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

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.108 by root, Fri Jun 1 13:25:50 2007 UTC vs.
Revision 1.175 by root, Sun Jan 10 20:37:33 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
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", O_RDONLY, 0, sub {
104	my $fh = shift	82	my $fh = shift
105	or die "error while opening: $!";	83	or die "error while opening: $!";
…		…
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 = '2.4';	173	our $VERSION = '3.5';
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
		181	aio_chmod aio_utime aio_truncate
200	aio_chown aio_chmod aio_utime);	182	aio_msync aio_mtouch aio_statvfs);
		183
201	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice aio_block));	184	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));
202	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush	185	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush
203	min_parallel max_parallel max_idle	186	min_parallel max_parallel max_idle
204	nreqs nready npending nthreads	187	nreqs nready npending nthreads
205	max_poll_time max_poll_reqs);	188	max_poll_time max_poll_reqs
		189	sendfile fadvise);
		190
		191	push @AIO_REQ, qw(aio_busy); # not exported
206		192
207	@IO::AIO::GRP::ISA = 'IO::AIO::REQ';	193	@IO::AIO::GRP::ISA = 'IO::AIO::REQ';
208		194
209	require XSLoader;	195	require XSLoader;
210	XSLoader::load ("IO::AIO", $VERSION);	196	XSLoader::load ("IO::AIO", $VERSION);
211	}	197	}
212		198
213	=head1 FUNCTIONS	199	=head1 FUNCTIONS
		200
		201	=head2 QUICK OVERVIEW
		202
		203	This section simply lists the prototypes of the most important functions
		204	for quick reference. See the following sections for function-by-function
		205	documentation.
		206
		207	aio_open $pathname, $flags, $mode, $callback->($fh)
		208	aio_close $fh, $callback->($status)
		209	aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
		210	aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
		211	aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
		212	aio_readahead $fh,$offset,$length, $callback->($retval)
		213	aio_stat $fh_or_path, $callback->($status)
		214	aio_lstat $fh, $callback->($status)
		215	aio_statvfs $fh_or_path, $callback->($statvfs)
		216	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
		217	aio_chown $fh_or_path, $uid, $gid, $callback->($status)
		218	aio_truncate $fh_or_path, $offset, $callback->($status)
		219	aio_chmod $fh_or_path, $mode, $callback->($status)
		220	aio_unlink $pathname, $callback->($status)
		221	aio_mknod $path, $mode, $dev, $callback->($status)
		222	aio_link $srcpath, $dstpath, $callback->($status)
		223	aio_symlink $srcpath, $dstpath, $callback->($status)
		224	aio_readlink $path, $callback->($link)
		225	aio_rename $srcpath, $dstpath, $callback->($status)
		226	aio_mkdir $pathname, $mode, $callback->($status)
		227	aio_rmdir $pathname, $callback->($status)
		228	aio_readdir $pathname, $callback->($entries)
		229	aio_readdirx $pathname, $flags, $callback->($entries, $flags)
		230	IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST
		231	IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN
		232	aio_load $path, $data, $callback->($status)
		233	aio_copy $srcpath, $dstpath, $callback->($status)
		234	aio_move $srcpath, $dstpath, $callback->($status)
		235	aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
		236	aio_rmtree $path, $callback->($status)
		237	aio_sync $callback->($status)
		238	aio_fsync $fh, $callback->($status)
		239	aio_fdatasync $fh, $callback->($status)
		240	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
		241	aio_pathsync $path, $callback->($status)
		242	aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
		243	aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
		244	aio_group $callback->(...)
		245	aio_nop $callback->()
		246
		247	$prev_pri = aioreq_pri [$pri]
		248	aioreq_nice $pri_adjust
		249
		250	IO::AIO::poll_wait
		251	IO::AIO::poll_cb
		252	IO::AIO::poll
		253	IO::AIO::flush
		254	IO::AIO::max_poll_reqs $nreqs
		255	IO::AIO::max_poll_time $seconds
		256	IO::AIO::min_parallel $nthreads
		257	IO::AIO::max_parallel $nthreads
		258	IO::AIO::max_idle $nthreads
		259	IO::AIO::max_outstanding $maxreqs
		260	IO::AIO::nreqs
		261	IO::AIO::nready
		262	IO::AIO::npending
		263
		264	IO::AIO::sendfile $ofh, $ifh, $offset, $count
		265	IO::AIO::fadvise $fh, $offset, $len, $advice
		266	IO::AIO::mlockall $flags
		267	IO::AIO::munlockall
214		268
215	=head2 AIO REQUEST FUNCTIONS	269	=head2 AIO REQUEST FUNCTIONS
216		270
217	All the C<aio_*> calls are more or less thin wrappers around the syscall	271	All the C<aio_*> calls are more or less thin wrappers around the syscall
218	with the same name (sans C<aio_>). The arguments are similar or identical,	272	with the same name (sans C<aio_>). The arguments are similar or identical,
219	and they all accept an additional (and optional) C<$callback> argument	273	and they all accept an additional (and optional) C<$callback> argument
220	which must be a code reference. This code reference will get called with	274	which must be a code reference. This code reference will get called with
221	the syscall return code (e.g. most syscalls return C<-1> on error, unlike	275	the syscall return code (e.g. most syscalls return C<-1> on error, unlike
222	perl, which usually delivers "false") as it's sole argument when the given	276	perl, which usually delivers "false") as its sole argument after the given
223	syscall has been executed asynchronously.	277	syscall has been executed asynchronously.
224		278
225	All functions expecting a filehandle keep a copy of the filehandle	279	All functions expecting a filehandle keep a copy of the filehandle
226	internally until the request has finished.	280	internally until the request has finished.
227		281
…		…
241	your pathnames to the locale (or other) encoding in effect in the user	295	your pathnames to the locale (or other) encoding in effect in the user
242	environment, d) use Glib::filename_from_unicode on unicode filenames or e)	296	environment, d) use Glib::filename_from_unicode on unicode filenames or e)
243	use something else to ensure your scalar has the correct contents.	297	use something else to ensure your scalar has the correct contents.
244		298
245	This works, btw. independent of the internal UTF-8 bit, which IO::AIO	299	This works, btw. independent of the internal UTF-8 bit, which IO::AIO
246	handles correctly wether it is set or not.	300	handles correctly whether it is set or not.
247		301
248	=over 4	302	=over 4
249		303
250	=item $prev_pri = aioreq_pri [$pri]	304	=item $prev_pri = aioreq_pri [$pri]
251		305
…		…
311		365
312		366
313	=item aio_close $fh, $callback->($status)	367	=item aio_close $fh, $callback->($status)
314		368
315	Asynchronously close a file and call the callback with the result	369	Asynchronously close a file and call the callback with the result
316	code. I<WARNING:> although accepted, you should not pass in a perl	370	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		371
321	This is supposed to be a bug in the API, so that might change. It's	372	Unfortunately, you can't do this to perl. Perl I<insists> very strongly on
322	therefore best to avoid this function.	373	closing the file descriptor associated with the filehandle itself.
323		374
		375	Therefore, C<aio_close> will not close the filehandle - instead it will
		376	use dup2 to overwrite the file descriptor with the write-end of a pipe
		377	(the pipe fd will be created on demand and will be cached).
