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

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.220 by root, Sun Apr 1 17:46:02 2012 UTC vs.
Revision 1.258 by root, Thu Jan 21 23:04:46 2016 UTC

…		…
68	=head2 EXAMPLE	68	=head2 EXAMPLE
69		69
70	This is a simple example that uses the EV module and loads	70	This is a simple example that uses the EV module and loads
71	F</etc/passwd> asynchronously:	71	F</etc/passwd> asynchronously:
72		72
73	use Fcntl;
74	use EV;	73	use EV;
75	use IO::AIO;	74	use IO::AIO;
76		75
77	# register the IO::AIO callback with EV	76	# register the IO::AIO callback with EV
78	my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;	77	my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
…		…
95		94
96	# file contents now in $contents	95	# file contents now in $contents
97	print $contents;	96	print $contents;
98		97
99	# exit event loop and program	98	# exit event loop and program
100	EV::unloop;	99	EV::break;
101	};	100	};
102	};	101	};
103		102
104	# possibly queue up other requests, or open GUI windows,	103	# possibly queue up other requests, or open GUI windows,
105	# check for sockets etc. etc.	104	# check for sockets etc. etc.
106		105
107	# process events as long as there are some:	106	# process events as long as there are some:
108	EV::loop;	107	EV::run;
109		108
110	=head1 REQUEST ANATOMY AND LIFETIME	109	=head1 REQUEST ANATOMY AND LIFETIME
111		110
112	Every C<aio_*> function creates a request. which is a C data structure not	111	Every C<aio_*> function creates a request. which is a C data structure not
113	directly visible to Perl.	112	directly visible to Perl.
…		…
168	use common::sense;	167	use common::sense;
169		168
170	use base 'Exporter';	169	use base 'Exporter';
171		170
172	BEGIN {	171	BEGIN {
173	our $VERSION = '4.13';	172	our $VERSION = 4.33;
174		173
175	our @AIO_REQ = qw(aio_sendfile aio_seek aio_read aio_write aio_open aio_close	174	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	175	aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx
177	aio_scandir aio_symlink aio_readlink aio_realpath aio_sync	176	aio_scandir aio_symlink aio_readlink aio_realpath aio_sync
178	aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range aio_fallocate	177	aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range aio_allocate
179	aio_pathsync aio_readahead	178	aio_pathsync aio_readahead aio_fiemap
180	aio_rename aio_link aio_move aio_copy aio_group	179	aio_rename aio_link aio_move aio_copy aio_group
181	aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown	180	aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown
182	aio_chmod aio_utime aio_truncate	181	aio_chmod aio_utime aio_truncate
183	aio_msync aio_mtouch aio_mlock aio_mlockall	182	aio_msync aio_mtouch aio_mlock aio_mlockall
184	aio_statvfs	183	aio_statvfs
…		…
202		201
203	=head1 FUNCTIONS	202	=head1 FUNCTIONS
204		203
205	=head2 QUICK OVERVIEW	204	=head2 QUICK OVERVIEW
206		205
207	This section simply lists the prototypes of the most important functions	206	This section simply lists the prototypes most of the functions for
208	for quick reference. See the following sections for function-by-function	207	quick reference. See the following sections for function-by-function
209	documentation.	208	documentation.
