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

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.211 by root, Tue Sep 27 12:10:29 2011 UTC vs.
Revision 1.278 by root, Sun Oct 1 07:24:34 2017 UTC

…		…
1	=head1 NAME	1	=head1 NAME
2		2
3	IO::AIO - Asynchronous Input/Output	3	IO::AIO - Asynchronous/Advanced Input/Output
4		4
5	=head1 SYNOPSIS	5	=head1 SYNOPSIS
6		6
7	use IO::AIO;	7	use IO::AIO;
8		8
58	not well-supported or restricted (GNU/Linux doesn't allow them on normal	58	not well-supported or restricted (GNU/Linux doesn't allow them on normal
59	files currently, for example), and they would only support aio_read and	59	files currently, for example), and they would only support aio_read and
60	aio_write, so the remaining functionality would have to be implemented	60	aio_write, so the remaining functionality would have to be implemented
61	using threads anyway.	61	using threads anyway.
62		62
		63	In addition to asynchronous I/O, this module also exports some rather
		64	arcane interfaces, such as C<madvise> or linux's C<splice> system call,
		65	which is why the C<A> in C<AIO> can also mean I<advanced>.
		66
63	Although the module will work in the presence of other (Perl-) threads,	67	Although the module will work in the presence of other (Perl-) threads,
64	it is currently not reentrant in any way, so use appropriate locking	68	it is currently not reentrant in any way, so use appropriate locking
65	yourself, always call C<poll_cb> from within the same thread, or never	69	yourself, always call C<poll_cb> from within the same thread, or never
66	call C<poll_cb> (or other C<aio_> functions) recursively.	70	call C<poll_cb> (or other C<aio_> functions) recursively.
67		71
68	=head2 EXAMPLE	72	=head2 EXAMPLE
69		73
70	This is a simple example that uses the EV module and loads	74	This is a simple example that uses the EV module and loads
71	F</etc/passwd> asynchronously:	75	F</etc/passwd> asynchronously:
72		76
73	use Fcntl;
74	use EV;	77	use EV;
75	use IO::AIO;	78	use IO::AIO;
76		79
77	# register the IO::AIO callback with EV	80	# register the IO::AIO callback with EV
78	my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;	81	my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
…		…
95		98
96	# file contents now in $contents	99	# file contents now in $contents
97	print $contents;	100	print $contents;
98		101
99	# exit event loop and program	102	# exit event loop and program
100	EV::unloop;	103	EV::break;
101	};	104	};
102	};	105	};
103		106
104	# possibly queue up other requests, or open GUI windows,	107	# possibly queue up other requests, or open GUI windows,
105	# check for sockets etc. etc.	108	# check for sockets etc. etc.
106		109
107	# process events as long as there are some:	110	# process events as long as there are some:
108	EV::loop;	111	EV::run;
109		112
110	=head1 REQUEST ANATOMY AND LIFETIME	113	=head1 REQUEST ANATOMY AND LIFETIME
111		114
112	Every C<aio_*> function creates a request. which is a C data structure not	115	Every C<aio_*> function creates a request. which is a C data structure not
113	directly visible to Perl.	116	directly visible to Perl.
…		…
168	use common::sense;	171	use common::sense;
169		172
170	use base 'Exporter';	173	use base 'Exporter';
171		174
172	BEGIN {	175	BEGIN {
173	our $VERSION = '4.0';	176	our $VERSION = 4.35;
174		177
175	our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close	178	our @AIO_REQ = qw(aio_sendfile aio_seek aio_read aio_write aio_open aio_close
176	aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx	179	aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx
177	aio_scandir aio_symlink aio_readlink aio_realpath aio_sync	180	aio_scandir aio_symlink aio_readlink aio_realpath aio_fcntl aio_ioctl
178	aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range aio_fallocate	181	aio_sync aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range
179	aio_pathsync aio_readahead	182	aio_pathsync aio_readahead aio_fiemap aio_allocate
180	aio_rename aio_link aio_move aio_copy aio_group	183	aio_rename aio_rename2 aio_link aio_move aio_copy aio_group
181	aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown	184	aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown
182	aio_chmod aio_utime aio_truncate	185	aio_chmod aio_utime aio_truncate
183	aio_msync aio_mtouch aio_mlock aio_mlockall	186	aio_msync aio_mtouch aio_mlock aio_mlockall
184	aio_statvfs	187	aio_statvfs
185	aio_wd);	188	aio_wd);
…		…
202		205
203	=head1 FUNCTIONS	206	=head1 FUNCTIONS
204		207
205	=head2 QUICK OVERVIEW	208	=head2 QUICK OVERVIEW
206		209
207	This section simply lists the prototypes of the most important functions	210	This section simply lists the prototypes most of the functions for
208	for quick reference. See the following sections for function-by-function	211	quick reference. See the following sections for function-by-function
209	documentation.	212	documentation.
210		213
211	aio_wd $pathname, $callback->($wd)	214	aio_wd $pathname, $callback->($wd)
212	aio_open $pathname, $flags, $mode, $callback->($fh)	215	aio_open $pathname, $flags, $mode, $callback->($fh)
213	aio_close $fh, $callback->($status)	216	aio_close $fh, $callback->($status)
		217	aio_seek $fh,$offset,$whence, $callback->($offs)
214	aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	218	aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
215	aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	219	aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
216	aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)	220	aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
217	aio_readahead $fh,$offset,$length, $callback->($retval)	221	aio_readahead $fh,$offset,$length, $callback->($retval)
218	aio_stat $fh_or_path, $callback->($status)	222	aio_stat $fh_or_path, $callback->($status)
219	aio_lstat $fh, $callback->($status)	223	aio_lstat $fh, $callback->($status)
220	aio_statvfs $fh_or_path, $callback->($statvfs)	224	aio_statvfs $fh_or_path, $callback->($statvfs)
221	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	225	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
222	aio_chown $fh_or_path, $uid, $gid, $callback->($status)	226	aio_chown $fh_or_path, $uid, $gid, $callback->($status)
		227	aio_chmod $fh_or_path, $mode, $callback->($status)
223	aio_truncate $fh_or_path, $offset, $callback->($status)	228	aio_truncate $fh_or_path, $offset, $callback->($status)
224	aio_chmod $fh_or_path, $mode, $callback->($status)	229	aio_allocate $fh, $mode, $offset, $len, $callback->($status)
		230	aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
225	aio_unlink $pathname, $callback->($status)	231	aio_unlink $pathname, $callback->($status)
226	aio_mknod $pathname, $mode, $dev, $callback->($status)	232	aio_mknod $pathname, $mode, $dev, $callback->($status)
227	aio_link $srcpath, $dstpath, $callback->($status)	233	aio_link $srcpath, $dstpath, $callback->($status)
228	aio_symlink $srcpath, $dstpath, $callback->($status)	234	aio_symlink $srcpath, $dstpath, $callback->($status)
229	aio_readlink $pathname, $callback->($link)	235	aio_readlink $pathname, $callback->($link)
230	aio_realpath $pathname, $callback->($link)	236	aio_realpath $pathname, $callback->($path)
231	aio_rename $srcpath, $dstpath, $callback->($status)	237	aio_rename $srcpath, $dstpath, $callback->($status)
		238	aio_rename2 $srcpath, $dstpath, $flags, $callback->($status)
232	aio_mkdir $pathname, $mode, $callback->($status)	239	aio_mkdir $pathname, $mode, $callback->($status)
233	aio_rmdir $pathname, $callback->($status)	240	aio_rmdir $pathname, $callback->($status)
234	aio_readdir $pathname, $callback->($entries)	241	aio_readdir $pathname, $callback->($entries)
235	aio_readdirx $pathname, $flags, $callback->($entries, $flags)	242	aio_readdirx $pathname, $flags, $callback->($entries, $flags)
236	IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST	243	IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST
237	IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN	244	IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN
		245	aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
238	aio_load $pathname, $data, $callback->($status)	246	aio_load $pathname, $data, $callback->($status)
239	aio_copy $srcpath, $dstpath, $callback->($status)	247	aio_copy $srcpath, $dstpath, $callback->($status)
240	aio_move $srcpath, $dstpath, $callback->($status)	248	aio_move $srcpath, $dstpath, $callback->($status)
241	aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
242	aio_rmtree $pathname, $callback->($status)	249	aio_rmtree $pathname, $callback->($status)
		250	aio_fcntl $fh, $cmd, $arg, $callback->($status)
		251	aio_ioctl $fh, $request, $buf, $callback->($status)
243	aio_sync $callback->($status)	252	aio_sync $callback->($status)
244	aio_syncfs $fh, $callback->($status)	253	aio_syncfs $fh, $callback->($status)
245	aio_fsync $fh, $callback->($status)	254	aio_fsync $fh, $callback->($status)
246	aio_fdatasync $fh, $callback->($status)	255	aio_fdatasync $fh, $callback->($status)
247	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)	256	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
248	aio_pathsync $pathname, $callback->($status)	257	aio_pathsync $pathname, $callback->($status)
249	aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	258	aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status)
250	aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	259	aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
251	aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)	260	aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
252	aio_mlockall $flags, $callback->($status)	261	aio_mlockall $flags, $callback->($status)
253	aio_group $callback->(...)	262	aio_group $callback->(...)
