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

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.217 by root, Sun Oct 9 22:25:00 2011 UTC vs.
Revision 1.248 by root, Sun Jul 27 22:10:53 2014 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 = '4.11';	172	our $VERSION = 4.31;
174		173
175	our @AIO_REQ = qw(aio_sendfile 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)
		213	aio_seek $fh,$offset,$whence, $callback->($offs)
214	aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	214	aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
215	aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	215	aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
216	aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)	216	aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
217	aio_readahead $fh,$offset,$length, $callback->($retval)	217	aio_readahead $fh,$offset,$length, $callback->($retval)
218	aio_stat $fh_or_path, $callback->($status)	218	aio_stat $fh_or_path, $callback->($status)
219	aio_lstat $fh, $callback->($status)	219	aio_lstat $fh, $callback->($status)
220	aio_statvfs $fh_or_path, $callback->($statvfs)	220	aio_statvfs $fh_or_path, $callback->($statvfs)
221	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	221	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
222	aio_chown $fh_or_path, $uid, $gid, $callback->($status)	222	aio_chown $fh_or_path, $uid, $gid, $callback->($status)
		223	aio_chmod $fh_or_path, $mode, $callback->($status)
223	aio_truncate $fh_or_path, $offset, $callback->($status)	224	aio_truncate $fh_or_path, $offset, $callback->($status)
224	aio_chmod $fh_or_path, $mode, $callback->($status)	225	aio_allocate $fh, $mode, $offset, $len, $callback->($status)
		226	aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
225	aio_unlink $pathname, $callback->($status)	227	aio_unlink $pathname, $callback->($status)
226	aio_mknod $pathname, $mode, $dev, $callback->($status)	228	aio_mknod $pathname, $mode, $dev, $callback->($status)
227	aio_link $srcpath, $dstpath, $callback->($status)	229	aio_link $srcpath, $dstpath, $callback->($status)
228	aio_symlink $srcpath, $dstpath, $callback->($status)	230	aio_symlink $srcpath, $dstpath, $callback->($status)
229	aio_readlink $pathname, $callback->($link)	231	aio_readlink $pathname, $callback->($link)
…		…
271	IO::AIO::nready	273	IO::AIO::nready
272	IO::AIO::npending	274	IO::AIO::npending
273		275
274	IO::AIO::sendfile $ofh, $ifh, $offset, $count	276	IO::AIO::sendfile $ofh, $ifh, $offset, $count
275	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
276	IO::AIO::madvise $scalar, $offset, $length, $advice	280	IO::AIO::madvise $scalar, $offset, $length, $advice
277	IO::AIO::mprotect $scalar, $offset, $length, $protect	281	IO::AIO::mprotect $scalar, $offset, $length, $protect
278	IO::AIO::munlock $scalar, $offset = 0, $length = undef	282	IO::AIO::munlock $scalar, $offset = 0, $length = undef
279	IO::AIO::munlockall	283	IO::AIO::munlockall
280		284
281	=head2 AIO REQUEST FUNCTIONS	285	=head2 API NOTES
282		286
283	All the C<aio_*> calls are more or less thin wrappers around the syscall	287	All the C<aio_*> calls are more or less thin wrappers around the syscall
284	with the same name (sans C<aio_>). The arguments are similar or identical,	288	with the same name (sans C<aio_>). The arguments are similar or identical,
285	and they all accept an additional (and optional) C<$callback> argument	289	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	290	which must be a code reference. This code reference will be called after
…		…
317	correct contents.	321	correct contents.
318		322
319	This works, btw. independent of the internal UTF-8 bit, which IO::AIO	323	This works, btw. independent of the internal UTF-8 bit, which IO::AIO
320	handles correctly whether it is set or not.	324	handles correctly whether it is set or not.