		378
		379	Or in other words: the file descriptor will be closed, but it will not be
		380	free for reuse until the perl filehandle is closed.
		381
		382	=cut
324		383
325	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	384	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
326		385
327	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	386	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
328		387
329	Reads or writes C<length> bytes from the specified C<fh> and C<offset>	388	Reads or writes C<$length> bytes from or to the specified C<$fh> and
330	into the scalar given by C<data> and offset C<dataoffset> and calls the	389	C<$offset> into the scalar given by C<$data> and offset C<$dataoffset>
331	callback without the actual number of bytes read (or -1 on error, just	390	and calls the callback without the actual number of bytes read (or -1 on
		391	error, just like the syscall).
		392
		393	C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to
		394	offset plus the actual number of bytes read.
		395
332	like the syscall). If C<offset> is undefined, then the current file offset	396	If C<$offset> is undefined, then the current file descriptor offset will
333	will be used (and updated), otherwise the file offset will not be changed	397	be used (and updated), otherwise the file descriptor offset will not be
334	by these calls.	398	changed by these calls.
		399
		400	If C<$length> is undefined in C<aio_write>, use the remaining length of
		401	C<$data>.
		402
		403	If C<$dataoffset> is less than zero, it will be counted from the end of
		404	C<$data>.
335		405
336	The C<$data> scalar I<MUST NOT> be modified in any way while the request	406	The C<$data> scalar I<MUST NOT> be modified in any way while the request
337	is outstanding. Modifying it can result in segfaults or World War III (if	407	is outstanding. Modifying it can result in segfaults or World War III (if
338	the necessary/optional hardware is installed).	408	the necessary/optional hardware is installed).
339		409
…		…
356		426
357	This call tries to make use of a native C<sendfile> syscall to provide	427	This call tries to make use of a native C<sendfile> syscall to provide
358	zero-copy operation. For this to work, C<$out_fh> should refer to a	428	zero-copy operation. For this to work, C<$out_fh> should refer to a
359	socket, and C<$in_fh> should refer to mmap'able file.	429	socket, and C<$in_fh> should refer to mmap'able file.
360		430
361	If the native sendfile call fails or is not implemented, it will be	431	If a native sendfile cannot be found or it fails with C<ENOSYS>,
		432	C<ENOTSUP>, C<EOPNOTSUPP>, C<EAFNOSUPPORT>, C<EPROTOTYPE> or C<ENOTSOCK>,
362	emulated, so you can call C<aio_sendfile> on any type of filehandle	433	it will be emulated, so you can call C<aio_sendfile> on any type of
363	regardless of the limitations of the operating system.	434	filehandle regardless of the limitations of the operating system.
364		435
365	Please note, however, that C<aio_sendfile> can read more bytes from	436	Please note, however, that C<aio_sendfile> can read more bytes from
366	C<$in_fh> than are written, and there is no way to find out how many	437	C<$in_fh> than are written, and there is no way to find out how many
367	bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only	438	bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only
368	provides the number of bytes written to C<$out_fh>. Only if the result	439	provides the number of bytes written to C<$out_fh>. Only if the result
…		…
406	$_[0] and die "stat failed: $!";	477	$_[0] and die "stat failed: $!";
407	print "size is ", -s _, "\n";	478	print "size is ", -s _, "\n";
408	};	479	};
409		480
410		481
		482	=item aio_statvfs $fh_or_path, $callback->($statvfs)
		483
		484	Works like the POSIX C<statvfs> or C<fstatvfs> syscalls, depending on
		485	whether a file handle or path was passed.
		486
		487	On success, the callback is passed a hash reference with the following
		488	members: C<bsize>, C<frsize>, C<blocks>, C<bfree>, C<bavail>, C<files>,
		489	C<ffree>, C<favail>, C<fsid>, C<flag> and C<namemax>. On failure, C<undef>
		490	is passed.
		491
		492	The following POSIX IO::AIO::ST_* constants are defined: C<ST_RDONLY> and
		493	C<ST_NOSUID>.
		494
		495	The following non-POSIX IO::AIO::ST_* flag masks are defined to
		496	their correct value when available, or to C<0> on systems that do
		497	not support them: C<ST_NODEV>, C<ST_NOEXEC>, C<ST_SYNCHRONOUS>,
		498	C<ST_MANDLOCK>, C<ST_WRITE>, C<ST_APPEND>, C<ST_IMMUTABLE>, C<ST_NOATIME>,
		499	C<ST_NODIRATIME> and C<ST_RELATIME>.
		500
		501	Example: stat C</wd> and dump out the data if successful.
		502
		503	aio_statvfs "/wd", sub {
		504	my $f = $_[0]
		505	or die "statvfs: $!";
		506
		507	use Data::Dumper;
		508	say Dumper $f;
		509	};
		510
		511	# result:
		512	{
		513	bsize => 1024,
		514	bfree => 4333064312,
		515	blocks => 10253828096,
		516	files => 2050765568,
		517	flag => 4096,
		518	favail => 2042092649,
		519	bavail => 4333064312,
		520	ffree => 2042092649,
		521	namemax => 255,
		522	frsize => 1024,
		523	fsid => 1810
		524	}
		525
		526
411	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	527	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
412		528
413	Works like perl's C<utime> function (including the special case of $atime	529	Works like perl's C<utime> function (including the special case of $atime
414	and $mtime being undef). Fractional times are supported if the underlying	530	and $mtime being undef). Fractional times are supported if the underlying
415	syscalls support them.	531	syscalls support them.
…		…
437	aio_chown "path", 0, -1;	553	aio_chown "path", 0, -1;
438	# same as above:	554	# same as above:
439	aio_chown "path", 0, undef;	555	aio_chown "path", 0, undef;
440		556
441		557
		558	=item aio_truncate $fh_or_path, $offset, $callback->($status)
		559
		560	Works like truncate(2) or ftruncate(2).
		561
		562
442	=item aio_chmod $fh_or_path, $mode, $callback->($status)	563	=item aio_chmod $fh_or_path, $mode, $callback->($status)
443		564
444	Works like perl's C<chmod> function.	565	Works like perl's C<chmod> function.
445		566
446		567
…		…
503		624
504	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire	625	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire
505	directory (i.e. opendir + readdir + closedir). The entries will not be	626	directory (i.e. opendir + readdir + closedir). The entries will not be
506	sorted, and will B<NOT> include the C<.> and C<..> entries.	627	sorted, and will B<NOT> include the C<.> and C<..> entries.
507		628
508	The callback a single argument which is either C<undef> or an array-ref	629	The callback is passed a single argument which is either C<undef> or an
509	with the filenames.	630	array-ref with the filenames.
		631
		632
		633	=item aio_readdirx $pathname, $flags, $callback->($entries, $flags)
		634
		635	Quite similar to C<aio_readdir>, but the C<$flags> argument allows to tune
		636	behaviour and output format. In case of an error, C<$entries> will be
		637	C<undef>.
		638
		639	The flags are a combination of the following constants, ORed together (the
		640	flags will also be passed to the callback, possibly modified):
		641
		642	=over 4
		643
		644	=item IO::AIO::READDIR_DENTS
		645
		646	When this flag is off, then the callback gets an arrayref with of names
		647	only (as with C<aio_readdir>), otherwise it gets an arrayref with
		648	C<[$name, $type, $inode]> arrayrefs, each describing a single directory
		649	entry in more detail.