210		209
211	aio_wd $pathname, $callback->($wd)	210	aio_wd $pathname, $callback->($wd)
212	aio_open $pathname, $flags, $mode, $callback->($fh)	211	aio_open $pathname, $flags, $mode, $callback->($fh)
213	aio_close $fh, $callback->($status)	212	aio_close $fh, $callback->($status)
…		…
221	aio_statvfs $fh_or_path, $callback->($statvfs)	220	aio_statvfs $fh_or_path, $callback->($statvfs)
222	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	221	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
223	aio_chown $fh_or_path, $uid, $gid, $callback->($status)	222	aio_chown $fh_or_path, $uid, $gid, $callback->($status)
224	aio_chmod $fh_or_path, $mode, $callback->($status)	223	aio_chmod $fh_or_path, $mode, $callback->($status)
225	aio_truncate $fh_or_path, $offset, $callback->($status)	224	aio_truncate $fh_or_path, $offset, $callback->($status)
		225	aio_allocate $fh, $mode, $offset, $len, $callback->($status)
		226	aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
226	aio_unlink $pathname, $callback->($status)	227	aio_unlink $pathname, $callback->($status)
227	aio_mknod $pathname, $mode, $dev, $callback->($status)	228	aio_mknod $pathname, $mode, $dev, $callback->($status)
228	aio_link $srcpath, $dstpath, $callback->($status)	229	aio_link $srcpath, $dstpath, $callback->($status)
229	aio_symlink $srcpath, $dstpath, $callback->($status)	230	aio_symlink $srcpath, $dstpath, $callback->($status)
230	aio_readlink $pathname, $callback->($link)	231	aio_readlink $pathname, $callback->($link)
231	aio_realpath $pathname, $callback->($link)	232	aio_realpath $pathname, $callback->($path)
232	aio_rename $srcpath, $dstpath, $callback->($status)	233	aio_rename $srcpath, $dstpath, $callback->($status)
233	aio_mkdir $pathname, $mode, $callback->($status)	234	aio_mkdir $pathname, $mode, $callback->($status)
234	aio_rmdir $pathname, $callback->($status)	235	aio_rmdir $pathname, $callback->($status)
235	aio_readdir $pathname, $callback->($entries)	236	aio_readdir $pathname, $callback->($entries)
236	aio_readdirx $pathname, $flags, $callback->($entries, $flags)	237	aio_readdirx $pathname, $flags, $callback->($entries, $flags)
…		…
272	IO::AIO::nready	273	IO::AIO::nready
273	IO::AIO::npending	274	IO::AIO::npending
274		275
275	IO::AIO::sendfile $ofh, $ifh, $offset, $count	276	IO::AIO::sendfile $ofh, $ifh, $offset, $count
276	IO::AIO::fadvise $fh, $offset, $len, $advice	277	IO::AIO::fadvise $fh, $offset, $len, $advice
		278	IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]]
		279	IO::AIO::munmap $scalar
277	IO::AIO::madvise $scalar, $offset, $length, $advice	280	IO::AIO::madvise $scalar, $offset, $length, $advice
278	IO::AIO::mprotect $scalar, $offset, $length, $protect	281	IO::AIO::mprotect $scalar, $offset, $length, $protect
279	IO::AIO::munlock $scalar, $offset = 0, $length = undef	282	IO::AIO::munlock $scalar, $offset = 0, $length = undef
280	IO::AIO::munlockall	283	IO::AIO::munlockall
281		284
…		…
358		361
359		362
360	=item aio_open $pathname, $flags, $mode, $callback->($fh)	363	=item aio_open $pathname, $flags, $mode, $callback->($fh)
361		364
362	Asynchronously open or create a file and call the callback with a newly	365	Asynchronously open or create a file and call the callback with a newly
363	created filehandle for the file.	366	created filehandle for the file (or C<undef> in case of an error).
364		367
365	The pathname passed to C<aio_open> must be absolute. See API NOTES, above,	368	The pathname passed to C<aio_open> must be absolute. See API NOTES, above,
366	for an explanation.	369	for an explanation.
367		370
368	The C<$flags> argument is a bitmask. See the C<Fcntl> module for a	371	The C<$flags> argument is a bitmask. See the C<Fcntl> module for a
…		…
391	following POSIX and non-POSIX constants are available (missing ones on	394	following POSIX and non-POSIX constants are available (missing ones on
392	your system are, as usual, C<0>):	395	your system are, as usual, C<0>):
393		396
394	C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,	397	C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,
395	C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>,	398	C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>,
396	C<O_RSYNC>, C<O_SYNC> and C<O_TTY_INIT>.	399	C<O_RSYNC>, C<O_SYNC>, C<O_PATH>, C<O_TMPFILE>, and C<O_TTY_INIT>.
397		400
398		401
399	=item aio_close $fh, $callback->($status)	402	=item aio_close $fh, $callback->($status)
400		403
401	Asynchronously close a file and call the callback with the result	404	Asynchronously close a file and call the callback with the result
…		…
413		416
414	=cut	417	=cut
415		418
416	=item aio_seek $fh, $offset, $whence, $callback->($offs)	419	=item aio_seek $fh, $offset, $whence, $callback->($offs)
417		420
418	Seeks the filehandle to the new C<$offset>, similarly to perl'S	421	Seeks the filehandle to the new C<$offset>, similarly to perl's
419	C<sysseek>. The C<$whence> can use the traditional values (C<0> for	422	C<sysseek>. The C<$whence> can use the traditional values (C<0> for
420	C<IO::AIO::SEEK_SET>, C<1> for C<IO::AIO::SEEK_CUR> or C<2> for	423	C<IO::AIO::SEEK_SET>, C<1> for C<IO::AIO::SEEK_CUR> or C<2> for
421	C<IO::AIO::SEEK_END>).	424	C<IO::AIO::SEEK_END>).
422		425
423	The resulting absolute offset will be passed to the callback, or C<-1> in	426	The resulting absolute offset will be passed to the callback, or C<-1> in
424	case of an error.	427	case of an error.