321		325
		326	=head2 AIO REQUEST FUNCTIONS
		327
322	=over 4	328	=over 4
323		329
324	=item $prev_pri = aioreq_pri [$pri]	330	=item $prev_pri = aioreq_pri [$pri]
325		331
326	Returns the priority value that would be used for the next request and, if	332	Returns the priority value that would be used for the next request and, if
…		…
355		361
356		362
357	=item aio_open $pathname, $flags, $mode, $callback->($fh)	363	=item aio_open $pathname, $flags, $mode, $callback->($fh)
358		364
359	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
360	created filehandle for the file.	366	created filehandle for the file (or C<undef> in case of an error).
361		367
362	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,
363	for an explanation.	369	for an explanation.
364		370
365	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
…		…
407		413
408	Or in other words: the file descriptor will be closed, but it will not be	414	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.	415	free for reuse until the perl filehandle is closed.
410		416
411	=cut	417	=cut
		418
		419	=item aio_seek $fh, $offset, $whence, $callback->($offs)
		420
		421	Seeks the filehandle to the new C<$offset>, similarly to perl's
		422	C<sysseek>. The C<$whence> can use the traditional values (C<0> for
		423	C<IO::AIO::SEEK_SET>, C<1> for C<IO::AIO::SEEK_CUR> or C<2> for
		424	C<IO::AIO::SEEK_END>).
		425
		426	The resulting absolute offset will be passed to the callback, or C<-1> in
		427	case of an error.
		428
		429	In theory, the C<$whence> constants could be different than the
		430	corresponding values from L<Fcntl>, but perl guarantees they are the same,
		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".
412		438
413	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	439	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
414		440
415	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	441	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
416		442
…		…
576	namemax => 255,	602	namemax => 255,
577	frsize => 1024,	603	frsize => 1024,
578	fsid => 1810	604	fsid => 1810
579	}	605	}
580		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
581		688
582	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	689	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
583		690
584	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
585	and $mtime being undef). Fractional times are supported if the underlying	692	and $mtime being undef). Fractional times are supported if the underlying
…		…
613	=item aio_truncate $fh_or_path, $offset, $callback->($status)	720	=item aio_truncate $fh_or_path, $offset, $callback->($status)
614		721
615	Works like truncate(2) or ftruncate(2).	722	Works like truncate(2) or ftruncate(2).
616		723
617		724
		725	=item aio_allocate $fh, $mode, $offset, $len, $callback->($status)
		726
		727	Allocates or freed disk space according to the C<$mode> argument. See the
		728	linux C<fallocate> docuemntation for details.
		729
		730	C<$mode> can currently be C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE>
		731	to allocate space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE \|
		732	IO::AIO::FALLOC_FL_KEEP_SIZE>, to deallocate a file range.
		733
		734	The file system block size used by C<fallocate> is presumably the
		735	C<f_bsize> returned by C<statvfs>.
		736
		737	If C<fallocate> isn't available or cannot be emulated (currently no
		738	emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>.
		739
		740
618	=item aio_chmod $fh_or_path, $mode, $callback->($status)	741	=item aio_chmod $fh_or_path, $mode, $callback->($status)
619		742
620	Works like perl's C<chmod> function.	743	Works like perl's C<chmod> function.
621		744
622		745
…		…
659		782
660		783
661	=item aio_realpath $pathname, $callback->($path)	784	=item aio_realpath $pathname, $callback->($path)
662		785
663	Asynchronously make the path absolute and resolve any symlinks in	786	Asynchronously make the path absolute and resolve any symlinks in
664	C<$path>. The resulting path only consists of directories (Same as	787	C<$path>. The resulting path only consists of directories (same as
665	L<Cwd::realpath>).	788	L<Cwd::realpath>).
666		789
667	This request can be used to get the absolute path of the current working	790	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).	791	directory by passing it a path of F<.> (a single dot).
669		792
670		793
671	=item aio_rename $srcpath, $dstpath, $callback->($status)	794	=item aio_rename $srcpath, $dstpath, $callback->($status)
672		795
673	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as	796	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as
674	rename(2) and call the callback with the result code.	797	rename(2) and call the callback with the result code.
		798
		799	On systems that support the AIO::WD working directory abstraction
		800	natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead
		801	of failing, C<rename> is called on the absolute path of C<$wd>.
