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

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.212 by root, Thu Sep 29 22:42:15 2011 UTC vs.
Revision 1.279 by root, Sat Jan 6 01:04:42 2018 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 = 4.4;
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
		188	aio_slurp
185	aio_wd);	189	aio_wd);
186		190
187	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));	191	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));
188	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush	192	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush
189	min_parallel max_parallel max_idle idle_timeout	193	min_parallel max_parallel max_idle idle_timeout
…		…
202		206
203	=head1 FUNCTIONS	207	=head1 FUNCTIONS
204		208
205	=head2 QUICK OVERVIEW	209	=head2 QUICK OVERVIEW
206		210
207	This section simply lists the prototypes of the most important functions	211	This section simply lists the prototypes most of the functions for
208	for quick reference. See the following sections for function-by-function	212	quick reference. See the following sections for function-by-function
209	documentation.	213	documentation.
210		214
211	aio_wd $pathname, $callback->($wd)	215	aio_wd $pathname, $callback->($wd)
212	aio_open $pathname, $flags, $mode, $callback->($fh)	216	aio_open $pathname, $flags, $mode, $callback->($fh)
213	aio_close $fh, $callback->($status)	217	aio_close $fh, $callback->($status)
		218	aio_seek $fh,$offset,$whence, $callback->($offs)
214	aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	219	aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
215	aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	220	aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
216	aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)	221	aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
217	aio_readahead $fh,$offset,$length, $callback->($retval)	222	aio_readahead $fh,$offset,$length, $callback->($retval)
218	aio_stat $fh_or_path, $callback->($status)	223	aio_stat $fh_or_path, $callback->($status)
219	aio_lstat $fh, $callback->($status)	224	aio_lstat $fh, $callback->($status)
220	aio_statvfs $fh_or_path, $callback->($statvfs)	225	aio_statvfs $fh_or_path, $callback->($statvfs)
221	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	226	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
222	aio_chown $fh_or_path, $uid, $gid, $callback->($status)	227	aio_chown $fh_or_path, $uid, $gid, $callback->($status)
		228	aio_chmod $fh_or_path, $mode, $callback->($status)
223	aio_truncate $fh_or_path, $offset, $callback->($status)	229	aio_truncate $fh_or_path, $offset, $callback->($status)
224	aio_chmod $fh_or_path, $mode, $callback->($status)	230	aio_allocate $fh, $mode, $offset, $len, $callback->($status)
		231	aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
225	aio_unlink $pathname, $callback->($status)	232	aio_unlink $pathname, $callback->($status)
226	aio_mknod $pathname, $mode, $dev, $callback->($status)	233	aio_mknod $pathname, $mode, $dev, $callback->($status)
227	aio_link $srcpath, $dstpath, $callback->($status)	234	aio_link $srcpath, $dstpath, $callback->($status)
228	aio_symlink $srcpath, $dstpath, $callback->($status)	235	aio_symlink $srcpath, $dstpath, $callback->($status)
229	aio_readlink $pathname, $callback->($link)	236	aio_readlink $pathname, $callback->($link)
230	aio_realpath $pathname, $callback->($link)	237	aio_realpath $pathname, $callback->($path)
231	aio_rename $srcpath, $dstpath, $callback->($status)	238	aio_rename $srcpath, $dstpath, $callback->($status)
		239	aio_rename2 $srcpath, $dstpath, $flags, $callback->($status)
232	aio_mkdir $pathname, $mode, $callback->($status)	240	aio_mkdir $pathname, $mode, $callback->($status)
233	aio_rmdir $pathname, $callback->($status)	241	aio_rmdir $pathname, $callback->($status)
234	aio_readdir $pathname, $callback->($entries)	242	aio_readdir $pathname, $callback->($entries)
235	aio_readdirx $pathname, $flags, $callback->($entries, $flags)	243	aio_readdirx $pathname, $flags, $callback->($entries, $flags)
236	IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST	244	IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST
237	IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN	245	IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN
		246	aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
238	aio_load $pathname, $data, $callback->($status)	247	aio_load $pathname, $data, $callback->($status)
239	aio_copy $srcpath, $dstpath, $callback->($status)	248	aio_copy $srcpath, $dstpath, $callback->($status)
240	aio_move $srcpath, $dstpath, $callback->($status)	249	aio_move $srcpath, $dstpath, $callback->($status)
241	aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
242	aio_rmtree $pathname, $callback->($status)	250	aio_rmtree $pathname, $callback->($status)
		251	aio_fcntl $fh, $cmd, $arg, $callback->($status)
		252	aio_ioctl $fh, $request, $buf, $callback->($status)
243	aio_sync $callback->($status)	253	aio_sync $callback->($status)
244	aio_syncfs $fh, $callback->($status)	254	aio_syncfs $fh, $callback->($status)
245	aio_fsync $fh, $callback->($status)	255	aio_fsync $fh, $callback->($status)
246	aio_fdatasync $fh, $callback->($status)	256	aio_fdatasync $fh, $callback->($status)
247	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)	257	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
248	aio_pathsync $pathname, $callback->($status)	258	aio_pathsync $pathname, $callback->($status)
249	aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	259	aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status)
250	aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	260	aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
251	aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)	261	aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
252	aio_mlockall $flags, $callback->($status)	262	aio_mlockall $flags, $callback->($status)
253	aio_group $callback->(...)	263	aio_group $callback->(...)
254	aio_nop $callback->()	264	aio_nop $callback->()
…		…
268	IO::AIO::idle_timeout $seconds	278	IO::AIO::idle_timeout $seconds
269	IO::AIO::max_outstanding $maxreqs	279	IO::AIO::max_outstanding $maxreqs
270	IO::AIO::nreqs	280	IO::AIO::nreqs
271	IO::AIO::nready	281	IO::AIO::nready
272	IO::AIO::npending	282	IO::AIO::npending
		283	$nfd = IO::AIO::get_fdlimit [EXPERIMENTAL]
		284	IO::AIO::min_fdlimit $nfd [EXPERIMENTAL]
273		285
274	IO::AIO::sendfile $ofh, $ifh, $offset, $count	286	IO::AIO::sendfile $ofh, $ifh, $offset, $count
275	IO::AIO::fadvise $fh, $offset, $len, $advice	287	IO::AIO::fadvise $fh, $offset, $len, $advice
		288	IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]]
		289	IO::AIO::munmap $scalar
276	IO::AIO::madvise $scalar, $offset, $length, $advice	290	IO::AIO::madvise $scalar, $offset, $length, $advice
277	IO::AIO::mprotect $scalar, $offset, $length, $protect	291	IO::AIO::mprotect $scalar, $offset, $length, $protect
278	IO::AIO::munlock $scalar, $offset = 0, $length = undef	292	IO::AIO::munlock $scalar, $offset = 0, $length = undef
279	IO::AIO::munlockall	293	IO::AIO::munlockall
280		294
281	=head2 AIO REQUEST FUNCTIONS	295	=head2 API NOTES
282		296
283	All the C<aio_*> calls are more or less thin wrappers around the syscall	297	All the C<aio_*> calls are more or less thin wrappers around the syscall
284	with the same name (sans C<aio_>). The arguments are similar or identical,	298	with the same name (sans C<aio_>). The arguments are similar or identical,
285	and they all accept an additional (and optional) C<$callback> argument	299	and they all accept an additional (and optional) C<$callback> argument
286	which must be a code reference. This code reference will be called after	300	which must be a code reference. This code reference will be called after
…		…
317	correct contents.	331	correct contents.