425		428
426	In theory, the C<$whence> constants could be different than the	429	In theory, the C<$whence> constants could be different than the
427	corresponding values from L<Fcntl>, but perl guarantees they are the same,	430	corresponding values from L<Fcntl>, but perl guarantees they are the same,
428	so don't panic.	431	so don't panic.
		432
		433	As a GNU/Linux (and maybe Solaris) extension, also the constants
		434	C<IO::AIO::SEEK_DATA> and C<IO::AIO::SEEK_HOLE> are available, if they
		435	could be found. No guarantees about suitability for use in C<aio_seek> or
		436	Perl's C<sysseek> can be made though, although I would naively assume they
		437	"just work".
429		438
430	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	439	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
431		440
432	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	441	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
433		442
…		…
593	namemax => 255,	602	namemax => 255,
594	frsize => 1024,	603	frsize => 1024,
595	fsid => 1810	604	fsid => 1810
596	}	605	}
597		606
		607	Here is a (likely partial - send me updates!) list of fsid values used by
		608	Linux - it is safe to hardcode these when C<$^O> is C<linux>:
		609
		610	0x0000adf5 adfs
		611	0x0000adff affs
		612	0x5346414f afs
		613	0x09041934 anon-inode filesystem
		614	0x00000187 autofs
		615	0x42465331 befs
		616	0x1badface bfs
		617	0x42494e4d binfmt_misc
		618	0x9123683e btrfs
		619	0x0027e0eb cgroupfs
		620	0xff534d42 cifs
		621	0x73757245 coda
		622	0x012ff7b7 coh
		623	0x28cd3d45 cramfs
		624	0x453dcd28 cramfs-wend (wrong endianness)
		625	0x64626720 debugfs
		626	0x00001373 devfs
		627	0x00001cd1 devpts
		628	0x0000f15f ecryptfs
		629	0x00414a53 efs
		630	0x0000137d ext
		631	0x0000ef53 ext2/ext3/ext4
		632	0x0000ef51 ext2
		633	0xf2f52010 f2fs
		634	0x00004006 fat
		635	0x65735546 fuseblk
		636	0x65735543 fusectl
		637	0x0bad1dea futexfs
		638	0x01161970 gfs2
		639	0x47504653 gpfs
		640	0x00004244 hfs
		641	0xf995e849 hpfs
		642	0x00c0ffee hostfs
		643	0x958458f6 hugetlbfs
		644	0x2bad1dea inotifyfs
		645	0x00009660 isofs
		646	0x000072b6 jffs2
		647	0x3153464a jfs
		648	0x6b414653 k-afs
		649	0x0bd00bd0 lustre
		650	0x0000137f minix
		651	0x0000138f minix 30 char names
		652	0x00002468 minix v2
		653	0x00002478 minix v2 30 char names
		654	0x00004d5a minix v3
		655	0x19800202 mqueue
		656	0x00004d44 msdos
		657	0x0000564c novell
		658	0x00006969 nfs
		659	0x6e667364 nfsd
		660	0x00003434 nilfs
		661	0x5346544e ntfs
		662	0x00009fa1 openprom
		663	0x7461636F ocfs2
		664	0x00009fa0 proc
		665	0x6165676c pstorefs
		666	0x0000002f qnx4
		667	0x68191122 qnx6
		668	0x858458f6 ramfs
		669	0x52654973 reiserfs
		670	0x00007275 romfs
		671	0x67596969 rpc_pipefs
		672	0x73636673 securityfs
		673	0xf97cff8c selinux
		674	0x0000517b smb
		675	0x534f434b sockfs
		676	0x73717368 squashfs
		677	0x62656572 sysfs
		678	0x012ff7b6 sysv2
		679	0x012ff7b5 sysv4
		680	0x01021994 tmpfs
		681	0x15013346 udf
		682	0x00011954 ufs
		683	0x54190100 ufs byteswapped
		684	0x00009fa2 usbdevfs
		685	0x01021997 v9fs
		686	0xa501fcf5 vxfs
		687	0xabba1974 xenfs
		688	0x012ff7b4 xenix
		689	0x58465342 xfs
		690	0x012fd16d xia
598		691
599	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	692	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
600		693
601	Works like perl's C<utime> function (including the special case of $atime	694	Works like perl's C<utime> function (including the special case of $atime
602	and $mtime being undef). Fractional times are supported if the underlying	695	and $mtime being undef). Fractional times are supported if the underlying
…		…
630	=item aio_truncate $fh_or_path, $offset, $callback->($status)	723	=item aio_truncate $fh_or_path, $offset, $callback->($status)
631		724
632	Works like truncate(2) or ftruncate(2).	725	Works like truncate(2) or ftruncate(2).
633		726
634		727
		728	=item aio_allocate $fh, $mode, $offset, $len, $callback->($status)
		729
		730	Allocates or frees disk space according to the C<$mode> argument. See the
		731	linux C<fallocate> documentation for details.