675		802
676		803
677	=item aio_mkdir $pathname, $mode, $callback->($status)	804	=item aio_mkdir $pathname, $mode, $callback->($status)
678		805
679	Asynchronously mkdir (create) a directory and call the callback with	806	Asynchronously mkdir (create) a directory and call the callback with
…		…
683		810
684	=item aio_rmdir $pathname, $callback->($status)	811	=item aio_rmdir $pathname, $callback->($status)
685		812
686	Asynchronously rmdir (delete) a directory and call the callback with the	813	Asynchronously rmdir (delete) a directory and call the callback with the
687	result code.	814	result code.
		815
		816	On systems that support the AIO::WD working directory abstraction
		817	natively, the case C<[$wd, "."]> is specialcased - instead of failing,
		818	C<rmdir> is called on the absolute path of C<$wd>.
688		819
689		820
690	=item aio_readdir $pathname, $callback->($entries)	821	=item aio_readdir $pathname, $callback->($entries)
691		822
692	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire	823	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire
…		…
1057	}	1188	}
1058		1189
1059	=item aio_rmtree $pathname, $callback->($status)	1190	=item aio_rmtree $pathname, $callback->($status)
1060		1191
1061	Delete a directory tree starting (and including) C<$path>, return the	1192	Delete a directory tree starting (and including) C<$path>, return the
1062	status of the final C<rmdir> only. This is a composite request that	1193	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	1194	uses C<aio_scandir> to recurse into and rmdir directories, and unlink
1064	everything else.	1195	everything else.
1065		1196
1066	=cut	1197	=cut
1067		1198
…		…
1187		1318
1188	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1319	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
1189	scalars.	1320	scalars.
1190		1321
1191	It touches (reads or writes) all memory pages in the specified	1322	It touches (reads or writes) all memory pages in the specified
1192	range inside the scalar. All caveats and parameters are the same	1323	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	1324	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	1325	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	1326	C<IO::AIO::MT_MODIFY>, which modifies the memory pages (by reading and
1196	writing an octet from it, which dirties the page).	1327	writing an octet from it, which dirties the page).
1197		1328
1198	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)	1329	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
1199		1330
1200	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1331	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
…		…
1231	documented under L<MISCELLANEOUS FUNCTIONS>.	1362	documented under L<MISCELLANEOUS FUNCTIONS>.
1232		1363
1233	Example: asynchronously lock all current and future pages into memory.	1364	Example: asynchronously lock all current and future pages into memory.
1234		1365
1235	aio_mlockall IO::AIO::MCL_FUTURE;	1366	aio_mlockall IO::AIO::MCL_FUTURE;
		1367
		1368	=item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
		1369
		1370	Queries the extents of the given file (by calling the Linux C<FIEMAP>
		1371	ioctl, see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If
		1372	the ioctl is not available on your OS, then this request will fail with
		1373	C<ENOSYS>.
		1374
		1375	C<$start> is the starting offset to query extents for, C<$length> is the
		1376	size of the range to query - if it is C<undef>, then the whole file will
		1377	be queried.
		1378
		1379	C<$flags> is a combination of flags (C<IO::AIO::FIEMAP_FLAG_SYNC> or
		1380	C<IO::AIO::FIEMAP_FLAG_XATTR> - C<IO::AIO::FIEMAP_FLAGS_COMPAT> is also
		1381	exported), and is normally C<0> or C<IO::AIO::FIEMAP_FLAG_SYNC> to query
		1382	the data portion.
		1383
		1384	C<$count> is the maximum number of extent records to return. If it is
		1385	C<undef>, then IO::AIO queries all extents of the range. As a very special
		1386	case, if it is C<0>, then the callback receives the number of extents
		1387	instead of the extents themselves (which is unreliable, see below).
