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

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.229 by root, Wed Jul 25 16:32:30 2012 UTC vs.
Revision 1.263 by root, Tue Jul 12 20:46:33 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 = '4.15';	172	our $VERSION = 4.34;
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_fcntl aio_ioctl
178	aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range aio_fallocate	177	aio_sync aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range
179	aio_pathsync aio_readahead aio_fiemap	178	aio_pathsync aio_readahead aio_fiemap aio_allocate
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)
…		…
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)
226	aio_allocate $fh, $mode, $offset, $len, $callback->($status)	225	aio_allocate $fh, $mode, $offset, $len, $callback->($status)
		226	aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
227	aio_unlink $pathname, $callback->($status)	227	aio_unlink $pathname, $callback->($status)
228	aio_mknod $pathname, $mode, $dev, $callback->($status)	228	aio_mknod $pathname, $mode, $dev, $callback->($status)
229	aio_link $srcpath, $dstpath, $callback->($status)	229	aio_link $srcpath, $dstpath, $callback->($status)
230	aio_symlink $srcpath, $dstpath, $callback->($status)	230	aio_symlink $srcpath, $dstpath, $callback->($status)
231	aio_readlink $pathname, $callback->($link)	231	aio_readlink $pathname, $callback->($link)
232	aio_realpath $pathname, $callback->($link)	232	aio_realpath $pathname, $callback->($path)
233	aio_rename $srcpath, $dstpath, $callback->($status)	233	aio_rename $srcpath, $dstpath, $callback->($status)
234	aio_mkdir $pathname, $mode, $callback->($status)	234	aio_mkdir $pathname, $mode, $callback->($status)
235	aio_rmdir $pathname, $callback->($status)	235	aio_rmdir $pathname, $callback->($status)
236	aio_readdir $pathname, $callback->($entries)	236	aio_readdir $pathname, $callback->($entries)
237	aio_readdirx $pathname, $flags, $callback->($entries, $flags)	237	aio_readdirx $pathname, $flags, $callback->($entries, $flags)
…		…
240	aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)	240	aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
241	aio_load $pathname, $data, $callback->($status)	241	aio_load $pathname, $data, $callback->($status)
242	aio_copy $srcpath, $dstpath, $callback->($status)	242	aio_copy $srcpath, $dstpath, $callback->($status)
243	aio_move $srcpath, $dstpath, $callback->($status)	243	aio_move $srcpath, $dstpath, $callback->($status)
244	aio_rmtree $pathname, $callback->($status)	244	aio_rmtree $pathname, $callback->($status)
		245	aio_fcntl $fh, $cmd, $arg, $callback->($status)
		246	aio_ioctl $fh, $request, $buf, $callback->($status)
245	aio_sync $callback->($status)	247	aio_sync $callback->($status)
246	aio_syncfs $fh, $callback->($status)	248	aio_syncfs $fh, $callback->($status)
247	aio_fsync $fh, $callback->($status)	249	aio_fsync $fh, $callback->($status)
248	aio_fdatasync $fh, $callback->($status)	250	aio_fdatasync $fh, $callback->($status)
249	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)	251	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
…		…
361		363
362		364
363	=item aio_open $pathname, $flags, $mode, $callback->($fh)	365	=item aio_open $pathname, $flags, $mode, $callback->($fh)
364		366
365	Asynchronously open or create a file and call the callback with a newly	367	Asynchronously open or create a file and call the callback with a newly
366	created filehandle for the file.	368	created filehandle for the file (or C<undef> in case of an error).
367		369
368	The pathname passed to C<aio_open> must be absolute. See API NOTES, above,	370	The pathname passed to C<aio_open> must be absolute. See API NOTES, above,
369	for an explanation.	371	for an explanation.
370		372
371	The C<$flags> argument is a bitmask. See the C<Fcntl> module for a	373	The C<$flags> argument is a bitmask. See the C<Fcntl> module for a
…		…
394	following POSIX and non-POSIX constants are available (missing ones on	396	following POSIX and non-POSIX constants are available (missing ones on
395	your system are, as usual, C<0>):	397	your system are, as usual, C<0>):
396		398
397	C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,	399	C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,
398	C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>,	400	C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>,