		732
		733	C<$mode> is usually C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> to allocate
		734	space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE \| IO::AIO::FALLOC_FL_KEEP_SIZE>,
		735	to deallocate a file range.
		736
		737	IO::AIO also supports C<FALLOC_FL_COLLAPSE_RANGE>, to remove a range
		738	(without leaving a hole) and C<FALLOC_FL_ZERO_RANGE>, to zero a range (see
		739	your L<fallocate(2)> manpage).
		740
		741	The file system block size used by C<fallocate> is presumably the
		742	C<f_bsize> returned by C<statvfs>.
		743
		744	If C<fallocate> isn't available or cannot be emulated (currently no
		745	emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>.
		746
		747
635	=item aio_chmod $fh_or_path, $mode, $callback->($status)	748	=item aio_chmod $fh_or_path, $mode, $callback->($status)
636		749
637	Works like perl's C<chmod> function.	750	Works like perl's C<chmod> function.
638		751
639		752
…		…
676		789
677		790
678	=item aio_realpath $pathname, $callback->($path)	791	=item aio_realpath $pathname, $callback->($path)
679		792
680	Asynchronously make the path absolute and resolve any symlinks in	793	Asynchronously make the path absolute and resolve any symlinks in
681	C<$path>. The resulting path only consists of directories (Same as	794	C<$path>. The resulting path only consists of directories (same as
682	L<Cwd::realpath>).	795	L<Cwd::realpath>).
683		796
684	This request can be used to get the absolute path of the current working	797	This request can be used to get the absolute path of the current working
685	directory by passing it a path of F<.> (a single dot).	798	directory by passing it a path of F<.> (a single dot).
686		799
687		800
688	=item aio_rename $srcpath, $dstpath, $callback->($status)	801	=item aio_rename $srcpath, $dstpath, $callback->($status)
689		802
690	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as	803	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as
691	rename(2) and call the callback with the result code.	804	rename(2) and call the callback with the result code.
		805
		806	On systems that support the AIO::WD working directory abstraction
		807	natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead
		808	of failing, C<rename> is called on the absolute path of C<$wd>.
692		809
693		810
694	=item aio_mkdir $pathname, $mode, $callback->($status)	811	=item aio_mkdir $pathname, $mode, $callback->($status)
695		812
696	Asynchronously mkdir (create) a directory and call the callback with	813	Asynchronously mkdir (create) a directory and call the callback with
…		…
700		817
701	=item aio_rmdir $pathname, $callback->($status)	818	=item aio_rmdir $pathname, $callback->($status)
702		819
703	Asynchronously rmdir (delete) a directory and call the callback with the	820	Asynchronously rmdir (delete) a directory and call the callback with the
704	result code.	821	result code.
		822
		823	On systems that support the AIO::WD working directory abstraction
		824	natively, the case C<[$wd, "."]> is specialcased - instead of failing,
		825	C<rmdir> is called on the absolute path of C<$wd>.
705		826
706		827
707	=item aio_readdir $pathname, $callback->($entries)	828	=item aio_readdir $pathname, $callback->($entries)
708		829
709	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire	830	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire
…		…
1074	}	1195	}
1075		1196
1076	=item aio_rmtree $pathname, $callback->($status)	1197	=item aio_rmtree $pathname, $callback->($status)
1077		1198
1078	Delete a directory tree starting (and including) C<$path>, return the	1199	Delete a directory tree starting (and including) C<$path>, return the
1079	status of the final C<rmdir> only. This is a composite request that	1200	status of the final C<rmdir> only. This is a composite request that
1080	uses C<aio_scandir> to recurse into and rmdir directories, and unlink	1201	uses C<aio_scandir> to recurse into and rmdir directories, and unlink
1081	everything else.	1202	everything else.
1082		1203
1083	=cut	1204	=cut
1084		1205
…		…
1204		1325
1205	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1326	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
1206	scalars.	1327	scalars.
