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

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.232 by root, Mon Jul 30 16:46:30 2012 UTC vs.
Revision 1.264 by root, Mon Jul 18 07:48:01 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
…		…
228	aio_unlink $pathname, $callback->($status)	227	aio_unlink $pathname, $callback->($status)
229	aio_mknod $pathname, $mode, $dev, $callback->($status)	228	aio_mknod $pathname, $mode, $dev, $callback->($status)
230	aio_link $srcpath, $dstpath, $callback->($status)	229	aio_link $srcpath, $dstpath, $callback->($status)
231	aio_symlink $srcpath, $dstpath, $callback->($status)	230	aio_symlink $srcpath, $dstpath, $callback->($status)
232	aio_readlink $pathname, $callback->($link)	231	aio_readlink $pathname, $callback->($link)
233	aio_realpath $pathname, $callback->($link)	232	aio_realpath $pathname, $callback->($path)
234	aio_rename $srcpath, $dstpath, $callback->($status)	233	aio_rename $srcpath, $dstpath, $callback->($status)
235	aio_mkdir $pathname, $mode, $callback->($status)	234	aio_mkdir $pathname, $mode, $callback->($status)
236	aio_rmdir $pathname, $callback->($status)	235	aio_rmdir $pathname, $callback->($status)
237	aio_readdir $pathname, $callback->($entries)	236	aio_readdir $pathname, $callback->($entries)
238	aio_readdirx $pathname, $flags, $callback->($entries, $flags)	237	aio_readdirx $pathname, $flags, $callback->($entries, $flags)
…		…
241	aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)	240	aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
242	aio_load $pathname, $data, $callback->($status)	241	aio_load $pathname, $data, $callback->($status)
243	aio_copy $srcpath, $dstpath, $callback->($status)	242	aio_copy $srcpath, $dstpath, $callback->($status)
244	aio_move $srcpath, $dstpath, $callback->($status)	243	aio_move $srcpath, $dstpath, $callback->($status)
245	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)
246	aio_sync $callback->($status)	247	aio_sync $callback->($status)
247	aio_syncfs $fh, $callback->($status)	248	aio_syncfs $fh, $callback->($status)
248	aio_fsync $fh, $callback->($status)	249	aio_fsync $fh, $callback->($status)
249	aio_fdatasync $fh, $callback->($status)	250	aio_fdatasync $fh, $callback->($status)
250	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)	251	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
…		…
362		363
363		364
364	=item aio_open $pathname, $flags, $mode, $callback->($fh)	365	=item aio_open $pathname, $flags, $mode, $callback->($fh)
365		366
366	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
367	created filehandle for the file.	368	created filehandle for the file (or C<undef> in case of an error).
368		369
369	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,
370	for an explanation.	371	for an explanation.
371		372
372	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
…		…
395	following POSIX and non-POSIX constants are available (missing ones on	396	following POSIX and non-POSIX constants are available (missing ones on
396	your system are, as usual, C<0>):	397	your system are, as usual, C<0>):
397		398
398	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>,
399	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>,
400	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>.
401		402
402		403
403	=item aio_close $fh, $callback->($status)	404	=item aio_close $fh, $callback->($status)
404		405
405	Asynchronously close a file and call the callback with the result	406	Asynchronously close a file and call the callback with the result
…		…
509	As native sendfile syscalls (as practically any non-POSIX interface hacked	510	As native sendfile syscalls (as practically any non-POSIX interface hacked
510	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
511	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
512	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,
513	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> -
514	fewre bytes than expected might have been transferred.	515	fewer bytes than expected might have been transferred.
515		516
516		517
517	=item aio_readahead $fh,$offset,$length, $callback->($retval)	518	=item aio_readahead $fh,$offset,$length, $callback->($retval)
518		519
519	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
…		…
523	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
524	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
525	(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
526	file. The current file offset of the file is left unchanged.	527	file. The current file offset of the file is left unchanged.
527		528
528	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
529	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.