318		332
319	This works, btw. independent of the internal UTF-8 bit, which IO::AIO	333	This works, btw. independent of the internal UTF-8 bit, which IO::AIO
320	handles correctly whether it is set or not.	334	handles correctly whether it is set or not.
321		335
		336	=head2 AIO REQUEST FUNCTIONS
		337
322	=over 4	338	=over 4
323		339
324	=item $prev_pri = aioreq_pri [$pri]	340	=item $prev_pri = aioreq_pri [$pri]
325		341
326	Returns the priority value that would be used for the next request and, if	342	Returns the priority value that would be used for the next request and, if
…		…
355		371
356		372
357	=item aio_open $pathname, $flags, $mode, $callback->($fh)	373	=item aio_open $pathname, $flags, $mode, $callback->($fh)
358		374
359	Asynchronously open or create a file and call the callback with a newly	375	Asynchronously open or create a file and call the callback with a newly
360	created filehandle for the file.	376	created filehandle for the file (or C<undef> in case of an error).
361		377
362	The pathname passed to C<aio_open> must be absolute. See API NOTES, above,	378	The pathname passed to C<aio_open> must be absolute. See API NOTES, above,
363	for an explanation.	379	for an explanation.
364		380
365	The C<$flags> argument is a bitmask. See the C<Fcntl> module for a	381	The C<$flags> argument is a bitmask. See the C<Fcntl> module for a
…		…
388	following POSIX and non-POSIX constants are available (missing ones on	404	following POSIX and non-POSIX constants are available (missing ones on
389	your system are, as usual, C<0>):	405	your system are, as usual, C<0>):
390		406
391	C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,	407	C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,
392	C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>,	408	C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>,
393	C<O_RSYNC>, C<O_SYNC> and C<O_TTY_INIT>.	409	C<O_RSYNC>, C<O_SYNC>, C<O_PATH>, C<O_TMPFILE>, and C<O_TTY_INIT>.
394		410
395		411
396	=item aio_close $fh, $callback->($status)	412	=item aio_close $fh, $callback->($status)
397		413
398	Asynchronously close a file and call the callback with the result	414	Asynchronously close a file and call the callback with the result
…		…
408	Or in other words: the file descriptor will be closed, but it will not be	424	Or in other words: the file descriptor will be closed, but it will not be
409	free for reuse until the perl filehandle is closed.	425	free for reuse until the perl filehandle is closed.
410		426
411	=cut	427	=cut
412		428
		429	=item aio_seek $fh, $offset, $whence, $callback->($offs)
		430
		431	Seeks the filehandle to the new C<$offset>, similarly to perl's
		432	C<sysseek>. The C<$whence> can use the traditional values (C<0> for
		433	C<IO::AIO::SEEK_SET>, C<1> for C<IO::AIO::SEEK_CUR> or C<2> for
		434	C<IO::AIO::SEEK_END>).
		435
		436	The resulting absolute offset will be passed to the callback, or C<-1> in
		437	case of an error.
		438
		439	In theory, the C<$whence> constants could be different than the
		440	corresponding values from L<Fcntl>, but perl guarantees they are the same,
		441	so don't panic.
		442
		443	As a GNU/Linux (and maybe Solaris) extension, also the constants
		444	C<IO::AIO::SEEK_DATA> and C<IO::AIO::SEEK_HOLE> are available, if they
		445	could be found. No guarantees about suitability for use in C<aio_seek> or
		446	Perl's C<sysseek> can be made though, although I would naively assume they
		447	"just work".
		448
413	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	449	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
414		450
415	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	451	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
416		452
417	Reads or writes C<$length> bytes from or to the specified C<$fh> and	453	Reads or writes C<$length> bytes from or to the specified C<$fh> and
418	C<$offset> into the scalar given by C<$data> and offset C<$dataoffset>	454	C<$offset> into the scalar given by C<$data> and offset C<$dataoffset> and
419	and calls the callback without the actual number of bytes read (or -1 on	455	calls the callback with the actual number of bytes transferred (or -1 on
420	error, just like the syscall).	456	error, just like the syscall).
421		457
422	C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to	458	C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to
423	offset plus the actual number of bytes read.	459	offset plus the actual number of bytes read.
424		460
…		…
482	As native sendfile syscalls (as practically any non-POSIX interface hacked	518	As native sendfile syscalls (as practically any non-POSIX interface hacked
483	together in a hurry to improve benchmark numbers) tend to be rather buggy	519	together in a hurry to improve benchmark numbers) tend to be rather buggy
484	on many systems, this implementation tries to work around some known bugs	520	on many systems, this implementation tries to work around some known bugs
485	in Linux and FreeBSD kernels (probably others, too), but that might fail,	521	in Linux and FreeBSD kernels (probably others, too), but that might fail,
486	so you really really should check the return value of C<aio_sendfile> -	522	so you really really should check the return value of C<aio_sendfile> -
487	fewre bytes than expected might have been transferred.	523	fewer bytes than expected might have been transferred.
488		524
489		525
490	=item aio_readahead $fh,$offset,$length, $callback->($retval)	526	=item aio_readahead $fh,$offset,$length, $callback->($retval)
491		527
492	C<aio_readahead> populates the page cache with data from a file so that	528	C<aio_readahead> populates the page cache with data from a file so that
…		…
496	whole pages, so that offset is effectively rounded down to a page boundary	532	whole pages, so that offset is effectively rounded down to a page boundary
497	and bytes are read up to the next page boundary greater than or equal to	533	and bytes are read up to the next page boundary greater than or equal to
498	(off-set+length). C<aio_readahead> does not read beyond the end of the	534	(off-set+length). C<aio_readahead> does not read beyond the end of the
499	file. The current file offset of the file is left unchanged.	535	file. The current file offset of the file is left unchanged.
500		536
501	If that syscall doesn't exist (likely if your OS isn't Linux) it will be	537	If that syscall doesn't exist (likely if your kernel isn't Linux) it will
502	emulated by simply reading the data, which would have a similar effect.	538	be emulated by simply reading the data, which would have a similar effect.
