[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 1.253 by root, Thu Jun 25 13:34:28 2015 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;
…		…
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 = 4.32;
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
…		…
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
		632	0x0000ef51 ext2
		633	0x00004006 fat
		634	0x65735546 fuseblk
		635	0x65735543 fusectl
		636	0x0bad1dea futexfs
		637	0x01161970 gfs2
		638	0x47504653 gpfs
		639	0x00004244 hfs
		640	0xf995e849 hpfs
		641	0x958458f6 hugetlbfs
		642	0x2bad1dea inotifyfs
		643	0x00009660 isofs
		644	0x000072b6 jffs2
		645	0x3153464a jfs
		646	0x6b414653 k-afs
		647	0x0bd00bd0 lustre
		648	0x0000137f minix
		649	0x0000138f minix 30 char names
		650	0x00002468 minix v2
		651	0x00002478 minix v2 30 char names
		652	0x00004d5a minix v3
		653	0x19800202 mqueue
		654	0x00004d44 msdos
		655	0x0000564c novell
		656	0x00006969 nfs
		657	0x6e667364 nfsd
		658	0x00003434 nilfs
		659	0x5346544e ntfs
		660	0x00009fa1 openprom
		661	0x7461636F ocfs2
		662	0x00009fa0 proc
		663	0x6165676c pstorefs
		664	0x0000002f qnx4
		665	0x858458f6 ramfs
		666	0x52654973 reiserfs
		667	0x00007275 romfs
		668	0x67596969 rpc_pipefs
		669	0x73636673 securityfs
		670	0xf97cff8c selinux
		671	0x0000517b smb
		672	0x534f434b sockfs
		673	0x73717368 squashfs
		674	0x62656572 sysfs
		675	0x012ff7b6 sysv2
		676	0x012ff7b5 sysv4
		677	0x01021994 tmpfs
		678	0x15013346 udf
		679	0x00011954 ufs
		680	0x54190100 ufs byteswapped
		681	0x00009fa2 usbdevfs
		682	0x01021997 v9fs
		683	0xa501fcf5 vxfs
		684	0xabba1974 xenfs
		685	0x012ff7b4 xenix
		686	0x58465342 xfs
		687	0x012fd16d xia
598		688
599	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	689	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
600		690
601	Works like perl's C<utime> function (including the special case of $atime	691	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	692	and $mtime being undef). Fractional times are supported if the underlying
…		…
630	=item aio_truncate $fh_or_path, $offset, $callback->($status)	720	=item aio_truncate $fh_or_path, $offset, $callback->($status)
631		721
632	Works like truncate(2) or ftruncate(2).	722	Works like truncate(2) or ftruncate(2).
633		723
634		724
		725	=item aio_allocate $fh, $mode, $offset, $len, $callback->($status)
		726
		727	Allocates or frees disk space according to the C<$mode> argument. See the
		728	linux C<fallocate> documentation for details.
		729
		730	C<$mode> is usually C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> to allocate
		731	space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE \| IO::AIO::FALLOC_FL_KEEP_SIZE>,
		732	to deallocate a file range.
		733
		734	IO::AIO also supports C<FALLOC_FL_COLLAPSE_RANGE>, to remove a range
		735	(without leaving a hole) and C<FALLOC_FL_ZERO_RANGE>, to zero a range (see
		736	your L<fallocate(2)> manpage).
		737
		738	The file system block size used by C<fallocate> is presumably the
		739	C<f_bsize> returned by C<statvfs>.
		740
		741	If C<fallocate> isn't available or cannot be emulated (currently no
		742	emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>.
		743
		744
635	=item aio_chmod $fh_or_path, $mode, $callback->($status)	745	=item aio_chmod $fh_or_path, $mode, $callback->($status)
636		746
637	Works like perl's C<chmod> function.	747	Works like perl's C<chmod> function.
638		748
639		749
…		…
676		786
677		787
678	=item aio_realpath $pathname, $callback->($path)	788	=item aio_realpath $pathname, $callback->($path)
679		789
680	Asynchronously make the path absolute and resolve any symlinks in	790	Asynchronously make the path absolute and resolve any symlinks in
681	C<$path>. The resulting path only consists of directories (Same as	791	C<$path>. The resulting path only consists of directories (same as
682	L<Cwd::realpath>).	792	L<Cwd::realpath>).
683		793
684	This request can be used to get the absolute path of the current working	794	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).	795	directory by passing it a path of F<.> (a single dot).
