename fails with C<EXDEV>, it copies the file with C<aio_copy> and, if
628	that is successful, unlinking the C<$srcpath>.	818	that is successful, unlinks the C<$srcpath>.
629		819
630	=cut	820	=cut
631		821
632	sub aio_move($$;$) {	822	sub aio_move($$;$) {
633	aio_block {
634	my ($src, $dst, $cb) = @_;	823	my ($src, $dst, $cb) = @_;
635		824
636	my $pri = aioreq_pri;	825	my $pri = aioreq_pri;
637	my $grp = aio_group $cb;	826	my $grp = aio_group $cb;
638		827
639	aioreq_pri $pri;	828	aioreq_pri $pri;
640	add $grp aio_rename $src, $dst, sub {	829	add $grp aio_rename $src, $dst, sub {
641	if ($_[0] && $! == EXDEV) {	830	if ($_[0] && $! == EXDEV) {
642	aioreq_pri $pri;	831	aioreq_pri $pri;
643	add $grp aio_copy $src, $dst, sub {	832	add $grp aio_copy $src, $dst, sub {
644	$grp->result ($_[0]);
645
646	if (!$_[0]) {
647	aioreq_pri $pri;
648	add $grp aio_unlink $src;
649	}
650	};
651	} else {
652	$grp->result ($_[0]);	833	$grp->result ($_[0]);
		834
		835	if (!$_[0]) {
		836	aioreq_pri $pri;
		837	add $grp aio_unlink $src;
		838	}
653	}	839	};
		840	} else {
		841	$grp->result ($_[0]);
654	};	842	}
655
656	$grp
657	}	843	};
		844
		845	$grp
658	}	846	}
659		847
660	=item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)	848	=item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
661		849
662	Scans a directory (similar to C<aio_readdir>) but additionally tries to	850	Scans a directory (similar to C<aio_readdir>) but additionally tries to
…		…
682		870
683	Implementation notes.	871	Implementation notes.
684		872
685	The C<aio_readdir> cannot be avoided, but C<stat()>'ing every entry can.	873	The C<aio_readdir> cannot be avoided, but C<stat()>'ing every entry can.
686		874
		875	If readdir returns file type information, then this is used directly to
		876	find directories.
		877
687	After reading the directory, the modification time, size etc. of the	878	Otherwise, after reading the directory, the modification time, size etc.
688	directory before and after the readdir is checked, and if they match (and	879	of the directory before and after the readdir is checked, and if they
689	isn't the current time), the link count will be used to decide how many	880	match (and isn't the current time), the link count will be used to decide
690	entries are directories (if >= 2). Otherwise, no knowledge of the number	881	how many entries are directories (if >= 2). Otherwise, no knowledge of the
691	of subdirectories will be assumed.	882	number of subdirectories will be assumed.
692		883
693	Then entries will be sorted into likely directories (everything without	884	Then entries will be sorted into likely directories a non-initial dot
694	a non-initial dot currently) and likely non-directories (everything	885	currently) and likely non-directories (see C<aio_readdirx>). Then every
695	else). Then every entry plus an appended C</.> will be C<stat>'ed,	886	entry plus an appended C</.> will be C<stat>'ed, likely directories first,
696	likely directories first. If that succeeds, it assumes that the entry	887	in order of their inode numbers. If that succeeds, it assumes that the
697	is a directory or a symlink to directory (which will be checked	888	entry is a directory or a symlink to directory (which will be checked
698	seperately). This is often faster than stat'ing the entry itself because	889	seperately). This is often faster than stat'ing the entry itself because
699	filesystems might detect the type of the entry without reading the inode	890	filesystems might detect the type of the entry without reading the inode
700	data (e.g. ext2fs filetype feature).	891	data (e.g. ext2fs filetype feature), even on systems that cannot return
		892	the filetype information on readdir.
701		893
702	If the known number of directories (link count - 2) has been reached, the	894	If the known number of directories (link count - 2) has been reached, the
703	rest of the entries is assumed to be non-directories.	895	rest of the entries is assumed to be non-directories.
704		896
705	This only works with certainty on POSIX (= UNIX) filesystems, which	897	This only works with certainty on POSIX (= UNIX) filesystems, which
…		…
710	directory counting heuristic.	902	directory counting heuristic.