		650
		651	C<$name> is the name of the entry.
		652
		653	C<$type> is one of the C<IO::AIO::DT_xxx> constants:
		654
		655	C<IO::AIO::DT_UNKNOWN>, C<IO::AIO::DT_FIFO>, C<IO::AIO::DT_CHR>, C<IO::AIO::DT_DIR>,
		656	C<IO::AIO::DT_BLK>, C<IO::AIO::DT_REG>, C<IO::AIO::DT_LNK>, C<IO::AIO::DT_SOCK>,
		657	C<IO::AIO::DT_WHT>.
		658
		659	C<IO::AIO::DT_UNKNOWN> means just that: readdir does not know. If you need to
		660	know, you have to run stat yourself. Also, for speed reasons, the C<$type>
		661	scalars are read-only: you can not modify them.
		662
		663	C<$inode> is the inode number (which might not be exact on systems with 64
		664	bit inode numbers and 32 bit perls). This field has unspecified content on
		665	systems that do not deliver the inode information.
		666
		667	=item IO::AIO::READDIR_DIRS_FIRST
		668
		669	When this flag is set, then the names will be returned in an order where
		670	likely directories come first. This is useful when you need to quickly
		671	find directories, or you want to find all directories while avoiding to
		672	stat() each entry.
		673
		674	If the system returns type information in readdir, then this is used
		675	to find directories directly. Otherwise, likely directories are files
		676	beginning with ".", or otherwise files with no dots, of which files with
		677	short names are tried first.
		678
		679	=item IO::AIO::READDIR_STAT_ORDER
		680
		681	When this flag is set, then the names will be returned in an order
		682	suitable for stat()'ing each one. That is, when you plan to stat()
		683	all files in the given directory, then the returned order will likely
		684	be fastest.
		685
		686	If both this flag and C<IO::AIO::READDIR_DIRS_FIRST> are specified, then
		687	the likely dirs come first, resulting in a less optimal stat order.
		688
		689	=item IO::AIO::READDIR_FOUND_UNKNOWN
		690
		691	This flag should not be set when calling C<aio_readdirx>. Instead, it
		692	is being set by C<aio_readdirx>, when any of the C<$type>'s found were
		693	C<IO::AIO::DT_UNKNOWN>. The absense of this flag therefore indicates that all
		694	C<$type>'s are known, which can be used to speed up some algorithms.
		695
		696	=back
510		697
511		698
512	=item aio_load $path, $data, $callback->($status)	699	=item aio_load $path, $data, $callback->($status)
513		700
514	This is a composite request that tries to fully load the given file into	701	This is a composite request that tries to fully load the given file into
515	memory. Status is the same as with aio_read.	702	memory. Status is the same as with aio_read.
516		703
517	=cut	704	=cut
518		705
519	sub aio_load($$;$) {	706	sub aio_load($$;$) {
520	aio_block {
521	my ($path, undef, $cb) = @_;	707	my ($path, undef, $cb) = @_;
522	my $data = \$_[1];	708	my $data = \$_[1];
523		709
524	my $pri = aioreq_pri;	710	my $pri = aioreq_pri;
525	my $grp = aio_group $cb;	711	my $grp = aio_group $cb;
		712
		713	aioreq_pri $pri;
		714	add $grp aio_open $path, O_RDONLY, 0, sub {
		715	my $fh = shift
		716	or return $grp->result (-1);
526		717
527	aioreq_pri $pri;	718	aioreq_pri $pri;
528	add $grp aio_open $path, O_RDONLY, 0, sub {
529	my $fh = shift
530	or return $grp->result (-1);
531
532	aioreq_pri $pri;
533	add $grp aio_read $fh, 0, (-s $fh), $$data, 0, sub {	719	add $grp aio_read $fh, 0, (-s $fh), $$data, 0, sub {
534	$grp->result ($_[0]);	720	$grp->result ($_[0]);
535	};
536	};	721	};
537
538	$grp
539	}	722	};
		723
		724	$grp
540	}	725	}
541		726
542	=item aio_copy $srcpath, $dstpath, $callback->($status)	727	=item aio_copy $srcpath, $dstpath, $callback->($status)
543		728
544	Try to copy the I<file> (directories not supported as either source or	729	Try to copy the I<file> (directories not supported as either source or
545	destination) from C<$srcpath> to C<$dstpath> and call the callback with	730	destination) from C<$srcpath> to C<$dstpath> and call the callback with
546	the C<0> (error) or C<-1> ok.	731	a status of C<0> (ok) or C<-1> (error, see C<$!>).
547		732
548	This is a composite request that it creates the destination file with	733	This is a composite request that creates the destination file with
549	mode 0200 and copies the contents of the source file into it using	734	mode 0200 and copies the contents of the source file into it using
550	C<aio_sendfile>, followed by restoring atime, mtime, access mode and	735	C<aio_sendfile>, followed by restoring atime, mtime, access mode and
551	uid/gid, in that order.	736	uid/gid, in that order.
552		737
553	If an error occurs, the partial destination file will be unlinked, if	738	If an error occurs, the partial destination file will be unlinked, if
…		…
555	errors are being ignored.	740	errors are being ignored.
556		741
557	=cut	742	=cut
558		743
559	sub aio_copy($$;$) {	744	sub aio_copy($$;$) {
560	aio_block {
561	my ($src, $dst, $cb) = @_;	745	my ($src, $dst, $cb) = @_;
562		746
563	my $pri = aioreq_pri;	747	my $pri = aioreq_pri;
564	my $grp = aio_group $cb;	748	my $grp = aio_group $cb;
565		749
566	aioreq_pri $pri;	750	aioreq_pri $pri;
567	add $grp aio_open $src, O_RDONLY, 0, sub {	751	add $grp aio_open $src, O_RDONLY, 0, sub {
568	if (my $src_fh = $_[0]) {	752	if (my $src_fh = $_[0]) {
569	my @stat = stat $src_fh;	753	my @stat = stat $src_fh; # hmm, might block over nfs?
570		754
571	aioreq_pri $pri;	755	aioreq_pri $pri;
572	add $grp aio_open $dst, O_CREAT \| O_WRONLY \| O_TRUNC, 0200, sub {	756	add $grp aio_open $dst, O_CREAT \| O_WRONLY \| O_TRUNC, 0200, sub {
573	if (my $dst_fh = $_[0]) {	757	if (my $dst_fh = $_[0]) {
574	aioreq_pri $pri;	758	aioreq_pri $pri;
575	add $grp aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub {	759	add $grp aio_sendfile $dst_fh, $src_fh, 0, $stat[7], sub {
576	if ($_[0] == $stat[7]) {	760	if ($_[0] == $stat[7]) {
577	$grp->result (0);	761	$grp->result (0);
578	close $src_fh;	762	close $src_fh;
579		763
580	# those should not normally block. should. should.