254	aio_nop $callback->()	263	aio_nop $callback->()
…		…
268	IO::AIO::idle_timeout $seconds	277	IO::AIO::idle_timeout $seconds
269	IO::AIO::max_outstanding $maxreqs	278	IO::AIO::max_outstanding $maxreqs
270	IO::AIO::nreqs	279	IO::AIO::nreqs
271	IO::AIO::nready	280	IO::AIO::nready
272	IO::AIO::npending	281	IO::AIO::npending
		282	$nfd = IO::AIO::get_fdlimit [EXPERIMENTAL]
		283	IO::AIO::min_fdlimit $nfd [EXPERIMENTAL]
273		284
274	IO::AIO::sendfile $ofh, $ifh, $offset, $count	285	IO::AIO::sendfile $ofh, $ifh, $offset, $count
275	IO::AIO::fadvise $fh, $offset, $len, $advice	286	IO::AIO::fadvise $fh, $offset, $len, $advice
		287	IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]]
		288	IO::AIO::munmap $scalar
276	IO::AIO::madvise $scalar, $offset, $length, $advice	289	IO::AIO::madvise $scalar, $offset, $length, $advice
277	IO::AIO::mprotect $scalar, $offset, $length, $protect	290	IO::AIO::mprotect $scalar, $offset, $length, $protect
278	IO::AIO::munlock $scalar, $offset = 0, $length = undef	291	IO::AIO::munlock $scalar, $offset = 0, $length = undef
279	IO::AIO::munlockall	292	IO::AIO::munlockall
280		293
281	=head2 AIO REQUEST FUNCTIONS	294	=head2 API NOTES
282		295
283	All the C<aio_*> calls are more or less thin wrappers around the syscall	296	All the C<aio_*> calls are more or less thin wrappers around the syscall
284	with the same name (sans C<aio_>). The arguments are similar or identical,	297	with the same name (sans C<aio_>). The arguments are similar or identical,
285	and they all accept an additional (and optional) C<$callback> argument	298	and they all accept an additional (and optional) C<$callback> argument
286	which must be a code reference. This code reference will get called with	299	which must be a code reference. This code reference will be called after
287	the syscall return code (e.g. most syscalls return C<-1> on error, unlike	300	the syscall has been executed in an asynchronous fashion. The results
288	perl, which usually delivers "false") as its sole argument after the given	301	of the request will be passed as arguments to the callback (and, if an
289	syscall has been executed asynchronously.	302	error occured, in C<$!>) - for most requests the syscall return code (e.g.
		303	most syscalls return C<-1> on error, unlike perl, which usually delivers
		304	"false").
		305
		306	Some requests (such as C<aio_readdir>) pass the actual results and
		307	communicate failures by passing C<undef>.
290		308
291	All functions expecting a filehandle keep a copy of the filehandle	309	All functions expecting a filehandle keep a copy of the filehandle
292	internally until the request has finished.	310	internally until the request has finished.
293		311
294	All functions return request objects of type L<IO::AIO::REQ> that allow	312	All functions return request objects of type L<IO::AIO::REQ> that allow
295	further manipulation of those requests while they are in-flight.	313	further manipulation of those requests while they are in-flight.
296		314
297	The pathnames you pass to these routines I<should> be absolute. The	315	The pathnames you pass to these routines I<should> be absolute. The
298	reason for this is that at the time the request is being executed, the	316	reason for this is that at the time the request is being executed, the
299	current working directory could have changed. Alternatively, you can make	317	current working directory could have changed. Alternatively, you can
300	sure that you never change the current working directory anywhere in	318	make sure that you never change the current working directory anywhere
301	the program and then use relative paths. Lastly, you can take advantage	319	in the program and then use relative paths. You can also take advantage
302	of IO::AIOs working directory abstraction - see the description of the	320	of IO::AIOs working directory abstraction, that lets you specify paths
		321	relative to some previously-opened "working directory object" - see the
303	C<IO::AIO::WD> class later in this document.	322	description of the C<IO::AIO::WD> class later in this document.
304		323
305	To encode pathnames as octets, either make sure you either: a) always pass	324	To encode pathnames as octets, either make sure you either: a) always pass
306	in filenames you got from outside (command line, readdir etc.) without	325	in filenames you got from outside (command line, readdir etc.) without
307	tinkering, b) are ASCII or ISO 8859-1, c) use the Encode module and encode	326	tinkering, b) are in your native filesystem encoding, c) use the Encode
308	your pathnames to the locale (or other) encoding in effect in the user	327	module and encode your pathnames to the locale (or other) encoding in
309	environment, d) use Glib::filename_from_unicode on unicode filenames or e)	328	effect in the user environment, d) use Glib::filename_from_unicode on
310	use something else to ensure your scalar has the correct contents.	329	unicode filenames or e) use something else to ensure your scalar has the
		330	correct contents.
311		331
312	This works, btw. independent of the internal UTF-8 bit, which IO::AIO	332	This works, btw. independent of the internal UTF-8 bit, which IO::AIO
313	handles correctly whether it is set or not.	333	handles correctly whether it is set or not.
		334
		335	=head2 AIO REQUEST FUNCTIONS
314		336
315	=over 4	337	=over 4
316		338
317	=item $prev_pri = aioreq_pri [$pri]	339	=item $prev_pri = aioreq_pri [$pri]
318		340
…		…
348		370
349		371
350	=item aio_open $pathname, $flags, $mode, $callback->($fh)	372	=item aio_open $pathname, $flags, $mode, $callback->($fh)
351		373
352	Asynchronously open or create a file and call the callback with a newly	374	Asynchronously open or create a file and call the callback with a newly
353	created filehandle for the file.	375	created filehandle for the file (or C<undef> in case of an error).
354		376
355	The pathname passed to C<aio_open> must be absolute. See API NOTES, above,	377	The pathname passed to C<aio_open> must be absolute. See API NOTES, above,
356	for an explanation.	378	for an explanation.