711		903
712	=cut	904	=cut
713		905
714	sub aio_scandir($$;$) {	906	sub aio_scandir($$;$) {
715	aio_block {
716	my ($path, $maxreq, $cb) = @_;	907	my ($path, $maxreq, $cb) = @_;
717		908
718	my $pri = aioreq_pri;	909	my $pri = aioreq_pri;
719		910
720	my $grp = aio_group $cb;	911	my $grp = aio_group $cb;
721		912
722	$maxreq = 4 if $maxreq <= 0;	913	$maxreq = 4 if $maxreq <= 0;
723		914
724	# stat once	915	# stat once
		916	aioreq_pri $pri;
		917	add $grp aio_stat $path, sub {
		918	return $grp->result () if $_[0];
		919	my $now = time;
		920	my $hash1 = join ":", (stat _)[0,1,3,7,9];
		921
		922	# read the directory entries
725	aioreq_pri $pri;	923	aioreq_pri $pri;
726	add $grp aio_stat $path, sub {	924	add $grp aio_readdirx $path, READDIR_DIRS_FIRST, sub {
		925	my $entries = shift
727	return $grp->result () if $_[0];	926	or return $grp->result ();
728	my $now = time;
729	my $hash1 = join ":", (stat _)[0,1,3,7,9];
730		927
731	# read the directory entries	928	# stat the dir another time
732	aioreq_pri $pri;	929	aioreq_pri $pri;
733	add $grp aio_readdir $path, sub {
734	my $entries = shift
735	or return $grp->result ();
736
737	# stat the dir another time
738	aioreq_pri $pri;
739	add $grp aio_stat $path, sub {	930	add $grp aio_stat $path, sub {
740	my $hash2 = join ":", (stat _)[0,1,3,7,9];	931	my $hash2 = join ":", (stat _)[0,1,3,7,9];
741		932
742	my $ndirs;	933	my $ndirs;
743		934
744	# take the slow route if anything looks fishy	935	# take the slow route if anything looks fishy
745	if ($hash1 ne $hash2 or (stat _)[9] == $now) {	936	if ($hash1 ne $hash2 or (stat _)[9] == $now) {
746	$ndirs = -1;	937	$ndirs = -1;
747	} else {	938	} else {
748	# if nlink == 2, we are finished	939	# if nlink == 2, we are finished
749	# on non-posix-fs's, we rely on nlink < 2	940	# for non-posix-fs's, we rely on nlink < 2
750	$ndirs = (stat _)[3] - 2	941	$ndirs = (stat _)[3] - 2
751	or return $grp->result ([], $entries);	942	or return $grp->result ([], $entries);
752	}	943	}
753		944
754	# sort into likely dirs and likely nondirs
755	# dirs == files without ".", short entries first
756	$entries = [map $_->[0],
757	sort { $b->[1] cmp $a->[1] }
758	map [$_, sprintf "%s%04d", (/.\./ ? "1" : "0"), length],
759	@$entries];
760
761	my (@dirs, @nondirs);	945	my (@dirs, @nondirs);
762		946
763	my $statgrp = add $grp aio_group sub {	947	my $statgrp = add $grp aio_group sub {
764	$grp->result (\@dirs, \@nondirs);	948	$grp->result (\@dirs, \@nondirs);
765	};	949	};
766		950
767	limit $statgrp $maxreq;	951	limit $statgrp $maxreq;
768	feed $statgrp sub {	952	feed $statgrp sub {
769	return unless @$entries;	953	return unless @$entries;
770	my $entry = pop @$entries;	954	my $entry = shift @$entries;
771		955
772	aioreq_pri $pri;	956	aioreq_pri $pri;
773	add $statgrp aio_stat "$path/$entry/.", sub {	957	add $statgrp aio_stat "$path/$entry/.", sub {
774	if ($_[0] < 0) {	958	if ($_[0] < 0) {
775	push @nondirs, $entry;	959	push @nondirs, $entry;
776	} else {	960	} else {
777	# need to check for real directory	961	# need to check for real directory
778	aioreq_pri $pri;	962	aioreq_pri $pri;
779	add $statgrp aio_lstat "$path/$entry", sub {	963	add $statgrp aio_lstat "$path/$entry", sub {
780	if (-d _) {	964	if (-d _) {
781	push @dirs, $entry;	965	push @dirs, $entry;
782		966
783	unless (--$ndirs) {	967	unless (--$ndirs) {
784	push @nondirs, @$entries;	968	push @nondirs, @$entries;
785	feed $statgrp;	969	feed $statgrp;
786	}
787	} else {
788	push @nondirs, $entry;
789	}	970	}
		971	} else {
		972	push @nondirs, $entry;
790	}	973	}
791	}	974	}
792	};	975	}
793	};	976	};
794	};	977	};
795	};	978	};
796	};	979	};
797
798	$grp
799	}	980	};
		981
		982	$grp
800	}	983	}
801		984
802	=item aio_rmtree $path, $callback->($status)	985	=item aio_rmtree $path, $callback->($status)
803		986
804	Delete a directory tree starting (and including) C<$path>, return the	987	Delete a directory tree starting (and including) C<$path>, return the
…		…
808		991
809	=cut	992	=cut
810		993
811	sub aio_rmtree;	994	sub aio_rmtree;
812	sub aio_rmtree($;$) {	995	sub aio_rmtree($;$) {
813	aio_block {
814	my ($path, $cb) = @_;	996	my ($path, $cb) = @_;
815		997