1207		1328
1208	It touches (reads or writes) all memory pages in the specified	1329	It touches (reads or writes) all memory pages in the specified
1209	range inside the scalar. All caveats and parameters are the same	1330	range inside the scalar. All caveats and parameters are the same
1210	as for C<aio_msync>, above, except for flags, which must be either	1331	as for C<aio_msync>, above, except for flags, which must be either
1211	C<0> (which reads all pages and ensures they are instantiated) or	1332	C<0> (which reads all pages and ensures they are instantiated) or
1212	C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and	1333	C<IO::AIO::MT_MODIFY>, which modifies the memory pages (by reading and
1213	writing an octet from it, which dirties the page).	1334	writing an octet from it, which dirties the page).
1214		1335
1215	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)	1336	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
1216		1337
1217	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1338	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
…		…
1248	documented under L<MISCELLANEOUS FUNCTIONS>.	1369	documented under L<MISCELLANEOUS FUNCTIONS>.
1249		1370
1250	Example: asynchronously lock all current and future pages into memory.	1371	Example: asynchronously lock all current and future pages into memory.
1251		1372
1252	aio_mlockall IO::AIO::MCL_FUTURE;	1373	aio_mlockall IO::AIO::MCL_FUTURE;
		1374
		1375	=item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
		1376
		1377	Queries the extents of the given file (by calling the Linux C<FIEMAP>
		1378	ioctl, see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If
		1379	the ioctl is not available on your OS, then this request will fail with
		1380	C<ENOSYS>.
		1381
		1382	C<$start> is the starting offset to query extents for, C<$length> is the
		1383	size of the range to query - if it is C<undef>, then the whole file will
		1384	be queried.
		1385
		1386	C<$flags> is a combination of flags (C<IO::AIO::FIEMAP_FLAG_SYNC> or
		1387	C<IO::AIO::FIEMAP_FLAG_XATTR> - C<IO::AIO::FIEMAP_FLAGS_COMPAT> is also
		1388	exported), and is normally C<0> or C<IO::AIO::FIEMAP_FLAG_SYNC> to query
		1389	the data portion.
		1390
		1391	C<$count> is the maximum number of extent records to return. If it is
		1392	C<undef>, then IO::AIO queries all extents of the range. As a very special
		1393	case, if it is C<0>, then the callback receives the number of extents
		1394	instead of the extents themselves (which is unreliable, see below).
		1395
		1396	If an error occurs, the callback receives no arguments. The special
		1397	C<errno> value C<IO::AIO::EBADR> is available to test for flag errors.
		1398
		1399	Otherwise, the callback receives an array reference with extent
		1400	structures. Each extent structure is an array reference itself, with the
		1401	following members:
		1402
		1403	[$logical, $physical, $length, $flags]
		1404
		1405	Flags is any combination of the following flag values (typically either C<0>
		1406	or C<IO::AIO::FIEMAP_EXTENT_LAST> (1)):
		1407
		1408	C<IO::AIO::FIEMAP_EXTENT_LAST>, C<IO::AIO::FIEMAP_EXTENT_UNKNOWN>,
		1409	C<IO::AIO::FIEMAP_EXTENT_DELALLOC>, C<IO::AIO::FIEMAP_EXTENT_ENCODED>,
		1410	C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>,
		1411	C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>,
		1412	C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or
		1413	C<IO::AIO::FIEMAP_EXTENT_SHARED>.
		1414
		1415	At the time of this writing (Linux 3.2), this requets is unreliable unless
		1416	C<$count> is C<undef>, as the kernel has all sorts of bugs preventing
		1417	it to return all extents of a range for files with large number of
		1418	extents. The code works around all these issues if C<$count> is undef.
1253		1419
1254	=item aio_group $callback->(...)	1420	=item aio_group $callback->(...)
1255		1421
1256	This is a very special aio request: Instead of doing something, it is a	1422	This is a very special aio request: Instead of doing something, it is a
1257	container for other aio requests, which is useful if you want to bundle	1423	container for other aio requests, which is useful if you want to bundle
…		…
1341	aio_stat [$etcdir, "passwd"], sub {	1507	aio_stat [$etcdir, "passwd"], sub {
1342	# yay	1508	# yay
1343	};	1509	};
1344	};	1510	};
1345		1511
1346	That C<aio_wd> is a request and not a normal function shows that creating	1512	The fact that C<aio_wd> is a request and not a normal function shows that
1347	an IO::AIO::WD object is itself a potentially blocking operation, which is	1513	creating an IO::AIO::WD object is itself a potentially blocking operation,
1348	why it is done asynchronously.	1514	which is why it is done asynchronously.