686		796
687		797
688	=item aio_rename $srcpath, $dstpath, $callback->($status)	798	=item aio_rename $srcpath, $dstpath, $callback->($status)
689		799
690	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as	800	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as
691	rename(2) and call the callback with the result code.	801	rename(2) and call the callback with the result code.
		802
		803	On systems that support the AIO::WD working directory abstraction
		804	natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead
		805	of failing, C<rename> is called on the absolute path of C<$wd>.
692		806
693		807
694	=item aio_mkdir $pathname, $mode, $callback->($status)	808	=item aio_mkdir $pathname, $mode, $callback->($status)
695		809
696	Asynchronously mkdir (create) a directory and call the callback with	810	Asynchronously mkdir (create) a directory and call the callback with
…		…
700		814
701	=item aio_rmdir $pathname, $callback->($status)	815	=item aio_rmdir $pathname, $callback->($status)
702		816
703	Asynchronously rmdir (delete) a directory and call the callback with the	817	Asynchronously rmdir (delete) a directory and call the callback with the
704	result code.	818	result code.
		819
		820	On systems that support the AIO::WD working directory abstraction
		821	natively, the case C<[$wd, "."]> is specialcased - instead of failing,
		822	C<rmdir> is called on the absolute path of C<$wd>.
705		823
706		824
707	=item aio_readdir $pathname, $callback->($entries)	825	=item aio_readdir $pathname, $callback->($entries)
708		826
709	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire	827	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire
…		…
1074	}	1192	}
1075		1193
1076	=item aio_rmtree $pathname, $callback->($status)	1194	=item aio_rmtree $pathname, $callback->($status)
1077		1195
1078	Delete a directory tree starting (and including) C<$path>, return the	1196	Delete a directory tree starting (and including) C<$path>, return the
1079	status of the final C<rmdir> only. This is a composite request that	1197	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	1198	uses C<aio_scandir> to recurse into and rmdir directories, and unlink
1081	everything else.	1199	everything else.
1082		1200
1083	=cut	1201	=cut
1084		1202
…		…
1204		1322
1205	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1323	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
1206	scalars.	1324	scalars.
1207		1325
1208	It touches (reads or writes) all memory pages in the specified	1326	It touches (reads or writes) all memory pages in the specified
1209	range inside the scalar. All caveats and parameters are the same	1327	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	1328	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	1329	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	1330	C<IO::AIO::MT_MODIFY>, which modifies the memory pages (by reading and
1213	writing an octet from it, which dirties the page).	1331	writing an octet from it, which dirties the page).
1214		1332
1215	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)	1333	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
1216		1334
1217	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1335	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
…		…
1248	documented under L<MISCELLANEOUS FUNCTIONS>.	1366	documented under L<MISCELLANEOUS FUNCTIONS>.
1249		1367
1250	Example: asynchronously lock all current and future pages into memory.	1368	Example: asynchronously lock all current and future pages into memory.
1251		1369
1252	aio_mlockall IO::AIO::MCL_FUTURE;	1370	aio_mlockall IO::AIO::MCL_FUTURE;
		1371
		1372	=item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
		1373
		1374	Queries the extents of the given file (by calling the Linux C<FIEMAP>
		1375	ioctl, see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If
		1376	the ioctl is not available on your OS, then this request will fail with
		1377	C<ENOSYS>.
		1378
		1379	C<$start> is the starting offset to query extents for, C<$length> is the
		1380	size of the range to query - if it is C<undef>, then the whole file will
		1381	be queried.
		1382
		1383	C<$flags> is a combination of flags (C<IO::AIO::FIEMAP_FLAG_SYNC> or
		1384	C<IO::AIO::FIEMAP_FLAG_XATTR> - C<IO::AIO::FIEMAP_FLAGS_COMPAT> is also
		1385	exported), and is normally C<0> or C<IO::AIO::FIEMAP_FLAG_SYNC> to query
		1386	the data portion.