816	my $pri = aioreq_pri;	998	my $pri = aioreq_pri;
817	my $grp = aio_group $cb;	999	my $grp = aio_group $cb;
818		1000
819	aioreq_pri $pri;	1001	aioreq_pri $pri;
820	add $grp aio_scandir $path, 0, sub {	1002	add $grp aio_scandir $path, 0, sub {
821	my ($dirs, $nondirs) = @_;	1003	my ($dirs, $nondirs) = @_;
822		1004
823	my $dirgrp = aio_group sub {	1005	my $dirgrp = aio_group sub {
824	add $grp aio_rmdir $path, sub {	1006	add $grp aio_rmdir $path, sub {
825	$grp->result ($_[0]);	1007	$grp->result ($_[0]);
826	};
827	};	1008	};
828
829	(aioreq_pri $pri), add $dirgrp aio_rmtree "$path/$_" for @$dirs;
830	(aioreq_pri $pri), add $dirgrp aio_unlink "$path/$_" for @$nondirs;
831
832	add $grp $dirgrp;
833	};	1009	};
834		1010
835	$grp	1011	(aioreq_pri $pri), add $dirgrp aio_rmtree "$path/$_" for @$dirs;
		1012	(aioreq_pri $pri), add $dirgrp aio_unlink "$path/$_" for @$nondirs;
		1013
		1014	add $grp $dirgrp;
836	}	1015	};
		1016
		1017	$grp
837	}	1018	}
		1019
		1020	=item aio_sync $callback->($status)
		1021
		1022	Asynchronously call sync and call the callback when finished.
838		1023
839	=item aio_fsync $fh, $callback->($status)	1024	=item aio_fsync $fh, $callback->($status)
840		1025
841	Asynchronously call fsync on the given filehandle and call the callback	1026	Asynchronously call fsync on the given filehandle and call the callback
842	with the fsync result code.	1027	with the fsync result code.
…		…
846	Asynchronously call fdatasync on the given filehandle and call the	1031	Asynchronously call fdatasync on the given filehandle and call the
847	callback with the fdatasync result code.	1032	callback with the fdatasync result code.
848		1033
849	If this call isn't available because your OS lacks it or it couldn't be	1034	If this call isn't available because your OS lacks it or it couldn't be
850	detected, it will be emulated by calling C<fsync> instead.	1035	detected, it will be emulated by calling C<fsync> instead.
		1036
		1037	=item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
		1038
		1039	Sync the data portion of the file specified by C<$offset> and C<$length>
		1040	to disk (but NOT the metadata), by calling the Linux-specific
		1041	sync_file_range call. If sync_file_range is not available or it returns
		1042	ENOSYS, then fdatasync or fsync is being substituted.
		1043
		1044	C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>,
		1045	C<IO::AIO::SYNC_FILE_RANGE_WRITE> and
		1046	C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range
		1047	manpage for details.
		1048
		1049	=item aio_pathsync $path, $callback->($status)
		1050
		1051	This request tries to open, fsync and close the given path. This is a
		1052	composite request intended to sync directories after directory operations
		1053	(E.g. rename). This might not work on all operating systems or have any
		1054	specific effect, but usually it makes sure that directory changes get
		1055	written to disc. It works for anything that can be opened for read-only,
		1056	not just directories.
		1057
		1058	Future versions of this function might fall back to other methods when
		1059	C<fsync> on the directory fails (such as calling C<sync>).
		1060
		1061	Passes C<0> when everything went ok, and C<-1> on error.
		1062
		1063	=cut
		1064
		1065	sub aio_pathsync($;$) {
		1066	my ($path, $cb) = @_;
		1067
		1068	my $pri = aioreq_pri;
		1069	my $grp = aio_group $cb;
		1070
		1071	aioreq_pri $pri;
		1072	add $grp aio_open $path, O_RDONLY, 0, sub {
		1073	my ($fh) = @_;
		1074	if ($fh) {
		1075	aioreq_pri $pri;
		1076	add $grp aio_fsync $fh, sub {
		1077	$grp->result ($_[0]);
		1078
		1079	aioreq_pri $pri;
		1080	add $grp aio_close $fh;
		1081	};
		1082	} else {
		1083	$grp->result (-1);
		1084	}
		1085	};
		1086
		1087	$grp
		1088	}
		1089
		1090	=item aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
		1091
		1092	This is a rather advanced IO::AIO call, which only works on mmap(2)ed
		1093	scalars (see the C<IO::AIO::mmap> function, although it also works on data
		1094	scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the
		1095	scalar must only be modified in-place while an aio operation is pending on
		1096	it).