		1388
		1389	If an error occurs, the callback receives no arguments. The special
		1390	C<errno> value C<IO::AIO::EBADR> is available to test for flag errors.
		1391
		1392	Otherwise, the callback receives an array reference with extent
		1393	structures. Each extent structure is an array reference itself, with the
		1394	following members:
		1395
		1396	[$logical, $physical, $length, $flags]
		1397
		1398	Flags is any combination of the following flag values (typically either C<0>
		1399	or C<IO::AIO::FIEMAP_EXTENT_LAST> (1)):
		1400
		1401	C<IO::AIO::FIEMAP_EXTENT_LAST>, C<IO::AIO::FIEMAP_EXTENT_UNKNOWN>,
		1402	C<IO::AIO::FIEMAP_EXTENT_DELALLOC>, C<IO::AIO::FIEMAP_EXTENT_ENCODED>,
		1403	C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>,
		1404	C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>,
		1405	C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or
		1406	C<IO::AIO::FIEMAP_EXTENT_SHARED>.
		1407
		1408	At the time of this writing (Linux 3.2), this requets is unreliable unless
		1409	C<$count> is C<undef>, as the kernel has all sorts of bugs preventing
		1410	it to return all extents of a range for files with large number of
		1411	extents. The code works around all these issues if C<$count> is undef.
1236		1412
1237	=item aio_group $callback->(...)	1413	=item aio_group $callback->(...)
1238		1414
1239	This is a very special aio request: Instead of doing something, it is a	1415	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	1416	container for other aio requests, which is useful if you want to bundle
…		…
1356	will still point to the original directory. Most functions accepting a	1532	will still point to the original directory. Most functions accepting a
1357	pathname will use the directory fd on newer systems, and the string on	1533	pathname will use the directory fd on newer systems, and the string on
1358	older systems. Some functions (such as realpath) will always rely on the	1534	older systems. Some functions (such as realpath) will always rely on the
1359	string form of the pathname.	1535	string form of the pathname.
1360		1536
1361	So this fucntionality is mainly useful to get some protection against	1537	So this functionality is mainly useful to get some protection against
1362	C<chdir>, to easily get an absolute path out of a relative path for future	1538	C<chdir>, to easily get an absolute path out of a relative path for future
1363	reference, and to speed up doing many operations in the same directory	1539	reference, and to speed up doing many operations in the same directory
1364	(e.g. when stat'ing all files in a directory).	1540	(e.g. when stat'ing all files in a directory).
1365		1541
1366	The following functions implement this working directory abstraction:	1542	The following functions implement this working directory abstraction:
…		…
1379	passing C<undef> as working directory component of a pathname fails the	1555	passing C<undef> as working directory component of a pathname fails the
1380	request with C<ENOENT>, there is often no need for error checking in the	1556	request with C<ENOENT>, there is often no need for error checking in the
1381	C<aio_wd> callback, as future requests using the value will fail in the	1557	C<aio_wd> callback, as future requests using the value will fail in the
1382	expected way.	1558	expected way.
1383		1559
1384	If this call isn't available because your OS lacks it or it couldn't be
1385	detected, it will be emulated by calling C<fsync> instead.
1386
1387	=item IO::AIO::CWD	1560	=item IO::AIO::CWD
1388		1561
1389	This is a compiletime constant (object) that represents the process	1562	This is a compiletime constant (object) that represents the process
1390	current working directory.	1563	current working directory.
1391		1564
1392	Specifying this object as working directory object for a pathname is as	1565	Specifying this object as working directory object for a pathname is as if
1393	if the pathname would be specified directly, without a directory object,	1566	the pathname would be specified directly, without a directory object. For
1394	e.g., these calls are functionally identical:	1567	example, these calls are functionally identical:
1395		1568
1396	aio_stat "somefile", sub { ... };	1569	aio_stat "somefile", sub { ... };
1397	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };	1570	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };
1398		1571
1399	=back	1572	=back
1400		1573
		1574	To recover the path associated with an IO::AIO::WD object, you can use
		1575	C<aio_realpath>:
		1576
		1577	aio_realpath $wd, sub {
		1578	warn "path is $_[0]\n";
		1579	};
		1580
		1581	Currently, C<aio_statvfs> always, and C<aio_rename> and C<aio_rmdir>
		1582	sometimes, fall back to using an absolue path.