399	C<O_RSYNC>, C<O_SYNC> and C<O_TTY_INIT>.	401	C<O_RSYNC>, C<O_SYNC>, C<O_PATH>, C<O_TMPFILE>, and C<O_TTY_INIT>.
400		402
401		403
402	=item aio_close $fh, $callback->($status)	404	=item aio_close $fh, $callback->($status)
403		405
404	Asynchronously close a file and call the callback with the result	406	Asynchronously close a file and call the callback with the result
…		…
508	As native sendfile syscalls (as practically any non-POSIX interface hacked	510	As native sendfile syscalls (as practically any non-POSIX interface hacked
509	together in a hurry to improve benchmark numbers) tend to be rather buggy	511	together in a hurry to improve benchmark numbers) tend to be rather buggy
510	on many systems, this implementation tries to work around some known bugs	512	on many systems, this implementation tries to work around some known bugs
511	in Linux and FreeBSD kernels (probably others, too), but that might fail,	513	in Linux and FreeBSD kernels (probably others, too), but that might fail,
512	so you really really should check the return value of C<aio_sendfile> -	514	so you really really should check the return value of C<aio_sendfile> -
513	fewre bytes than expected might have been transferred.	515	fewer bytes than expected might have been transferred.
514		516
515		517
516	=item aio_readahead $fh,$offset,$length, $callback->($retval)	518	=item aio_readahead $fh,$offset,$length, $callback->($retval)
517		519
518	C<aio_readahead> populates the page cache with data from a file so that	520	C<aio_readahead> populates the page cache with data from a file so that
…		…
522	whole pages, so that offset is effectively rounded down to a page boundary	524	whole pages, so that offset is effectively rounded down to a page boundary
523	and bytes are read up to the next page boundary greater than or equal to	525	and bytes are read up to the next page boundary greater than or equal to
524	(off-set+length). C<aio_readahead> does not read beyond the end of the	526	(off-set+length). C<aio_readahead> does not read beyond the end of the
525	file. The current file offset of the file is left unchanged.	527	file. The current file offset of the file is left unchanged.
526		528
527	If that syscall doesn't exist (likely if your OS isn't Linux) it will be	529	If that syscall doesn't exist (likely if your kernel isn't Linux) it will
528	emulated by simply reading the data, which would have a similar effect.	530	be emulated by simply reading the data, which would have a similar effect.
529		531
530		532
531	=item aio_stat $fh_or_path, $callback->($status)	533	=item aio_stat $fh_or_path, $callback->($status)
532		534
533	=item aio_lstat $fh, $callback->($status)	535	=item aio_lstat $fh, $callback->($status)
…		…
602	namemax => 255,	604	namemax => 255,
603	frsize => 1024,	605	frsize => 1024,
604	fsid => 1810	606	fsid => 1810
605	}	607	}
606		608
		609	Here is a (likely partial - send me updates!) list of fsid values used by
		610	Linux - it is safe to hardcode these when C<$^O> is C<linux>:
		611
		612	0x0000adf5 adfs
		613	0x0000adff affs
		614	0x5346414f afs
		615	0x09041934 anon-inode filesystem
		616	0x00000187 autofs
		617	0x42465331 befs
		618	0x1badface bfs
		619	0x42494e4d binfmt_misc
		620	0x9123683e btrfs
		621	0x0027e0eb cgroupfs
		622	0xff534d42 cifs
		623	0x73757245 coda
		624	0x012ff7b7 coh
		625	0x28cd3d45 cramfs
		626	0x453dcd28 cramfs-wend (wrong endianness)
		627	0x64626720 debugfs
		628	0x00001373 devfs
		629	0x00001cd1 devpts
		630	0x0000f15f ecryptfs
		631	0x00414a53 efs
		632	0x0000137d ext
		633	0x0000ef53 ext2/ext3/ext4
		634	0x0000ef51 ext2
		635	0xf2f52010 f2fs
		636	0x00004006 fat
		637	0x65735546 fuseblk
		638	0x65735543 fusectl
		639	0x0bad1dea futexfs
		640	0x01161970 gfs2
		641	0x47504653 gpfs
		642	0x00004244 hfs
		643	0xf995e849 hpfs
		644	0x00c0ffee hostfs
		645	0x958458f6 hugetlbfs
		646	0x2bad1dea inotifyfs
		647	0x00009660 isofs
		648	0x000072b6 jffs2
		649	0x3153464a jfs
		650	0x6b414653 k-afs
		651	0x0bd00bd0 lustre
		652	0x0000137f minix
		653	0x0000138f minix 30 char names
		654	0x00002468 minix v2
		655	0x00002478 minix v2 30 char names
		656	0x00004d5a minix v3
		657	0x19800202 mqueue