		1387
		1388	C<$count> is the maximum number of extent records to return. If it is
		1389	C<undef>, then IO::AIO queries all extents of the range. As a very special
		1390	case, if it is C<0>, then the callback receives the number of extents
		1391	instead of the extents themselves (which is unreliable, see below).
		1392
		1393	If an error occurs, the callback receives no arguments. The special
		1394	C<errno> value C<IO::AIO::EBADR> is available to test for flag errors.
		1395
		1396	Otherwise, the callback receives an array reference with extent
		1397	structures. Each extent structure is an array reference itself, with the
		1398	following members:
		1399
		1400	[$logical, $physical, $length, $flags]
		1401
		1402	Flags is any combination of the following flag values (typically either C<0>
		1403	or C<IO::AIO::FIEMAP_EXTENT_LAST> (1)):
		1404
		1405	C<IO::AIO::FIEMAP_EXTENT_LAST>, C<IO::AIO::FIEMAP_EXTENT_UNKNOWN>,
		1406	C<IO::AIO::FIEMAP_EXTENT_DELALLOC>, C<IO::AIO::FIEMAP_EXTENT_ENCODED>,
		1407	C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>,
		1408	C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>,
		1409	C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or
		1410	C<IO::AIO::FIEMAP_EXTENT_SHARED>.
		1411
		1412	At the time of this writing (Linux 3.2), this requets is unreliable unless
		1413	C<$count> is C<undef>, as the kernel has all sorts of bugs preventing
		1414	it to return all extents of a range for files with large number of
		1415	extents. The code works around all these issues if C<$count> is undef.
1253		1416
1254	=item aio_group $callback->(...)	1417	=item aio_group $callback->(...)
1255		1418
1256	This is a very special aio request: Instead of doing something, it is a	1419	This is a very special aio request: Instead of doing something, it is a
1257	container for other aio requests, which is useful if you want to bundle	1420	container for other aio requests, which is useful if you want to bundle
…		…
1341	aio_stat [$etcdir, "passwd"], sub {	1504	aio_stat [$etcdir, "passwd"], sub {
1342	# yay	1505	# yay
1343	};	1506	};
1344	};	1507	};
1345		1508
1346	That C<aio_wd> is a request and not a normal function shows that creating	1509	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	1510	creating an IO::AIO::WD object is itself a potentially blocking operation,
1348	why it is done asynchronously.	1511	which is why it is done asynchronously.
1349		1512
1350	To stat the directory obtained with C<aio_wd> above, one could write	1513	To stat the directory obtained with C<aio_wd> above, one could write
1351	either of the following three request calls:	1514	either of the following three request calls:
1352		1515
1353	aio_lstat "/etc" , sub { ... # pathname as normal string	1516	aio_lstat "/etc" , sub { ... # pathname as normal string
…		…
1373	will still point to the original directory. Most functions accepting a	1536	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	1537	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	1538	older systems. Some functions (such as realpath) will always rely on the
1376	string form of the pathname.	1539	string form of the pathname.
1377		1540
1378	So this fucntionality is mainly useful to get some protection against	1541	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	1542	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	1543	reference, and to speed up doing many operations in the same directory
1381	(e.g. when stat'ing all files in a directory).	1544	(e.g. when stat'ing all files in a directory).
1382		1545
1383	The following functions implement this working directory abstraction:	1546	The following functions implement this working directory abstraction:
…		…
1396	passing C<undef> as working directory component of a pathname fails the	1559	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	1560	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	1561	C<aio_wd> callback, as future requests using the value will fail in the
1399	expected way.	1562	expected way.
1400		1563
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	1564	=item IO::AIO::CWD
1405		1565
1406	This is a compiletime constant (object) that represents the process	1566	This is a compiletime constant (object) that represents the process
1407	current working directory.	1567	current working directory.