1401		1583
1402	=head2 IO::AIO::REQ CLASS	1584	=head2 IO::AIO::REQ CLASS
1403		1585
1404	All non-aggregate C<aio_*> functions return an object of this class when	1586	All non-aggregate C<aio_*> functions return an object of this class when
1405	called in non-void context.	1587	called in non-void context.
…		…
1583		1765
1584	See C<poll_cb> for an example.	1766	See C<poll_cb> for an example.
1585		1767
1586	=item IO::AIO::poll_cb	1768	=item IO::AIO::poll_cb
1587		1769
1588	Process some outstanding events on the result pipe. You have to call	1770	Process some requests that have reached the result phase (i.e. they have
		1771	been executed but the results are not yet reported). You have to call
		1772	this "regularly" to finish outstanding requests.
		1773
1589	this regularly. Returns C<0> if all events could be processed (or there	1774	Returns C<0> if all events could be processed (or there were no
1590	were no events to process), or C<-1> if it returned earlier for whatever	1775	events to process), or C<-1> if it returned earlier for whatever
1591	reason. Returns immediately when no events are outstanding. The amount of	1776	reason. Returns immediately when no events are outstanding. The amount
1592	events processed depends on the settings of C<IO::AIO::max_poll_req> and	1777	of events processed depends on the settings of C<IO::AIO::max_poll_req>,
1593	C<IO::AIO::max_poll_time>.	1778	C<IO::AIO::max_poll_time> and C<IO::AIO::max_outstanding>.
1594		1779
1595	If not all requests were processed for whatever reason, the filehandle	1780	If not all requests were processed for whatever reason, the poll file
1596	will still be ready when C<poll_cb> returns, so normally you don't have to	1781	descriptor will still be ready when C<poll_cb> returns, so normally you
1597	do anything special to have it called later.	1782	don't have to do anything special to have it called later.
1598		1783
1599	Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes	1784	Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes
1600	ready, it can be beneficial to call this function from loops which submit	1785	ready, it can be beneficial to call this function from loops which submit
1601	a lot of requests, to make sure the results get processed when they become	1786	a lot of requests, to make sure the results get processed when they become
1602	available and not just when the loop is finished and the event loop takes	1787	available and not just when the loop is finished and the event loop takes
…		…
1611	poll => 'r', async => 1,	1796	poll => 'r', async => 1,
1612	cb => \&IO::AIO::poll_cb);	1797	cb => \&IO::AIO::poll_cb);
1613		1798
1614	=item IO::AIO::poll_wait	1799	=item IO::AIO::poll_wait
1615		1800
1616	If there are any outstanding requests and none of them in the result	1801	Wait until either at least one request is in the result phase or no
1617	phase, wait till the result filehandle becomes ready for reading (simply	1802	requests are outstanding anymore.
1618	does a C<select> on the filehandle. This is useful if you want to	1803
1619	synchronously wait for some requests to finish).	1804	This is useful if you want to synchronously wait for some requests to
		1805	become ready, without actually handling them.
1620		1806
1621	See C<nreqs> for an example.	1807	See C<nreqs> for an example.
1622		1808
1623	=item IO::AIO::poll	1809	=item IO::AIO::poll
1624		1810
…		…
1745		1931
1746	This is a very bad function to use in interactive programs because it	1932	This is a very bad function to use in interactive programs because it
1747	blocks, and a bad way to reduce concurrency because it is inexact: Better	1933	blocks, and a bad way to reduce concurrency because it is inexact: Better
1748	use an C<aio_group> together with a feed callback.	1934	use an C<aio_group> together with a feed callback.