		658	0x00004d44 msdos
		659	0x0000564c novell
		660	0x00006969 nfs
		661	0x6e667364 nfsd
		662	0x00003434 nilfs
		663	0x5346544e ntfs
		664	0x00009fa1 openprom
		665	0x7461636F ocfs2
		666	0x00009fa0 proc
		667	0x6165676c pstorefs
		668	0x0000002f qnx4
		669	0x68191122 qnx6
		670	0x858458f6 ramfs
		671	0x52654973 reiserfs
		672	0x00007275 romfs
		673	0x67596969 rpc_pipefs
		674	0x73636673 securityfs
		675	0xf97cff8c selinux
		676	0x0000517b smb
		677	0x534f434b sockfs
		678	0x73717368 squashfs
		679	0x62656572 sysfs
		680	0x012ff7b6 sysv2
		681	0x012ff7b5 sysv4
		682	0x01021994 tmpfs
		683	0x15013346 udf
		684	0x00011954 ufs
		685	0x54190100 ufs byteswapped
		686	0x00009fa2 usbdevfs
		687	0x01021997 v9fs
		688	0xa501fcf5 vxfs
		689	0xabba1974 xenfs
		690	0x012ff7b4 xenix
		691	0x58465342 xfs
		692	0x012fd16d xia
607		693
608	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	694	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
609		695
610	Works like perl's C<utime> function (including the special case of $atime	696	Works like perl's C<utime> function (including the special case of $atime
611	and $mtime being undef). Fractional times are supported if the underlying	697	and $mtime being undef). Fractional times are supported if the underlying
…		…
641	Works like truncate(2) or ftruncate(2).	727	Works like truncate(2) or ftruncate(2).
642		728
643		729
644	=item aio_allocate $fh, $mode, $offset, $len, $callback->($status)	730	=item aio_allocate $fh, $mode, $offset, $len, $callback->($status)
645		731
646	Allocates or freed disk space according to the C<$mode> argument. See the	732	Allocates or frees disk space according to the C<$mode> argument. See the
647	linux C<fallocate> docuemntation for details.	733	linux C<fallocate> documentation for details.
648		734
649	C<$mode> can currently be C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE>	735	C<$mode> is usually C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> to allocate
650	to allocate space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE \|	736	space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE \| IO::AIO::FALLOC_FL_KEEP_SIZE>,
651	IO::AIO::FALLOC_FL_KEEP_SIZE>, to deallocate a file range.	737	to deallocate a file range.
		738
		739	IO::AIO also supports C<FALLOC_FL_COLLAPSE_RANGE>, to remove a range
		740	(without leaving a hole) and C<FALLOC_FL_ZERO_RANGE>, to zero a range (see
		741	your L<fallocate(2)> manpage).
652		742
653	The file system block size used by C<fallocate> is presumably the	743	The file system block size used by C<fallocate> is presumably the
654	C<f_bsize> returned by C<statvfs>.	744	C<f_bsize> returned by C<statvfs>.
655		745
656	If C<fallocate> isn't available or cannot be emulated (currently no	746	If C<fallocate> isn't available or cannot be emulated (currently no
…		…
701		791
702		792
703	=item aio_realpath $pathname, $callback->($path)	793	=item aio_realpath $pathname, $callback->($path)
704		794
705	Asynchronously make the path absolute and resolve any symlinks in	795	Asynchronously make the path absolute and resolve any symlinks in
706	C<$path>. The resulting path only consists of directories (Same as	796	C<$path>. The resulting path only consists of directories (same as
707	L<Cwd::realpath>).	797	L<Cwd::realpath>).
708		798
709	This request can be used to get the absolute path of the current working	799	This request can be used to get the absolute path of the current working
710	directory by passing it a path of F<.> (a single dot).	800	directory by passing it a path of F<.> (a single dot).
711		801
712		802
713	=item aio_rename $srcpath, $dstpath, $callback->($status)	803	=item aio_rename $srcpath, $dstpath, $callback->($status)
714		804
715	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as	805	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as
716	rename(2) and call the callback with the result code.	806	rename(2) and call the callback with the result code.
		807
		808	On systems that support the AIO::WD working directory abstraction
		809	natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead
		810	of failing, C<rename> is called on the absolute path of C<$wd>.
