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

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.238 by root, Thu Oct 11 05:01:56 2012 UTC vs.
Revision 1.271 by root, Fri Jun 23 21:43:51 2017 UTC

…		…
1	=head1 NAME	1	=head1 NAME
2		2
3	IO::AIO - Asynchronous Input/Output	3	IO::AIO - Asynchronous/Advanced Input/Output
4		4
5	=head1 SYNOPSIS	5	=head1 SYNOPSIS
6		6
7	use IO::AIO;	7	use IO::AIO;
8		8
58	not well-supported or restricted (GNU/Linux doesn't allow them on normal	58	not well-supported or restricted (GNU/Linux doesn't allow them on normal
59	files currently, for example), and they would only support aio_read and	59	files currently, for example), and they would only support aio_read and
60	aio_write, so the remaining functionality would have to be implemented	60	aio_write, so the remaining functionality would have to be implemented
61	using threads anyway.	61	using threads anyway.
62		62
		63	In addition to asynchronous I/O, this module also exports some rather
		64	arcane interfaces, such as C<madvise> or linux's C<splice> system call,
		65	which is why the C<A> in C<AIO> can also mean I<advanced>.
		66
63	Although the module will work in the presence of other (Perl-) threads,	67	Although the module will work in the presence of other (Perl-) threads,
64	it is currently not reentrant in any way, so use appropriate locking	68	it is currently not reentrant in any way, so use appropriate locking
65	yourself, always call C<poll_cb> from within the same thread, or never	69	yourself, always call C<poll_cb> from within the same thread, or never
66	call C<poll_cb> (or other C<aio_> functions) recursively.	70	call C<poll_cb> (or other C<aio_> functions) recursively.
67		71
68	=head2 EXAMPLE	72	=head2 EXAMPLE
69		73
70	This is a simple example that uses the EV module and loads	74	This is a simple example that uses the EV module and loads
71	F</etc/passwd> asynchronously:	75	F</etc/passwd> asynchronously:
72		76
73	use Fcntl;
74	use EV;	77	use EV;
75	use IO::AIO;	78	use IO::AIO;
76		79
77	# register the IO::AIO callback with EV	80	# register the IO::AIO callback with EV
78	my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;	81	my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
…		…
95		98
96	# file contents now in $contents	99	# file contents now in $contents
97	print $contents;	100	print $contents;
98		101
99	# exit event loop and program	102	# exit event loop and program
100	EV::unloop;	103	EV::break;
101	};	104	};
102	};	105	};
103		106
104	# possibly queue up other requests, or open GUI windows,	107	# possibly queue up other requests, or open GUI windows,
105	# check for sockets etc. etc.	108	# check for sockets etc. etc.
106		109
107	# process events as long as there are some:	110	# process events as long as there are some:
108	EV::loop;	111	EV::run;
109		112
110	=head1 REQUEST ANATOMY AND LIFETIME	113	=head1 REQUEST ANATOMY AND LIFETIME
111		114
112	Every C<aio_*> function creates a request. which is a C data structure not	115	Every C<aio_*> function creates a request. which is a C data structure not
113	directly visible to Perl.	116	directly visible to Perl.