1749		1935
1750	It's main use is in scripts without an event loop - when you want to stat	1936	Its main use is in scripts without an event loop - when you want to stat
1751	a lot of files, you can write somehting like this:	1937	a lot of files, you can write somehting like this:
1752		1938
1753	IO::AIO::max_outstanding 32;	1939	IO::AIO::max_outstanding 32;
1754		1940
1755	for my $path (...) {	1941	for my $path (...) {
…		…
1795		1981
1796	=back	1982	=back
1797		1983
1798	=head3 MISCELLANEOUS FUNCTIONS	1984	=head3 MISCELLANEOUS FUNCTIONS
1799		1985
1800	IO::AIO implements some functions that might be useful, but are not	1986	IO::AIO implements some functions that are useful when you want to use
1801	asynchronous.	1987	some "Advanced I/O" function not available to in Perl, without going the
		1988	"Asynchronous I/O" route. Many of these have an asynchronous C<aio_*>
		1989	counterpart.
1802		1990
1803	=over 4	1991	=over 4
1804		1992
1805	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count	1993	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
1806		1994
…		…
1843	ENOSYS, otherwise the return value of C<mprotect>.	2031	ENOSYS, otherwise the return value of C<mprotect>.
1844		2032
1845	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]	2033	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]
1846		2034
1847	Memory-maps a file (or anonymous memory range) and attaches it to the	2035	Memory-maps a file (or anonymous memory range) and attaches it to the
1848	given C<$scalar>, which will act like a string scalar.	2036	given C<$scalar>, which will act like a string scalar. Returns true on
		2037	success, and false otherwise.
1849		2038
1850	The only operations allowed on the scalar are C<substr>/C<vec> that don't	2039	The only operations allowed on the scalar are C<substr>/C<vec> that don't
1851	change the string length, and most read-only operations such as copying it	2040	change the string length, and most read-only operations such as copying it
1852	or searching it with regexes and so on.	2041	or searching it with regexes and so on.
1853		2042
…		…
1906	Calls the C<munlockall> function.	2095	Calls the C<munlockall> function.
1907		2096
1908	On systems that do not implement C<munlockall>, this function returns	2097	On systems that do not implement C<munlockall>, this function returns
1909	ENOSYS, otherwise the return value of C<munlockall>.	2098	ENOSYS, otherwise the return value of C<munlockall>.
1910		2099
		2100	=item IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags
		2101
		2102	Calls the GNU/Linux C<splice(2)> syscall, if available. If C<$r_off> or
		2103	C<$w_off> are C<undef>, then C<NULL> is passed for these, otherwise they
		2104	should be the file offset.
		2105
		2106	C<$r_fh> and C<$w_fh> should not refer to the same file, as splice might
		2107	silently corrupt the data in this case.
		2108
		2109	The following symbol flag values are available: C<IO::AIO::SPLICE_F_MOVE>,
		2110	C<IO::AIO::SPLICE_F_NONBLOCK>, C<IO::AIO::SPLICE_F_MORE> and
		2111	C<IO::AIO::SPLICE_F_GIFT>.
		2112
		2113	See the C<splice(2)> manpage for details.
		2114
		2115	=item IO::AIO::tee $r_fh, $w_fh, $length, $flags
		2116
		2117	Calls the GNU/Linux C<tee(2)> syscall, see its manpage and the
		2118	description for C<IO::AIO::splice> above for details.
		2119
		2120	=item $actual_size = IO::AIO::pipesize $r_fh[, $new_size]
		2121
		2122	Attempts to query or change the pipe buffer size. Obviously works only
		2123	on pipes, and currently works only on GNU/Linux systems, and fails with
		2124	C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer
		2125	size on other systems, drop me a note.
		2126
1911	=back	2127	=back
1912		2128
1913	=cut	2129	=cut
1914		2130
1915	min_parallel 8;	2131	min_parallel 8;

Diff Legend

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

Comparing IO-AIO/AIO.pm (file contents): Revision 1.217 by root, Sun Oct 9 22:25:00 2011 UTC vs. Revision 1.248 by root, Sun Jul 27 22:10:53 2014 UTC

Diff Legend

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.217 by root, Sun Oct 9 22:25:00 2011 UTC vs.
Revision 1.248 by root, Sun Jul 27 22:10:53 2014 UTC