717		811
718		812
719	=item aio_mkdir $pathname, $mode, $callback->($status)	813	=item aio_mkdir $pathname, $mode, $callback->($status)
720		814
721	Asynchronously mkdir (create) a directory and call the callback with	815	Asynchronously mkdir (create) a directory and call the callback with
…		…
725		819
726	=item aio_rmdir $pathname, $callback->($status)	820	=item aio_rmdir $pathname, $callback->($status)
727		821
728	Asynchronously rmdir (delete) a directory and call the callback with the	822	Asynchronously rmdir (delete) a directory and call the callback with the
729	result code.	823	result code.
		824
		825	On systems that support the AIO::WD working directory abstraction
		826	natively, the case C<[$wd, "."]> is specialcased - instead of failing,
		827	C<rmdir> is called on the absolute path of C<$wd>.
730		828
731		829
732	=item aio_readdir $pathname, $callback->($entries)	830	=item aio_readdir $pathname, $callback->($entries)
733		831
734	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire	832	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire
…		…
1099	}	1197	}
1100		1198
1101	=item aio_rmtree $pathname, $callback->($status)	1199	=item aio_rmtree $pathname, $callback->($status)
1102		1200
1103	Delete a directory tree starting (and including) C<$path>, return the	1201	Delete a directory tree starting (and including) C<$path>, return the
1104	status of the final C<rmdir> only. This is a composite request that	1202	status of the final C<rmdir> only. This is a composite request that
1105	uses C<aio_scandir> to recurse into and rmdir directories, and unlink	1203	uses C<aio_scandir> to recurse into and rmdir directories, and unlink
1106	everything else.	1204	everything else.
1107		1205
1108	=cut	1206	=cut
1109		1207
…		…
1130	add $grp $dirgrp;	1228	add $grp $dirgrp;
1131	};	1229	};
1132		1230
1133	$grp	1231	$grp
1134	}	1232	}
		1233
		1234	=item aio_fcntl $fh, $cmd, $arg, $callback->($status)
		1235
		1236	=item aio_ioctl $fh, $request, $buf, $callback->($status)
		1237
		1238	These work just like the C<fcntl> and C<ioctl> built-in functions, except
		1239	they execute asynchronously and pass the return value to the callback.
		1240
		1241	Both calls can be used for a lot of things, some of which make more sense
		1242	to run asynchronously in their own thread, while some others make less
		1243	sense. For example, calls that block waiting for external events, such
		1244	as locking, will also lock down an I/O thread while it is waiting, which
		1245	can deadlock the whole I/O system. At the same time, there might be no
		1246	alternative to using a thread to wait.
		1247
		1248	So in general, you should only use these calls for things that do
		1249	(filesystem) I/O, not for things that wait for other events (network,
		1250	other processes), although if you are careful and know what you are doing,
		1251	you still can.
1135		1252
1136	=item aio_sync $callback->($status)	1253	=item aio_sync $callback->($status)
1137		1254
1138	Asynchronously call sync and call the callback when finished.	1255	Asynchronously call sync and call the callback when finished.
1139		1256
…		…
1229		1346
1230	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1347	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
1231	scalars.	1348	scalars.
1232		1349
1233	It touches (reads or writes) all memory pages in the specified	1350	It touches (reads or writes) all memory pages in the specified
1234	range inside the scalar. All caveats and parameters are the same	1351	range inside the scalar. All caveats and parameters are the same
1235	as for C<aio_msync>, above, except for flags, which must be either	1352	as for C<aio_msync>, above, except for flags, which must be either
1236	C<0> (which reads all pages and ensures they are instantiated) or	1353	C<0> (which reads all pages and ensures they are instantiated) or
1237	C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and	1354	C<IO::AIO::MT_MODIFY>, which modifies the memory pages (by reading and
1238	writing an octet from it, which dirties the page).	1355	writing an octet from it, which dirties the page).
1239		1356
1240	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)	1357	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
1241		1358
1242	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1359	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
…		…
1276		1393
1277	aio_mlockall IO::AIO::MCL_FUTURE;	1394	aio_mlockall IO::AIO::MCL_FUTURE;
1278		1395
1279	=item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)	1396	=item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
1280		1397
1281	Queries the extents of the given file (by calling the Linux FIEMAP ioctl,	1398	Queries the extents of the given file (by calling the Linux C<FIEMAP>
1282	see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If the	1399	ioctl, see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If
1283	C<ioctl> is not available on your OS, then this rquiest will fail with	1400	the ioctl is not available on your OS, then this request will fail with
1284	C<ENOSYS>.	1401	C<ENOSYS>.
1285		1402
1286	C<$start> is the starting offset to query extents for, C<$length> is the	1403	C<$start> is the starting offset to query extents for, C<$length> is the
1287	size of the range to query - if it is C<undef>, then the whole file will	1404	size of the range to query - if it is C<undef>, then the whole file will
1288	be queried.	1405	be queried.