357		379
358	The C<$flags> argument is a bitmask. See the C<Fcntl> module for a	380	The C<$flags> argument is a bitmask. See the C<Fcntl> module for a
…		…
381	following POSIX and non-POSIX constants are available (missing ones on	403	following POSIX and non-POSIX constants are available (missing ones on
382	your system are, as usual, C<0>):	404	your system are, as usual, C<0>):
383		405
384	C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,	406	C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,
385	C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>,	407	C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>,
386	C<O_RSYNC>, C<O_SYNC> and C<O_TTY_INIT>.	408	C<O_RSYNC>, C<O_SYNC>, C<O_PATH>, C<O_TMPFILE>, and C<O_TTY_INIT>.
387		409
388		410
389	=item aio_close $fh, $callback->($status)	411	=item aio_close $fh, $callback->($status)
390		412
391	Asynchronously close a file and call the callback with the result	413	Asynchronously close a file and call the callback with the result
…		…
401	Or in other words: the file descriptor will be closed, but it will not be	423	Or in other words: the file descriptor will be closed, but it will not be
402	free for reuse until the perl filehandle is closed.	424	free for reuse until the perl filehandle is closed.
403		425
404	=cut	426	=cut
405		427
		428	=item aio_seek $fh, $offset, $whence, $callback->($offs)
		429
		430	Seeks the filehandle to the new C<$offset>, similarly to perl's
		431	C<sysseek>. The C<$whence> can use the traditional values (C<0> for
		432	C<IO::AIO::SEEK_SET>, C<1> for C<IO::AIO::SEEK_CUR> or C<2> for
		433	C<IO::AIO::SEEK_END>).
		434
		435	The resulting absolute offset will be passed to the callback, or C<-1> in
		436	case of an error.
		437
		438	In theory, the C<$whence> constants could be different than the
		439	corresponding values from L<Fcntl>, but perl guarantees they are the same,
		440	so don't panic.
		441
		442	As a GNU/Linux (and maybe Solaris) extension, also the constants
		443	C<IO::AIO::SEEK_DATA> and C<IO::AIO::SEEK_HOLE> are available, if they
		444	could be found. No guarantees about suitability for use in C<aio_seek> or
		445	Perl's C<sysseek> can be made though, although I would naively assume they
		446	"just work".
		447
406	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	448	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
407		449
408	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	450	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
409		451
410	Reads or writes C<$length> bytes from or to the specified C<$fh> and	452	Reads or writes C<$length> bytes from or to the specified C<$fh> and
411	C<$offset> into the scalar given by C<$data> and offset C<$dataoffset>	453	C<$offset> into the scalar given by C<$data> and offset C<$dataoffset> and
412	and calls the callback without the actual number of bytes read (or -1 on	454	calls the callback with the actual number of bytes transferred (or -1 on
413	error, just like the syscall).	455	error, just like the syscall).
414		456
415	C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to	457	C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to
416	offset plus the actual number of bytes read.	458	offset plus the actual number of bytes read.
417		459
…		…
475	As native sendfile syscalls (as practically any non-POSIX interface hacked	517	As native sendfile syscalls (as practically any non-POSIX interface hacked
476	together in a hurry to improve benchmark numbers) tend to be rather buggy	518	together in a hurry to improve benchmark numbers) tend to be rather buggy
477	on many systems, this implementation tries to work around some known bugs	519	on many systems, this implementation tries to work around some known bugs
478	in Linux and FreeBSD kernels (probably others, too), but that might fail,	520	in Linux and FreeBSD kernels (probably others, too), but that might fail,
479	so you really really should check the return value of C<aio_sendfile> -	521	so you really really should check the return value of C<aio_sendfile> -
480	fewre bytes than expected might have been transferred.	522	fewer bytes than expected might have been transferred.
481		523
482		524
483	=item aio_readahead $fh,$offset,$length, $callback->($retval)	525	=item aio_readahead $fh,$offset,$length, $callback->($retval)
484		526
485	C<aio_readahead> populates the page cache with data from a file so that	527	C<aio_readahead> populates the page cache with data from a file so that
…		…
489	whole pages, so that offset is effectively rounded down to a page boundary	531	whole pages, so that offset is effectively rounded down to a page boundary
490	and bytes are read up to the next page boundary greater than or equal to	532	and bytes are read up to the next page boundary greater than or equal to
491	(off-set+length). C<aio_readahead> does not read beyond the end of the	533	(off-set+length). C<aio_readahead> does not read beyond the end of the
492	file. The current file offset of the file is left unchanged.	534	file. The current file offset of the file is left unchanged.
493		535
494	If that syscall doesn't exist (likely if your OS isn't Linux) it will be	536	If that syscall doesn't exist (likely if your kernel isn't Linux) it will
495	emulated by simply reading the data, which would have a similar effect.	537	be emulated by simply reading the data, which would have a similar effect.
496		538
497		539
498	=item aio_stat $fh_or_path, $callback->($status)	540	=item aio_stat $fh_or_path, $callback->($status)
499		541
500	=item aio_lstat $fh, $callback->($status)	542	=item aio_lstat $fh, $callback->($status)
…		…
569	namemax => 255,	611	namemax => 255,
570	frsize => 1024,	612	frsize => 1024,
571	fsid => 1810	613	fsid => 1810
572	}	614	}
573		615
		616	Here is a (likely partial - send me updates!) list of fsid values used by
		617	Linux - it is safe to hardcode these when C<$^O> is C<linux>:
		618
		619	0x0000adf5 adfs
		620	0x0000adff affs
		621	0x5346414f afs
		622	0x09041934 anon-inode filesystem
		623	0x00000187 autofs
		624	0x42465331 befs
		625	0x1badface bfs
		626	0x42494e4d binfmt_misc
		627	0x9123683e btrfs
		628	0x0027e0eb cgroupfs
		629	0xff534d42 cifs
		630	0x73757245 coda
		631	0x012ff7b7 coh
		632	0x28cd3d45 cramfs
		633	0x453dcd28 cramfs-wend (wrong endianness)
		634	0x64626720 debugfs
		635	0x00001373 devfs
		636	0x00001cd1 devpts
		637	0x0000f15f ecryptfs
		638	0x00414a53 efs
		639	0x0000137d ext
		640	0x0000ef53 ext2/ext3/ext4
		641	0x0000ef51 ext2
		642	0xf2f52010 f2fs
		643	0x00004006 fat
		644	0x65735546 fuseblk
		645	0x65735543 fusectl
		646	0x0bad1dea futexfs
		647	0x01161970 gfs2
		648	0x47504653 gpfs
		649	0x00004244 hfs
		650	0xf995e849 hpfs
		651	0x00c0ffee hostfs
		652	0x958458f6 hugetlbfs
		653	0x2bad1dea inotifyfs
		654	0x00009660 isofs
		655	0x000072b6 jffs2
		656	0x3153464a jfs
		657	0x6b414653 k-afs
		658	0x0bd00bd0 lustre
		659	0x0000137f minix
		660	0x0000138f minix 30 char names
		661	0x00002468 minix v2
		662	0x00002478 minix v2 30 char names
		663	0x00004d5a minix v3
		664	0x19800202 mqueue
		665	0x00004d44 msdos
		666	0x0000564c novell
		667	0x00006969 nfs
		668	0x6e667364 nfsd
		669	0x00003434 nilfs
		670	0x5346544e ntfs
		671	0x00009fa1 openprom
		672	0x7461636F ocfs2
		673	0x00009fa0 proc
		674	0x6165676c pstorefs
		675	0x0000002f qnx4
		676	0x68191122 qnx6
		677	0x858458f6 ramfs
		678	0x52654973 reiserfs
		679	0x00007275 romfs
		680	0x67596969 rpc_pipefs
		681	0x73636673 securityfs
		682	0xf97cff8c selinux
		683	0x0000517b smb
		684	0x534f434b sockfs
		685	0x73717368 squashfs
		686	0x62656572 sysfs
		687	0x012ff7b6 sysv2
		688	0x012ff7b5 sysv4
		689	0x01021994 tmpfs
		690	0x15013346 udf
		691	0x00011954 ufs
		692	0x54190100 ufs byteswapped
		693	0x00009fa2 usbdevfs
		694	0x01021997 v9fs
		695	0xa501fcf5 vxfs
		696	0xabba1974 xenfs
		697	0x012ff7b4 xenix
		698	0x58465342 xfs
		699	0x012fd16d xia
574		700
575	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	701	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
576		702
577	Works like perl's C<utime> function (including the special case of $atime	703	Works like perl's C<utime> function (including the special case of $atime
578	and $mtime being undef). Fractional times are supported if the underlying	704	and $mtime being undef). Fractional times are supported if the underlying
…		…
606	=item aio_truncate $fh_or_path, $offset, $callback->($status)	732	=item aio_truncate $fh_or_path, $offset, $callback->($status)
607		733
608	Works like truncate(2) or ftruncate(2).	734	Works like truncate(2) or ftruncate(2).
609		735
610		736
		737	=item aio_allocate $fh, $mode, $offset, $len, $callback->($status)
		738
		739	Allocates or frees disk space according to the C<$mode> argument. See the
		740	linux C<fallocate> documentation for details.