530		531
531		532
532	=item aio_stat $fh_or_path, $callback->($status)	533	=item aio_stat $fh_or_path, $callback->($status)
533		534
534	=item aio_lstat $fh, $callback->($status)	535	=item aio_lstat $fh, $callback->($status)
…		…
603	namemax => 255,	604	namemax => 255,
604	frsize => 1024,	605	frsize => 1024,
605	fsid => 1810	606	fsid => 1810
606	}	607	}
607		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
608		693
609	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	694	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
610		695
611	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
612	and $mtime being undef). Fractional times are supported if the underlying	697	and $mtime being undef). Fractional times are supported if the underlying
…		…
642	Works like truncate(2) or ftruncate(2).	727	Works like truncate(2) or ftruncate(2).
643		728
644		729
645	=item aio_allocate $fh, $mode, $offset, $len, $callback->($status)	730	=item aio_allocate $fh, $mode, $offset, $len, $callback->($status)
646		731
647	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
648	linux C<fallocate> docuemntation for details.	733	linux C<fallocate> documentation for details.
649		734
650	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
651	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>,
652	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).
653		742
654	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
655	C<f_bsize> returned by C<statvfs>.	744	C<f_bsize> returned by C<statvfs>.
656		745
657	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
…		…
702		791
703		792
704	=item aio_realpath $pathname, $callback->($path)	793	=item aio_realpath $pathname, $callback->($path)
705		794
706	Asynchronously make the path absolute and resolve any symlinks in	795	Asynchronously make the path absolute and resolve any symlinks in
707	C<$path>. The resulting path only consists of directories (Same as	796	C<$path>. The resulting path only consists of directories (same as
708	L<Cwd::realpath>).	797	L<Cwd::realpath>).
709		798
710	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
711	directory by passing it a path of F<.> (a single dot).	800	directory by passing it a path of F<.> (a single dot).
712		801
713		802
714	=item aio_rename $srcpath, $dstpath, $callback->($status)	803	=item aio_rename $srcpath, $dstpath, $callback->($status)
715		804
716	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
717	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>.
718		811
719		812
720	=item aio_mkdir $pathname, $mode, $callback->($status)	813	=item aio_mkdir $pathname, $mode, $callback->($status)
721		814
722	Asynchronously mkdir (create) a directory and call the callback with	815	Asynchronously mkdir (create) a directory and call the callback with
…		…
726		819
727	=item aio_rmdir $pathname, $callback->($status)	820	=item aio_rmdir $pathname, $callback->($status)
728		821
729	Asynchronously rmdir (delete) a directory and call the callback with the	822	Asynchronously rmdir (delete) a directory and call the callback with the
730	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>.
731		828
732		829
733	=item aio_readdir $pathname, $callback->($entries)	830	=item aio_readdir $pathname, $callback->($entries)
734		831
735	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
…		…
1100	}	1197	}
1101		1198
1102	=item aio_rmtree $pathname, $callback->($status)	1199	=item aio_rmtree $pathname, $callback->($status)
1103		1200
1104	Delete a directory tree starting (and including) C<$path>, return the	1201	Delete a directory tree starting (and including) C<$path>, return the
1105	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
1106	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
1107	everything else.	1204	everything else.
1108		1205
1109	=cut	1206	=cut
1110		1207
…		…
1131	add $grp $dirgrp;	1228	add $grp $dirgrp;
1132	};	1229	};
1133		1230
1134	$grp	1231	$grp
1135	}	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.