581	utime $stat[8], $stat[9], $dst;
582	chmod $stat[2] & 07777, $dst_fh;
583	chown $stat[4], $stat[5], $dst_fh;
584	close $dst_fh;
585	} else {	764	my $ch = sub {
586	$grp->result (-1);
587	close $src_fh;
588	close $dst_fh;
589
590	aioreq $pri;	765	aioreq_pri $pri;
		766	add $grp aio_chmod $dst_fh, $stat[2] & 07777, sub {
		767	aioreq_pri $pri;
		768	add $grp aio_chown $dst_fh, $stat[4], $stat[5], sub {
		769	aioreq_pri $pri;
591	add $grp aio_unlink $dst;	770	add $grp aio_close $dst_fh;
		771	}
		772	};
592	}	773	};
		774
		775	aioreq_pri $pri;
		776	add $grp aio_utime $dst_fh, $stat[8], $stat[9], sub {
		777	if ($_[0] < 0 && $! == ENOSYS) {
		778	aioreq_pri $pri;
		779	add $grp aio_utime $dst, $stat[8], $stat[9], $ch;
		780	} else {
		781	$ch->();
		782	}
		783	};
		784	} else {
		785	$grp->result (-1);
		786	close $src_fh;
		787	close $dst_fh;
		788
		789	aioreq $pri;
		790	add $grp aio_unlink $dst;
593	};	791	}
594	} else {
595	$grp->result (-1);
596	}	792	};
		793	} else {
		794	$grp->result (-1);
597	},	795	}
598
599	} else {
600	$grp->result (-1);
601	}	796	},
		797
		798	} else {
		799	$grp->result (-1);
602	};	800	}
603
604	$grp
605	}	801	};
		802
		803	$grp
606	}	804	}
607		805
608	=item aio_move $srcpath, $dstpath, $callback->($status)	806	=item aio_move $srcpath, $dstpath, $callback->($status)
609		807
610	Try to move the I<file> (directories not supported as either source or	808	Try to move the I<file> (directories not supported as either source or
611	destination) from C<$srcpath> to C<$dstpath> and call the callback with	809	destination) from C<$srcpath> to C<$dstpath> and call the callback with
612	the C<0> (error) or C<-1> ok.	810	a status of C<0> (ok) or C<-1> (error, see C<$!>).
613		811
614	This is a composite request that tries to rename(2) the file first. If	812	This is a composite request that tries to rename(2) the file first; if
615	rename files with C<EXDEV>, it copies the file with C<aio_copy> and, if	813	rename fails with C<EXDEV>, it copies the file with C<aio_copy> and, if
616	that is successful, unlinking the C<$srcpath>.	814	that is successful, unlinks the C<$srcpath>.
617		815
618	=cut	816	=cut
619		817
620	sub aio_move($$;$) {	818	sub aio_move($$;$) {
621	aio_block {
622	my ($src, $dst, $cb) = @_;	819	my ($src, $dst, $cb) = @_;
623		820
624	my $pri = aioreq_pri;	821	my $pri = aioreq_pri;
625	my $grp = aio_group $cb;	822	my $grp = aio_group $cb;
626		823
627	aioreq_pri $pri;	824	aioreq_pri $pri;
628	add $grp aio_rename $src, $dst, sub {	825	add $grp aio_rename $src, $dst, sub {
629	if ($_[0] && $! == EXDEV) {	826	if ($_[0] && $! == EXDEV) {
630	aioreq_pri $pri;	827	aioreq_pri $pri;
631	add $grp aio_copy $src, $dst, sub {	828	add $grp aio_copy $src, $dst, sub {
632	$grp->result ($_[0]);
633
634	if (!$_[0]) {
635	aioreq_pri $pri;
636	add $grp aio_unlink $src;
637	}
638	};
639	} else {
640	$grp->result ($_[0]);	829	$grp->result ($_[0]);
		830
		831	if (!$_[0]) {
		832	aioreq_pri $pri;
		833	add $grp aio_unlink $src;
		834	}
641	}	835	};
		836	} else {
		837	$grp->result ($_[0]);
642	};	838	}
643
644	$grp
645	}	839	};
		840
		841	$grp
646	}	842	}
647		843
648	=item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)	844	=item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
649		845
650	Scans a directory (similar to C<aio_readdir>) but additionally tries to	846	Scans a directory (similar to C<aio_readdir>) but additionally tries to
…		…
670		866
671	Implementation notes.	867	Implementation notes.
672		868
673	The C<aio_readdir> cannot be avoided, but C<stat()>'ing every entry can.	869	The C<aio_readdir> cannot be avoided, but C<stat()>'ing every entry can.
674		870
		871	If readdir returns file type information, then this is used directly to
		872	find directories.
		873
675	After reading the directory, the modification time, size etc. of the	874	Otherwise, after reading the directory, the modification time, size etc.
676	directory before and after the readdir is checked, and if they match (and	875	of the directory before and after the readdir is checked, and if they
677	isn't the current time), the link count will be used to decide how many	876	match (and isn't the current time), the link count will be used to decide
678	entries are directories (if >= 2). Otherwise, no knowledge of the number	877	how many entries are directories (if >= 2). Otherwise, no knowledge of the
679	of subdirectories will be assumed.	878	number of subdirectories will be assumed.
680		879
681	Then entries will be sorted into likely directories (everything without	880	Then entries will be sorted into likely directories a non-initial dot
682	a non-initial dot currently) and likely non-directories (everything	881	currently) and likely non-directories (see C<aio_readdirx>). Then every
683	else). Then every entry plus an appended C</.> will be C<stat>'ed,	882	entry plus an appended C</.> will be C<stat>'ed, likely directories first,
684	likely directories first. If that succeeds, it assumes that the entry	883	in order of their inode numbers. If that succeeds, it assumes that the
685	is a directory or a symlink to directory (which will be checked	884	entry is a directory or a symlink to directory (which will be checked
686	seperately). This is often faster than stat'ing the entry itself because	885	seperately). This is often faster than stat'ing the entry itself because
687	filesystems might detect the type of the entry without reading the inode	886	filesystems might detect the type of the entry without reading the inode
688	data (e.g. ext2fs filetype feature).	887	data (e.g. ext2fs filetype feature), even on systems that cannot return
		888	the filetype information on readdir.
689		889
690	If the known number of directories (link count - 2) has been reached, the	890	If the known number of directories (link count - 2) has been reached, the
691	rest of the entries is assumed to be non-directories.	891	rest of the entries is assumed to be non-directories.
692		892
693	This only works with certainty on POSIX (= UNIX) filesystems, which	893	This only works with certainty on POSIX (= UNIX) filesystems, which
…		…
698	directory counting heuristic.	898	directory counting heuristic.