…		…
168	use common::sense;	171	use common::sense;
169		172
170	use base 'Exporter';	173	use base 'Exporter';
171		174
172	BEGIN {	175	BEGIN {
173	our $VERSION = '4.18';	176	our $VERSION = 4.35;
174		177
175	our @AIO_REQ = qw(aio_sendfile aio_seek aio_read aio_write aio_open aio_close	178	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	179	aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx
177	aio_scandir aio_symlink aio_readlink aio_realpath aio_sync	180	aio_scandir aio_symlink aio_readlink aio_realpath aio_fcntl aio_ioctl
178	aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range aio_allocate	181	aio_sync aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range
179	aio_pathsync aio_readahead aio_fiemap	182	aio_pathsync aio_readahead aio_fiemap aio_allocate
180	aio_rename aio_link aio_move aio_copy aio_group	183	aio_rename aio_rename2 aio_link aio_move aio_copy aio_group
181	aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown	184	aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown
182	aio_chmod aio_utime aio_truncate	185	aio_chmod aio_utime aio_truncate
183	aio_msync aio_mtouch aio_mlock aio_mlockall	186	aio_msync aio_mtouch aio_mlock aio_mlockall
184	aio_statvfs	187	aio_statvfs
185	aio_wd);	188	aio_wd);
…		…
228	aio_unlink $pathname, $callback->($status)	231	aio_unlink $pathname, $callback->($status)
229	aio_mknod $pathname, $mode, $dev, $callback->($status)	232	aio_mknod $pathname, $mode, $dev, $callback->($status)
230	aio_link $srcpath, $dstpath, $callback->($status)	233	aio_link $srcpath, $dstpath, $callback->($status)
231	aio_symlink $srcpath, $dstpath, $callback->($status)	234	aio_symlink $srcpath, $dstpath, $callback->($status)
232	aio_readlink $pathname, $callback->($link)	235	aio_readlink $pathname, $callback->($link)
233	aio_realpath $pathname, $callback->($link)	236	aio_realpath $pathname, $callback->($path)
234	aio_rename $srcpath, $dstpath, $callback->($status)	237	aio_rename $srcpath, $dstpath, $callback->($status)
		238	aio_rename2 $srcpath, $dstpath, $flags, $callback->($status)
235	aio_mkdir $pathname, $mode, $callback->($status)	239	aio_mkdir $pathname, $mode, $callback->($status)
236	aio_rmdir $pathname, $callback->($status)	240	aio_rmdir $pathname, $callback->($status)
237	aio_readdir $pathname, $callback->($entries)	241	aio_readdir $pathname, $callback->($entries)
238	aio_readdirx $pathname, $flags, $callback->($entries, $flags)	242	aio_readdirx $pathname, $flags, $callback->($entries, $flags)
239	IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST	243	IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST
…		…
241	aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)	245	aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
242	aio_load $pathname, $data, $callback->($status)	246	aio_load $pathname, $data, $callback->($status)
243	aio_copy $srcpath, $dstpath, $callback->($status)	247	aio_copy $srcpath, $dstpath, $callback->($status)
244	aio_move $srcpath, $dstpath, $callback->($status)	248	aio_move $srcpath, $dstpath, $callback->($status)
245	aio_rmtree $pathname, $callback->($status)	249	aio_rmtree $pathname, $callback->($status)
		250	aio_fcntl $fh, $cmd, $arg, $callback->($status)
		251	aio_ioctl $fh, $request, $buf, $callback->($status)
246	aio_sync $callback->($status)	252	aio_sync $callback->($status)
247	aio_syncfs $fh, $callback->($status)	253	aio_syncfs $fh, $callback->($status)
248	aio_fsync $fh, $callback->($status)	254	aio_fsync $fh, $callback->($status)
249	aio_fdatasync $fh, $callback->($status)	255	aio_fdatasync $fh, $callback->($status)
250	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)	256	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
251	aio_pathsync $pathname, $callback->($status)	257	aio_pathsync $pathname, $callback->($status)
252	aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	258	aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status)
253	aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	259	aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
254	aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)	260	aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
255	aio_mlockall $flags, $callback->($status)	261	aio_mlockall $flags, $callback->($status)
256	aio_group $callback->(...)	262	aio_group $callback->(...)
257	aio_nop $callback->()	263	aio_nop $callback->()
…		…
395	following POSIX and non-POSIX constants are available (missing ones on	401	following POSIX and non-POSIX constants are available (missing ones on
396	your system are, as usual, C<0>):	402	your system are, as usual, C<0>):
397		403
398	C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,	404	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>,	405	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>.	406	C<O_RSYNC>, C<O_SYNC>, C<O_PATH>, C<O_TMPFILE>, and C<O_TTY_INIT>.