503		539
504		540
505	=item aio_stat $fh_or_path, $callback->($status)	541	=item aio_stat $fh_or_path, $callback->($status)
506		542
507	=item aio_lstat $fh, $callback->($status)	543	=item aio_lstat $fh, $callback->($status)
…		…
576	namemax => 255,	612	namemax => 255,
577	frsize => 1024,	613	frsize => 1024,
578	fsid => 1810	614	fsid => 1810
579	}	615	}
580		616
		617	Here is a (likely partial - send me updates!) list of fsid values used by
		618	Linux - it is safe to hardcode these when C<$^O> is C<linux>:
		619
		620	0x0000adf5 adfs
		621	0x0000adff affs
		622	0x5346414f afs
		623	0x09041934 anon-inode filesystem
		624	0x00000187 autofs
		625	0x42465331 befs
		626	0x1badface bfs
		627	0x42494e4d binfmt_misc
		628	0x9123683e btrfs
		629	0x0027e0eb cgroupfs
		630	0xff534d42 cifs
		631	0x73757245 coda
		632	0x012ff7b7 coh
		633	0x28cd3d45 cramfs
		634	0x453dcd28 cramfs-wend (wrong endianness)
		635	0x64626720 debugfs
		636	0x00001373 devfs
		637	0x00001cd1 devpts
		638	0x0000f15f ecryptfs
		639	0x00414a53 efs
		640	0x0000137d ext
		641	0x0000ef53 ext2/ext3/ext4
		642	0x0000ef51 ext2
		643	0xf2f52010 f2fs
		644	0x00004006 fat
		645	0x65735546 fuseblk
		646	0x65735543 fusectl
		647	0x0bad1dea futexfs
		648	0x01161970 gfs2
		649	0x47504653 gpfs
		650	0x00004244 hfs
		651	0xf995e849 hpfs
		652	0x00c0ffee hostfs
		653	0x958458f6 hugetlbfs
		654	0x2bad1dea inotifyfs
		655	0x00009660 isofs
		656	0x000072b6 jffs2
		657	0x3153464a jfs
		658	0x6b414653 k-afs
		659	0x0bd00bd0 lustre
		660	0x0000137f minix
		661	0x0000138f minix 30 char names
		662	0x00002468 minix v2
		663	0x00002478 minix v2 30 char names
		664	0x00004d5a minix v3
		665	0x19800202 mqueue
		666	0x00004d44 msdos
		667	0x0000564c novell
		668	0x00006969 nfs
		669	0x6e667364 nfsd
		670	0x00003434 nilfs
		671	0x5346544e ntfs
		672	0x00009fa1 openprom
		673	0x7461636F ocfs2
		674	0x00009fa0 proc
		675	0x6165676c pstorefs
		676	0x0000002f qnx4
		677	0x68191122 qnx6
		678	0x858458f6 ramfs
		679	0x52654973 reiserfs
		680	0x00007275 romfs
		681	0x67596969 rpc_pipefs
		682	0x73636673 securityfs
		683	0xf97cff8c selinux
		684	0x0000517b smb
		685	0x534f434b sockfs
		686	0x73717368 squashfs
		687	0x62656572 sysfs
		688	0x012ff7b6 sysv2
		689	0x012ff7b5 sysv4
		690	0x01021994 tmpfs
		691	0x15013346 udf
		692	0x00011954 ufs
		693	0x54190100 ufs byteswapped
		694	0x00009fa2 usbdevfs
		695	0x01021997 v9fs
		696	0xa501fcf5 vxfs
		697	0xabba1974 xenfs
		698	0x012ff7b4 xenix
		699	0x58465342 xfs
		700	0x012fd16d xia
581		701
582	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	702	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
583		703
584	Works like perl's C<utime> function (including the special case of $atime	704	Works like perl's C<utime> function (including the special case of $atime
585	and $mtime being undef). Fractional times are supported if the underlying	705	and $mtime being undef). Fractional times are supported if the underlying
…		…
613	=item aio_truncate $fh_or_path, $offset, $callback->($status)	733	=item aio_truncate $fh_or_path, $offset, $callback->($status)
614		734
615	Works like truncate(2) or ftruncate(2).	735	Works like truncate(2) or ftruncate(2).
616		736
617		737
		738	=item aio_allocate $fh, $mode, $offset, $len, $callback->($status)
		739
		740	Allocates or frees disk space according to the C<$mode> argument. See the
		741	linux C<fallocate> documentation for details.
		742
		743	C<$mode> is usually C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> to allocate
		744	space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE \| IO::AIO::FALLOC_FL_KEEP_SIZE>,
		745	to deallocate a file range.
		746
		747	IO::AIO also supports C<FALLOC_FL_COLLAPSE_RANGE>, to remove a range
		748	(without leaving a hole), C<FALLOC_FL_ZERO_RANGE>, to zero a range,
		749	C<FALLOC_FL_INSERT_RANGE> to insert a range and C<FALLOC_FL_UNSHARE_RANGE>
		750	to unshare shared blocks (see your L<fallocate(2)> manpage).
		751
		752	The file system block size used by C<fallocate> is presumably the
		753	C<f_bsize> returned by C<statvfs>, but different filesystems and filetypes
		754	can dictate other limitations.
		755
		756	If C<fallocate> isn't available or cannot be emulated (currently no
		757	emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>.
		758
		759
618	=item aio_chmod $fh_or_path, $mode, $callback->($status)	760	=item aio_chmod $fh_or_path, $mode, $callback->($status)
619		761
620	Works like perl's C<chmod> function.	762	Works like perl's C<chmod> function.
621		763
622		764
…		…
659		801
660		802
661	=item aio_realpath $pathname, $callback->($path)	803	=item aio_realpath $pathname, $callback->($path)
662		804
663	Asynchronously make the path absolute and resolve any symlinks in	805	Asynchronously make the path absolute and resolve any symlinks in
664	C<$path>. The resulting path only consists of directories (Same as	806	C<$path>. The resulting path only consists of directories (same as
665	L<Cwd::realpath>).	807	L<Cwd::realpath>).
666		808
667	This request can be used to get the absolute path of the current working	809	This request can be used to get the absolute path of the current working
668	directory by passing it a path of F<.> (a single dot).	810	directory by passing it a path of F<.> (a single dot).
669		811
670		812
671	=item aio_rename $srcpath, $dstpath, $callback->($status)	813	=item aio_rename $srcpath, $dstpath, $callback->($status)
672		814
673	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as	815	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as
674	rename(2) and call the callback with the result code.	816	rename(2) and call the callback with the result code.
		817
		818	On systems that support the AIO::WD working directory abstraction
		819	natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead
		820	of failing, C<rename> is called on the absolute path of C<$wd>.
		821
		822
		823	=item aio_rename2 $srcpath, $dstpath, $flags, $callback->($status)
		824
		825	Basically a version of C<aio_rename> with an additional C<$flags>
		826	argument. Calling this with C<$flags=0> is the same as calling
		827	C<aio_rename>.
		828
		829	Non-zero flags are currently only supported on GNU/Linux systems that
		830	support renameat2. Other systems fail with C<ENOSYS> in this case.
		831
		832	The following constants are available (missing ones are, as usual C<0>),
		833	see renameat2(2) for details:
		834
		835	C<IO::AIO::RENAME_NOREPLACE>, C<IO::AIO::RENAME_EXCHANGE>
		836	and C<IO::AIO::RENAME_WHITEOUT>.
675		837
676		838
677	=item aio_mkdir $pathname, $mode, $callback->($status)	839	=item aio_mkdir $pathname, $mode, $callback->($status)
678		840
679	Asynchronously mkdir (create) a directory and call the callback with	841	Asynchronously mkdir (create) a directory and call the callback with
…		…
683		845
684	=item aio_rmdir $pathname, $callback->($status)	846	=item aio_rmdir $pathname, $callback->($status)
685		847
686	Asynchronously rmdir (delete) a directory and call the callback with the	848	Asynchronously rmdir (delete) a directory and call the callback with the
687	result code.	849	result code.