699		899
700	=cut	900	=cut
701		901
702	sub aio_scandir($$;$) {	902	sub aio_scandir($$;$) {
703	aio_block {
704	my ($path, $maxreq, $cb) = @_;	903	my ($path, $maxreq, $cb) = @_;
705		904
706	my $pri = aioreq_pri;	905	my $pri = aioreq_pri;
707		906
708	my $grp = aio_group $cb;	907	my $grp = aio_group $cb;
709		908
710	$maxreq = 4 if $maxreq <= 0;	909	$maxreq = 4 if $maxreq <= 0;
711		910
712	# stat once	911	# stat once
		912	aioreq_pri $pri;
		913	add $grp aio_stat $path, sub {
		914	return $grp->result () if $_[0];
		915	my $now = time;
		916	my $hash1 = join ":", (stat _)[0,1,3,7,9];
		917
		918	# read the directory entries
713	aioreq_pri $pri;	919	aioreq_pri $pri;
714	add $grp aio_stat $path, sub {	920	add $grp aio_readdirx $path, READDIR_DIRS_FIRST, sub {
		921	my $entries = shift
715	return $grp->result () if $_[0];	922	or return $grp->result ();
716	my $now = time;
717	my $hash1 = join ":", (stat _)[0,1,3,7,9];
718		923
719	# read the directory entries	924	# stat the dir another time
720	aioreq_pri $pri;	925	aioreq_pri $pri;
721	add $grp aio_readdir $path, sub {
722	my $entries = shift
723	or return $grp->result ();
724
725	# stat the dir another time
726	aioreq_pri $pri;
727	add $grp aio_stat $path, sub {	926	add $grp aio_stat $path, sub {
728	my $hash2 = join ":", (stat _)[0,1,3,7,9];	927	my $hash2 = join ":", (stat _)[0,1,3,7,9];
729		928
730	my $ndirs;	929	my $ndirs;
731		930
732	# take the slow route if anything looks fishy	931	# take the slow route if anything looks fishy
733	if ($hash1 ne $hash2 or (stat _)[9] == $now) {	932	if ($hash1 ne $hash2 or (stat _)[9] == $now) {
734	$ndirs = -1;	933	$ndirs = -1;
735	} else {	934	} else {
736	# if nlink == 2, we are finished	935	# if nlink == 2, we are finished
737	# on non-posix-fs's, we rely on nlink < 2	936	# for non-posix-fs's, we rely on nlink < 2
738	$ndirs = (stat _)[3] - 2	937	$ndirs = (stat _)[3] - 2
739	or return $grp->result ([], $entries);	938	or return $grp->result ([], $entries);
740	}	939	}
741		940
742	# sort into likely dirs and likely nondirs
743	# dirs == files without ".", short entries first
744	$entries = [map $_->[0],
745	sort { $b->[1] cmp $a->[1] }
746	map [$_, sprintf "%s%04d", (/.\./ ? "1" : "0"), length],
747	@$entries];
748
749	my (@dirs, @nondirs);	941	my (@dirs, @nondirs);
750		942
751	my $statgrp = add $grp aio_group sub {	943	my $statgrp = add $grp aio_group sub {
752	$grp->result (\@dirs, \@nondirs);	944	$grp->result (\@dirs, \@nondirs);
753	};	945	};
754		946
755	limit $statgrp $maxreq;	947	limit $statgrp $maxreq;
756	feed $statgrp sub {	948	feed $statgrp sub {
757	return unless @$entries;	949	return unless @$entries;
758	my $entry = pop @$entries;	950	my $entry = shift @$entries;
759		951
760	aioreq_pri $pri;	952	aioreq_pri $pri;
761	add $statgrp aio_stat "$path/$entry/.", sub {	953	add $statgrp aio_stat "$path/$entry/.", sub {
762	if ($_[0] < 0) {	954	if ($_[0] < 0) {
763	push @nondirs, $entry;	955	push @nondirs, $entry;
764	} else {	956	} else {
765	# need to check for real directory	957	# need to check for real directory
766	aioreq_pri $pri;	958	aioreq_pri $pri;
767	add $statgrp aio_lstat "$path/$entry", sub {	959	add $statgrp aio_lstat "$path/$entry", sub {
768	if (-d _) {	960	if (-d _) {
769	push @dirs, $entry;	961	push @dirs, $entry;
770		962
771	unless (--$ndirs) {	963	unless (--$ndirs) {
772	push @nondirs, @$entries;	964	push @nondirs, @$entries;
773	feed $statgrp;	965	feed $statgrp;
774	}
775	} else {
776	push @nondirs, $entry;
777	}	966	}
		967	} else {
		968	push @nondirs, $entry;
778	}	969	}
779	}	970	}
780	};	971	}
781	};	972	};
782	};	973	};
783	};	974	};
784	};	975	};
785
786	$grp
787	}	976	};
		977
		978	$grp
788	}	979	}
789		980
790	=item aio_rmtree $path, $callback->($status)	981	=item aio_rmtree $path, $callback->($status)
791		982
792	Delete a directory tree starting (and including) C<$path>, return the	983	Delete a directory tree starting (and including) C<$path>, return the
…		…
796		987
797	=cut	988	=cut
798		989
799	sub aio_rmtree;	990	sub aio_rmtree;
800	sub aio_rmtree($;$) {	991	sub aio_rmtree($;$) {
801	aio_block {
802	my ($path, $cb) = @_;	992	my ($path, $cb) = @_;
803		993
804	my $pri = aioreq_pri;	994	my $pri = aioreq_pri;
805	my $grp = aio_group $cb;	995	my $grp = aio_group $cb;
806		996
807	aioreq_pri $pri;	997	aioreq_pri $pri;
808	add $grp aio_scandir $path, 0, sub {	998	add $grp aio_scandir $path, 0, sub {
809	my ($dirs, $nondirs) = @_;	999	my ($dirs, $nondirs) = @_;
810		1000
811	my $dirgrp = aio_group sub {	1001	my $dirgrp = aio_group sub {
812	add $grp aio_rmdir $path, sub {	1002	add $grp aio_rmdir $path, sub {
813	$grp->result ($_[0]);	1003	$grp->result ($_[0]);
814	};
815	};	1004	};
816
817	(aioreq_pri $pri), add $dirgrp aio_rmtree "$path/$_" for @$dirs;
818	(aioreq_pri $pri), add $dirgrp aio_unlink "$path/$_" for @$nondirs;
819
820	add $grp $dirgrp;
821	};	1005	};
822		1006
823	$grp	1007	(aioreq_pri $pri), add $dirgrp aio_rmtree "$path/$_" for @$dirs;
		1008	(aioreq_pri $pri), add $dirgrp aio_unlink "$path/$_" for @$nondirs;
		1009
		1010	add $grp $dirgrp;
824	}	1011	};
		1012
		1013	$grp
825	}	1014	}
		1015
		1016	=item aio_sync $callback->($status)
		1017
		1018	Asynchronously call sync and call the callback when finished.
826		1019
827	=item aio_fsync $fh, $callback->($status)	1020	=item aio_fsync $fh, $callback->($status)
828		1021
829	Asynchronously call fsync on the given filehandle and call the callback	1022	Asynchronously call fsync on the given filehandle and call the callback
830	with the fsync result code.	1023	with the fsync result code.
…		…
834	Asynchronously call fdatasync on the given filehandle and call the	1027	Asynchronously call fdatasync on the given filehandle and call the
835	callback with the fdatasync result code.	1028	callback with the fdatasync result code.
836		1029
837	If this call isn't available because your OS lacks it or it couldn't be	1030	If this call isn't available because your OS lacks it or it couldn't be
838	detected, it will be emulated by calling C<fsync> instead.	1031	detected, it will be emulated by calling C<fsync> instead.
		1032
		1033	=item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
		1034
		1035	Sync the data portion of the file specified by C<$offset> and C<$length>
		1036	to disk (but NOT the metadata), by calling the Linux-specific
		1037	sync_file_range call. If sync_file_range is not available or it returns
		1038	ENOSYS, then fdatasync or fsync is being substituted.
		1039
		1040	C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>,
		1041	C<IO::AIO::SYNC_FILE_RANGE_WRITE> and
		1042	C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range
		1043	manpage for details.