401		407
402		408
403	=item aio_close $fh, $callback->($status)	409	=item aio_close $fh, $callback->($status)
404		410
405	Asynchronously close a file and call the callback with the result	411	Asynchronously close a file and call the callback with the result
…		…
440	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	446	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
441		447
442	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	448	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
443		449
444	Reads or writes C<$length> bytes from or to the specified C<$fh> and	450	Reads or writes C<$length> bytes from or to the specified C<$fh> and
445	C<$offset> into the scalar given by C<$data> and offset C<$dataoffset>	451	C<$offset> into the scalar given by C<$data> and offset C<$dataoffset> and
446	and calls the callback without the actual number of bytes read (or -1 on	452	calls the callback with the actual number of bytes transferred (or -1 on
447	error, just like the syscall).	453	error, just like the syscall).
448		454
449	C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to	455	C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to
450	offset plus the actual number of bytes read.	456	offset plus the actual number of bytes read.
451		457
…		…
509	As native sendfile syscalls (as practically any non-POSIX interface hacked	515	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	516	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	517	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,	518	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> -	519	so you really really should check the return value of C<aio_sendfile> -
514	fewre bytes than expected might have been transferred.	520	fewer bytes than expected might have been transferred.
515		521
516		522
517	=item aio_readahead $fh,$offset,$length, $callback->($retval)	523	=item aio_readahead $fh,$offset,$length, $callback->($retval)
518		524
519	C<aio_readahead> populates the page cache with data from a file so that	525	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	529	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	530	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	531	(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.	532	file. The current file offset of the file is left unchanged.
527		533
528	If that syscall doesn't exist (likely if your OS isn't Linux) it will be	534	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.	535	be emulated by simply reading the data, which would have a similar effect.
530		536
531		537
532	=item aio_stat $fh_or_path, $callback->($status)	538	=item aio_stat $fh_or_path, $callback->($status)
533		539
534	=item aio_lstat $fh, $callback->($status)	540	=item aio_lstat $fh, $callback->($status)
…		…
603	namemax => 255,	609	namemax => 255,
604	frsize => 1024,	610	frsize => 1024,
605	fsid => 1810	611	fsid => 1810
606	}	612	}
607		613
608	Here is a (likely partial) list of fsid values used by Linux - it is safe	614	Here is a (likely partial - send me updates!) list of fsid values used by
609	to hardcode these when the $^O is C<linux>:	615	Linux - it is safe to hardcode these when C<$^O> is C<linux>:
610		616
611	0x0000adf5 adfs	617	0x0000adf5 adfs
612	0x0000adff affs	618	0x0000adff affs
613	0x5346414f afs	619	0x5346414f afs
614	0x09041934 anon-inode filesystem	620	0x09041934 anon-inode filesystem
…		…
627	0x00001373 devfs	633	0x00001373 devfs
628	0x00001cd1 devpts	634	0x00001cd1 devpts
629	0x0000f15f ecryptfs	635	0x0000f15f ecryptfs
630	0x00414a53 efs	636	0x00414a53 efs
631	0x0000137d ext	637	0x0000137d ext
632	0x0000ef53 ext2/ext3	638	0x0000ef53 ext2/ext3/ext4
633	0x0000ef51 ext2	639	0x0000ef51 ext2
		640	0xf2f52010 f2fs
634	0x00004006 fat	641	0x00004006 fat
635	0x65735546 fuseblk	642	0x65735546 fuseblk
636	0x65735543 fusectl	643	0x65735543 fusectl
637	0x0bad1dea futexfs	644	0x0bad1dea futexfs
638	0x01161970 gfs2	645	0x01161970 gfs2
639	0x47504653 gpfs	646	0x47504653 gpfs
640	0x00004244 hfs	647	0x00004244 hfs
641	0xf995e849 hpfs	648	0xf995e849 hpfs
		649	0x00c0ffee hostfs
642	0x958458f6 hugetlbfs	650	0x958458f6 hugetlbfs
643	0x2bad1dea inotifyfs	651	0x2bad1dea inotifyfs
644	0x00009660 isofs	652	0x00009660 isofs
645	0x000072b6 jffs2	653	0x000072b6 jffs2
646	0x3153464a jfs	654	0x3153464a jfs
…		…
661	0x00009fa1 openprom	669	0x00009fa1 openprom
662	0x7461636F ocfs2	670	0x7461636F ocfs2
663	0x00009fa0 proc	671	0x00009fa0 proc
664	0x6165676c pstorefs	672	0x6165676c pstorefs
665	0x0000002f qnx4	673	0x0000002f qnx4
		674	0x68191122 qnx6
666	0x858458f6 ramfs	675	0x858458f6 ramfs
667	0x52654973 reiserfs	676	0x52654973 reiserfs
668	0x00007275 romfs	677	0x00007275 romfs
669	0x67596969 rpc_pipefs	678	0x67596969 rpc_pipefs
670	0x73636673 securityfs	679	0x73636673 securityfs
…		…
723	Works like truncate(2) or ftruncate(2).	732	Works like truncate(2) or ftruncate(2).
724		733
725		734
726	=item aio_allocate $fh, $mode, $offset, $len, $callback->($status)	735	=item aio_allocate $fh, $mode, $offset, $len, $callback->($status)
727		736
728	Allocates or freed disk space according to the C<$mode> argument. See the	737	Allocates or frees disk space according to the C<$mode> argument. See the
729	linux C<fallocate> docuemntation for details.	738	linux C<fallocate> documentation for details.
730		739
731	C<$mode> can currently be C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE>	740	C<$mode> is usually C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> to allocate
732	to allocate space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE \|	741	space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE \| IO::AIO::FALLOC_FL_KEEP_SIZE>,
733	IO::AIO::FALLOC_FL_KEEP_SIZE>, to deallocate a file range.	742	to deallocate a file range.
		743
		744	IO::AIO also supports C<FALLOC_FL_COLLAPSE_RANGE>, to remove a range
		745	(without leaving a hole) and C<FALLOC_FL_ZERO_RANGE>, to zero a range (see
		746	your L<fallocate(2)> manpage).
734		747
735	The file system block size used by C<fallocate> is presumably the	748	The file system block size used by C<fallocate> is presumably the
736	C<f_bsize> returned by C<statvfs>.	749	C<f_bsize> returned by C<statvfs>.
737		750
738	If C<fallocate> isn't available or cannot be emulated (currently no	751	If C<fallocate> isn't available or cannot be emulated (currently no
…		…
783		796
784		797
785	=item aio_realpath $pathname, $callback->($path)	798	=item aio_realpath $pathname, $callback->($path)
786		799
787	Asynchronously make the path absolute and resolve any symlinks in	800	Asynchronously make the path absolute and resolve any symlinks in
788	C<$path>. The resulting path only consists of directories (Same as	801	C<$path>. The resulting path only consists of directories (same as
789	L<Cwd::realpath>).	802	L<Cwd::realpath>).
790		803
791	This request can be used to get the absolute path of the current working	804	This request can be used to get the absolute path of the current working
792	directory by passing it a path of F<.> (a single dot).	805	directory by passing it a path of F<.> (a single dot).
793		806
794		807
795	=item aio_rename $srcpath, $dstpath, $callback->($status)	808	=item aio_rename $srcpath, $dstpath, $callback->($status)
796		809
797	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as	810	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as
798	rename(2) and call the callback with the result code.	811	rename(2) and call the callback with the result code.
		812
		813	On systems that support the AIO::WD working directory abstraction
		814	natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead
		815	of failing, C<rename> is called on the absolute path of C<$wd>.