		1097
		1098	It calls the C<msync> function of your OS, if available, with the memory
		1099	area starting at C<$offset> in the string and ending C<$length> bytes
		1100	later. If C<$length> is negative, counts from the end, and if C<$length>
		1101	is C<undef>, then it goes till the end of the string. The flags can be
		1102	a combination of C<IO::AIO::MS_ASYNC>, C<IO::AIO::MS_INVALIDATE> and
		1103	C<IO::AIO::MS_SYNC>.
		1104
		1105	=item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
		1106
		1107	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
		1108	scalars.
		1109
		1110	It touches (reads or writes) all memory pages in the specified
		1111	range inside the scalar. All caveats and parameters are the same
		1112	as for C<aio_msync>, above, except for flags, which must be either
		1113	C<0> (which reads all pages and ensures they are instantiated) or
		1114	C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and
		1115	writing an octet from it, which dirties the page).
		1116
		1117	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
		1118
		1119	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
		1120	scalars.
		1121
		1122	It reads in all the pages of the underlying storage into memory (if any)
		1123	and locks them, so they are not getting swapped/paged out or removed.
		1124
		1125	If C<$length> is undefined, then the scalar will be locked till the end.
		1126
		1127	On systems that do not implement C<mlock>, this function returns C<-1>
		1128	and sets errno to C<ENOSYS>.
		1129
		1130	Note that the corresponding C<munlock> is synchronous and is
		1131	documented under L<MISCELLANEOUS FUNCTIONS>.
		1132
		1133	=item aio_mlockall $flags, $callback->($status)
		1134
		1135	Calls the C<mlockall> function with the given C<$flags> (a combination of
		1136	C<IO::AIO::MCL_CURRENT> and C<IO::AIO::MCL_FUTURE>).
		1137
		1138	On systems that do not implement C<mlockall>, this function returns C<-1>
		1139	and sets errno to C<ENOSYS>.
		1140
		1141	Note that the corresponding C<munlockall> is synchronous and is
		1142	documented under L<MISCELLANEOUS FUNCTIONS>.
851		1143
852	=item aio_group $callback->(...)	1144	=item aio_group $callback->(...)
853		1145
854	This is a very special aio request: Instead of doing something, it is a	1146	This is a very special aio request: Instead of doing something, it is a
855	container for other aio requests, which is useful if you want to bundle	1147	container for other aio requests, which is useful if you want to bundle
…		…
905	=item cancel $req	1197	=item cancel $req
906		1198
907	Cancels the request, if possible. Has the effect of skipping execution	1199	Cancels the request, if possible. Has the effect of skipping execution
908	when entering the B<execute> state and skipping calling the callback when	1200	when entering the B<execute> state and skipping calling the callback when
909	entering the the B<result> state, but will leave the request otherwise	1201	entering the the B<result> state, but will leave the request otherwise
910	untouched. That means that requests that currently execute will not be	1202	untouched (with the exception of readdir). That means that requests that
911	stopped and resources held by the request will not be freed prematurely.	1203	currently execute will not be stopped and resources held by the request
		1204	will not be freed prematurely.
912		1205
913	=item cb $req $callback->(...)	1206	=item cb $req $callback->(...)
914		1207
915	Replace (or simply set) the callback registered to the request.	1208	Replace (or simply set) the callback registered to the request.
916		1209
…		…
967	Their lifetime, simplified, looks like this: when they are empty, they	1260	Their lifetime, simplified, looks like this: when they are empty, they
968	will finish very quickly. If they contain only requests that are in the	1261	will finish very quickly. If they contain only requests that are in the
969	C<done> state, they will also finish. Otherwise they will continue to	1262	C<done> state, they will also finish. Otherwise they will continue to
970	exist.	1263	exist.