		850
		851	On systems that support the AIO::WD working directory abstraction
		852	natively, the case C<[$wd, "."]> is specialcased - instead of failing,
		853	C<rmdir> is called on the absolute path of C<$wd>.
688		854
689		855
690	=item aio_readdir $pathname, $callback->($entries)	856	=item aio_readdir $pathname, $callback->($entries)
691		857
692	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire	858	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire
…		…
761	C<$type>'s are known, which can be used to speed up some algorithms.	927	C<$type>'s are known, which can be used to speed up some algorithms.
762		928
763	=back	929	=back
764		930
765		931
		932	=item aio_slurp $pathname, $offset, $length, $data, $callback->($status)
		933
		934	Opens, reads and closes the given file. The data is put into C<$data>,
		935	which is resized as required.
		936
		937	If C<$offset> is negative, then it is counted from the end of the file.
		938
		939	If C<$length> is zero, then the remaining length of the file is
		940	used. Also, in this case, the same limitations to modifying C<$data> apply
		941	as when IO::AIO::mmap is used, i.e. it must only be modified in-place
		942	with C<substr>. If the size of the file is known, specifying a non-zero
		943	C<$length> results in a performance advantage.
		944
		945	This request is similar to the older C<aio_load> request, but since it is
		946	a single request, it might be more efficient to use.
		947
		948	Example: load F</etc/passwd> into C<$passwd>.
		949
		950	my $passwd;
		951	aio_slurp "/etc/passwd", 0, 0, $passwd, sub {
		952	$_[0] >= 0
		953	or die "/etc/passwd: $!\n";
		954
		955	printf "/etc/passwd is %d bytes long, and contains:\n", length $passwd;
		956	print $passwd;
		957	};
		958	IO::AIO::flush;
		959
		960
766	=item aio_load $pathname, $data, $callback->($status)	961	=item aio_load $pathname, $data, $callback->($status)
767		962
768	This is a composite request that tries to fully load the given file into	963	This is a composite request that tries to fully load the given file into
769	memory. Status is the same as with aio_read.	964	memory. Status is the same as with aio_read.
		965
		966	Using C<aio_slurp> might be more efficient, as it is a single request.
770		967
771	=cut	968	=cut
772		969
773	sub aio_load($$;$) {	970	sub aio_load($$;$) {
774	my ($path, undef, $cb) = @_;	971	my ($path, undef, $cb) = @_;
…		…
794	=item aio_copy $srcpath, $dstpath, $callback->($status)	991	=item aio_copy $srcpath, $dstpath, $callback->($status)
795		992
796	Try to copy the I<file> (directories not supported as either source or	993	Try to copy the I<file> (directories not supported as either source or
797	destination) from C<$srcpath> to C<$dstpath> and call the callback with	994	destination) from C<$srcpath> to C<$dstpath> and call the callback with
798	a status of C<0> (ok) or C<-1> (error, see C<$!>).	995	a status of C<0> (ok) or C<-1> (error, see C<$!>).
		996
		997	Existing destination files will be truncated.
799		998
800	This is a composite request that creates the destination file with	999	This is a composite request that creates the destination file with
801	mode 0200 and copies the contents of the source file into it using	1000	mode 0200 and copies the contents of the source file into it using
802	C<aio_sendfile>, followed by restoring atime, mtime, access mode and	1001	C<aio_sendfile>, followed by restoring atime, mtime, access mode and
803	uid/gid, in that order.	1002	uid/gid, in that order.
…		…
913	Scans a directory (similar to C<aio_readdir>) but additionally tries to	1112	Scans a directory (similar to C<aio_readdir>) but additionally tries to
914	efficiently separate the entries of directory C<$path> into two sets of	1113	efficiently separate the entries of directory C<$path> into two sets of
915	names, directories you can recurse into (directories), and ones you cannot	1114	names, directories you can recurse into (directories), and ones you cannot
916	recurse into (everything else, including symlinks to directories).	1115	recurse into (everything else, including symlinks to directories).
917		1116
918	C<aio_scandir> is a composite request that creates of many sub requests_	1117	C<aio_scandir> is a composite request that generates many sub requests.
919	C<$maxreq> specifies the maximum number of outstanding aio requests that	1118	C<$maxreq> specifies the maximum number of outstanding aio requests that
920	this function generates. If it is C<< <= 0 >>, then a suitable default	1119	this function generates. If it is C<< <= 0 >>, then a suitable default
921	will be chosen (currently 4).	1120	will be chosen (currently 4).
922		1121
923	On error, the callback is called without arguments, otherwise it receives	1122	On error, the callback is called without arguments, otherwise it receives
…		…
1057	}	1256	}
1058		1257
1059	=item aio_rmtree $pathname, $callback->($status)	1258	=item aio_rmtree $pathname, $callback->($status)
1060		1259
1061	Delete a directory tree starting (and including) C<$path>, return the	1260	Delete a directory tree starting (and including) C<$path>, return the
1062	status of the final C<rmdir> only. This is a composite request that	1261	status of the final C<rmdir> only. This is a composite request that
1063	uses C<aio_scandir> to recurse into and rmdir directories, and unlink	1262	uses C<aio_scandir> to recurse into and rmdir directories, and unlink
1064	everything else.	1263	everything else.
1065		1264
1066	=cut	1265	=cut
1067		1266
…		…
1088	add $grp $dirgrp;	1287	add $grp $dirgrp;
1089	};	1288	};
1090		1289
1091	$grp	1290	$grp
1092	}	1291	}
		1292
		1293	=item aio_fcntl $fh, $cmd, $arg, $callback->($status)
		1294
		1295	=item aio_ioctl $fh, $request, $buf, $callback->($status)
		1296
		1297	These work just like the C<fcntl> and C<ioctl> built-in functions, except
		1298	they execute asynchronously and pass the return value to the callback.
		1299
		1300	Both calls can be used for a lot of things, some of which make more sense
		1301	to run asynchronously in their own thread, while some others make less
		1302	sense. For example, calls that block waiting for external events, such
		1303	as locking, will also lock down an I/O thread while it is waiting, which
		1304	can deadlock the whole I/O system. At the same time, there might be no
		1305	alternative to using a thread to wait.
		1306
		1307	So in general, you should only use these calls for things that do
		1308	(filesystem) I/O, not for things that wait for other events (network,
		1309	other processes), although if you are careful and know what you are doing,
		1310	you still can.