		816
		817
		818	=item aio_rename2 $srcpath, $dstpath, $flags, $callback->($status)
		819
		820	Basically a version of C<aio_rename> with an additional C<$flags>
		821	argument. Calling this with C<$flags=0> is the same as calling
		822	C<aio_rename>.
		823
		824	Non-zero flags are currently only supported on GNU/Linux systems that
		825	support renameat2. Other systems fail with C<ENOSYS> in this case.
		826
		827	The following constants are available (missing ones are, as usual C<0>),
		828	see renameat2(2) for details:
		829
		830	C<IO::AIO::RENAME_NOREPLACE>, C<IO::AIO::RENAME_EXCHANGE>
		831	and C<IO::AIO::RENAME_WHITEOUT>.
799		832
800		833
801	=item aio_mkdir $pathname, $mode, $callback->($status)	834	=item aio_mkdir $pathname, $mode, $callback->($status)
802		835
803	Asynchronously mkdir (create) a directory and call the callback with	836	Asynchronously mkdir (create) a directory and call the callback with
…		…
807		840
808	=item aio_rmdir $pathname, $callback->($status)	841	=item aio_rmdir $pathname, $callback->($status)
809		842
810	Asynchronously rmdir (delete) a directory and call the callback with the	843	Asynchronously rmdir (delete) a directory and call the callback with the
811	result code.	844	result code.
		845
		846	On systems that support the AIO::WD working directory abstraction
		847	natively, the case C<[$wd, "."]> is specialcased - instead of failing,
		848	C<rmdir> is called on the absolute path of C<$wd>.
812		849
813		850
814	=item aio_readdir $pathname, $callback->($entries)	851	=item aio_readdir $pathname, $callback->($entries)
815		852
816	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire	853	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire
…		…
1181	}	1218	}
1182		1219
1183	=item aio_rmtree $pathname, $callback->($status)	1220	=item aio_rmtree $pathname, $callback->($status)
1184		1221
1185	Delete a directory tree starting (and including) C<$path>, return the	1222	Delete a directory tree starting (and including) C<$path>, return the
1186	status of the final C<rmdir> only. This is a composite request that	1223	status of the final C<rmdir> only. This is a composite request that
1187	uses C<aio_scandir> to recurse into and rmdir directories, and unlink	1224	uses C<aio_scandir> to recurse into and rmdir directories, and unlink
1188	everything else.	1225	everything else.
1189		1226
1190	=cut	1227	=cut
1191		1228
…		…
1212	add $grp $dirgrp;	1249	add $grp $dirgrp;
1213	};	1250	};
1214		1251
1215	$grp	1252	$grp
1216	}	1253	}
		1254
		1255	=item aio_fcntl $fh, $cmd, $arg, $callback->($status)
		1256
		1257	=item aio_ioctl $fh, $request, $buf, $callback->($status)
		1258
		1259	These work just like the C<fcntl> and C<ioctl> built-in functions, except
		1260	they execute asynchronously and pass the return value to the callback.
		1261
		1262	Both calls can be used for a lot of things, some of which make more sense
		1263	to run asynchronously in their own thread, while some others make less
		1264	sense. For example, calls that block waiting for external events, such
		1265	as locking, will also lock down an I/O thread while it is waiting, which
		1266	can deadlock the whole I/O system. At the same time, there might be no
		1267	alternative to using a thread to wait.
		1268
		1269	So in general, you should only use these calls for things that do
		1270	(filesystem) I/O, not for things that wait for other events (network,
		1271	other processes), although if you are careful and know what you are doing,
		1272	you still can.