1408		1568
1409	Specifying this object as working directory object for a pathname is as	1569	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,	1570	the pathname would be specified directly, without a directory object. For
1411	e.g., these calls are functionally identical:	1571	example, these calls are functionally identical:
1412		1572
1413	aio_stat "somefile", sub { ... };	1573	aio_stat "somefile", sub { ... };
1414	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };	1574	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };
1415		1575
1416	=back	1576	=back
1417		1577
		1578	To recover the path associated with an IO::AIO::WD object, you can use
		1579	C<aio_realpath>:
		1580
		1581	aio_realpath $wd, sub {
		1582	warn "path is $_[0]\n";
		1583	};
		1584
		1585	Currently, C<aio_statvfs> always, and C<aio_rename> and C<aio_rmdir>
		1586	sometimes, fall back to using an absolue path.
1418		1587
1419	=head2 IO::AIO::REQ CLASS	1588	=head2 IO::AIO::REQ CLASS
1420		1589
1421	All non-aggregate C<aio_*> functions return an object of this class when	1590	All non-aggregate C<aio_*> functions return an object of this class when
1422	called in non-void context.	1591	called in non-void context.
…		…
1600		1769
1601	See C<poll_cb> for an example.	1770	See C<poll_cb> for an example.
1602		1771
1603	=item IO::AIO::poll_cb	1772	=item IO::AIO::poll_cb
1604		1773
1605	Process some outstanding events on the result pipe. You have to call	1774	Process some requests that have reached the result phase (i.e. they have
		1775	been executed but the results are not yet reported). You have to call
		1776	this "regularly" to finish outstanding requests.
		1777
1606	this regularly. Returns C<0> if all events could be processed (or there	1778	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	1779	events to process), or C<-1> if it returned earlier for whatever
1608	reason. Returns immediately when no events are outstanding. The amount of	1780	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	1781	of events processed depends on the settings of C<IO::AIO::max_poll_req>,
1610	C<IO::AIO::max_poll_time>.	1782	C<IO::AIO::max_poll_time> and C<IO::AIO::max_outstanding>.
1611		1783
1612	If not all requests were processed for whatever reason, the filehandle	1784	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	1785	descriptor will still be ready when C<poll_cb> returns, so normally you
1614	do anything special to have it called later.	1786	don't have to do anything special to have it called later.
1615		1787
1616	Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes	1788	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	1789	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	1790	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	1791	available and not just when the loop is finished and the event loop takes
…		…
1628	poll => 'r', async => 1,	1800	poll => 'r', async => 1,
1629	cb => \&IO::AIO::poll_cb);	1801	cb => \&IO::AIO::poll_cb);
1630		1802
1631	=item IO::AIO::poll_wait	1803	=item IO::AIO::poll_wait
1632		1804
1633	If there are any outstanding requests and none of them in the result	1805	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	1806	requests are outstanding anymore.
1635	does a C<select> on the filehandle. This is useful if you want to	1807
1636	synchronously wait for some requests to finish).	1808	This is useful if you want to synchronously wait for some requests to
		1809	become ready, without actually handling them.
1637		1810
1638	See C<nreqs> for an example.	1811	See C<nreqs> for an example.
1639		1812
1640	=item IO::AIO::poll	1813	=item IO::AIO::poll
1641		1814
…		…
1762		1935
1763	This is a very bad function to use in interactive programs because it	1936	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	1937	blocks, and a bad way to reduce concurrency because it is inexact: Better
1765	use an C<aio_group> together with a feed callback.	1938	use an C<aio_group> together with a feed callback.
1766		1939
1767	It's main use is in scripts without an event loop - when you want to stat	1940	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:	1941	a lot of files, you can write somehting like this:
1769		1942
1770	IO::AIO::max_outstanding 32;	1943	IO::AIO::max_outstanding 32;
1771		1944
1772	for my $path (...) {	1945	for my $path (...) {
…		…
1812		1985
1813	=back	1986	=back
1814		1987
1815	=head3 MISCELLANEOUS FUNCTIONS	1988	=head3 MISCELLANEOUS FUNCTIONS
1816		1989
1817	IO::AIO implements some functions that might be useful, but are not	1990	IO::AIO implements some functions that are useful when you want to use
1818	asynchronous.	1991	some "Advanced I/O" function not available to in Perl, without going the
		1992	"Asynchronous I/O" route. Many of these have an asynchronous C<aio_*>
		1993	counterpart.