		1252
		1253	The following constants are available (missing ones are, as usual C<0>):
		1254
		1255	C<FIFREEZE>, C<FITHAW>, C<FITRIM>, C<FICLONE>, C<FICLONERANGE>, C<FIDEDUPERANGE>.
		1256
		1257	C<FS_IOC_GETFLAGS>, C<FS_IOC_SETFLAGS>, C<FS_IOC_GETVERSION>, C<FS_IOC_SETVERSION>,
		1258	C<FS_IOC_FIEMAP>.
		1259
		1260	C<FS_IOC_FSGETXATTR>, C<FS_IOC_FSSETXATTR>, C<FS_IOC_SET_ENCRYPTION_POLICY>,
		1261	C<FS_IOC_GET_ENCRYPTION_PWSALT>, C<FS_IOC_GET_ENCRYPTION_POLICY>, C<FS_KEY_DESCRIPTOR_SIZE>.
		1262
		1263	C<FS_SECRM_FL>, C<FS_UNRM_FL>, C<FS_COMPR_FL>, C<FS_SYNC_FL>, C<FS_IMMUTABLE_FL>,
		1264	C<FS_APPEND_FL>, C<FS_NODUMP_FL>, C<FS_NOATIME_FL>, C<FS_DIRTY_FL>,
		1265	C<FS_COMPRBLK_FL>, C<FS_NOCOMP_FL>, C<FS_ENCRYPT_FL>, C<FS_BTREE_FL>,
		1266	C<FS_INDEX_FL>, C<FS_JOURNAL_DATA_FL>, C<FS_NOTAIL_FL>, C<FS_DIRSYNC_FL>, C<FS_TOPDIR_FL>,
		1267	C<FS_FL_USER_MODIFIABLE>.
		1268
		1269	C<FS_XFLAG_REALTIME>, C<FS_XFLAG_PREALLOC>, C<FS_XFLAG_IMMUTABLE>, C<FS_XFLAG_APPEND>,
		1270	C<FS_XFLAG_SYNC>, C<FS_XFLAG_NOATIME>, C<FS_XFLAG_NODUMP>, C<FS_XFLAG_RTINHERIT>,
		1271	C<FS_XFLAG_PROJINHERIT>, C<FS_XFLAG_NOSYMLINKS>, C<FS_XFLAG_EXTSIZE>, C<FS_XFLAG_EXTSZINHERIT>,
		1272	C<FS_XFLAG_NODEFRAG>, C<FS_XFLAG_FILESTREAM>, C<FS_XFLAG_DAX>, C<FS_XFLAG_HASATTR>,
1136		1273
1137	=item aio_sync $callback->($status)	1274	=item aio_sync $callback->($status)
1138		1275
1139	Asynchronously call sync and call the callback when finished.	1276	Asynchronously call sync and call the callback when finished.
1140		1277
…		…
1230		1367
1231	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1368	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
1232	scalars.	1369	scalars.
1233		1370
1234	It touches (reads or writes) all memory pages in the specified	1371	It touches (reads or writes) all memory pages in the specified
1235	range inside the scalar. All caveats and parameters are the same	1372	range inside the scalar. All caveats and parameters are the same
1236	as for C<aio_msync>, above, except for flags, which must be either	1373	as for C<aio_msync>, above, except for flags, which must be either
1237	C<0> (which reads all pages and ensures they are instantiated) or	1374	C<0> (which reads all pages and ensures they are instantiated) or
1238	C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and	1375	C<IO::AIO::MT_MODIFY>, which modifies the memory pages (by reading and
1239	writing an octet from it, which dirties the page).	1376	writing an octet from it, which dirties the page).
1240		1377
1241	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)	1378	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
1242		1379
1243	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1380	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
…		…
1277		1414
1278	aio_mlockall IO::AIO::MCL_FUTURE;	1415	aio_mlockall IO::AIO::MCL_FUTURE;
1279		1416
1280	=item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)	1417	=item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
1281		1418
1282	Queries the extents of the given file (by calling the Linux FIEMAP ioctl,	1419	Queries the extents of the given file (by calling the Linux C<FIEMAP>
1283	see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If the	1420	ioctl, see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If
1284	C<ioctl> is not available on your OS, then this request will fail with	1421	the ioctl is not available on your OS, then this request will fail with
1285	C<ENOSYS>.	1422	C<ENOSYS>.
1286		1423
1287	C<$start> is the starting offset to query extents for, C<$length> is the	1424	C<$start> is the starting offset to query extents for, C<$length> is the
1288	size of the range to query - if it is C<undef>, then the whole file will	1425	size of the range to query - if it is C<undef>, then the whole file will
1289	be queried.	1426	be queried.
…		…
1412	aio_stat [$etcdir, "passwd"], sub {	1549	aio_stat [$etcdir, "passwd"], sub {
1413	# yay	1550	# yay
1414	};	1551	};
1415	};	1552	};
1416		1553
1417	That C<aio_wd> is a request and not a normal function shows that creating	1554	The fact that C<aio_wd> is a request and not a normal function shows that
1418	an IO::AIO::WD object is itself a potentially blocking operation, which is	1555	creating an IO::AIO::WD object is itself a potentially blocking operation,
1419	why it is done asynchronously.	1556	which is why it is done asynchronously.