		741
		742	C<$mode> is usually C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> to allocate
		743	space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE \| IO::AIO::FALLOC_FL_KEEP_SIZE>,
		744	to deallocate a file range.
		745
		746	IO::AIO also supports C<FALLOC_FL_COLLAPSE_RANGE>, to remove a range
		747	(without leaving a hole), C<FALLOC_FL_ZERO_RANGE>, to zero a range,
		748	C<FALLOC_FL_INSERT_RANGE> to insert a range and C<FALLOC_FL_UNSHARE_RANGE>
		749	to unshare shared blocks (see your L<fallocate(2)> manpage).
		750
		751	The file system block size used by C<fallocate> is presumably the
		752	C<f_bsize> returned by C<statvfs>, but different filesystems and filetypes
		753	can dictate other limitations.
		754
		755	If C<fallocate> isn't available or cannot be emulated (currently no
		756	emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>.
		757
		758
611	=item aio_chmod $fh_or_path, $mode, $callback->($status)	759	=item aio_chmod $fh_or_path, $mode, $callback->($status)
612		760
613	Works like perl's C<chmod> function.	761	Works like perl's C<chmod> function.
614		762
615		763
…		…
652		800
653		801
654	=item aio_realpath $pathname, $callback->($path)	802	=item aio_realpath $pathname, $callback->($path)
655		803
656	Asynchronously make the path absolute and resolve any symlinks in	804	Asynchronously make the path absolute and resolve any symlinks in
657	C<$path>. The resulting path only consists of directories (Same as	805	C<$path>. The resulting path only consists of directories (same as
658	L<Cwd::realpath>).	806	L<Cwd::realpath>).
659		807
660	This request can be used to get the absolute path of the current working	808	This request can be used to get the absolute path of the current working
661	directory by passing it a path of F<.> (a single dot).	809	directory by passing it a path of F<.> (a single dot).
662		810
663		811
664	=item aio_rename $srcpath, $dstpath, $callback->($status)	812	=item aio_rename $srcpath, $dstpath, $callback->($status)
665		813
666	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as	814	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as
667	rename(2) and call the callback with the result code.	815	rename(2) and call the callback with the result code.
		816
		817	On systems that support the AIO::WD working directory abstraction
		818	natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead
		819	of failing, C<rename> is called on the absolute path of C<$wd>.
		820
		821
		822	=item aio_rename2 $srcpath, $dstpath, $flags, $callback->($status)
		823
		824	Basically a version of C<aio_rename> with an additional C<$flags>
		825	argument. Calling this with C<$flags=0> is the same as calling
		826	C<aio_rename>.
		827
		828	Non-zero flags are currently only supported on GNU/Linux systems that
		829	support renameat2. Other systems fail with C<ENOSYS> in this case.
		830
		831	The following constants are available (missing ones are, as usual C<0>),
		832	see renameat2(2) for details:
		833
		834	C<IO::AIO::RENAME_NOREPLACE>, C<IO::AIO::RENAME_EXCHANGE>
		835	and C<IO::AIO::RENAME_WHITEOUT>.
668		836
669		837
670	=item aio_mkdir $pathname, $mode, $callback->($status)	838	=item aio_mkdir $pathname, $mode, $callback->($status)
671		839
672	Asynchronously mkdir (create) a directory and call the callback with	840	Asynchronously mkdir (create) a directory and call the callback with
…		…
676		844
677	=item aio_rmdir $pathname, $callback->($status)	845	=item aio_rmdir $pathname, $callback->($status)
678		846
679	Asynchronously rmdir (delete) a directory and call the callback with the	847	Asynchronously rmdir (delete) a directory and call the callback with the
680	result code.	848	result code.
		849
		850	On systems that support the AIO::WD working directory abstraction
		851	natively, the case C<[$wd, "."]> is specialcased - instead of failing,
		852	C<rmdir> is called on the absolute path of C<$wd>.
681		853
682		854
683	=item aio_readdir $pathname, $callback->($entries)	855	=item aio_readdir $pathname, $callback->($entries)
684		856
685	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire	857	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire
…		…
787	=item aio_copy $srcpath, $dstpath, $callback->($status)	959	=item aio_copy $srcpath, $dstpath, $callback->($status)
788		960
789	Try to copy the I<file> (directories not supported as either source or	961	Try to copy the I<file> (directories not supported as either source or
790	destination) from C<$srcpath> to C<$dstpath> and call the callback with	962	destination) from C<$srcpath> to C<$dstpath> and call the callback with
791	a status of C<0> (ok) or C<-1> (error, see C<$!>).	963	a status of C<0> (ok) or C<-1> (error, see C<$!>).
		964
		965	Existing destination files will be truncated.
792		966
793	This is a composite request that creates the destination file with	967	This is a composite request that creates the destination file with
794	mode 0200 and copies the contents of the source file into it using	968	mode 0200 and copies the contents of the source file into it using
795	C<aio_sendfile>, followed by restoring atime, mtime, access mode and	969	C<aio_sendfile>, followed by restoring atime, mtime, access mode and
796	uid/gid, in that order.	970	uid/gid, in that order.
…		…
906	Scans a directory (similar to C<aio_readdir>) but additionally tries to	1080	Scans a directory (similar to C<aio_readdir>) but additionally tries to
907	efficiently separate the entries of directory C<$path> into two sets of	1081	efficiently separate the entries of directory C<$path> into two sets of
908	names, directories you can recurse into (directories), and ones you cannot	1082	names, directories you can recurse into (directories), and ones you cannot
909	recurse into (everything else, including symlinks to directories).	1083	recurse into (everything else, including symlinks to directories).
910		1084
911	C<aio_scandir> is a composite request that creates of many sub requests_	1085	C<aio_scandir> is a composite request that generates many sub requests.
912	C<$maxreq> specifies the maximum number of outstanding aio requests that	1086	C<$maxreq> specifies the maximum number of outstanding aio requests that
913	this function generates. If it is C<< <= 0 >>, then a suitable default	1087	this function generates. If it is C<< <= 0 >>, then a suitable default
914	will be chosen (currently 4).	1088	will be chosen (currently 4).
915		1089
916	On error, the callback is called without arguments, otherwise it receives	1090	On error, the callback is called without arguments, otherwise it receives
…		…
967	my $grp = aio_group $cb;	1141	my $grp = aio_group $cb;
968		1142
969	$maxreq = 4 if $maxreq <= 0;	1143	$maxreq = 4 if $maxreq <= 0;
970		1144
971	# get a wd object	1145	# get a wd object
972
973	aioreq_pri $pri;	1146	aioreq_pri $pri;
974	add $grp aio_wd $path, sub {	1147	add $grp aio_wd $path, sub {
		1148	$_[0]
		1149	or return $grp->result ();
		1150
975	my $wd = [shift, "."];	1151	my $wd = [shift, "."];
976		1152
977	# stat once	1153	# stat once
978	aioreq_pri $pri;	1154	aioreq_pri $pri;
979	add $grp aio_stat $wd, sub {	1155	add $grp aio_stat $wd, sub {
…		…
1048	}	1224	}
1049		1225
1050	=item aio_rmtree $pathname, $callback->($status)	1226	=item aio_rmtree $pathname, $callback->($status)
1051		1227
1052	Delete a directory tree starting (and including) C<$path>, return the	1228	Delete a directory tree starting (and including) C<$path>, return the
1053	status of the final C<rmdir> only. This is a composite request that	1229	status of the final C<rmdir> only. This is a composite request that
1054	uses C<aio_scandir> to recurse into and rmdir directories, and unlink	1230	uses C<aio_scandir> to recurse into and rmdir directories, and unlink
1055	everything else.	1231	everything else.