971		1264
972	That means after creating a group you have some time to add requests. And	1265	That means after creating a group you have some time to add requests
973	in the callbacks of those requests, you can add further requests to the	1266	(precisely before the callback has been invoked, which is only done within
974	group. And only when all those requests have finished will the the group	1267	the C<poll_cb>). And in the callbacks of those requests, you can add
975	itself finish.	1268	further requests to the group. And only when all those requests have
		1269	finished will the the group itself finish.
976		1270
977	=over 4	1271	=over 4
978		1272
979	=item add $grp ...	1273	=item add $grp ...
980		1274
…		…
989	=item $grp->cancel_subs	1283	=item $grp->cancel_subs
990		1284
991	Cancel all subrequests and clears any feeder, but not the group request	1285	Cancel all subrequests and clears any feeder, but not the group request
992	itself. Useful when you queued a lot of events but got a result early.	1286	itself. Useful when you queued a lot of events but got a result early.
993		1287
		1288	The group request will finish normally (you cannot add requests to the
		1289	group).
		1290
994	=item $grp->result (...)	1291	=item $grp->result (...)
995		1292
996	Set the result value(s) that will be passed to the group callback when all	1293	Set the result value(s) that will be passed to the group callback when all
997	subrequests have finished and set thre groups errno to the current value	1294	subrequests have finished and set the groups errno to the current value
998	of errno (just like calling C<errno> without an error number). By default,	1295	of errno (just like calling C<errno> without an error number). By default,
999	no argument will be passed and errno is zero.	1296	no argument will be passed and errno is zero.
1000		1297
1001	=item $grp->errno ([$errno])	1298	=item $grp->errno ([$errno])
1002		1299
…		…
1013	=item feed $grp $callback->($grp)	1310	=item feed $grp $callback->($grp)
1014		1311
1015	Sets a feeder/generator on this group: every group can have an attached	1312	Sets a feeder/generator on this group: every group can have an attached
1016	generator that generates requests if idle. The idea behind this is that,	1313	generator that generates requests if idle. The idea behind this is that,
1017	although you could just queue as many requests as you want in a group,	1314	although you could just queue as many requests as you want in a group,
1018	this might starve other requests for a potentially long time. For	1315	this might starve other requests for a potentially long time. For example,
1019	example, C<aio_scandir> might generate hundreds of thousands C<aio_stat>	1316	C<aio_scandir> might generate hundreds of thousands C<aio_stat> requests,
1020	requests, delaying any later requests for a long time.	1317	delaying any later requests for a long time.
1021		1318
1022	To avoid this, and allow incremental generation of requests, you can	1319	To avoid this, and allow incremental generation of requests, you can
1023	instead a group and set a feeder on it that generates those requests. The	1320	instead a group and set a feeder on it that generates those requests. The
1024	feed callback will be called whenever there are few enough (see C<limit>,	1321	feed callback will be called whenever there are few enough (see C<limit>,
1025	below) requests active in the group itself and is expected to queue more	1322	below) requests active in the group itself and is expected to queue more
…		…
1029	not impose any limits).	1326	not impose any limits).
1030		1327
1031	If the feed does not queue more requests when called, it will be	1328	If the feed does not queue more requests when called, it will be
1032	automatically removed from the group.	1329	automatically removed from the group.
1033		1330
1034	If the feed limit is C<0>, it will be set to C<2> automatically.	1331	If the feed limit is C<0> when this method is called, it will be set to
		1332	C<2> automatically.
1035		1333
1036	Example:	1334	Example:
1037		1335
1038	# stat all files in @files, but only ever use four aio requests concurrently:	1336	# stat all files in @files, but only ever use four aio requests concurrently:
1039		1337
…		…
1051	Sets the feeder limit for the group: The feeder will be called whenever	1349	Sets the feeder limit for the group: The feeder will be called whenever
1052	the group contains less than this many requests.	1350	the group contains less than this many requests.
1053		1351
1054	Setting the limit to C<0> will pause the feeding process.	1352	Setting the limit to C<0> will pause the feeding process.
1055		1353
		1354	The default value for the limit is C<0>, but note that setting a feeder
		1355	automatically bumps it up to C<2>.
		1356
1056	=back	1357	=back
1057		1358
1058	=head2 SUPPORT FUNCTIONS	1359	=head2 SUPPORT FUNCTIONS
1059		1360
1060	=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION	1361	=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION
…		…
1062	=over 4	1363	=over 4
1063		1364
1064	=item $fileno = IO::AIO::poll_fileno	1365	=item $fileno = IO::AIO::poll_fileno
1065		1366
1066	Return the I<request result pipe file descriptor>. This filehandle must be	1367	Return the I<request result pipe file descriptor>. This filehandle must be
1067	polled for reading by some mechanism outside this module (e.g. Event or	1368	polled for reading by some mechanism outside this module (e.g. EV, Glib,
1068	select, see below or the SYNOPSIS). If the pipe becomes readable you have	1369	select and so on, see below or the SYNOPSIS). If the pipe becomes readable
1069	to call C<poll_cb> to check the results.	1370	you have to call C<poll_cb> to check the results.