		1311
		1312	The following constants are available (missing ones are, as usual C<0>):
		1313
		1314	C<F_DUPFD_CLOEXEC>,
		1315
		1316	C<F_OFD_GETLK>, C<F_OFD_SETLK>, C<F_OFD_GETLKW>,
		1317
		1318	C<FIFREEZE>, C<FITHAW>, C<FITRIM>, C<FICLONE>, C<FICLONERANGE>, C<FIDEDUPERANGE>.
		1319
		1320	C<FS_IOC_GETFLAGS>, C<FS_IOC_SETFLAGS>, C<FS_IOC_GETVERSION>, C<FS_IOC_SETVERSION>,
		1321	C<FS_IOC_FIEMAP>.
		1322
		1323	C<FS_IOC_FSGETXATTR>, C<FS_IOC_FSSETXATTR>, C<FS_IOC_SET_ENCRYPTION_POLICY>,
		1324	C<FS_IOC_GET_ENCRYPTION_PWSALT>, C<FS_IOC_GET_ENCRYPTION_POLICY>, C<FS_KEY_DESCRIPTOR_SIZE>.
		1325
		1326	C<FS_SECRM_FL>, C<FS_UNRM_FL>, C<FS_COMPR_FL>, C<FS_SYNC_FL>, C<FS_IMMUTABLE_FL>,
		1327	C<FS_APPEND_FL>, C<FS_NODUMP_FL>, C<FS_NOATIME_FL>, C<FS_DIRTY_FL>,
		1328	C<FS_COMPRBLK_FL>, C<FS_NOCOMP_FL>, C<FS_ENCRYPT_FL>, C<FS_BTREE_FL>,
		1329	C<FS_INDEX_FL>, C<FS_JOURNAL_DATA_FL>, C<FS_NOTAIL_FL>, C<FS_DIRSYNC_FL>, C<FS_TOPDIR_FL>,
		1330	C<FS_FL_USER_MODIFIABLE>.
		1331
		1332	C<FS_XFLAG_REALTIME>, C<FS_XFLAG_PREALLOC>, C<FS_XFLAG_IMMUTABLE>, C<FS_XFLAG_APPEND>,
		1333	C<FS_XFLAG_SYNC>, C<FS_XFLAG_NOATIME>, C<FS_XFLAG_NODUMP>, C<FS_XFLAG_RTINHERIT>,
		1334	C<FS_XFLAG_PROJINHERIT>, C<FS_XFLAG_NOSYMLINKS>, C<FS_XFLAG_EXTSIZE>, C<FS_XFLAG_EXTSZINHERIT>,
		1335	C<FS_XFLAG_NODEFRAG>, C<FS_XFLAG_FILESTREAM>, C<FS_XFLAG_DAX>, C<FS_XFLAG_HASATTR>,
1093		1336
1094	=item aio_sync $callback->($status)	1337	=item aio_sync $callback->($status)
1095		1338
1096	Asynchronously call sync and call the callback when finished.	1339	Asynchronously call sync and call the callback when finished.
1097		1340
…		…
1166	};	1409	};
1167		1410
1168	$grp	1411	$grp
1169	}	1412	}
1170		1413
1171	=item aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	1414	=item aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status)
1172		1415
1173	This is a rather advanced IO::AIO call, which only works on mmap(2)ed	1416	This is a rather advanced IO::AIO call, which only works on mmap(2)ed
1174	scalars (see the C<IO::AIO::mmap> function, although it also works on data	1417	scalars (see the C<IO::AIO::mmap> function, although it also works on data
1175	scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the	1418	scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the
1176	scalar must only be modified in-place while an aio operation is pending on	1419	scalar must only be modified in-place while an aio operation is pending on
…		…
1178		1421
1179	It calls the C<msync> function of your OS, if available, with the memory	1422	It calls the C<msync> function of your OS, if available, with the memory
1180	area starting at C<$offset> in the string and ending C<$length> bytes	1423	area starting at C<$offset> in the string and ending C<$length> bytes
1181	later. If C<$length> is negative, counts from the end, and if C<$length>	1424	later. If C<$length> is negative, counts from the end, and if C<$length>
1182	is C<undef>, then it goes till the end of the string. The flags can be	1425	is C<undef>, then it goes till the end of the string. The flags can be
1183	a combination of C<IO::AIO::MS_ASYNC>, C<IO::AIO::MS_INVALIDATE> and	1426	either C<IO::AIO::MS_ASYNC> or C<IO::AIO::MS_SYNC>, plus an optional
1184	C<IO::AIO::MS_SYNC>.	1427	C<IO::AIO::MS_INVALIDATE>.
1185		1428
1186	=item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	1429	=item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
1187		1430
1188	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1431	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
1189	scalars.	1432	scalars.
1190		1433
1191	It touches (reads or writes) all memory pages in the specified	1434	It touches (reads or writes) all memory pages in the specified
1192	range inside the scalar. All caveats and parameters are the same	1435	range inside the scalar. All caveats and parameters are the same
1193	as for C<aio_msync>, above, except for flags, which must be either	1436	as for C<aio_msync>, above, except for flags, which must be either
1194	C<0> (which reads all pages and ensures they are instantiated) or	1437	C<0> (which reads all pages and ensures they are instantiated) or
1195	C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and	1438	C<IO::AIO::MT_MODIFY>, which modifies the memory pages (by reading and
1196	writing an octet from it, which dirties the page).	1439	writing an octet from it, which dirties the page).
1197		1440
1198	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)	1441	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
1199		1442
1200	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1443	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
…		…
1231	documented under L<MISCELLANEOUS FUNCTIONS>.	1474	documented under L<MISCELLANEOUS FUNCTIONS>.
1232		1475
1233	Example: asynchronously lock all current and future pages into memory.	1476	Example: asynchronously lock all current and future pages into memory.
1234		1477
1235	aio_mlockall IO::AIO::MCL_FUTURE;	1478	aio_mlockall IO::AIO::MCL_FUTURE;
		1479
		1480	=item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
		1481
		1482	Queries the extents of the given file (by calling the Linux C<FIEMAP>
		1483	ioctl, see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If
		1484	the ioctl is not available on your OS, then this request will fail with
		1485	C<ENOSYS>.
		1486
		1487	C<$start> is the starting offset to query extents for, C<$length> is the
		1488	size of the range to query - if it is C<undef>, then the whole file will
		1489	be queried.
		1490
		1491	C<$flags> is a combination of flags (C<IO::AIO::FIEMAP_FLAG_SYNC> or
		1492	C<IO::AIO::FIEMAP_FLAG_XATTR> - C<IO::AIO::FIEMAP_FLAGS_COMPAT> is also
		1493	exported), and is normally C<0> or C<IO::AIO::FIEMAP_FLAG_SYNC> to query
		1494	the data portion.
		1495
		1496	C<$count> is the maximum number of extent records to return. If it is
		1497	C<undef>, then IO::AIO queries all extents of the range. As a very special
		1498	case, if it is C<0>, then the callback receives the number of extents
		1499	instead of the extents themselves (which is unreliable, see below).
		1500
		1501	If an error occurs, the callback receives no arguments. The special
		1502	C<errno> value C<IO::AIO::EBADR> is available to test for flag errors.
		1503
		1504	Otherwise, the callback receives an array reference with extent
		1505	structures. Each extent structure is an array reference itself, with the
		1506	following members:
		1507
		1508	[$logical, $physical, $length, $flags]
		1509
		1510	Flags is any combination of the following flag values (typically either C<0>
		1511	or C<IO::AIO::FIEMAP_EXTENT_LAST> (1)):
		1512
		1513	C<IO::AIO::FIEMAP_EXTENT_LAST>, C<IO::AIO::FIEMAP_EXTENT_UNKNOWN>,
		1514	C<IO::AIO::FIEMAP_EXTENT_DELALLOC>, C<IO::AIO::FIEMAP_EXTENT_ENCODED>,
		1515	C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>,
		1516	C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>,
		1517	C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or
		1518	C<IO::AIO::FIEMAP_EXTENT_SHARED>.
		1519
		1520	At the time of this writing (Linux 3.2), this request is unreliable unless
		1521	C<$count> is C<undef>, as the kernel has all sorts of bugs preventing
		1522	it to return all extents of a range for files with a large number of
		1523	extents. The code (only) works around all these issues if C<$count> is
		1524	C<undef>.
1236		1525
1237	=item aio_group $callback->(...)	1526	=item aio_group $callback->(...)