1819		1994
1820	=over 4	1995	=over 4
1821		1996
1822	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count	1997	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
1823		1998
…		…
1860	ENOSYS, otherwise the return value of C<mprotect>.	2035	ENOSYS, otherwise the return value of C<mprotect>.
1861		2036
1862	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]	2037	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]
1863		2038
1864	Memory-maps a file (or anonymous memory range) and attaches it to the	2039	Memory-maps a file (or anonymous memory range) and attaches it to the
1865	given C<$scalar>, which will act like a string scalar.	2040	given C<$scalar>, which will act like a string scalar. Returns true on
		2041	success, and false otherwise.
1866		2042
1867	The only operations allowed on the scalar are C<substr>/C<vec> that don't	2043	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	2044	change the string length, and most read-only operations such as copying it
1869	or searching it with regexes and so on.	2045	or searching it with regexes and so on.
1870		2046
…		…
1923	Calls the C<munlockall> function.	2099	Calls the C<munlockall> function.
1924		2100
1925	On systems that do not implement C<munlockall>, this function returns	2101	On systems that do not implement C<munlockall>, this function returns
1926	ENOSYS, otherwise the return value of C<munlockall>.	2102	ENOSYS, otherwise the return value of C<munlockall>.
1927		2103
		2104	=item IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags
		2105
		2106	Calls the GNU/Linux C<splice(2)> syscall, if available. If C<$r_off> or
		2107	C<$w_off> are C<undef>, then C<NULL> is passed for these, otherwise they
		2108	should be the file offset.
		2109
		2110	C<$r_fh> and C<$w_fh> should not refer to the same file, as splice might
		2111	silently corrupt the data in this case.
		2112
		2113	The following symbol flag values are available: C<IO::AIO::SPLICE_F_MOVE>,
		2114	C<IO::AIO::SPLICE_F_NONBLOCK>, C<IO::AIO::SPLICE_F_MORE> and
		2115	C<IO::AIO::SPLICE_F_GIFT>.
		2116
		2117	See the C<splice(2)> manpage for details.
		2118
		2119	=item IO::AIO::tee $r_fh, $w_fh, $length, $flags
		2120
		2121	Calls the GNU/Linux C<tee(2)> syscall, see its manpage and the
		2122	description for C<IO::AIO::splice> above for details.
		2123
		2124	=item $actual_size = IO::AIO::pipesize $r_fh[, $new_size]
		2125
		2126	Attempts to query or change the pipe buffer size. Obviously works only
		2127	on pipes, and currently works only on GNU/Linux systems, and fails with
		2128	C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer
		2129	size on other systems, drop me a note.
		2130
		2131	=item ($rfh, $wfh) = IO::AIO::pipe2 [$flags]
		2132
		2133	This is a direct interface to the Linux L<pipe2(2)> system call. If
		2134	C<$flags> is missing or C<0>, then this should be the same as a call to
		2135	perl's built-in C<pipe> function and create a new pipe, and should work
		2136	everywhere.
		2137
		2138	If C<$flags> is non-zero, it tries to invoke the pipe2 system call with
		2139	the given flags (Linux 2.6.27, glibc 2.9).
		2140
		2141	On success, the read and write file handles are returned.
		2142
		2143	On error, nothing will be returned. If the pipe2 syscall is missing and
		2144	C<$flags> is non-zero, fails with C<ENOSYS>.
		2145
		2146	Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the
		2147	time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and
		2148	C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported.
		2149
1928	=back	2150	=back
1929		2151
1930	=cut	2152	=cut
1931		2153
1932	min_parallel 8;	2154	min_parallel 8;

Diff Legend

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

Comparing IO-AIO/AIO.pm (file contents): Revision 1.220 by root, Sun Apr 1 17:46:02 2012 UTC vs. Revision 1.253 by root, Thu Jun 25 13:34:28 2015 UTC

Diff Legend

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.220 by root, Sun Apr 1 17:46:02 2012 UTC vs.
Revision 1.253 by root, Thu Jun 25 13:34:28 2015 UTC