1070		1371
1071	See C<poll_cb> for an example.	1372	See C<poll_cb> for an example.
1072		1373
1073	=item IO::AIO::poll_cb	1374	=item IO::AIO::poll_cb
1074		1375
1075	Process some outstanding events on the result pipe. You have to call this	1376	Process some outstanding events on the result pipe. You have to call this
1076	regularly. Returns the number of events processed. Returns immediately	1377	regularly. Returns C<0> if all events could be processed, or C<-1> if it
		1378	returned earlier for whatever reason. Returns immediately when no events
1077	when no events are outstanding. The amount of events processed depends on	1379	are outstanding. The amount of events processed depends on the settings of
1078	the settings of C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>.	1380	C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>.
1079		1381
1080	If not all requests were processed for whatever reason, the filehandle	1382	If not all requests were processed for whatever reason, the filehandle
1081	will still be ready when C<poll_cb> returns.	1383	will still be ready when C<poll_cb> returns, so normally you don't have to
		1384	do anything special to have it called later.
1082		1385
1083	Example: Install an Event watcher that automatically calls	1386	Example: Install an Event watcher that automatically calls
1084	IO::AIO::poll_cb with high priority:	1387	IO::AIO::poll_cb with high priority (more examples can be found in the
		1388	SYNOPSIS section, at the top of this document):
1085		1389
1086	Event->io (fd => IO::AIO::poll_fileno,	1390	Event->io (fd => IO::AIO::poll_fileno,
1087	poll => 'r', async => 1,	1391	poll => 'r', async => 1,
1088	cb => \&IO::AIO::poll_cb);	1392	cb => \&IO::AIO::poll_cb);
		1393
		1394	=item IO::AIO::poll_wait
		1395
		1396	If there are any outstanding requests and none of them in the result
		1397	phase, wait till the result filehandle becomes ready for reading (simply
		1398	does a C<select> on the filehandle. This is useful if you want to
		1399	synchronously wait for some requests to finish).
		1400
		1401	See C<nreqs> for an example.
		1402
		1403	=item IO::AIO::poll
		1404
		1405	Waits until some requests have been handled.
		1406
		1407	Returns the number of requests processed, but is otherwise strictly
		1408	equivalent to:
		1409
		1410	IO::AIO::poll_wait, IO::AIO::poll_cb
		1411
		1412	=item IO::AIO::flush
		1413
		1414	Wait till all outstanding AIO requests have been handled.
		1415
		1416	Strictly equivalent to:
		1417
		1418	IO::AIO::poll_wait, IO::AIO::poll_cb
		1419	while IO::AIO::nreqs;
1089		1420
1090	=item IO::AIO::max_poll_reqs $nreqs	1421	=item IO::AIO::max_poll_reqs $nreqs
1091		1422
1092	=item IO::AIO::max_poll_time $seconds	1423	=item IO::AIO::max_poll_time $seconds
1093		1424
…		…
1118	# use a low priority so other tasks have priority	1449	# use a low priority so other tasks have priority
1119	Event->io (fd => IO::AIO::poll_fileno,	1450	Event->io (fd => IO::AIO::poll_fileno,
1120	poll => 'r', nice => 1,	1451	poll => 'r', nice => 1,
1121	cb => &IO::AIO::poll_cb);	1452	cb => &IO::AIO::poll_cb);
1122		1453
1123	=item IO::AIO::poll_wait
1124
1125	If there are any outstanding requests and none of them in the result
1126	phase, wait till the result filehandle becomes ready for reading (simply
1127	does a C<select> on the filehandle. This is useful if you want to
1128	synchronously wait for some requests to finish).
1129
1130	See C<nreqs> for an example.
1131
1132	=item IO::AIO::poll
1133
1134	Waits until some requests have been handled.
1135
1136	Returns the number of requests processed, but is otherwise strictly
1137	equivalent to:
1138
1139	IO::AIO::poll_wait, IO::AIO::poll_cb
1140
1141	=item IO::AIO::flush
1142
1143	Wait till all outstanding AIO requests have been handled.
1144
1145	Strictly equivalent to:
1146
1147	IO::AIO::poll_wait, IO::AIO::poll_cb
1148	while IO::AIO::nreqs;
1149
1150	=back	1454	=back
1151		1455
1152	=head3 CONTROLLING THE NUMBER OF THREADS	1456	=head3 CONTROLLING THE NUMBER OF THREADS
1153		1457
1154	=over	1458	=over
…		…
1200		1504
1201	The default is probably ok in most situations, especially if thread	1505	The default is probably ok in most situations, especially if thread
1202	creation is fast. If thread creation is very slow on your system you might	1506	creation is fast. If thread creation is very slow on your system you might
1203	want to use larger values.	1507	want to use larger values.