		1044
		1045	=item aio_pathsync $path, $callback->($status)
		1046
		1047	This request tries to open, fsync and close the given path. This is a
		1048	composite request intended to sync directories after directory operations
		1049	(E.g. rename). This might not work on all operating systems or have any
		1050	specific effect, but usually it makes sure that directory changes get
		1051	written to disc. It works for anything that can be opened for read-only,
		1052	not just directories.
		1053
		1054	Future versions of this function might fall back to other methods when
		1055	C<fsync> on the directory fails (such as calling C<sync>).
		1056
		1057	Passes C<0> when everything went ok, and C<-1> on error.
		1058
		1059	=cut
		1060
		1061	sub aio_pathsync($;$) {
		1062	my ($path, $cb) = @_;
		1063
		1064	my $pri = aioreq_pri;
		1065	my $grp = aio_group $cb;
		1066
		1067	aioreq_pri $pri;
		1068	add $grp aio_open $path, O_RDONLY, 0, sub {
		1069	my ($fh) = @_;
		1070	if ($fh) {
		1071	aioreq_pri $pri;
		1072	add $grp aio_fsync $fh, sub {
		1073	$grp->result ($_[0]);
		1074
		1075	aioreq_pri $pri;
		1076	add $grp aio_close $fh;
		1077	};
		1078	} else {
		1079	$grp->result (-1);
		1080	}
		1081	};
		1082
		1083	$grp
		1084	}
		1085
		1086	=item aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
		1087
		1088	This is a rather advanced IO::AIO call, which only works on mmap(2)ed
		1089	scalars (see the L<Sys::Mmap> or L<Mmap> modules for details on this, note
		1090	that the scalar must only be modified in-place while an aio operation is
		1091	pending on it).
		1092
		1093	It calls the C<msync> function of your OS, if available, with the memory
		1094	area starting at C<$offset> in the string and ending C<$length> bytes
		1095	later. If C<$length> is negative, counts from the end, and if C<$length>
		1096	is C<undef>, then it goes till the end of the string. The flags can be
		1097	a combination of C<IO::AIO::MS_ASYNC>, C<IO::AIO::MS_INVALIDATE> and
		1098	C<IO::AIO::MS_SYNC>.
		1099
		1100	=item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
		1101
		1102	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
		1103	scalars.
		1104
		1105	It touches (reads or writes) all memory pages in the specified
		1106	range inside the scalar. All caveats and parameters are the same
		1107	as for C<aio_msync>, above, except for flags, which must be either
		1108	C<0> (which reads all pages and ensures they are instantiated) or
		1109	C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and
		1110	writing an octet from it, which dirties the page).
839		1111
840	=item aio_group $callback->(...)	1112	=item aio_group $callback->(...)
841		1113
842	This is a very special aio request: Instead of doing something, it is a	1114	This is a very special aio request: Instead of doing something, it is a
843	container for other aio requests, which is useful if you want to bundle	1115	container for other aio requests, which is useful if you want to bundle
…		…
893	=item cancel $req	1165	=item cancel $req
894		1166
895	Cancels the request, if possible. Has the effect of skipping execution	1167	Cancels the request, if possible. Has the effect of skipping execution
896	when entering the B<execute> state and skipping calling the callback when	1168	when entering the B<execute> state and skipping calling the callback when
897	entering the the B<result> state, but will leave the request otherwise	1169	entering the the B<result> state, but will leave the request otherwise
898	untouched. That means that requests that currently execute will not be	1170	untouched (with the exception of readdir). That means that requests that
899	stopped and resources held by the request will not be freed prematurely.	1171	currently execute will not be stopped and resources held by the request
		1172	will not be freed prematurely.
900		1173
901	=item cb $req $callback->(...)	1174	=item cb $req $callback->(...)
902		1175
903	Replace (or simply set) the callback registered to the request.	1176	Replace (or simply set) the callback registered to the request.
904		1177
…		…
955	Their lifetime, simplified, looks like this: when they are empty, they	1228	Their lifetime, simplified, looks like this: when they are empty, they
956	will finish very quickly. If they contain only requests that are in the	1229	will finish very quickly. If they contain only requests that are in the
957	C<done> state, they will also finish. Otherwise they will continue to	1230	C<done> state, they will also finish. Otherwise they will continue to
958	exist.	1231	exist.
959		1232
960	That means after creating a group you have some time to add requests. And	1233	That means after creating a group you have some time to add requests
961	in the callbacks of those requests, you can add further requests to the	1234	(precisely before the callback has been invoked, which is only done within
962	group. And only when all those requests have finished will the the group	1235	the C<poll_cb>). And in the callbacks of those requests, you can add
963	itself finish.	1236	further requests to the group. And only when all those requests have
		1237	finished will the the group itself finish.
964		1238
965	=over 4	1239	=over 4
966		1240
967	=item add $grp ...	1241	=item add $grp ...
968		1242
…		…
977	=item $grp->cancel_subs	1251	=item $grp->cancel_subs
978		1252
979	Cancel all subrequests and clears any feeder, but not the group request	1253	Cancel all subrequests and clears any feeder, but not the group request
980	itself. Useful when you queued a lot of events but got a result early.	1254	itself. Useful when you queued a lot of events but got a result early.
981		1255
		1256	The group request will finish normally (you cannot add requests to the
		1257	group).
		1258
982	=item $grp->result (...)	1259	=item $grp->result (...)
983		1260
984	Set the result value(s) that will be passed to the group callback when all	1261	Set the result value(s) that will be passed to the group callback when all
985	subrequests have finished and set thre groups errno to the current value	1262	subrequests have finished and set the groups errno to the current value
986	of errno (just like calling C<errno> without an error number). By default,	1263	of errno (just like calling C<errno> without an error number). By default,
987	no argument will be passed and errno is zero.	1264	no argument will be passed and errno is zero.
988		1265
989	=item $grp->errno ([$errno])	1266	=item $grp->errno ([$errno])
990		1267
…		…
1001	=item feed $grp $callback->($grp)	1278	=item feed $grp $callback->($grp)
1002		1279
1003	Sets a feeder/generator on this group: every group can have an attached	1280	Sets a feeder/generator on this group: every group can have an attached
1004	generator that generates requests if idle. The idea behind this is that,	1281	generator that generates requests if idle. The idea behind this is that,
1005	although you could just queue as many requests as you want in a group,	1282	although you could just queue as many requests as you want in a group,
1006	this might starve other requests for a potentially long time. For	1283	this might starve other requests for a potentially long time. For example,
1007	example, C<aio_scandir> might generate hundreds of thousands C<aio_stat>	1284	C<aio_scandir> might generate hundreds of thousands C<aio_stat> requests,
1008	requests, delaying any later requests for a long time.	1285	delaying any later requests for a long time.
1009		1286
1010	To avoid this, and allow incremental generation of requests, you can	1287	To avoid this, and allow incremental generation of requests, you can
1011	instead a group and set a feeder on it that generates those requests. The	1288	instead a group and set a feeder on it that generates those requests. The
1012	feed callback will be called whenever there are few enough (see C<limit>,	1289	feed callback will be called whenever there are few enough (see C<limit>,
1013	below) requests active in the group itself and is expected to queue more	1290	below) requests active in the group itself and is expected to queue more
…		…
1017	not impose any limits).	1294	not impose any limits).
1018		1295
1019	If the feed does not queue more requests when called, it will be	1296	If the feed does not queue more requests when called, it will be
1020	automatically removed from the group.	1297	automatically removed from the group.