1056		1232
1057	=cut	1233	=cut
1058		1234
…		…
1079	add $grp $dirgrp;	1255	add $grp $dirgrp;
1080	};	1256	};
1081		1257
1082	$grp	1258	$grp
1083	}	1259	}
		1260
		1261	=item aio_fcntl $fh, $cmd, $arg, $callback->($status)
		1262
		1263	=item aio_ioctl $fh, $request, $buf, $callback->($status)
		1264
		1265	These work just like the C<fcntl> and C<ioctl> built-in functions, except
		1266	they execute asynchronously and pass the return value to the callback.
		1267
		1268	Both calls can be used for a lot of things, some of which make more sense
		1269	to run asynchronously in their own thread, while some others make less
		1270	sense. For example, calls that block waiting for external events, such
		1271	as locking, will also lock down an I/O thread while it is waiting, which
		1272	can deadlock the whole I/O system. At the same time, there might be no
		1273	alternative to using a thread to wait.
		1274
		1275	So in general, you should only use these calls for things that do
		1276	(filesystem) I/O, not for things that wait for other events (network,
		1277	other processes), although if you are careful and know what you are doing,
		1278	you still can.
		1279
		1280	The following constants are available (missing ones are, as usual C<0>):
		1281
		1282	C<F_DUPFD_CLOEXEC>,
		1283
		1284	C<F_OFD_GETLK>, C<F_OFD_SETLK>, C<F_OFD_GETLKW>,
		1285
		1286	C<FIFREEZE>, C<FITHAW>, C<FITRIM>, C<FICLONE>, C<FICLONERANGE>, C<FIDEDUPERANGE>.
		1287
		1288	C<FS_IOC_GETFLAGS>, C<FS_IOC_SETFLAGS>, C<FS_IOC_GETVERSION>, C<FS_IOC_SETVERSION>,
		1289	C<FS_IOC_FIEMAP>.
		1290
		1291	C<FS_IOC_FSGETXATTR>, C<FS_IOC_FSSETXATTR>, C<FS_IOC_SET_ENCRYPTION_POLICY>,
		1292	C<FS_IOC_GET_ENCRYPTION_PWSALT>, C<FS_IOC_GET_ENCRYPTION_POLICY>, C<FS_KEY_DESCRIPTOR_SIZE>.
		1293
		1294	C<FS_SECRM_FL>, C<FS_UNRM_FL>, C<FS_COMPR_FL>, C<FS_SYNC_FL>, C<FS_IMMUTABLE_FL>,
		1295	C<FS_APPEND_FL>, C<FS_NODUMP_FL>, C<FS_NOATIME_FL>, C<FS_DIRTY_FL>,
		1296	C<FS_COMPRBLK_FL>, C<FS_NOCOMP_FL>, C<FS_ENCRYPT_FL>, C<FS_BTREE_FL>,
		1297	C<FS_INDEX_FL>, C<FS_JOURNAL_DATA_FL>, C<FS_NOTAIL_FL>, C<FS_DIRSYNC_FL>, C<FS_TOPDIR_FL>,
		1298	C<FS_FL_USER_MODIFIABLE>.
		1299
		1300	C<FS_XFLAG_REALTIME>, C<FS_XFLAG_PREALLOC>, C<FS_XFLAG_IMMUTABLE>, C<FS_XFLAG_APPEND>,
		1301	C<FS_XFLAG_SYNC>, C<FS_XFLAG_NOATIME>, C<FS_XFLAG_NODUMP>, C<FS_XFLAG_RTINHERIT>,
		1302	C<FS_XFLAG_PROJINHERIT>, C<FS_XFLAG_NOSYMLINKS>, C<FS_XFLAG_EXTSIZE>, C<FS_XFLAG_EXTSZINHERIT>,
		1303	C<FS_XFLAG_NODEFRAG>, C<FS_XFLAG_FILESTREAM>, C<FS_XFLAG_DAX>, C<FS_XFLAG_HASATTR>,
1084		1304
1085	=item aio_sync $callback->($status)	1305	=item aio_sync $callback->($status)
1086		1306
1087	Asynchronously call sync and call the callback when finished.	1307	Asynchronously call sync and call the callback when finished.
1088		1308
…		…
1157	};	1377	};
1158		1378
1159	$grp	1379	$grp
1160	}	1380	}
1161		1381
1162	=item aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	1382	=item aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status)
1163		1383
1164	This is a rather advanced IO::AIO call, which only works on mmap(2)ed	1384	This is a rather advanced IO::AIO call, which only works on mmap(2)ed
1165	scalars (see the C<IO::AIO::mmap> function, although it also works on data	1385	scalars (see the C<IO::AIO::mmap> function, although it also works on data
1166	scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the	1386	scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the
1167	scalar must only be modified in-place while an aio operation is pending on	1387	scalar must only be modified in-place while an aio operation is pending on
…		…
1169		1389
1170	It calls the C<msync> function of your OS, if available, with the memory	1390	It calls the C<msync> function of your OS, if available, with the memory
1171	area starting at C<$offset> in the string and ending C<$length> bytes	1391	area starting at C<$offset> in the string and ending C<$length> bytes
1172	later. If C<$length> is negative, counts from the end, and if C<$length>	1392	later. If C<$length> is negative, counts from the end, and if C<$length>
1173	is C<undef>, then it goes till the end of the string. The flags can be	1393	is C<undef>, then it goes till the end of the string. The flags can be
1174	a combination of C<IO::AIO::MS_ASYNC>, C<IO::AIO::MS_INVALIDATE> and	1394	either C<IO::AIO::MS_ASYNC> or C<IO::AIO::MS_SYNC>, plus an optional
1175	C<IO::AIO::MS_SYNC>.	1395	C<IO::AIO::MS_INVALIDATE>.
1176		1396
1177	=item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	1397	=item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
1178		1398
1179	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1399	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
1180	scalars.	1400	scalars.
1181		1401
1182	It touches (reads or writes) all memory pages in the specified	1402	It touches (reads or writes) all memory pages in the specified
1183	range inside the scalar. All caveats and parameters are the same	1403	range inside the scalar. All caveats and parameters are the same
1184	as for C<aio_msync>, above, except for flags, which must be either	1404	as for C<aio_msync>, above, except for flags, which must be either
1185	C<0> (which reads all pages and ensures they are instantiated) or	1405	C<0> (which reads all pages and ensures they are instantiated) or
1186	C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and	1406	C<IO::AIO::MT_MODIFY>, which modifies the memory pages (by reading and
1187	writing an octet from it, which dirties the page).	1407	writing an octet from it, which dirties the page).
1188		1408
1189	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)	1409	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
1190		1410
1191	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1411	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
…		…
1222	documented under L<MISCELLANEOUS FUNCTIONS>.	1442	documented under L<MISCELLANEOUS FUNCTIONS>.
1223		1443
1224	Example: asynchronously lock all current and future pages into memory.	1444	Example: asynchronously lock all current and future pages into memory.