…		…
1291	C<IO::AIO::FIEMAP_FLAG_XATTR> - C<IO::AIO::FIEMAP_FLAGS_COMPAT> is also	1408	C<IO::AIO::FIEMAP_FLAG_XATTR> - C<IO::AIO::FIEMAP_FLAGS_COMPAT> is also
1292	exported), and is normally C<0> or C<IO::AIO::FIEMAP_FLAG_SYNC> to query	1409	exported), and is normally C<0> or C<IO::AIO::FIEMAP_FLAG_SYNC> to query
1293	the data portion.	1410	the data portion.
1294		1411
1295	C<$count> is the maximum number of extent records to return. If it is	1412	C<$count> is the maximum number of extent records to return. If it is
1296	C<undef>, then IO::AIO queries all extents of the file. As a very special	1413	C<undef>, then IO::AIO queries all extents of the range. As a very special
1297	case, if it is C<0>, then the callback receives the number of extents	1414	case, if it is C<0>, then the callback receives the number of extents
1298	instead of the extents themselves.	1415	instead of the extents themselves (which is unreliable, see below).
1299		1416
1300	If an error occurs, the callback receives no arguments. The special	1417	If an error occurs, the callback receives no arguments. The special
1301	C<errno> value C<IO::AIO::EBADR> is available to test for flag errors.	1418	C<errno> value C<IO::AIO::EBADR> is available to test for flag errors.
1302		1419
1303	Otherwise, the callback receives an array reference with extent	1420	Otherwise, the callback receives an array reference with extent
…		…
1305	following members:	1422	following members:
1306		1423
1307	[$logical, $physical, $length, $flags]	1424	[$logical, $physical, $length, $flags]
1308		1425
1309	Flags is any combination of the following flag values (typically either C<0>	1426	Flags is any combination of the following flag values (typically either C<0>
1310	or C<IO::AIO::FIEMAP_EXTENT_LAST>):	1427	or C<IO::AIO::FIEMAP_EXTENT_LAST> (1)):
1311		1428
1312	C<IO::AIO::FIEMAP_EXTENT_LAST>, C<IO::AIO::FIEMAP_EXTENT_UNKNOWN>,	1429	C<IO::AIO::FIEMAP_EXTENT_LAST>, C<IO::AIO::FIEMAP_EXTENT_UNKNOWN>,
1313	C<IO::AIO::FIEMAP_EXTENT_DELALLOC>, C<IO::AIO::FIEMAP_EXTENT_ENCODED>,	1430	C<IO::AIO::FIEMAP_EXTENT_DELALLOC>, C<IO::AIO::FIEMAP_EXTENT_ENCODED>,
1314	C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>,	1431	C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>,
1315	C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>,	1432	C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>,
1316	C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or	1433	C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or
1317	C<IO::AIO::FIEMAP_EXTENT_SHARED>.	1434	C<IO::AIO::FIEMAP_EXTENT_SHARED>.
1318		1435
		1436	At the time of this writing (Linux 3.2), this requets is unreliable unless
		1437	C<$count> is C<undef>, as the kernel has all sorts of bugs preventing
		1438	it to return all extents of a range for files with large number of
		1439	extents. The code works around all these issues if C<$count> is undef.
		1440
1319	=item aio_group $callback->(...)	1441	=item aio_group $callback->(...)
1320		1442
1321	This is a very special aio request: Instead of doing something, it is a	1443	This is a very special aio request: Instead of doing something, it is a
1322	container for other aio requests, which is useful if you want to bundle	1444	container for other aio requests, which is useful if you want to bundle
1323	many requests into a single, composite, request with a definite callback	1445	many requests into a single, composite, request with a definite callback
…		…
1406	aio_stat [$etcdir, "passwd"], sub {	1528	aio_stat [$etcdir, "passwd"], sub {
1407	# yay	1529	# yay
1408	};	1530	};
1409	};	1531	};
1410		1532
1411	That C<aio_wd> is a request and not a normal function shows that creating	1533	The fact that C<aio_wd> is a request and not a normal function shows that
1412	an IO::AIO::WD object is itself a potentially blocking operation, which is	1534	creating an IO::AIO::WD object is itself a potentially blocking operation,
1413	why it is done asynchronously.	1535	which is why it is done asynchronously.