		1273
		1274	The following constants are available (missing ones are, as usual C<0>):
		1275
		1276	C<F_DUPFD_CLOEXEC>,
		1277
		1278	C<F_OFD_GETLK>, C<F_OFD_SETLK>, C<F_OFD_GETLKW>,
		1279
		1280	C<FIFREEZE>, C<FITHAW>, C<FITRIM>, C<FICLONE>, C<FICLONERANGE>, C<FIDEDUPERANGE>.
		1281
		1282	C<FS_IOC_GETFLAGS>, C<FS_IOC_SETFLAGS>, C<FS_IOC_GETVERSION>, C<FS_IOC_SETVERSION>,
		1283	C<FS_IOC_FIEMAP>.
		1284
		1285	C<FS_IOC_FSGETXATTR>, C<FS_IOC_FSSETXATTR>, C<FS_IOC_SET_ENCRYPTION_POLICY>,
		1286	C<FS_IOC_GET_ENCRYPTION_PWSALT>, C<FS_IOC_GET_ENCRYPTION_POLICY>, C<FS_KEY_DESCRIPTOR_SIZE>.
		1287
		1288	C<FS_SECRM_FL>, C<FS_UNRM_FL>, C<FS_COMPR_FL>, C<FS_SYNC_FL>, C<FS_IMMUTABLE_FL>,
		1289	C<FS_APPEND_FL>, C<FS_NODUMP_FL>, C<FS_NOATIME_FL>, C<FS_DIRTY_FL>,
		1290	C<FS_COMPRBLK_FL>, C<FS_NOCOMP_FL>, C<FS_ENCRYPT_FL>, C<FS_BTREE_FL>,
		1291	C<FS_INDEX_FL>, C<FS_JOURNAL_DATA_FL>, C<FS_NOTAIL_FL>, C<FS_DIRSYNC_FL>, C<FS_TOPDIR_FL>,
		1292	C<FS_FL_USER_MODIFIABLE>.
		1293
		1294	C<FS_XFLAG_REALTIME>, C<FS_XFLAG_PREALLOC>, C<FS_XFLAG_IMMUTABLE>, C<FS_XFLAG_APPEND>,
		1295	C<FS_XFLAG_SYNC>, C<FS_XFLAG_NOATIME>, C<FS_XFLAG_NODUMP>, C<FS_XFLAG_RTINHERIT>,
		1296	C<FS_XFLAG_PROJINHERIT>, C<FS_XFLAG_NOSYMLINKS>, C<FS_XFLAG_EXTSIZE>, C<FS_XFLAG_EXTSZINHERIT>,
		1297	C<FS_XFLAG_NODEFRAG>, C<FS_XFLAG_FILESTREAM>, C<FS_XFLAG_DAX>, C<FS_XFLAG_HASATTR>,
1217		1298
1218	=item aio_sync $callback->($status)	1299	=item aio_sync $callback->($status)
1219		1300
1220	Asynchronously call sync and call the callback when finished.	1301	Asynchronously call sync and call the callback when finished.
1221		1302
…		…
1290	};	1371	};
1291		1372
1292	$grp	1373	$grp
1293	}	1374	}
1294		1375
1295	=item aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	1376	=item aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status)
1296		1377
1297	This is a rather advanced IO::AIO call, which only works on mmap(2)ed	1378	This is a rather advanced IO::AIO call, which only works on mmap(2)ed
1298	scalars (see the C<IO::AIO::mmap> function, although it also works on data	1379	scalars (see the C<IO::AIO::mmap> function, although it also works on data
1299	scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the	1380	scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the
1300	scalar must only be modified in-place while an aio operation is pending on	1381	scalar must only be modified in-place while an aio operation is pending on
…		…
1302		1383
1303	It calls the C<msync> function of your OS, if available, with the memory	1384	It calls the C<msync> function of your OS, if available, with the memory
1304	area starting at C<$offset> in the string and ending C<$length> bytes	1385	area starting at C<$offset> in the string and ending C<$length> bytes
1305	later. If C<$length> is negative, counts from the end, and if C<$length>	1386	later. If C<$length> is negative, counts from the end, and if C<$length>
1306	is C<undef>, then it goes till the end of the string. The flags can be	1387	is C<undef>, then it goes till the end of the string. The flags can be
1307	a combination of C<IO::AIO::MS_ASYNC>, C<IO::AIO::MS_INVALIDATE> and	1388	either C<IO::AIO::MS_ASYNC> or C<IO::AIO::MS_SYNC>, plus an optional
1308	C<IO::AIO::MS_SYNC>.	1389	C<IO::AIO::MS_INVALIDATE>.
1309		1390
1310	=item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	1391	=item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
1311		1392
1312	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1393	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
1313	scalars.	1394	scalars.