1225		1445
1226	aio_mlockall IO::AIO::MCL_FUTURE;	1446	aio_mlockall IO::AIO::MCL_FUTURE;
		1447
		1448	=item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
		1449
		1450	Queries the extents of the given file (by calling the Linux C<FIEMAP>
		1451	ioctl, see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If
		1452	the ioctl is not available on your OS, then this request will fail with
		1453	C<ENOSYS>.
		1454
		1455	C<$start> is the starting offset to query extents for, C<$length> is the
		1456	size of the range to query - if it is C<undef>, then the whole file will
		1457	be queried.
		1458
		1459	C<$flags> is a combination of flags (C<IO::AIO::FIEMAP_FLAG_SYNC> or
		1460	C<IO::AIO::FIEMAP_FLAG_XATTR> - C<IO::AIO::FIEMAP_FLAGS_COMPAT> is also
		1461	exported), and is normally C<0> or C<IO::AIO::FIEMAP_FLAG_SYNC> to query
		1462	the data portion.
		1463
		1464	C<$count> is the maximum number of extent records to return. If it is
		1465	C<undef>, then IO::AIO queries all extents of the range. As a very special
		1466	case, if it is C<0>, then the callback receives the number of extents
		1467	instead of the extents themselves (which is unreliable, see below).
		1468
		1469	If an error occurs, the callback receives no arguments. The special
		1470	C<errno> value C<IO::AIO::EBADR> is available to test for flag errors.
		1471
		1472	Otherwise, the callback receives an array reference with extent
		1473	structures. Each extent structure is an array reference itself, with the
		1474	following members:
		1475
		1476	[$logical, $physical, $length, $flags]
		1477
		1478	Flags is any combination of the following flag values (typically either C<0>
		1479	or C<IO::AIO::FIEMAP_EXTENT_LAST> (1)):
		1480
		1481	C<IO::AIO::FIEMAP_EXTENT_LAST>, C<IO::AIO::FIEMAP_EXTENT_UNKNOWN>,
		1482	C<IO::AIO::FIEMAP_EXTENT_DELALLOC>, C<IO::AIO::FIEMAP_EXTENT_ENCODED>,
		1483	C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>,
		1484	C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>,
		1485	C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or
		1486	C<IO::AIO::FIEMAP_EXTENT_SHARED>.
		1487
		1488	At the time of this writing (Linux 3.2), this request is unreliable unless
		1489	C<$count> is C<undef>, as the kernel has all sorts of bugs preventing
		1490	it to return all extents of a range for files with a large number of
		1491	extents. The code (only) works around all these issues if C<$count> is
		1492	C<undef>.
1227		1493
1228	=item aio_group $callback->(...)	1494	=item aio_group $callback->(...)
1229		1495
1230	This is a very special aio request: Instead of doing something, it is a	1496	This is a very special aio request: Instead of doing something, it is a
1231	container for other aio requests, which is useful if you want to bundle	1497	container for other aio requests, which is useful if you want to bundle
…		…
1295	object. This object stores the canonicalised, absolute version of the	1561	object. This object stores the canonicalised, absolute version of the
1296	path, and on systems that allow it, also a directory file descriptor.	1562	path, and on systems that allow it, also a directory file descriptor.
1297		1563
1298	Everywhere where a pathname is accepted by IO::AIO (e.g. in C<aio_stat>	1564	Everywhere where a pathname is accepted by IO::AIO (e.g. in C<aio_stat>
1299	or C<aio_unlink>), one can specify an array reference with an IO::AIO::WD	1565	or C<aio_unlink>), one can specify an array reference with an IO::AIO::WD
1300	object and a pathname instead. If the pathname is absolute, the	1566	object and a pathname instead (or the IO::AIO::WD object alone, which
		1567	gets interpreted as C<[$wd, "."]>). If the pathname is absolute, the
1301	IO::AIO::WD objetc is ignored, otherwise the pathname is resolved relative	1568	IO::AIO::WD object is ignored, otherwise the pathname is resolved relative
1302	to that IO::AIO::WD object.	1569	to that IO::AIO::WD object.
1303		1570
1304	For example, to get a wd object for F</etc> and then stat F<passwd>	1571	For example, to get a wd object for F</etc> and then stat F<passwd>
1305	inside, you would write:	1572	inside, you would write:
1306		1573
…		…
1314	aio_stat [$etcdir, "passwd"], sub {	1581	aio_stat [$etcdir, "passwd"], sub {
1315	# yay	1582	# yay
1316	};	1583	};
1317	};	1584	};
1318		1585
		1586	The fact that C<aio_wd> is a request and not a normal function shows that
1319	This shows that creating an IO::AIO::WD object is itself a potentially	1587	creating an IO::AIO::WD object is itself a potentially blocking operation,
1320	blocking operation, which is why it is done asynchronously.	1588	which is why it is done asynchronously.
		1589
		1590	To stat the directory obtained with C<aio_wd> above, one could write
		1591	either of the following three request calls:
		1592
		1593	aio_lstat "/etc" , sub { ... # pathname as normal string
		1594	aio_lstat [$wd, "."], sub { ... # "." relative to $wd (i.e. $wd itself)
		1595	aio_lstat $wd , sub { ... # shorthand for the previous
1321		1596
1322	As with normal pathnames, IO::AIO keeps a copy of the working directory	1597	As with normal pathnames, IO::AIO keeps a copy of the working directory
1323	object and the pathname string, so you could write the following without	1598	object and the pathname string, so you could write the following without
1324	causing any issues due to C<$path> getting reused:	1599	causing any issues due to C<$path> getting reused:
1325		1600
…		…
1335	There are some caveats: when directories get renamed (or deleted), the	1610	There are some caveats: when directories get renamed (or deleted), the
1336	pathname string doesn't change, so will point to the new directory (or	1611	pathname string doesn't change, so will point to the new directory (or
1337	nowhere at all), while the directory fd, if available on the system,	1612	nowhere at all), while the directory fd, if available on the system,
1338	will still point to the original directory. Most functions accepting a	1613	will still point to the original directory. Most functions accepting a
1339	pathname will use the directory fd on newer systems, and the string on	1614	pathname will use the directory fd on newer systems, and the string on
1340	older systems. Some functions (such as realpath) will always rely on the	1615	older systems. Some functions (such as C<aio_realpath>) will always rely on
1341	string form of the pathname.	1616	the string form of the pathname.
1342		1617
1343	So this fucntionality is mainly useful to get some protection against	1618	So this functionality is mainly useful to get some protection against
1344	C<chdir>, to easily get an absolute path out of a relative path for future	1619	C<chdir>, to easily get an absolute path out of a relative path for future
1345	reference, and to speed up doing many operations in the same directory	1620	reference, and to speed up doing many operations in the same directory
1346	(e.g. when stat'ing all files in a directory).	1621	(e.g. when stat'ing all files in a directory).
1347		1622
1348	The following functions implement this working directory abstraction:	1623	The following functions implement this working directory abstraction:
…		…
1361	passing C<undef> as working directory component of a pathname fails the	1636	passing C<undef> as working directory component of a pathname fails the
1362	request with C<ENOENT>, there is often no need for error checking in the	1637	request with C<ENOENT>, there is often no need for error checking in the
1363	C<aio_wd> callback, as future requests using the value will fail in the	1638	C<aio_wd> callback, as future requests using the value will fail in the
1364	expected way.	1639	expected way.
1365		1640
1366	If this call isn't available because your OS lacks it or it couldn't be
1367	detected, it will be emulated by calling C<fsync> instead.
1368
1369	=item IO::AIO::CWD	1641	=item IO::AIO::CWD
1370		1642
1371	This is a compiletime constant (object) that represents the process	1643	This is a compiletime constant (object) that represents the process
1372	current working directory.	1644	current working directory.