1021		1298
1022	If the feed limit is C<0>, it will be set to C<2> automatically.	1299	If the feed limit is C<0> when this method is called, it will be set to
		1300	C<2> automatically.
1023		1301
1024	Example:	1302	Example:
1025		1303
1026	# stat all files in @files, but only ever use four aio requests concurrently:	1304	# stat all files in @files, but only ever use four aio requests concurrently:
1027		1305
…		…
1039	Sets the feeder limit for the group: The feeder will be called whenever	1317	Sets the feeder limit for the group: The feeder will be called whenever
1040	the group contains less than this many requests.	1318	the group contains less than this many requests.
1041		1319
1042	Setting the limit to C<0> will pause the feeding process.	1320	Setting the limit to C<0> will pause the feeding process.
1043		1321
		1322	The default value for the limit is C<0>, but note that setting a feeder
		1323	automatically bumps it up to C<2>.
		1324
1044	=back	1325	=back
1045		1326
1046	=head2 SUPPORT FUNCTIONS	1327	=head2 SUPPORT FUNCTIONS
1047		1328
1048	=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION	1329	=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION
…		…
1050	=over 4	1331	=over 4
1051		1332
1052	=item $fileno = IO::AIO::poll_fileno	1333	=item $fileno = IO::AIO::poll_fileno
1053		1334
1054	Return the I<request result pipe file descriptor>. This filehandle must be	1335	Return the I<request result pipe file descriptor>. This filehandle must be
1055	polled for reading by some mechanism outside this module (e.g. Event or	1336	polled for reading by some mechanism outside this module (e.g. EV, Glib,
1056	select, see below or the SYNOPSIS). If the pipe becomes readable you have	1337	select and so on, see below or the SYNOPSIS). If the pipe becomes readable
1057	to call C<poll_cb> to check the results.	1338	you have to call C<poll_cb> to check the results.
1058		1339
1059	See C<poll_cb> for an example.	1340	See C<poll_cb> for an example.
1060		1341
1061	=item IO::AIO::poll_cb	1342	=item IO::AIO::poll_cb
1062		1343
1063	Process some outstanding events on the result pipe. You have to call this	1344	Process some outstanding events on the result pipe. You have to call this
1064	regularly. Returns the number of events processed. Returns immediately	1345	regularly. Returns C<0> if all events could be processed, or C<-1> if it
		1346	returned earlier for whatever reason. Returns immediately when no events
1065	when no events are outstanding. The amount of events processed depends on	1347	are outstanding. The amount of events processed depends on the settings of
1066	the settings of C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>.	1348	C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>.
1067		1349
1068	If not all requests were processed for whatever reason, the filehandle	1350	If not all requests were processed for whatever reason, the filehandle
1069	will still be ready when C<poll_cb> returns.	1351	will still be ready when C<poll_cb> returns, so normally you don't have to
		1352	do anything special to have it called later.
1070		1353
1071	Example: Install an Event watcher that automatically calls	1354	Example: Install an Event watcher that automatically calls
1072	IO::AIO::poll_cb with high priority:	1355	IO::AIO::poll_cb with high priority (more examples can be found in the
		1356	SYNOPSIS section, at the top of this document):
1073		1357
1074	Event->io (fd => IO::AIO::poll_fileno,	1358	Event->io (fd => IO::AIO::poll_fileno,
1075	poll => 'r', async => 1,	1359	poll => 'r', async => 1,
1076	cb => \&IO::AIO::poll_cb);	1360	cb => \&IO::AIO::poll_cb);
		1361
		1362	=item IO::AIO::poll_wait
		1363
		1364	If there are any outstanding requests and none of them in the result
		1365	phase, wait till the result filehandle becomes ready for reading (simply
		1366	does a C<select> on the filehandle. This is useful if you want to
		1367	synchronously wait for some requests to finish).
		1368
		1369	See C<nreqs> for an example.
		1370
		1371	=item IO::AIO::poll
		1372
		1373	Waits until some requests have been handled.
		1374
		1375	Returns the number of requests processed, but is otherwise strictly
		1376	equivalent to:
		1377
		1378	IO::AIO::poll_wait, IO::AIO::poll_cb
		1379
		1380	=item IO::AIO::flush
		1381
		1382	Wait till all outstanding AIO requests have been handled.
		1383
		1384	Strictly equivalent to:
		1385
		1386	IO::AIO::poll_wait, IO::AIO::poll_cb
		1387	while IO::AIO::nreqs;
1077		1388
1078	=item IO::AIO::max_poll_reqs $nreqs	1389	=item IO::AIO::max_poll_reqs $nreqs
1079		1390
1080	=item IO::AIO::max_poll_time $seconds	1391	=item IO::AIO::max_poll_time $seconds
1081		1392
…		…
1106	# use a low priority so other tasks have priority	1417	# use a low priority so other tasks have priority
1107	Event->io (fd => IO::AIO::poll_fileno,	1418	Event->io (fd => IO::AIO::poll_fileno,
1108	poll => 'r', nice => 1,	1419	poll => 'r', nice => 1,
1109	cb => &IO::AIO::poll_cb);	1420	cb => &IO::AIO::poll_cb);
1110		1421
1111	=item IO::AIO::poll_wait
1112
1113	If there are any outstanding requests and none of them in the result
1114	phase, wait till the result filehandle becomes ready for reading (simply
1115	does a C<select> on the filehandle. This is useful if you want to
1116	synchronously wait for some requests to finish).
1117
1118	See C<nreqs> for an example.
1119
1120	=item IO::AIO::poll
1121
1122	Waits until some requests have been handled.
1123
1124	Returns the number of requests processed, but is otherwise strictly
1125	equivalent to:
1126
1127	IO::AIO::poll_wait, IO::AIO::poll_cb
1128
1129	=item IO::AIO::flush
1130
1131	Wait till all outstanding AIO requests have been handled.
1132
1133	Strictly equivalent to:
1134
1135	IO::AIO::poll_wait, IO::AIO::poll_cb
1136	while IO::AIO::nreqs;
1137
1138	=back	1422	=back
1139		1423
1140	=head3 CONTROLLING THE NUMBER OF THREADS	1424	=head3 CONTROLLING THE NUMBER OF THREADS
1141		1425
1142	=over	1426	=over
…		…
1188		1472
1189	The default is probably ok in most situations, especially if thread	1473	The default is probably ok in most situations, especially if thread
1190	creation is fast. If thread creation is very slow on your system you might	1474	creation is fast. If thread creation is very slow on your system you might
1191	want to use larger values.	1475	want to use larger values.
1192		1476
1193	=item $oldmaxreqs = IO::AIO::max_outstanding $maxreqs	1477	=item IO::AIO::max_outstanding $maxreqs
1194		1478
1195	This is a very bad function to use in interactive programs because it	1479	This is a very bad function to use in interactive programs because it
1196	blocks, and a bad way to reduce concurrency because it is inexact: Better	1480	blocks, and a bad way to reduce concurrency because it is inexact: Better
1197	use an C<aio_group> together with a feed callback.	1481	use an C<aio_group> together with a feed callback.