1349		1515
1350	To stat the directory obtained with C<aio_wd> above, one could write	1516	To stat the directory obtained with C<aio_wd> above, one could write
1351	either of the following three request calls:	1517	either of the following three request calls:
1352		1518
1353	aio_lstat "/etc" , sub { ... # pathname as normal string	1519	aio_lstat "/etc" , sub { ... # pathname as normal string
…		…
1373	will still point to the original directory. Most functions accepting a	1539	will still point to the original directory. Most functions accepting a
1374	pathname will use the directory fd on newer systems, and the string on	1540	pathname will use the directory fd on newer systems, and the string on
1375	older systems. Some functions (such as realpath) will always rely on the	1541	older systems. Some functions (such as realpath) will always rely on the
1376	string form of the pathname.	1542	string form of the pathname.
1377		1543
1378	So this fucntionality is mainly useful to get some protection against	1544	So this functionality is mainly useful to get some protection against
1379	C<chdir>, to easily get an absolute path out of a relative path for future	1545	C<chdir>, to easily get an absolute path out of a relative path for future
1380	reference, and to speed up doing many operations in the same directory	1546	reference, and to speed up doing many operations in the same directory
1381	(e.g. when stat'ing all files in a directory).	1547	(e.g. when stat'ing all files in a directory).
1382		1548
1383	The following functions implement this working directory abstraction:	1549	The following functions implement this working directory abstraction:
…		…
1396	passing C<undef> as working directory component of a pathname fails the	1562	passing C<undef> as working directory component of a pathname fails the
1397	request with C<ENOENT>, there is often no need for error checking in the	1563	request with C<ENOENT>, there is often no need for error checking in the
1398	C<aio_wd> callback, as future requests using the value will fail in the	1564	C<aio_wd> callback, as future requests using the value will fail in the
1399	expected way.	1565	expected way.
1400		1566
1401	If this call isn't available because your OS lacks it or it couldn't be
1402	detected, it will be emulated by calling C<fsync> instead.
1403
1404	=item IO::AIO::CWD	1567	=item IO::AIO::CWD
1405		1568
1406	This is a compiletime constant (object) that represents the process	1569	This is a compiletime constant (object) that represents the process
1407	current working directory.	1570	current working directory.
1408		1571
1409	Specifying this object as working directory object for a pathname is as	1572	Specifying this object as working directory object for a pathname is as if
1410	if the pathname would be specified directly, without a directory object,	1573	the pathname would be specified directly, without a directory object. For
1411	e.g., these calls are functionally identical:	1574	example, these calls are functionally identical:
1412		1575
1413	aio_stat "somefile", sub { ... };	1576	aio_stat "somefile", sub { ... };
1414	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };	1577	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };
1415		1578
1416	=back	1579	=back
1417		1580
		1581	To recover the path associated with an IO::AIO::WD object, you can use
		1582	C<aio_realpath>:
		1583
		1584	aio_realpath $wd, sub {
		1585	warn "path is $_[0]\n";
		1586	};
		1587
		1588	Currently, C<aio_statvfs> always, and C<aio_rename> and C<aio_rmdir>
		1589	sometimes, fall back to using an absolue path.
1418		1590
1419	=head2 IO::AIO::REQ CLASS	1591	=head2 IO::AIO::REQ CLASS
1420		1592
1421	All non-aggregate C<aio_*> functions return an object of this class when	1593	All non-aggregate C<aio_*> functions return an object of this class when
1422	called in non-void context.	1594	called in non-void context.
…		…
1600		1772
1601	See C<poll_cb> for an example.	1773	See C<poll_cb> for an example.
1602		1774
1603	=item IO::AIO::poll_cb	1775	=item IO::AIO::poll_cb
1604		1776
1605	Process some outstanding events on the result pipe. You have to call	1777	Process some requests that have reached the result phase (i.e. they have
		1778	been executed but the results are not yet reported). You have to call
		1779	this "regularly" to finish outstanding requests.
		1780
1606	this regularly. Returns C<0> if all events could be processed (or there	1781	Returns C<0> if all events could be processed (or there were no
1607	were no events to process), or C<-1> if it returned earlier for whatever	1782	events to process), or C<-1> if it returned earlier for whatever
1608	reason. Returns immediately when no events are outstanding. The amount of	1783	reason. Returns immediately when no events are outstanding. The amount
1609	events processed depends on the settings of C<IO::AIO::max_poll_req> and	1784	of events processed depends on the settings of C<IO::AIO::max_poll_req>,
1610	C<IO::AIO::max_poll_time>.	1785	C<IO::AIO::max_poll_time> and C<IO::AIO::max_outstanding>.
1611		1786
1612	If not all requests were processed for whatever reason, the filehandle	1787	If not all requests were processed for whatever reason, the poll file
1613	will still be ready when C<poll_cb> returns, so normally you don't have to	1788	descriptor will still be ready when C<poll_cb> returns, so normally you
1614	do anything special to have it called later.	1789	don't have to do anything special to have it called later.