1414		1536
1415	To stat the directory obtained with C<aio_wd> above, one could write	1537	To stat the directory obtained with C<aio_wd> above, one could write
1416	either of the following three request calls:	1538	either of the following three request calls:
1417		1539
1418	aio_lstat "/etc" , sub { ... # pathname as normal string	1540	aio_lstat "/etc" , sub { ... # pathname as normal string
…		…
1438	will still point to the original directory. Most functions accepting a	1560	will still point to the original directory. Most functions accepting a
1439	pathname will use the directory fd on newer systems, and the string on	1561	pathname will use the directory fd on newer systems, and the string on
1440	older systems. Some functions (such as realpath) will always rely on the	1562	older systems. Some functions (such as realpath) will always rely on the
1441	string form of the pathname.	1563	string form of the pathname.
1442		1564
1443	So this fucntionality is mainly useful to get some protection against	1565	So this functionality is mainly useful to get some protection against
1444	C<chdir>, to easily get an absolute path out of a relative path for future	1566	C<chdir>, to easily get an absolute path out of a relative path for future
1445	reference, and to speed up doing many operations in the same directory	1567	reference, and to speed up doing many operations in the same directory
1446	(e.g. when stat'ing all files in a directory).	1568	(e.g. when stat'ing all files in a directory).
1447		1569
1448	The following functions implement this working directory abstraction:	1570	The following functions implement this working directory abstraction:
…		…
1461	passing C<undef> as working directory component of a pathname fails the	1583	passing C<undef> as working directory component of a pathname fails the
1462	request with C<ENOENT>, there is often no need for error checking in the	1584	request with C<ENOENT>, there is often no need for error checking in the
1463	C<aio_wd> callback, as future requests using the value will fail in the	1585	C<aio_wd> callback, as future requests using the value will fail in the
1464	expected way.	1586	expected way.
1465		1587
1466	If this call isn't available because your OS lacks it or it couldn't be
1467	detected, it will be emulated by calling C<fsync> instead.
1468
1469	=item IO::AIO::CWD	1588	=item IO::AIO::CWD
1470		1589
1471	This is a compiletime constant (object) that represents the process	1590	This is a compiletime constant (object) that represents the process
1472	current working directory.	1591	current working directory.
1473		1592
1474	Specifying this object as working directory object for a pathname is as	1593	Specifying this object as working directory object for a pathname is as if
1475	if the pathname would be specified directly, without a directory object,	1594	the pathname would be specified directly, without a directory object. For
1476	e.g., these calls are functionally identical:	1595	example, these calls are functionally identical:
1477		1596
1478	aio_stat "somefile", sub { ... };	1597	aio_stat "somefile", sub { ... };
1479	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };	1598	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };
1480		1599
1481	=back	1600	=back
1482		1601
		1602	To recover the path associated with an IO::AIO::WD object, you can use
		1603	C<aio_realpath>:
		1604
		1605	aio_realpath $wd, sub {
		1606	warn "path is $_[0]\n";
		1607	};
		1608
		1609	Currently, C<aio_statvfs> always, and C<aio_rename> and C<aio_rmdir>
		1610	sometimes, fall back to using an absolue path.
1483		1611
1484	=head2 IO::AIO::REQ CLASS	1612	=head2 IO::AIO::REQ CLASS
1485		1613
1486	All non-aggregate C<aio_*> functions return an object of this class when	1614	All non-aggregate C<aio_*> functions return an object of this class when
1487	called in non-void context.	1615	called in non-void context.
…		…
1665		1793
1666	See C<poll_cb> for an example.	1794	See C<poll_cb> for an example.
1667		1795
1668	=item IO::AIO::poll_cb	1796	=item IO::AIO::poll_cb
1669		1797
1670	Process some outstanding events on the result pipe. You have to call	1798	Process some requests that have reached the result phase (i.e. they have
		1799	been executed but the results are not yet reported). You have to call
		1800	this "regularly" to finish outstanding requests.