1238		1527
1239	This is a very special aio request: Instead of doing something, it is a	1528	This is a very special aio request: Instead of doing something, it is a
1240	container for other aio requests, which is useful if you want to bundle	1529	container for other aio requests, which is useful if you want to bundle
…		…
1304	object. This object stores the canonicalised, absolute version of the	1593	object. This object stores the canonicalised, absolute version of the
1305	path, and on systems that allow it, also a directory file descriptor.	1594	path, and on systems that allow it, also a directory file descriptor.
1306		1595
1307	Everywhere where a pathname is accepted by IO::AIO (e.g. in C<aio_stat>	1596	Everywhere where a pathname is accepted by IO::AIO (e.g. in C<aio_stat>
1308	or C<aio_unlink>), one can specify an array reference with an IO::AIO::WD	1597	or C<aio_unlink>), one can specify an array reference with an IO::AIO::WD
1309	object and a pathname instead. If the pathname is absolute, the	1598	object and a pathname instead (or the IO::AIO::WD object alone, which
		1599	gets interpreted as C<[$wd, "."]>). If the pathname is absolute, the
1310	IO::AIO::WD objetc is ignored, otherwise the pathname is resolved relative	1600	IO::AIO::WD object is ignored, otherwise the pathname is resolved relative
1311	to that IO::AIO::WD object.	1601	to that IO::AIO::WD object.
1312		1602
1313	For example, to get a wd object for F</etc> and then stat F<passwd>	1603	For example, to get a wd object for F</etc> and then stat F<passwd>
1314	inside, you would write:	1604	inside, you would write:
1315		1605
…		…
1323	aio_stat [$etcdir, "passwd"], sub {	1613	aio_stat [$etcdir, "passwd"], sub {
1324	# yay	1614	# yay
1325	};	1615	};
1326	};	1616	};
1327		1617
		1618	The fact that C<aio_wd> is a request and not a normal function shows that
1328	This shows that creating an IO::AIO::WD object is itself a potentially	1619	creating an IO::AIO::WD object is itself a potentially blocking operation,
1329	blocking operation, which is why it is done asynchronously.	1620	which is why it is done asynchronously.
		1621
		1622	To stat the directory obtained with C<aio_wd> above, one could write
		1623	either of the following three request calls:
		1624
		1625	aio_lstat "/etc" , sub { ... # pathname as normal string
		1626	aio_lstat [$wd, "."], sub { ... # "." relative to $wd (i.e. $wd itself)
		1627	aio_lstat $wd , sub { ... # shorthand for the previous
1330		1628
1331	As with normal pathnames, IO::AIO keeps a copy of the working directory	1629	As with normal pathnames, IO::AIO keeps a copy of the working directory
1332	object and the pathname string, so you could write the following without	1630	object and the pathname string, so you could write the following without
1333	causing any issues due to C<$path> getting reused:	1631	causing any issues due to C<$path> getting reused:
1334		1632
…		…
1344	There are some caveats: when directories get renamed (or deleted), the	1642	There are some caveats: when directories get renamed (or deleted), the
1345	pathname string doesn't change, so will point to the new directory (or	1643	pathname string doesn't change, so will point to the new directory (or
1346	nowhere at all), while the directory fd, if available on the system,	1644	nowhere at all), while the directory fd, if available on the system,
1347	will still point to the original directory. Most functions accepting a	1645	will still point to the original directory. Most functions accepting a
1348	pathname will use the directory fd on newer systems, and the string on	1646	pathname will use the directory fd on newer systems, and the string on
1349	older systems. Some functions (such as realpath) will always rely on the	1647	older systems. Some functions (such as C<aio_realpath>) will always rely on
1350	string form of the pathname.	1648	the string form of the pathname.
1351		1649
1352	So this fucntionality is mainly useful to get some protection against	1650	So this functionality is mainly useful to get some protection against
1353	C<chdir>, to easily get an absolute path out of a relative path for future	1651	C<chdir>, to easily get an absolute path out of a relative path for future
1354	reference, and to speed up doing many operations in the same directory	1652	reference, and to speed up doing many operations in the same directory
1355	(e.g. when stat'ing all files in a directory).	1653	(e.g. when stat'ing all files in a directory).
1356		1654
1357	The following functions implement this working directory abstraction:	1655	The following functions implement this working directory abstraction:
…		…
1370	passing C<undef> as working directory component of a pathname fails the	1668	passing C<undef> as working directory component of a pathname fails the
1371	request with C<ENOENT>, there is often no need for error checking in the	1669	request with C<ENOENT>, there is often no need for error checking in the
1372	C<aio_wd> callback, as future requests using the value will fail in the	1670	C<aio_wd> callback, as future requests using the value will fail in the
1373	expected way.	1671	expected way.
1374		1672
1375	If this call isn't available because your OS lacks it or it couldn't be
1376	detected, it will be emulated by calling C<fsync> instead.
1377
1378	=item IO::AIO::CWD	1673	=item IO::AIO::CWD
1379		1674
1380	This is a compiletime constant (object) that represents the process	1675	This is a compiletime constant (object) that represents the process
1381	current working directory.	1676	current working directory.
1382		1677
1383	Specifying this object as working directory object for a pathname is as	1678	Specifying this object as working directory object for a pathname is as if
1384	if the pathname would be specified directly, without a directory object,	1679	the pathname would be specified directly, without a directory object. For
1385	e.g., these calls are functionally identical:	1680	example, these calls are functionally identical:
1386		1681
1387	aio_stat "somefile", sub { ... };	1682	aio_stat "somefile", sub { ... };
1388	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };	1683	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };
1389		1684
1390	=back	1685	=back
1391		1686
		1687	To recover the path associated with an IO::AIO::WD object, you can use
		1688	C<aio_realpath>:
		1689
		1690	aio_realpath $wd, sub {
		1691	warn "path is $_[0]\n";
		1692	};
		1693
		1694	Currently, C<aio_statvfs> always, and C<aio_rename> and C<aio_rmdir>
		1695	sometimes, fall back to using an absolue path.
1392		1696
1393	=head2 IO::AIO::REQ CLASS	1697	=head2 IO::AIO::REQ CLASS
1394		1698
1395	All non-aggregate C<aio_*> functions return an object of this class when	1699	All non-aggregate C<aio_*> functions return an object of this class when
1396	called in non-void context.	1700	called in non-void context.
…		…
1574		1878
1575	See C<poll_cb> for an example.	1879	See C<poll_cb> for an example.
1576		1880
1577	=item IO::AIO::poll_cb	1881	=item IO::AIO::poll_cb
1578		1882
1579	Process some outstanding events on the result pipe. You have to call	1883	Process some requests that have reached the result phase (i.e. they have
		1884	been executed but the results are not yet reported). You have to call
		1885	this "regularly" to finish outstanding requests.