1615		1790
1616	Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes	1791	Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes
1617	ready, it can be beneficial to call this function from loops which submit	1792	ready, it can be beneficial to call this function from loops which submit
1618	a lot of requests, to make sure the results get processed when they become	1793	a lot of requests, to make sure the results get processed when they become
1619	available and not just when the loop is finished and the event loop takes	1794	available and not just when the loop is finished and the event loop takes
…		…
1628	poll => 'r', async => 1,	1803	poll => 'r', async => 1,
1629	cb => \&IO::AIO::poll_cb);	1804	cb => \&IO::AIO::poll_cb);
1630		1805
1631	=item IO::AIO::poll_wait	1806	=item IO::AIO::poll_wait
1632		1807
1633	If there are any outstanding requests and none of them in the result	1808	Wait until either at least one request is in the result phase or no
1634	phase, wait till the result filehandle becomes ready for reading (simply	1809	requests are outstanding anymore.
1635	does a C<select> on the filehandle. This is useful if you want to	1810
1636	synchronously wait for some requests to finish).	1811	This is useful if you want to synchronously wait for some requests to
		1812	become ready, without actually handling them.
1637		1813
1638	See C<nreqs> for an example.	1814	See C<nreqs> for an example.
1639		1815
1640	=item IO::AIO::poll	1816	=item IO::AIO::poll
1641		1817
…		…
1762		1938
1763	This is a very bad function to use in interactive programs because it	1939	This is a very bad function to use in interactive programs because it
1764	blocks, and a bad way to reduce concurrency because it is inexact: Better	1940	blocks, and a bad way to reduce concurrency because it is inexact: Better
1765	use an C<aio_group> together with a feed callback.	1941	use an C<aio_group> together with a feed callback.
1766		1942
1767	It's main use is in scripts without an event loop - when you want to stat	1943	Its main use is in scripts without an event loop - when you want to stat
1768	a lot of files, you can write somehting like this:	1944	a lot of files, you can write somehting like this:
1769		1945
1770	IO::AIO::max_outstanding 32;	1946	IO::AIO::max_outstanding 32;
1771		1947
1772	for my $path (...) {	1948	for my $path (...) {
…		…
1812		1988
1813	=back	1989	=back
1814		1990
1815	=head3 MISCELLANEOUS FUNCTIONS	1991	=head3 MISCELLANEOUS FUNCTIONS
1816		1992
1817	IO::AIO implements some functions that might be useful, but are not	1993	IO::AIO implements some functions that are useful when you want to use
1818	asynchronous.	1994	some "Advanced I/O" function not available to in Perl, without going the
		1995	"Asynchronous I/O" route. Many of these have an asynchronous C<aio_*>
		1996	counterpart.
1819		1997
1820	=over 4	1998	=over 4
1821		1999
1822	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count	2000	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
1823		2001
…		…
1860	ENOSYS, otherwise the return value of C<mprotect>.	2038	ENOSYS, otherwise the return value of C<mprotect>.
1861		2039
1862	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]	2040	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]
1863		2041
1864	Memory-maps a file (or anonymous memory range) and attaches it to the	2042	Memory-maps a file (or anonymous memory range) and attaches it to the
1865	given C<$scalar>, which will act like a string scalar.	2043	given C<$scalar>, which will act like a string scalar. Returns true on
		2044	success, and false otherwise.
1866		2045
1867	The only operations allowed on the scalar are C<substr>/C<vec> that don't	2046	The only operations allowed on the scalar are C<substr>/C<vec> that don't
1868	change the string length, and most read-only operations such as copying it	2047	change the string length, and most read-only operations such as copying it
1869	or searching it with regexes and so on.	2048	or searching it with regexes and so on.
1870		2049
…		…
1881	filesize.	2060	filesize.