1204		1508
1205	=item $oldmaxreqs = IO::AIO::max_outstanding $maxreqs	1509	=item IO::AIO::max_outstanding $maxreqs
1206		1510
1207	This is a very bad function to use in interactive programs because it	1511	This is a very bad function to use in interactive programs because it
1208	blocks, and a bad way to reduce concurrency because it is inexact: Better	1512	blocks, and a bad way to reduce concurrency because it is inexact: Better
1209	use an C<aio_group> together with a feed callback.	1513	use an C<aio_group> together with a feed callback.
1210		1514
…		…
1215		1519
1216	The default value is very large, so there is no practical limit on the	1520	The default value is very large, so there is no practical limit on the
1217	number of outstanding requests.	1521	number of outstanding requests.
1218		1522
1219	You can still queue as many requests as you want. Therefore,	1523	You can still queue as many requests as you want. Therefore,
1220	C<max_oustsanding> is mainly useful in simple scripts (with low values) or	1524	C<max_outstanding> is mainly useful in simple scripts (with low values) or
1221	as a stop gap to shield against fatal memory overflow (with large values).	1525	as a stop gap to shield against fatal memory overflow (with large values).
1222		1526
1223	=back	1527	=back
1224		1528
1225	=head3 STATISTICAL INFORMATION	1529	=head3 STATISTICAL INFORMATION
…		…
1246	Returns the number of requests currently in the pending state (executed,	1550	Returns the number of requests currently in the pending state (executed,
1247	but not yet processed by poll_cb).	1551	but not yet processed by poll_cb).
1248		1552
1249	=back	1553	=back
1250		1554
		1555	=head3 MISCELLANEOUS FUNCTIONS
		1556
		1557	IO::AIO implements some functions that might be useful, but are not
		1558	asynchronous.
		1559
		1560	=over 4
		1561
		1562	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
		1563
		1564	Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>,
		1565	but is blocking (this makes most sense if you know the input data is
		1566	likely cached already and the output filehandle is set to non-blocking
		1567	operations).
		1568
		1569	Returns the number of bytes copied, or C<-1> on error.
		1570
		1571	=item IO::AIO::fadvise $fh, $offset, $len, $advice
		1572
		1573	Simply calls the C<posix_fadvise> function (see it's
		1574	manpage for details). The following advice constants are
		1575	avaiable: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>,
		1576	C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>,
		1577	C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>.
		1578
		1579	On systems that do not implement C<posix_fadvise>, this function returns
		1580	ENOSYS, otherwise the return value of C<posix_fadvise>.
		1581
		1582	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]
		1583
		1584	Memory-maps a file (or anonymous memory range) and attaches it to the
		1585	given C<$scalar>, which will act like a string scalar.
		1586
		1587	The only operations allowed on the scalar are C<substr>/C<vec> that don't
		1588	change the string length, and most read-only operations such as copying it
		1589	or searching it with regexes and so on.
		1590
		1591	Anything else is unsafe and will, at best, result in memory leaks.
		1592
		1593	The memory map associated with the C<$scalar> is automatically removed
		1594	when the C<$scalar> is destroyed, or when the C<IO::AIO::mmap> or
		1595	C<IO::AIO::munmap> functions are called.
		1596
		1597	This calls the C<mmap>(2) function internally. See your system's manual
		1598	page for details on the C<$length>, C<$prot> and C<$flags> parameters.
		1599
		1600	The C<$length> must be larger than zero and smaller than the actual
		1601	filesize.
		1602
		1603	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,
		1604	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,
		1605
		1606	C<$flags> can be a combination of C<IO::AIO::MAP_SHARED> or
		1607	C<IO::AIO::MAP_PRIVATE>, or a number of system-specific flags (when
		1608	not available, the are defined as 0): C<IO::AIO::MAP_ANONYMOUS>
		1609	(which is set to C<MAP_ANON> if your system only provides this
		1610	constant), C<IO::AIO::MAP_HUGETLB>, C<IO::AIO::MAP_LOCKED>,
		1611	C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or
		1612	C<IO::AIO::MAP_NONBLOCK>
		1613
		1614	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.