1314		1395
1315	It touches (reads or writes) all memory pages in the specified	1396	It touches (reads or writes) all memory pages in the specified
1316	range inside the scalar. All caveats and parameters are the same	1397	range inside the scalar. All caveats and parameters are the same
1317	as for C<aio_msync>, above, except for flags, which must be either	1398	as for C<aio_msync>, above, except for flags, which must be either
1318	C<0> (which reads all pages and ensures they are instantiated) or	1399	C<0> (which reads all pages and ensures they are instantiated) or
1319	C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and	1400	C<IO::AIO::MT_MODIFY>, which modifies the memory pages (by reading and
1320	writing an octet from it, which dirties the page).	1401	writing an octet from it, which dirties the page).
1321		1402
1322	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)	1403	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
1323		1404
1324	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1405	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
…		…
1493	aio_stat [$etcdir, "passwd"], sub {	1574	aio_stat [$etcdir, "passwd"], sub {
1494	# yay	1575	# yay
1495	};	1576	};
1496	};	1577	};
1497		1578
1498	That C<aio_wd> is a request and not a normal function shows that creating	1579	The fact that C<aio_wd> is a request and not a normal function shows that
1499	an IO::AIO::WD object is itself a potentially blocking operation, which is	1580	creating an IO::AIO::WD object is itself a potentially blocking operation,
1500	why it is done asynchronously.	1581	which is why it is done asynchronously.
1501		1582
1502	To stat the directory obtained with C<aio_wd> above, one could write	1583	To stat the directory obtained with C<aio_wd> above, one could write
1503	either of the following three request calls:	1584	either of the following three request calls:
1504		1585
1505	aio_lstat "/etc" , sub { ... # pathname as normal string	1586	aio_lstat "/etc" , sub { ... # pathname as normal string
…		…
1525	will still point to the original directory. Most functions accepting a	1606	will still point to the original directory. Most functions accepting a
1526	pathname will use the directory fd on newer systems, and the string on	1607	pathname will use the directory fd on newer systems, and the string on
1527	older systems. Some functions (such as realpath) will always rely on the	1608	older systems. Some functions (such as realpath) will always rely on the
1528	string form of the pathname.	1609	string form of the pathname.
1529		1610
1530	So this fucntionality is mainly useful to get some protection against	1611	So this functionality is mainly useful to get some protection against
1531	C<chdir>, to easily get an absolute path out of a relative path for future	1612	C<chdir>, to easily get an absolute path out of a relative path for future
1532	reference, and to speed up doing many operations in the same directory	1613	reference, and to speed up doing many operations in the same directory
1533	(e.g. when stat'ing all files in a directory).	1614	(e.g. when stat'ing all files in a directory).
1534		1615
1535	The following functions implement this working directory abstraction:	1616	The following functions implement this working directory abstraction:
…		…
1548	passing C<undef> as working directory component of a pathname fails the	1629	passing C<undef> as working directory component of a pathname fails the
1549	request with C<ENOENT>, there is often no need for error checking in the	1630	request with C<ENOENT>, there is often no need for error checking in the
1550	C<aio_wd> callback, as future requests using the value will fail in the	1631	C<aio_wd> callback, as future requests using the value will fail in the
1551	expected way.	1632	expected way.
1552		1633
1553	If this call isn't available because your OS lacks it or it couldn't be
1554	detected, it will be emulated by calling C<fsync> instead.
1555
1556	=item IO::AIO::CWD	1634	=item IO::AIO::CWD
1557		1635
1558	This is a compiletime constant (object) that represents the process	1636	This is a compiletime constant (object) that represents the process
1559	current working directory.	1637	current working directory.