1420		1557
1421	To stat the directory obtained with C<aio_wd> above, one could write	1558	To stat the directory obtained with C<aio_wd> above, one could write
1422	either of the following three request calls:	1559	either of the following three request calls:
1423		1560
1424	aio_lstat "/etc" , sub { ... # pathname as normal string	1561	aio_lstat "/etc" , sub { ... # pathname as normal string
…		…
1444	will still point to the original directory. Most functions accepting a	1581	will still point to the original directory. Most functions accepting a
1445	pathname will use the directory fd on newer systems, and the string on	1582	pathname will use the directory fd on newer systems, and the string on
1446	older systems. Some functions (such as realpath) will always rely on the	1583	older systems. Some functions (such as realpath) will always rely on the
1447	string form of the pathname.	1584	string form of the pathname.
1448		1585
1449	So this fucntionality is mainly useful to get some protection against	1586	So this functionality is mainly useful to get some protection against
1450	C<chdir>, to easily get an absolute path out of a relative path for future	1587	C<chdir>, to easily get an absolute path out of a relative path for future
1451	reference, and to speed up doing many operations in the same directory	1588	reference, and to speed up doing many operations in the same directory
1452	(e.g. when stat'ing all files in a directory).	1589	(e.g. when stat'ing all files in a directory).
1453		1590
1454	The following functions implement this working directory abstraction:	1591	The following functions implement this working directory abstraction:
…		…
1467	passing C<undef> as working directory component of a pathname fails the	1604	passing C<undef> as working directory component of a pathname fails the
1468	request with C<ENOENT>, there is often no need for error checking in the	1605	request with C<ENOENT>, there is often no need for error checking in the
1469	C<aio_wd> callback, as future requests using the value will fail in the	1606	C<aio_wd> callback, as future requests using the value will fail in the
1470	expected way.	1607	expected way.
1471		1608
1472	If this call isn't available because your OS lacks it or it couldn't be
1473	detected, it will be emulated by calling C<fsync> instead.
1474
1475	=item IO::AIO::CWD	1609	=item IO::AIO::CWD
1476		1610
1477	This is a compiletime constant (object) that represents the process	1611	This is a compiletime constant (object) that represents the process
1478	current working directory.	1612	current working directory.
1479		1613
1480	Specifying this object as working directory object for a pathname is as	1614	Specifying this object as working directory object for a pathname is as if
1481	if the pathname would be specified directly, without a directory object,	1615	the pathname would be specified directly, without a directory object. For
1482	e.g., these calls are functionally identical:	1616	example, these calls are functionally identical:
1483		1617
1484	aio_stat "somefile", sub { ... };	1618	aio_stat "somefile", sub { ... };
1485	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };	1619	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };
1486		1620
1487	=back	1621	=back
1488		1622
		1623	To recover the path associated with an IO::AIO::WD object, you can use
		1624	C<aio_realpath>:
		1625
		1626	aio_realpath $wd, sub {
		1627	warn "path is $_[0]\n";
		1628	};
		1629
		1630	Currently, C<aio_statvfs> always, and C<aio_rename> and C<aio_rmdir>
		1631	sometimes, fall back to using an absolue path.
1489		1632
1490	=head2 IO::AIO::REQ CLASS	1633	=head2 IO::AIO::REQ CLASS
1491		1634
1492	All non-aggregate C<aio_*> functions return an object of this class when	1635	All non-aggregate C<aio_*> functions return an object of this class when
1493	called in non-void context.	1636	called in non-void context.
…		…
1671		1814
1672	See C<poll_cb> for an example.	1815	See C<poll_cb> for an example.
1673		1816
1674	=item IO::AIO::poll_cb	1817	=item IO::AIO::poll_cb
1675		1818
1676	Process some outstanding events on the result pipe. You have to call	1819	Process some requests that have reached the result phase (i.e. they have
		1820	been executed but the results are not yet reported). You have to call
		1821	this "regularly" to finish outstanding requests.