		1615
		1616	C<$offset> is the offset from the start of the file - it generally must be
		1617	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.
		1618
		1619	Example:
		1620
		1621	use Digest::MD5;
		1622	use IO::AIO;
		1623
		1624	open my $fh, "<verybigfile"
		1625	or die "$!";
		1626
		1627	IO::AIO::mmap my $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh
		1628	or die "verybigfile: $!";
		1629
		1630	my $fast_md5 = md5 $data;
		1631
		1632	=item IO::AIO::munmap $scalar
		1633
		1634	Removes a previous mmap and undefines the C<$scalar>.
		1635
		1636	=item IO::AIO::munlock $scalar, $offset = 0, $length = undef
		1637
		1638	Calls the C<munlock> function, undoing the effects of a previous
		1639	C<aio_mlock> call (see its description for details).
		1640
		1641	=item IO::AIO::munlockall
		1642
		1643	Calls the C<munlockall> function.
		1644
		1645	On systems that do not implement C<munlockall>, this function returns
		1646	ENOSYS, otherwise the return value of C<munlockall>.
		1647
		1648	=back
		1649
1251	=cut	1650	=cut
1252		1651
1253	# support function to convert a fd into a perl filehandle
1254	sub _fd2fh {
1255	return undef if $_[0] < 0;
1256
1257	# try to generate nice filehandles
1258	my $sym = "IO::AIO::fd#$_[0]";
1259	local *$sym;
1260
1261	open *$sym, "+<&=$_[0]" # usually works under any unix
1262	or open *$sym, "<&=$_[0]" # cygwin needs this
1263	or open *$sym, ">&=$_[0]" # or this
1264	or return undef;
1265
1266	*$sym
1267	}
1268
1269	min_parallel 8;	1652	min_parallel 8;
1270		1653
1271	END { flush }	1654	END { flush }
1272		1655
1273	1;	1656	1;
		1657
		1658	=head1 EVENT LOOP INTEGRATION
		1659
		1660	It is recommended to use L<AnyEvent::AIO> to integrate IO::AIO
		1661	automatically into many event loops:
		1662
		1663	# AnyEvent integration (EV, Event, Glib, Tk, POE, urxvt, pureperl...)
		1664	use AnyEvent::AIO;
		1665
		1666	You can also integrate IO::AIO manually into many event loops, here are
		1667	some examples of how to do this:
		1668
		1669	# EV integration
		1670	my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
		1671
		1672	# Event integration
		1673	Event->io (fd => IO::AIO::poll_fileno,
		1674	poll => 'r',
		1675	cb => \&IO::AIO::poll_cb);
		1676
		1677	# Glib/Gtk2 integration
		1678	add_watch Glib::IO IO::AIO::poll_fileno,
		1679	in => sub { IO::AIO::poll_cb; 1 };
		1680
		1681	# Tk integration
		1682	Tk::Event::IO->fileevent (IO::AIO::poll_fileno, "",
		1683	readable => \&IO::AIO::poll_cb);
		1684
		1685	# Danga::Socket integration
		1686	Danga::Socket->AddOtherFds (IO::AIO::poll_fileno =>
		1687	\&IO::AIO::poll_cb);
1274		1688
1275	=head2 FORK BEHAVIOUR	1689	=head2 FORK BEHAVIOUR
1276		1690
1277	This module should do "the right thing" when the process using it forks:	1691	This module should do "the right thing" when the process using it forks:
1278		1692
…		…
1311		1725
1312	Known bugs will be fixed in the next release.	1726	Known bugs will be fixed in the next release.
1313		1727
1314	=head1 SEE ALSO	1728	=head1 SEE ALSO
1315		1729
1316	L<Coro::AIO>.	1730	L<AnyEvent::AIO> for easy integration into event loops, L<Coro::AIO> for a
		1731	more natural syntax.
1317		1732
1318	=head1 AUTHOR	1733	=head1 AUTHOR
1319		1734
1320	Marc Lehmann <schmorp@schmorp.de>	1735	Marc Lehmann <schmorp@schmorp.de>
1321	http://home.schmorp.de/	1736	http://home.schmorp.de/

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Comparing IO-AIO/AIO.pm (file contents): Revision 1.115 by root, Mon Sep 24 18:14:00 2007 UTC vs. Revision 1.182 by root, Sun Sep 12 03:36:27 2010 UTC

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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.115 by root, Mon Sep 24 18:14:00 2007 UTC vs.
Revision 1.182 by root, Sun Sep 12 03:36:27 2010 UTC