		1801
1671	this regularly. Returns C<0> if all events could be processed (or there	1802	Returns C<0> if all events could be processed (or there were no
1672	were no events to process), or C<-1> if it returned earlier for whatever	1803	events to process), or C<-1> if it returned earlier for whatever
1673	reason. Returns immediately when no events are outstanding. The amount of	1804	reason. Returns immediately when no events are outstanding. The amount
1674	events processed depends on the settings of C<IO::AIO::max_poll_req> and	1805	of events processed depends on the settings of C<IO::AIO::max_poll_req>,
1675	C<IO::AIO::max_poll_time>.	1806	C<IO::AIO::max_poll_time> and C<IO::AIO::max_outstanding>.
1676		1807
1677	If not all requests were processed for whatever reason, the filehandle	1808	If not all requests were processed for whatever reason, the poll file
1678	will still be ready when C<poll_cb> returns, so normally you don't have to	1809	descriptor will still be ready when C<poll_cb> returns, so normally you
1679	do anything special to have it called later.	1810	don't have to do anything special to have it called later.
1680		1811
1681	Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes	1812	Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes
1682	ready, it can be beneficial to call this function from loops which submit	1813	ready, it can be beneficial to call this function from loops which submit
1683	a lot of requests, to make sure the results get processed when they become	1814	a lot of requests, to make sure the results get processed when they become
1684	available and not just when the loop is finished and the event loop takes	1815	available and not just when the loop is finished and the event loop takes
…		…
1693	poll => 'r', async => 1,	1824	poll => 'r', async => 1,
1694	cb => \&IO::AIO::poll_cb);	1825	cb => \&IO::AIO::poll_cb);
1695		1826
1696	=item IO::AIO::poll_wait	1827	=item IO::AIO::poll_wait
1697		1828
1698	If there are any outstanding requests and none of them in the result	1829	Wait until either at least one request is in the result phase or no
1699	phase, wait till the result filehandle becomes ready for reading (simply	1830	requests are outstanding anymore.
1700	does a C<select> on the filehandle. This is useful if you want to	1831
1701	synchronously wait for some requests to finish).	1832	This is useful if you want to synchronously wait for some requests to
		1833	become ready, without actually handling them.
1702		1834
1703	See C<nreqs> for an example.	1835	See C<nreqs> for an example.
1704		1836
1705	=item IO::AIO::poll	1837	=item IO::AIO::poll
1706		1838
…		…
1827		1959
1828	This is a very bad function to use in interactive programs because it	1960	This is a very bad function to use in interactive programs because it
1829	blocks, and a bad way to reduce concurrency because it is inexact: Better	1961	blocks, and a bad way to reduce concurrency because it is inexact: Better
1830	use an C<aio_group> together with a feed callback.	1962	use an C<aio_group> together with a feed callback.
1831		1963
1832	It's main use is in scripts without an event loop - when you want to stat	1964	Its main use is in scripts without an event loop - when you want to stat
1833	a lot of files, you can write somehting like this:	1965	a lot of files, you can write somehting like this:
1834		1966
1835	IO::AIO::max_outstanding 32;	1967	IO::AIO::max_outstanding 32;
1836		1968
1837	for my $path (...) {	1969	for my $path (...) {
…		…
1877		2009
1878	=back	2010	=back
1879		2011
1880	=head3 MISCELLANEOUS FUNCTIONS	2012	=head3 MISCELLANEOUS FUNCTIONS
1881		2013
1882	IO::AIO implements some functions that might be useful, but are not	2014	IO::AIO implements some functions that are useful when you want to use
1883	asynchronous.	2015	some "Advanced I/O" function not available to in Perl, without going the
		2016	"Asynchronous I/O" route. Many of these have an asynchronous C<aio_*>
		2017	counterpart.
1884		2018
1885	=over 4	2019	=over 4
1886		2020
1887	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count	2021	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
1888		2022
…		…
1907	=item IO::AIO::madvise $scalar, $offset, $len, $advice	2041	=item IO::AIO::madvise $scalar, $offset, $len, $advice
1908		2042
1909	Simply calls the C<posix_madvise> function (see its	2043	Simply calls the C<posix_madvise> function (see its
1910	manpage for details). The following advice constants are	2044	manpage for details). The following advice constants are
1911	available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,	2045	available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,
1912	C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>.	2046	C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>,
		2047	C<IO::AIO::MADV_FREE>.
1913		2048
1914	On systems that do not implement C<posix_madvise>, this function returns	2049	On systems that do not implement C<posix_madvise>, this function returns
1915	ENOSYS, otherwise the return value of C<posix_madvise>.	2050	ENOSYS, otherwise the return value of C<posix_madvise>.