		1822
1677	this regularly. Returns C<0> if all events could be processed (or there	1823	Returns C<0> if all events could be processed (or there were no
1678	were no events to process), or C<-1> if it returned earlier for whatever	1824	events to process), or C<-1> if it returned earlier for whatever
1679	reason. Returns immediately when no events are outstanding. The amount of	1825	reason. Returns immediately when no events are outstanding. The amount
1680	events processed depends on the settings of C<IO::AIO::max_poll_req> and	1826	of events processed depends on the settings of C<IO::AIO::max_poll_req>,
1681	C<IO::AIO::max_poll_time>.	1827	C<IO::AIO::max_poll_time> and C<IO::AIO::max_outstanding>.
1682		1828
1683	If not all requests were processed for whatever reason, the filehandle	1829	If not all requests were processed for whatever reason, the poll file
1684	will still be ready when C<poll_cb> returns, so normally you don't have to	1830	descriptor will still be ready when C<poll_cb> returns, so normally you
1685	do anything special to have it called later.	1831	don't have to do anything special to have it called later.
1686		1832
1687	Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes	1833	Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes
1688	ready, it can be beneficial to call this function from loops which submit	1834	ready, it can be beneficial to call this function from loops which submit
1689	a lot of requests, to make sure the results get processed when they become	1835	a lot of requests, to make sure the results get processed when they become
1690	available and not just when the loop is finished and the event loop takes	1836	available and not just when the loop is finished and the event loop takes
…		…
1699	poll => 'r', async => 1,	1845	poll => 'r', async => 1,
1700	cb => \&IO::AIO::poll_cb);	1846	cb => \&IO::AIO::poll_cb);
1701		1847
1702	=item IO::AIO::poll_wait	1848	=item IO::AIO::poll_wait
1703		1849
1704	If there are any outstanding requests and none of them in the result	1850	Wait until either at least one request is in the result phase or no
1705	phase, wait till the result filehandle becomes ready for reading (simply	1851	requests are outstanding anymore.
1706	does a C<select> on the filehandle. This is useful if you want to	1852
1707	synchronously wait for some requests to finish).	1853	This is useful if you want to synchronously wait for some requests to
		1854	become ready, without actually handling them.
1708		1855
1709	See C<nreqs> for an example.	1856	See C<nreqs> for an example.
1710		1857
1711	=item IO::AIO::poll	1858	=item IO::AIO::poll
1712		1859
…		…
1833		1980
1834	This is a very bad function to use in interactive programs because it	1981	This is a very bad function to use in interactive programs because it
1835	blocks, and a bad way to reduce concurrency because it is inexact: Better	1982	blocks, and a bad way to reduce concurrency because it is inexact: Better
1836	use an C<aio_group> together with a feed callback.	1983	use an C<aio_group> together with a feed callback.
1837		1984
1838	It's main use is in scripts without an event loop - when you want to stat	1985	Its main use is in scripts without an event loop - when you want to stat
1839	a lot of files, you can write somehting like this:	1986	a lot of files, you can write somehting like this:
1840		1987
1841	IO::AIO::max_outstanding 32;	1988	IO::AIO::max_outstanding 32;
1842		1989
1843	for my $path (...) {	1990	for my $path (...) {
…		…
1883		2030
1884	=back	2031	=back
1885		2032
1886	=head3 MISCELLANEOUS FUNCTIONS	2033	=head3 MISCELLANEOUS FUNCTIONS
1887		2034
1888	IO::AIO implements some functions that might be useful, but are not	2035	IO::AIO implements some functions that are useful when you want to use
1889	asynchronous.	2036	some "Advanced I/O" function not available to in Perl, without going the
		2037	"Asynchronous I/O" route. Many of these have an asynchronous C<aio_*>
		2038	counterpart.
1890		2039
1891	=over 4	2040	=over 4
1892		2041
1893	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count	2042	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
1894		2043
…		…
1913	=item IO::AIO::madvise $scalar, $offset, $len, $advice	2062	=item IO::AIO::madvise $scalar, $offset, $len, $advice
1914		2063
1915	Simply calls the C<posix_madvise> function (see its	2064	Simply calls the C<posix_madvise> function (see its
1916	manpage for details). The following advice constants are	2065	manpage for details). The following advice constants are
1917	available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,	2066	available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,
1918	C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>.	2067	C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>,
		2068	C<IO::AIO::MADV_FREE>.
1919		2069
1920	On systems that do not implement C<posix_madvise>, this function returns	2070	On systems that do not implement C<posix_madvise>, this function returns
1921	ENOSYS, otherwise the return value of C<posix_madvise>.	2071	ENOSYS, otherwise the return value of C<posix_madvise>.