1373		1645
1374	Specifying this object as working directory object for a pathname is as	1646	Specifying this object as working directory object for a pathname is as if
1375	if the pathname would be specified directly, without a directory object,	1647	the pathname would be specified directly, without a directory object. For
1376	e.g., these calls are functionally identical:	1648	example, these calls are functionally identical:
1377		1649
1378	aio_stat "somefile", sub { ... };	1650	aio_stat "somefile", sub { ... };
1379	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };	1651	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };
1380		1652
1381	=back	1653	=back
1382		1654
		1655	To recover the path associated with an IO::AIO::WD object, you can use
		1656	C<aio_realpath>:
		1657
		1658	aio_realpath $wd, sub {
		1659	warn "path is $_[0]\n";
		1660	};
		1661
		1662	Currently, C<aio_statvfs> always, and C<aio_rename> and C<aio_rmdir>
		1663	sometimes, fall back to using an absolue path.
1383		1664
1384	=head2 IO::AIO::REQ CLASS	1665	=head2 IO::AIO::REQ CLASS
1385		1666
1386	All non-aggregate C<aio_*> functions return an object of this class when	1667	All non-aggregate C<aio_*> functions return an object of this class when
1387	called in non-void context.	1668	called in non-void context.
…		…
1565		1846
1566	See C<poll_cb> for an example.	1847	See C<poll_cb> for an example.
1567		1848
1568	=item IO::AIO::poll_cb	1849	=item IO::AIO::poll_cb
1569		1850
1570	Process some outstanding events on the result pipe. You have to call	1851	Process some requests that have reached the result phase (i.e. they have
		1852	been executed but the results are not yet reported). You have to call
		1853	this "regularly" to finish outstanding requests.
		1854
1571	this regularly. Returns C<0> if all events could be processed (or there	1855	Returns C<0> if all events could be processed (or there were no
1572	were no events to process), or C<-1> if it returned earlier for whatever	1856	events to process), or C<-1> if it returned earlier for whatever
1573	reason. Returns immediately when no events are outstanding. The amount of	1857	reason. Returns immediately when no events are outstanding. The amount
1574	events processed depends on the settings of C<IO::AIO::max_poll_req> and	1858	of events processed depends on the settings of C<IO::AIO::max_poll_req>,
1575	C<IO::AIO::max_poll_time>.	1859	C<IO::AIO::max_poll_time> and C<IO::AIO::max_outstanding>.
1576		1860
1577	If not all requests were processed for whatever reason, the filehandle	1861	If not all requests were processed for whatever reason, the poll file
1578	will still be ready when C<poll_cb> returns, so normally you don't have to	1862	descriptor will still be ready when C<poll_cb> returns, so normally you
1579	do anything special to have it called later.	1863	don't have to do anything special to have it called later.
1580		1864
1581	Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes	1865	Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes
1582	ready, it can be beneficial to call this function from loops which submit	1866	ready, it can be beneficial to call this function from loops which submit
1583	a lot of requests, to make sure the results get processed when they become	1867	a lot of requests, to make sure the results get processed when they become
1584	available and not just when the loop is finished and the event loop takes	1868	available and not just when the loop is finished and the event loop takes
…		…
1593	poll => 'r', async => 1,	1877	poll => 'r', async => 1,
1594	cb => \&IO::AIO::poll_cb);	1878	cb => \&IO::AIO::poll_cb);
1595		1879
1596	=item IO::AIO::poll_wait	1880	=item IO::AIO::poll_wait
1597		1881
1598	If there are any outstanding requests and none of them in the result	1882	Wait until either at least one request is in the result phase or no
1599	phase, wait till the result filehandle becomes ready for reading (simply	1883	requests are outstanding anymore.
1600	does a C<select> on the filehandle. This is useful if you want to	1884
1601	synchronously wait for some requests to finish).	1885	This is useful if you want to synchronously wait for some requests to
		1886	become ready, without actually handling them.
1602		1887
1603	See C<nreqs> for an example.	1888	See C<nreqs> for an example.
1604		1889
1605	=item IO::AIO::poll	1890	=item IO::AIO::poll
1606		1891
…		…
1727		2012
1728	This is a very bad function to use in interactive programs because it	2013	This is a very bad function to use in interactive programs because it
1729	blocks, and a bad way to reduce concurrency because it is inexact: Better	2014	blocks, and a bad way to reduce concurrency because it is inexact: Better
1730	use an C<aio_group> together with a feed callback.	2015	use an C<aio_group> together with a feed callback.
1731		2016
1732	It's main use is in scripts without an event loop - when you want to stat	2017	Its main use is in scripts without an event loop - when you want to stat
1733	a lot of files, you can write somehting like this:	2018	a lot of files, you can write something like this:
1734		2019
1735	IO::AIO::max_outstanding 32;	2020	IO::AIO::max_outstanding 32;
1736		2021
1737	for my $path (...) {	2022	for my $path (...) {
1738	aio_stat $path , ...;	2023	aio_stat $path , ...;
…		…
1777		2062
1778	=back	2063	=back
1779		2064
1780	=head3 MISCELLANEOUS FUNCTIONS	2065	=head3 MISCELLANEOUS FUNCTIONS
1781		2066
1782	IO::AIO implements some functions that might be useful, but are not	2067	IO::AIO implements some functions that are useful when you want to use
1783	asynchronous.	2068	some "Advanced I/O" function not available to in Perl, without going the
		2069	"Asynchronous I/O" route. Many of these have an asynchronous C<aio_*>
		2070	counterpart.
1784		2071
1785	=over 4	2072	=over 4
		2073
		2074	=item $numfd = IO::AIO::get_fdlimit
		2075
		2076	This function is I<EXPERIMENTAL> and subject to change.
		2077
		2078	Tries to find the current file descriptor limit and returns it, or
		2079	C<undef> and sets C<$!> in case of an error. The limit is one larger than
		2080	the highest valid file descriptor number.
		2081
		2082	=item IO::AIO::min_fdlimit [$numfd]
		2083
		2084	This function is I<EXPERIMENTAL> and subject to change.
		2085
		2086	Try to increase the current file descriptor limit(s) to at least C<$numfd>
		2087	by changing the soft or hard file descriptor resource limit. If C<$numfd>
		2088	is missing, it will try to set a very high limit, although this is not
		2089	recommended when you know the actual minimum that you require.
		2090
		2091	If the limit cannot be raised enough, the function makes a best-effort
		2092	attempt to increase the limit as much as possible, using various
		2093	tricks, while still failing. You can query the resulting limit using
		2094	C<IO::AIO::get_fdlimit>.
		2095
		2096	If an error occurs, returns C<undef> and sets C<$!>, otherwise returns
		2097	true.
1786		2098
1787	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count	2099	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
1788		2100
1789	Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>,	2101	Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>,
1790	but is blocking (this makes most sense if you know the input data is	2102	but is blocking (this makes most sense if you know the input data is
…		…
1807	=item IO::AIO::madvise $scalar, $offset, $len, $advice	2119	=item IO::AIO::madvise $scalar, $offset, $len, $advice
1808		2120
1809	Simply calls the C<posix_madvise> function (see its	2121	Simply calls the C<posix_madvise> function (see its
1810	manpage for details). The following advice constants are	2122	manpage for details). The following advice constants are
1811	available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,	2123	available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,
1812	C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>.	2124	C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>,
		2125	C<IO::AIO::MADV_DONTNEED>.
		2126
		2127	If C<$offset> is negative, counts from the end. If C<$length> is negative,
		2128	the remaining length of the C<$scalar> is used. If possible, C<$length>
		2129	will be reduced to fit into the C<$scalar>.
1813		2130
1814	On systems that do not implement C<posix_madvise>, this function returns	2131	On systems that do not implement C<posix_madvise>, this function returns
1815	ENOSYS, otherwise the return value of C<posix_madvise>.	2132	ENOSYS, otherwise the return value of C<posix_madvise>.