		1886
1580	this regularly. Returns C<0> if all events could be processed (or there	1887	Returns C<0> if all events could be processed (or there were no
1581	were no events to process), or C<-1> if it returned earlier for whatever	1888	events to process), or C<-1> if it returned earlier for whatever
1582	reason. Returns immediately when no events are outstanding. The amount of	1889	reason. Returns immediately when no events are outstanding. The amount
1583	events processed depends on the settings of C<IO::AIO::max_poll_req> and	1890	of events processed depends on the settings of C<IO::AIO::max_poll_req>,
1584	C<IO::AIO::max_poll_time>.	1891	C<IO::AIO::max_poll_time> and C<IO::AIO::max_outstanding>.
1585		1892
1586	If not all requests were processed for whatever reason, the filehandle	1893	If not all requests were processed for whatever reason, the poll file
1587	will still be ready when C<poll_cb> returns, so normally you don't have to	1894	descriptor will still be ready when C<poll_cb> returns, so normally you
1588	do anything special to have it called later.	1895	don't have to do anything special to have it called later.
1589		1896
1590	Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes	1897	Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes
1591	ready, it can be beneficial to call this function from loops which submit	1898	ready, it can be beneficial to call this function from loops which submit
1592	a lot of requests, to make sure the results get processed when they become	1899	a lot of requests, to make sure the results get processed when they become
1593	available and not just when the loop is finished and the event loop takes	1900	available and not just when the loop is finished and the event loop takes
…		…
1602	poll => 'r', async => 1,	1909	poll => 'r', async => 1,
1603	cb => \&IO::AIO::poll_cb);	1910	cb => \&IO::AIO::poll_cb);
1604		1911
1605	=item IO::AIO::poll_wait	1912	=item IO::AIO::poll_wait
1606		1913
1607	If there are any outstanding requests and none of them in the result	1914	Wait until either at least one request is in the result phase or no
1608	phase, wait till the result filehandle becomes ready for reading (simply	1915	requests are outstanding anymore.
1609	does a C<select> on the filehandle. This is useful if you want to	1916
1610	synchronously wait for some requests to finish).	1917	This is useful if you want to synchronously wait for some requests to
		1918	become ready, without actually handling them.
1611		1919
1612	See C<nreqs> for an example.	1920	See C<nreqs> for an example.
1613		1921
1614	=item IO::AIO::poll	1922	=item IO::AIO::poll
1615		1923
…		…
1736		2044
1737	This is a very bad function to use in interactive programs because it	2045	This is a very bad function to use in interactive programs because it
1738	blocks, and a bad way to reduce concurrency because it is inexact: Better	2046	blocks, and a bad way to reduce concurrency because it is inexact: Better
1739	use an C<aio_group> together with a feed callback.	2047	use an C<aio_group> together with a feed callback.
1740		2048
1741	It's main use is in scripts without an event loop - when you want to stat	2049	Its main use is in scripts without an event loop - when you want to stat
1742	a lot of files, you can write somehting like this:	2050	a lot of files, you can write something like this:
1743		2051
1744	IO::AIO::max_outstanding 32;	2052	IO::AIO::max_outstanding 32;
1745		2053
1746	for my $path (...) {	2054	for my $path (...) {
1747	aio_stat $path , ...;	2055	aio_stat $path , ...;
…		…
1786		2094
1787	=back	2095	=back
1788		2096
1789	=head3 MISCELLANEOUS FUNCTIONS	2097	=head3 MISCELLANEOUS FUNCTIONS
1790		2098
1791	IO::AIO implements some functions that might be useful, but are not	2099	IO::AIO implements some functions that are useful when you want to use
1792	asynchronous.	2100	some "Advanced I/O" function not available to in Perl, without going the
		2101	"Asynchronous I/O" route. Many of these have an asynchronous C<aio_*>
		2102	counterpart.
1793		2103
1794	=over 4	2104	=over 4
		2105
		2106	=item $numfd = IO::AIO::get_fdlimit
		2107
		2108	This function is I<EXPERIMENTAL> and subject to change.
		2109
		2110	Tries to find the current file descriptor limit and returns it, or
		2111	C<undef> and sets C<$!> in case of an error. The limit is one larger than
		2112	the highest valid file descriptor number.
		2113
		2114	=item IO::AIO::min_fdlimit [$numfd]
		2115
		2116	This function is I<EXPERIMENTAL> and subject to change.
		2117
		2118	Try to increase the current file descriptor limit(s) to at least C<$numfd>
		2119	by changing the soft or hard file descriptor resource limit. If C<$numfd>
		2120	is missing, it will try to set a very high limit, although this is not
		2121	recommended when you know the actual minimum that you require.
		2122
		2123	If the limit cannot be raised enough, the function makes a best-effort
		2124	attempt to increase the limit as much as possible, using various
		2125	tricks, while still failing. You can query the resulting limit using
		2126	C<IO::AIO::get_fdlimit>.
		2127
		2128	If an error occurs, returns C<undef> and sets C<$!>, otherwise returns
		2129	true.
1795		2130
1796	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count	2131	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
1797		2132
1798	Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>,	2133	Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>,
1799	but is blocking (this makes most sense if you know the input data is	2134	but is blocking (this makes most sense if you know the input data is
…		…
1816	=item IO::AIO::madvise $scalar, $offset, $len, $advice	2151	=item IO::AIO::madvise $scalar, $offset, $len, $advice
1817		2152
1818	Simply calls the C<posix_madvise> function (see its	2153	Simply calls the C<posix_madvise> function (see its
1819	manpage for details). The following advice constants are	2154	manpage for details). The following advice constants are
1820	available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,	2155	available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,
1821	C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>.	2156	C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>,
		2157	C<IO::AIO::MADV_DONTNEED>.
		2158
		2159	If C<$offset> is negative, counts from the end. If C<$length> is negative,
		2160	the remaining length of the C<$scalar> is used. If possible, C<$length>
		2161	will be reduced to fit into the C<$scalar>.
1822		2162
1823	On systems that do not implement C<posix_madvise>, this function returns	2163	On systems that do not implement C<posix_madvise>, this function returns
1824	ENOSYS, otherwise the return value of C<posix_madvise>.	2164	ENOSYS, otherwise the return value of C<posix_madvise>.
1825		2165
1826	=item IO::AIO::mprotect $scalar, $offset, $len, $protect	2166	=item IO::AIO::mprotect $scalar, $offset, $len, $protect
…		…
1828	Simply calls the C<mprotect> function on the preferably AIO::mmap'ed	2168	Simply calls the C<mprotect> function on the preferably AIO::mmap'ed
1829	$scalar (see its manpage for details). The following protect	2169	$scalar (see its manpage for details). The following protect
1830	constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,	2170	constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,
1831	C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.	2171	C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.
1832		2172
		2173	If C<$offset> is negative, counts from the end. If C<$length> is negative,
		2174	the remaining length of the C<$scalar> is used. If possible, C<$length>
		2175	will be reduced to fit into the C<$scalar>.