1922		2072
1923	=item IO::AIO::mprotect $scalar, $offset, $len, $protect	2073	=item IO::AIO::mprotect $scalar, $offset, $len, $protect
…		…
1953	filesize.	2103	filesize.
1954		2104
1955	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,	2105	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,
1956	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,	2106	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,
1957		2107
1958	C<$flags> can be a combination of C<IO::AIO::MAP_SHARED> or	2108	C<$flags> can be a combination of
1959	C<IO::AIO::MAP_PRIVATE>, or a number of system-specific flags (when	2109	C<IO::AIO::MAP_SHARED> or
1960	not available, the are defined as 0): C<IO::AIO::MAP_ANONYMOUS>	2110	C<IO::AIO::MAP_PRIVATE>,
		2111	or a number of system-specific flags (when not available, the are C<0>):
1961	(which is set to C<MAP_ANON> if your system only provides this	2112	C<IO::AIO::MAP_ANONYMOUS> (which is set to C<MAP_ANON> if your system only provides this constant),
1962	constant), C<IO::AIO::MAP_HUGETLB>, C<IO::AIO::MAP_LOCKED>,	2113	C<IO::AIO::MAP_LOCKED>,
1963	C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or	2114	C<IO::AIO::MAP_NORESERVE>,
		2115	C<IO::AIO::MAP_POPULATE>,
1964	C<IO::AIO::MAP_NONBLOCK>	2116	C<IO::AIO::MAP_NONBLOCK>,
		2117	C<IO::AIO::MAP_FIXED>,
		2118	C<IO::AIO::MAP_GROWSDOWN>,
		2119	C<IO::AIO::MAP_32BIT>,
		2120	C<IO::AIO::MAP_HUGETLB> or
		2121	C<IO::AIO::MAP_STACK>.
1965		2122
1966	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.	2123	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.
1967		2124
1968	C<$offset> is the offset from the start of the file - it generally must be	2125	C<$offset> is the offset from the start of the file - it generally must be
1969	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.	2126	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.
…		…
2012		2169
2013	See the C<splice(2)> manpage for details.	2170	See the C<splice(2)> manpage for details.
2014		2171
2015	=item IO::AIO::tee $r_fh, $w_fh, $length, $flags	2172	=item IO::AIO::tee $r_fh, $w_fh, $length, $flags
2016		2173
2017	Calls the GNU/Linux C<tee(2)> syscall, see it's manpage and the	2174	Calls the GNU/Linux C<tee(2)> syscall, see its manpage and the
2018	description for C<IO::AIO::splice> above for details.	2175	description for C<IO::AIO::splice> above for details.
		2176
		2177	=item $actual_size = IO::AIO::pipesize $r_fh[, $new_size]
		2178
		2179	Attempts to query or change the pipe buffer size. Obviously works only
		2180	on pipes, and currently works only on GNU/Linux systems, and fails with
		2181	C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer
		2182	size on other systems, drop me a note.
		2183
		2184	=item ($rfh, $wfh) = IO::AIO::pipe2 [$flags]
		2185
		2186	This is a direct interface to the Linux L<pipe2(2)> system call. If
		2187	C<$flags> is missing or C<0>, then this should be the same as a call to
		2188	perl's built-in C<pipe> function and create a new pipe, and works on
		2189	systems that lack the pipe2 syscall. On win32, this case invokes C<_pipe
		2190	(..., 4096, O_BINARY)>.
		2191
		2192	If C<$flags> is non-zero, it tries to invoke the pipe2 system call with
		2193	the given flags (Linux 2.6.27, glibc 2.9).
		2194
		2195	On success, the read and write file handles are returned.
		2196
		2197	On error, nothing will be returned. If the pipe2 syscall is missing and
		2198	C<$flags> is non-zero, fails with C<ENOSYS>.
		2199
		2200	Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the
		2201	time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and
		2202	C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported.
2019		2203
2020	=back	2204	=back
2021		2205
2022	=cut	2206	=cut
2023		2207

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Comparing IO-AIO/AIO.pm (file contents): Revision 1.232 by root, Mon Jul 30 16:46:30 2012 UTC vs. Revision 1.264 by root, Mon Jul 18 07:48:01 2016 UTC

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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.232 by root, Mon Jul 30 16:46:30 2012 UTC vs.
Revision 1.264 by root, Mon Jul 18 07:48:01 2016 UTC