1882		2061
1883	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,	2062	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,
1884	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,	2063	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,
1885		2064
1886	C<$flags> can be a combination of C<IO::AIO::MAP_SHARED> or	2065	C<$flags> can be a combination of
1887	C<IO::AIO::MAP_PRIVATE>, or a number of system-specific flags (when	2066	C<IO::AIO::MAP_SHARED> or
1888	not available, the are defined as 0): C<IO::AIO::MAP_ANONYMOUS>	2067	C<IO::AIO::MAP_PRIVATE>,
		2068	or a number of system-specific flags (when not available, the are C<0>):
1889	(which is set to C<MAP_ANON> if your system only provides this	2069	C<IO::AIO::MAP_ANONYMOUS> (which is set to C<MAP_ANON> if your system only provides this constant),
1890	constant), C<IO::AIO::MAP_HUGETLB>, C<IO::AIO::MAP_LOCKED>,	2070	C<IO::AIO::MAP_LOCKED>,
1891	C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or	2071	C<IO::AIO::MAP_NORESERVE>,
		2072	C<IO::AIO::MAP_POPULATE>,
1892	C<IO::AIO::MAP_NONBLOCK>	2073	C<IO::AIO::MAP_NONBLOCK>,
		2074	C<IO::AIO::MAP_FIXED>,
		2075	C<IO::AIO::MAP_GROWSDOWN>,
		2076	C<IO::AIO::MAP_32BIT>,
		2077	C<IO::AIO::MAP_HUGETLB> or
		2078	C<IO::AIO::MAP_STACK>.
1893		2079
1894	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.	2080	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.
1895		2081
1896	C<$offset> is the offset from the start of the file - it generally must be	2082	C<$offset> is the offset from the start of the file - it generally must be
1897	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.	2083	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.
…		…
1922		2108
1923	Calls the C<munlockall> function.	2109	Calls the C<munlockall> function.
1924		2110
1925	On systems that do not implement C<munlockall>, this function returns	2111	On systems that do not implement C<munlockall>, this function returns
1926	ENOSYS, otherwise the return value of C<munlockall>.	2112	ENOSYS, otherwise the return value of C<munlockall>.
		2113
		2114	=item IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags
		2115
		2116	Calls the GNU/Linux C<splice(2)> syscall, if available. If C<$r_off> or
		2117	C<$w_off> are C<undef>, then C<NULL> is passed for these, otherwise they
		2118	should be the file offset.
		2119
		2120	C<$r_fh> and C<$w_fh> should not refer to the same file, as splice might
		2121	silently corrupt the data in this case.
		2122
		2123	The following symbol flag values are available: C<IO::AIO::SPLICE_F_MOVE>,
		2124	C<IO::AIO::SPLICE_F_NONBLOCK>, C<IO::AIO::SPLICE_F_MORE> and
		2125	C<IO::AIO::SPLICE_F_GIFT>.
		2126
		2127	See the C<splice(2)> manpage for details.
		2128
		2129	=item IO::AIO::tee $r_fh, $w_fh, $length, $flags
		2130
		2131	Calls the GNU/Linux C<tee(2)> syscall, see its manpage and the
		2132	description for C<IO::AIO::splice> above for details.
		2133
		2134	=item $actual_size = IO::AIO::pipesize $r_fh[, $new_size]
		2135
		2136	Attempts to query or change the pipe buffer size. Obviously works only
		2137	on pipes, and currently works only on GNU/Linux systems, and fails with
		2138	C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer
		2139	size on other systems, drop me a note.
		2140
		2141	=item ($rfh, $wfh) = IO::AIO::pipe2 [$flags]
		2142
		2143	This is a direct interface to the Linux L<pipe2(2)> system call. If
		2144	C<$flags> is missing or C<0>, then this should be the same as a call to
		2145	perl's built-in C<pipe> function and create a new pipe, and works on
		2146	systems that lack the pipe2 syscall. On win32, this case invokes C<_pipe
		2147	(..., 4096, O_BINARY)>.
		2148
		2149	If C<$flags> is non-zero, it tries to invoke the pipe2 system call with
		2150	the given flags (Linux 2.6.27, glibc 2.9).
		2151
		2152	On success, the read and write file handles are returned.
		2153
		2154	On error, nothing will be returned. If the pipe2 syscall is missing and
		2155	C<$flags> is non-zero, fails with C<ENOSYS>.
		2156
		2157	Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the
		2158	time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and
		2159	C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported.
1927		2160
1928	=back	2161	=back
1929		2162
1930	=cut	2163	=cut
1931		2164

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Comparing IO-AIO/AIO.pm (file contents): Revision 1.220 by root, Sun Apr 1 17:46:02 2012 UTC vs. Revision 1.258 by root, Thu Jan 21 23:04:46 2016 UTC

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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.220 by root, Sun Apr 1 17:46:02 2012 UTC vs.
Revision 1.258 by root, Thu Jan 21 23:04:46 2016 UTC