1916		2051
1917	=item IO::AIO::mprotect $scalar, $offset, $len, $protect	2052	=item IO::AIO::mprotect $scalar, $offset, $len, $protect
…		…
1947	filesize.	2082	filesize.
1948		2083
1949	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,	2084	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,
1950	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,	2085	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,
1951		2086
1952	C<$flags> can be a combination of C<IO::AIO::MAP_SHARED> or	2087	C<$flags> can be a combination of
1953	C<IO::AIO::MAP_PRIVATE>, or a number of system-specific flags (when	2088	C<IO::AIO::MAP_SHARED> or
1954	not available, the are defined as 0): C<IO::AIO::MAP_ANONYMOUS>	2089	C<IO::AIO::MAP_PRIVATE>,
		2090	or a number of system-specific flags (when not available, the are C<0>):
1955	(which is set to C<MAP_ANON> if your system only provides this	2091	C<IO::AIO::MAP_ANONYMOUS> (which is set to C<MAP_ANON> if your system only provides this constant),
1956	constant), C<IO::AIO::MAP_HUGETLB>, C<IO::AIO::MAP_LOCKED>,	2092	C<IO::AIO::MAP_LOCKED>,
1957	C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or	2093	C<IO::AIO::MAP_NORESERVE>,
		2094	C<IO::AIO::MAP_POPULATE>,
1958	C<IO::AIO::MAP_NONBLOCK>	2095	C<IO::AIO::MAP_NONBLOCK>,
		2096	C<IO::AIO::MAP_FIXED>,
		2097	C<IO::AIO::MAP_GROWSDOWN>,
		2098	C<IO::AIO::MAP_32BIT>,
		2099	C<IO::AIO::MAP_HUGETLB> or
		2100	C<IO::AIO::MAP_STACK>.
1959		2101
1960	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.	2102	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.
1961		2103
1962	C<$offset> is the offset from the start of the file - it generally must be	2104	C<$offset> is the offset from the start of the file - it generally must be
1963	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.	2105	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.
…		…
2006		2148
2007	See the C<splice(2)> manpage for details.	2149	See the C<splice(2)> manpage for details.
2008		2150
2009	=item IO::AIO::tee $r_fh, $w_fh, $length, $flags	2151	=item IO::AIO::tee $r_fh, $w_fh, $length, $flags
2010		2152
2011	Calls the GNU/Linux C<tee(2)> syscall, see it's manpage and the	2153	Calls the GNU/Linux C<tee(2)> syscall, see its manpage and the
2012	description for C<IO::AIO::splice> above for details.	2154	description for C<IO::AIO::splice> above for details.
		2155
		2156	=item $actual_size = IO::AIO::pipesize $r_fh[, $new_size]
		2157
		2158	Attempts to query or change the pipe buffer size. Obviously works only
		2159	on pipes, and currently works only on GNU/Linux systems, and fails with
		2160	C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer
		2161	size on other systems, drop me a note.
		2162
		2163	=item ($rfh, $wfh) = IO::AIO::pipe2 [$flags]
		2164
		2165	This is a direct interface to the Linux L<pipe2(2)> system call. If
		2166	C<$flags> is missing or C<0>, then this should be the same as a call to
		2167	perl's built-in C<pipe> function and create a new pipe, and works on
		2168	systems that lack the pipe2 syscall. On win32, this case invokes C<_pipe
		2169	(..., 4096, O_BINARY)>.
		2170
		2171	If C<$flags> is non-zero, it tries to invoke the pipe2 system call with
		2172	the given flags (Linux 2.6.27, glibc 2.9).
		2173
		2174	On success, the read and write file handles are returned.
		2175
		2176	On error, nothing will be returned. If the pipe2 syscall is missing and
		2177	C<$flags> is non-zero, fails with C<ENOSYS>.
		2178
		2179	Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the
		2180	time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and
		2181	C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported.
2013		2182
2014	=back	2183	=back
2015		2184
2016	=cut	2185	=cut
2017		2186

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Comparing IO-AIO/AIO.pm (file contents): Revision 1.229 by root, Wed Jul 25 16:32:30 2012 UTC vs. Revision 1.263 by root, Tue Jul 12 20:46:33 2016 UTC

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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.229 by root, Wed Jul 25 16:32:30 2012 UTC vs.
Revision 1.263 by root, Tue Jul 12 20:46:33 2016 UTC