1198		1482
1199	Sets the maximum number of outstanding requests to C<$nreqs>. If you	1483	Sets the maximum number of outstanding requests to C<$nreqs>. If you
1200	to queue up more than this number of requests, the next call to the	1484	do queue up more than this number of requests, the next call to the
1201	C<poll_cb> (and C<poll_some> and other functions calling C<poll_cb>)	1485	C<poll_cb> (and C<poll_some> and other functions calling C<poll_cb>)
1202	function will block until the limit is no longer exceeded.	1486	function will block until the limit is no longer exceeded.
1203		1487
1204	The default value is very large, so there is no practical limit on the	1488	The default value is very large, so there is no practical limit on the
1205	number of outstanding requests.	1489	number of outstanding requests.
1206		1490
1207	You can still queue as many requests as you want. Therefore,	1491	You can still queue as many requests as you want. Therefore,
1208	C<max_oustsanding> is mainly useful in simple scripts (with low values) or	1492	C<max_outstanding> is mainly useful in simple scripts (with low values) or
1209	as a stop gap to shield against fatal memory overflow (with large values).	1493	as a stop gap to shield against fatal memory overflow (with large values).
1210		1494
1211	=back	1495	=back
1212		1496
1213	=head3 STATISTICAL INFORMATION	1497	=head3 STATISTICAL INFORMATION
…		…
1234	Returns the number of requests currently in the pending state (executed,	1518	Returns the number of requests currently in the pending state (executed,
1235	but not yet processed by poll_cb).	1519	but not yet processed by poll_cb).
1236		1520
1237	=back	1521	=back
1238		1522
		1523	=head3 MISCELLANEOUS FUNCTIONS
		1524
		1525	IO::AIO implements some functions that might be useful, but are not
		1526	asynchronous.
		1527
		1528	=over 4
		1529
		1530	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
		1531
		1532	Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>,
		1533	but is blocking (this makes most sense if you know the input data is
		1534	likely cached already and the output filehandle is set to non-blocking
		1535	operations).
		1536
		1537	Returns the number of bytes copied, or C<-1> on error.
		1538
		1539	=item IO::AIO::fadvise $fh, $offset, $len, $advice
		1540
		1541	Simply calls the C<posix_fadvise> function (see it's
		1542	manpage for details). The following advice constants are
		1543	avaiable: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>,
		1544	C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>,
		1545	C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>.
		1546
		1547	On systems that do not implement C<posix_fadvise>, this function returns
		1548	ENOSYS, otherwise the return value of C<posix_fadvise>.
		1549
		1550	=item IO::AIO::mlockall $flags
		1551
		1552	Calls the C<mlockall> function with the given C<$flags> (a combination of
		1553	C<IO::AIO::MCL_CURRENT> and C<IO::AIO::MCL__FUTURE>).
		1554
		1555	On systems that do not implement C<mlockall>, this function returns
		1556	ENOSYS, otherwise the return value of C<mlockall>.
		1557
		1558	=item IO::AIO::munlockall
		1559
		1560	Calls the C<munlockall> function.
		1561
		1562	On systems that do not implement C<munlockall>, this function returns
		1563	ENOSYS, otherwise the return value of C<munlockall>.
		1564
		1565	=back
		1566
1239	=cut	1567	=cut
1240		1568
1241	# support function to convert a fd into a perl filehandle
1242	sub _fd2fh {
1243	return undef if $_[0] < 0;
1244
1245	# try to generate nice filehandles
1246	my $sym = "IO::AIO::fd#$_[0]";
1247	local *$sym;
1248
1249	open *$sym, "+<&=$_[0]" # usually works under any unix
1250	or open *$sym, "<&=$_[0]" # cygwin needs this
1251	or open *$sym, ">&=$_[0]" # or this
1252	or return undef;
1253
1254	*$sym
1255	}
1256
1257	min_parallel 8;	1569	min_parallel 8;
1258		1570
1259	END { flush }	1571	END { flush }
1260		1572
1261	1;	1573	1;
		1574
		1575	=head1 EVENT LOOP INTEGRATION
		1576
		1577	It is recommended to use L<AnyEvent::AIO> to integrate IO::AIO
		1578	automatically into many event loops:
		1579
		1580	# AnyEvent integration (EV, Event, Glib, Tk, POE, urxvt, pureperl...)
		1581	use AnyEvent::AIO;
		1582
		1583	You can also integrate IO::AIO manually into many event loops, here are
		1584	some examples of how to do this:
		1585
		1586	# EV integration
		1587	my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
		1588
		1589	# Event integration
		1590	Event->io (fd => IO::AIO::poll_fileno,
		1591	poll => 'r',
		1592	cb => \&IO::AIO::poll_cb);
		1593
		1594	# Glib/Gtk2 integration
		1595	add_watch Glib::IO IO::AIO::poll_fileno,
		1596	in => sub { IO::AIO::poll_cb; 1 };
		1597
		1598	# Tk integration
		1599	Tk::Event::IO->fileevent (IO::AIO::poll_fileno, "",
		1600	readable => \&IO::AIO::poll_cb);
		1601
		1602	# Danga::Socket integration
		1603	Danga::Socket->AddOtherFds (IO::AIO::poll_fileno =>
		1604	\&IO::AIO::poll_cb);
1262		1605
1263	=head2 FORK BEHAVIOUR	1606	=head2 FORK BEHAVIOUR
1264		1607
1265	This module should do "the right thing" when the process using it forks:	1608	This module should do "the right thing" when the process using it forks:
1266		1609
…		…
1284	bytes of memory. In addition, stat requests need a stat buffer (possibly	1627	bytes of memory. In addition, stat requests need a stat buffer (possibly
1285	a few hundred bytes), readdir requires a result buffer and so on. Perl	1628	a few hundred bytes), readdir requires a result buffer and so on. Perl
1286	scalars and other data passed into aio requests will also be locked and	1629	scalars and other data passed into aio requests will also be locked and
1287	will consume memory till the request has entered the done state.	1630	will consume memory till the request has entered the done state.
1288		1631
1289	This is now awfully much, so queuing lots of requests is not usually a	1632	This is not awfully much, so queuing lots of requests is not usually a
1290	problem.	1633	problem.
1291		1634
1292	Per-thread usage:	1635	Per-thread usage:
1293		1636
1294	In the execution phase, some aio requests require more memory for	1637	In the execution phase, some aio requests require more memory for
…		…
1299		1642
1300	Known bugs will be fixed in the next release.	1643	Known bugs will be fixed in the next release.
1301		1644
1302	=head1 SEE ALSO	1645	=head1 SEE ALSO
1303		1646
1304	L<Coro::AIO>.	1647	L<AnyEvent::AIO> for easy integration into event loops, L<Coro::AIO> for a
		1648	more natural syntax.
1305		1649
1306	=head1 AUTHOR	1650	=head1 AUTHOR
1307		1651
1308	Marc Lehmann <schmorp@schmorp.de>	1652	Marc Lehmann <schmorp@schmorp.de>
1309	http://home.schmorp.de/	1653	http://home.schmorp.de/

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Comparing IO-AIO/AIO.pm (file contents): Revision 1.108 by root, Fri Jun 1 13:25:50 2007 UTC vs. Revision 1.175 by root, Sun Jan 10 20:37:33 2010 UTC

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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.108 by root, Fri Jun 1 13:25:50 2007 UTC vs.
Revision 1.175 by root, Sun Jan 10 20:37:33 2010 UTC