		2176
1833	On systems that do not implement C<mprotect>, this function returns	2177	On systems that do not implement C<mprotect>, this function returns
1834	ENOSYS, otherwise the return value of C<mprotect>.	2178	ENOSYS, otherwise the return value of C<mprotect>.
1835		2179
1836	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]	2180	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]
1837		2181
1838	Memory-maps a file (or anonymous memory range) and attaches it to the	2182	Memory-maps a file (or anonymous memory range) and attaches it to the
1839	given C<$scalar>, which will act like a string scalar.	2183	given C<$scalar>, which will act like a string scalar. Returns true on
		2184	success, and false otherwise.
1840		2185
		2186	The scalar must exist, but its contents do not matter - this means you
		2187	cannot use a nonexistant array or hash element. When in doubt, C<undef>
		2188	the scalar first.
		2189
1841	The only operations allowed on the scalar are C<substr>/C<vec> that don't	2190	The only operations allowed on the mmapped scalar are C<substr>/C<vec>,
1842	change the string length, and most read-only operations such as copying it	2191	which don't change the string length, and most read-only operations such
1843	or searching it with regexes and so on.	2192	as copying it or searching it with regexes and so on.
1844		2193
1845	Anything else is unsafe and will, at best, result in memory leaks.	2194	Anything else is unsafe and will, at best, result in memory leaks.
1846		2195
1847	The memory map associated with the C<$scalar> is automatically removed	2196	The memory map associated with the C<$scalar> is automatically removed
1848	when the C<$scalar> is destroyed, or when the C<IO::AIO::mmap> or	2197	when the C<$scalar> is undef'd or destroyed, or when the C<IO::AIO::mmap>
1849	C<IO::AIO::munmap> functions are called.	2198	or C<IO::AIO::munmap> functions are called on it.
1850		2199
1851	This calls the C<mmap>(2) function internally. See your system's manual	2200	This calls the C<mmap>(2) function internally. See your system's manual
1852	page for details on the C<$length>, C<$prot> and C<$flags> parameters.	2201	page for details on the C<$length>, C<$prot> and C<$flags> parameters.
1853		2202
1854	The C<$length> must be larger than zero and smaller than the actual	2203	The C<$length> must be larger than zero and smaller than the actual
1855	filesize.	2204	filesize.
1856		2205
1857	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,	2206	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,
1858	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,	2207	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,
1859		2208
1860	C<$flags> can be a combination of C<IO::AIO::MAP_SHARED> or	2209	C<$flags> can be a combination of
1861	C<IO::AIO::MAP_PRIVATE>, or a number of system-specific flags (when	2210	C<IO::AIO::MAP_SHARED> or
1862	not available, the are defined as 0): C<IO::AIO::MAP_ANONYMOUS>	2211	C<IO::AIO::MAP_PRIVATE>,
		2212	or a number of system-specific flags (when not available, the are C<0>):
1863	(which is set to C<MAP_ANON> if your system only provides this	2213	C<IO::AIO::MAP_ANONYMOUS> (which is set to C<MAP_ANON> if your system only provides this constant),
1864	constant), C<IO::AIO::MAP_HUGETLB>, C<IO::AIO::MAP_LOCKED>,	2214	C<IO::AIO::MAP_LOCKED>,
1865	C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or	2215	C<IO::AIO::MAP_NORESERVE>,
		2216	C<IO::AIO::MAP_POPULATE>,
1866	C<IO::AIO::MAP_NONBLOCK>	2217	C<IO::AIO::MAP_NONBLOCK>,
		2218	C<IO::AIO::MAP_FIXED>,
		2219	C<IO::AIO::MAP_GROWSDOWN>,
		2220	C<IO::AIO::MAP_32BIT>,
		2221	C<IO::AIO::MAP_HUGETLB> or
		2222	C<IO::AIO::MAP_STACK>.
1867		2223
1868	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.	2224	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.
1869		2225
1870	C<$offset> is the offset from the start of the file - it generally must be	2226	C<$offset> is the offset from the start of the file - it generally must be
1871	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.	2227	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.
…		…
1896		2252
1897	Calls the C<munlockall> function.	2253	Calls the C<munlockall> function.
1898		2254
1899	On systems that do not implement C<munlockall>, this function returns	2255	On systems that do not implement C<munlockall>, this function returns
1900	ENOSYS, otherwise the return value of C<munlockall>.	2256	ENOSYS, otherwise the return value of C<munlockall>.
		2257
		2258	=item IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags
		2259
		2260	Calls the GNU/Linux C<splice(2)> syscall, if available. If C<$r_off> or
		2261	C<$w_off> are C<undef>, then C<NULL> is passed for these, otherwise they
		2262	should be the file offset.
		2263
		2264	C<$r_fh> and C<$w_fh> should not refer to the same file, as splice might
		2265	silently corrupt the data in this case.
		2266
		2267	The following symbol flag values are available: C<IO::AIO::SPLICE_F_MOVE>,
		2268	C<IO::AIO::SPLICE_F_NONBLOCK>, C<IO::AIO::SPLICE_F_MORE> and
		2269	C<IO::AIO::SPLICE_F_GIFT>.
		2270
		2271	See the C<splice(2)> manpage for details.
		2272
		2273	=item IO::AIO::tee $r_fh, $w_fh, $length, $flags
		2274
		2275	Calls the GNU/Linux C<tee(2)> syscall, see its manpage and the
		2276	description for C<IO::AIO::splice> above for details.
		2277
		2278	=item $actual_size = IO::AIO::pipesize $r_fh[, $new_size]
		2279
		2280	Attempts to query or change the pipe buffer size. Obviously works only
		2281	on pipes, and currently works only on GNU/Linux systems, and fails with
		2282	C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer
		2283	size on other systems, drop me a note.
		2284
		2285	=item ($rfh, $wfh) = IO::AIO::pipe2 [$flags]
		2286
		2287	This is a direct interface to the Linux L<pipe2(2)> system call. If
		2288	C<$flags> is missing or C<0>, then this should be the same as a call to
		2289	perl's built-in C<pipe> function and create a new pipe, and works on
		2290	systems that lack the pipe2 syscall. On win32, this case invokes C<_pipe
		2291	(..., 4096, O_BINARY)>.
		2292
		2293	If C<$flags> is non-zero, it tries to invoke the pipe2 system call with
		2294	the given flags (Linux 2.6.27, glibc 2.9).
		2295
		2296	On success, the read and write file handles are returned.
		2297
		2298	On error, nothing will be returned. If the pipe2 syscall is missing and
		2299	C<$flags> is non-zero, fails with C<ENOSYS>.
		2300
		2301	Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the
		2302	time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and
		2303	C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported.
1901		2304
1902	=back	2305	=back
1903		2306
1904	=cut	2307	=cut
1905		2308

Diff Legend

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

Comparing IO-AIO/AIO.pm (file contents): Revision 1.212 by root, Thu Sep 29 22:42:15 2011 UTC vs. Revision 1.279 by root, Sat Jan 6 01:04:42 2018 UTC

Diff Legend

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.212 by root, Thu Sep 29 22:42:15 2011 UTC vs.
Revision 1.279 by root, Sat Jan 6 01:04:42 2018 UTC