1816		2133
1817	=item IO::AIO::mprotect $scalar, $offset, $len, $protect	2134	=item IO::AIO::mprotect $scalar, $offset, $len, $protect
…		…
1819	Simply calls the C<mprotect> function on the preferably AIO::mmap'ed	2136	Simply calls the C<mprotect> function on the preferably AIO::mmap'ed
1820	$scalar (see its manpage for details). The following protect	2137	$scalar (see its manpage for details). The following protect
1821	constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,	2138	constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,
1822	C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.	2139	C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.
1823		2140
		2141	If C<$offset> is negative, counts from the end. If C<$length> is negative,
		2142	the remaining length of the C<$scalar> is used. If possible, C<$length>
		2143	will be reduced to fit into the C<$scalar>.
		2144
1824	On systems that do not implement C<mprotect>, this function returns	2145	On systems that do not implement C<mprotect>, this function returns
1825	ENOSYS, otherwise the return value of C<mprotect>.	2146	ENOSYS, otherwise the return value of C<mprotect>.
1826		2147
1827	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]	2148	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]
1828		2149
1829	Memory-maps a file (or anonymous memory range) and attaches it to the	2150	Memory-maps a file (or anonymous memory range) and attaches it to the
1830	given C<$scalar>, which will act like a string scalar.	2151	given C<$scalar>, which will act like a string scalar. Returns true on
		2152	success, and false otherwise.
1831		2153
		2154	The scalar must exist, but its contents do not matter - this means you
		2155	cannot use a nonexistant array or hash element. When in doubt, C<undef>
		2156	the scalar first.
		2157
1832	The only operations allowed on the scalar are C<substr>/C<vec> that don't	2158	The only operations allowed on the mmapped scalar are C<substr>/C<vec>,
1833	change the string length, and most read-only operations such as copying it	2159	which don't change the string length, and most read-only operations such
1834	or searching it with regexes and so on.	2160	as copying it or searching it with regexes and so on.
1835		2161
1836	Anything else is unsafe and will, at best, result in memory leaks.	2162	Anything else is unsafe and will, at best, result in memory leaks.
1837		2163
1838	The memory map associated with the C<$scalar> is automatically removed	2164	The memory map associated with the C<$scalar> is automatically removed
1839	when the C<$scalar> is destroyed, or when the C<IO::AIO::mmap> or	2165	when the C<$scalar> is undef'd or destroyed, or when the C<IO::AIO::mmap>
1840	C<IO::AIO::munmap> functions are called.	2166	or C<IO::AIO::munmap> functions are called on it.
1841		2167
1842	This calls the C<mmap>(2) function internally. See your system's manual	2168	This calls the C<mmap>(2) function internally. See your system's manual
1843	page for details on the C<$length>, C<$prot> and C<$flags> parameters.	2169	page for details on the C<$length>, C<$prot> and C<$flags> parameters.
1844		2170
1845	The C<$length> must be larger than zero and smaller than the actual	2171	The C<$length> must be larger than zero and smaller than the actual
1846	filesize.	2172	filesize.
1847		2173
1848	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,	2174	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,
1849	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,	2175	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,
1850		2176
1851	C<$flags> can be a combination of C<IO::AIO::MAP_SHARED> or	2177	C<$flags> can be a combination of
1852	C<IO::AIO::MAP_PRIVATE>, or a number of system-specific flags (when	2178	C<IO::AIO::MAP_SHARED> or
1853	not available, the are defined as 0): C<IO::AIO::MAP_ANONYMOUS>	2179	C<IO::AIO::MAP_PRIVATE>,
		2180	or a number of system-specific flags (when not available, the are C<0>):
1854	(which is set to C<MAP_ANON> if your system only provides this	2181	C<IO::AIO::MAP_ANONYMOUS> (which is set to C<MAP_ANON> if your system only provides this constant),
1855	constant), C<IO::AIO::MAP_HUGETLB>, C<IO::AIO::MAP_LOCKED>,	2182	C<IO::AIO::MAP_LOCKED>,
1856	C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or	2183	C<IO::AIO::MAP_NORESERVE>,
		2184	C<IO::AIO::MAP_POPULATE>,
1857	C<IO::AIO::MAP_NONBLOCK>	2185	C<IO::AIO::MAP_NONBLOCK>,
		2186	C<IO::AIO::MAP_FIXED>,
		2187	C<IO::AIO::MAP_GROWSDOWN>,
		2188	C<IO::AIO::MAP_32BIT>,
		2189	C<IO::AIO::MAP_HUGETLB> or
		2190	C<IO::AIO::MAP_STACK>.
1858		2191
1859	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.	2192	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.
1860		2193
1861	C<$offset> is the offset from the start of the file - it generally must be	2194	C<$offset> is the offset from the start of the file - it generally must be
1862	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.	2195	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.
…		…
1887		2220
1888	Calls the C<munlockall> function.	2221	Calls the C<munlockall> function.
1889		2222
1890	On systems that do not implement C<munlockall>, this function returns	2223	On systems that do not implement C<munlockall>, this function returns
1891	ENOSYS, otherwise the return value of C<munlockall>.	2224	ENOSYS, otherwise the return value of C<munlockall>.
		2225
		2226	=item IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags
		2227
		2228	Calls the GNU/Linux C<splice(2)> syscall, if available. If C<$r_off> or
		2229	C<$w_off> are C<undef>, then C<NULL> is passed for these, otherwise they
		2230	should be the file offset.
		2231
		2232	C<$r_fh> and C<$w_fh> should not refer to the same file, as splice might
		2233	silently corrupt the data in this case.
		2234
		2235	The following symbol flag values are available: C<IO::AIO::SPLICE_F_MOVE>,
		2236	C<IO::AIO::SPLICE_F_NONBLOCK>, C<IO::AIO::SPLICE_F_MORE> and
		2237	C<IO::AIO::SPLICE_F_GIFT>.
		2238
		2239	See the C<splice(2)> manpage for details.
		2240
		2241	=item IO::AIO::tee $r_fh, $w_fh, $length, $flags
		2242
		2243	Calls the GNU/Linux C<tee(2)> syscall, see its manpage and the
		2244	description for C<IO::AIO::splice> above for details.
		2245
		2246	=item $actual_size = IO::AIO::pipesize $r_fh[, $new_size]
		2247
		2248	Attempts to query or change the pipe buffer size. Obviously works only
		2249	on pipes, and currently works only on GNU/Linux systems, and fails with
		2250	C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer
		2251	size on other systems, drop me a note.
		2252
		2253	=item ($rfh, $wfh) = IO::AIO::pipe2 [$flags]
		2254
		2255	This is a direct interface to the Linux L<pipe2(2)> system call. If
		2256	C<$flags> is missing or C<0>, then this should be the same as a call to
		2257	perl's built-in C<pipe> function and create a new pipe, and works on
		2258	systems that lack the pipe2 syscall. On win32, this case invokes C<_pipe
		2259	(..., 4096, O_BINARY)>.
		2260
		2261	If C<$flags> is non-zero, it tries to invoke the pipe2 system call with
		2262	the given flags (Linux 2.6.27, glibc 2.9).
		2263
		2264	On success, the read and write file handles are returned.
		2265
		2266	On error, nothing will be returned. If the pipe2 syscall is missing and
		2267	C<$flags> is non-zero, fails with C<ENOSYS>.
		2268
		2269	Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the
		2270	time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and
		2271	C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported.
1892		2272
1893	=back	2273	=back
1894		2274
1895	=cut	2275	=cut
1896		2276

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Comparing IO-AIO/AIO.pm (file contents): Revision 1.211 by root, Tue Sep 27 12:10:29 2011 UTC vs. Revision 1.278 by root, Sun Oct 1 07:24:34 2017 UTC

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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.211 by root, Tue Sep 27 12:10:29 2011 UTC vs.
Revision 1.278 by root, Sun Oct 1 07:24:34 2017 UTC