1560		1638
1561	Specifying this object as working directory object for a pathname is as	1639	Specifying this object as working directory object for a pathname is as if
1562	if the pathname would be specified directly, without a directory object,	1640	the pathname would be specified directly, without a directory object. For
1563	e.g., these calls are functionally identical:	1641	example, these calls are functionally identical:
1564		1642
1565	aio_stat "somefile", sub { ... };	1643	aio_stat "somefile", sub { ... };
1566	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };	1644	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };
1567		1645
1568	=back	1646	=back
1569		1647
		1648	To recover the path associated with an IO::AIO::WD object, you can use
		1649	C<aio_realpath>:
		1650
		1651	aio_realpath $wd, sub {
		1652	warn "path is $_[0]\n";
		1653	};
		1654
		1655	Currently, C<aio_statvfs> always, and C<aio_rename> and C<aio_rmdir>
		1656	sometimes, fall back to using an absolue path.
1570		1657
1571	=head2 IO::AIO::REQ CLASS	1658	=head2 IO::AIO::REQ CLASS
1572		1659
1573	All non-aggregate C<aio_*> functions return an object of this class when	1660	All non-aggregate C<aio_*> functions return an object of this class when
1574	called in non-void context.	1661	called in non-void context.
…		…
1752		1839
1753	See C<poll_cb> for an example.	1840	See C<poll_cb> for an example.
1754		1841
1755	=item IO::AIO::poll_cb	1842	=item IO::AIO::poll_cb
1756		1843
1757	Process some outstanding events on the result pipe. You have to call	1844	Process some requests that have reached the result phase (i.e. they have
		1845	been executed but the results are not yet reported). You have to call
		1846	this "regularly" to finish outstanding requests.
		1847
1758	this regularly. Returns C<0> if all events could be processed (or there	1848	Returns C<0> if all events could be processed (or there were no
1759	were no events to process), or C<-1> if it returned earlier for whatever	1849	events to process), or C<-1> if it returned earlier for whatever
1760	reason. Returns immediately when no events are outstanding. The amount of	1850	reason. Returns immediately when no events are outstanding. The amount
1761	events processed depends on the settings of C<IO::AIO::max_poll_req> and	1851	of events processed depends on the settings of C<IO::AIO::max_poll_req>,
1762	C<IO::AIO::max_poll_time>.	1852	C<IO::AIO::max_poll_time> and C<IO::AIO::max_outstanding>.
1763		1853
1764	If not all requests were processed for whatever reason, the filehandle	1854	If not all requests were processed for whatever reason, the poll file
1765	will still be ready when C<poll_cb> returns, so normally you don't have to	1855	descriptor will still be ready when C<poll_cb> returns, so normally you
1766	do anything special to have it called later.	1856	don't have to do anything special to have it called later.
1767		1857
1768	Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes	1858	Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes
1769	ready, it can be beneficial to call this function from loops which submit	1859	ready, it can be beneficial to call this function from loops which submit
1770	a lot of requests, to make sure the results get processed when they become	1860	a lot of requests, to make sure the results get processed when they become
1771	available and not just when the loop is finished and the event loop takes	1861	available and not just when the loop is finished and the event loop takes
…		…
1780	poll => 'r', async => 1,	1870	poll => 'r', async => 1,
1781	cb => \&IO::AIO::poll_cb);	1871	cb => \&IO::AIO::poll_cb);
1782		1872
1783	=item IO::AIO::poll_wait	1873	=item IO::AIO::poll_wait
1784		1874
1785	If there are any outstanding requests and none of them in the result	1875	Wait until either at least one request is in the result phase or no
1786	phase, wait till the result filehandle becomes ready for reading (simply	1876	requests are outstanding anymore.
1787	does a C<select> on the filehandle. This is useful if you want to	1877
1788	synchronously wait for some requests to finish).	1878	This is useful if you want to synchronously wait for some requests to
		1879	become ready, without actually handling them.
1789		1880
1790	See C<nreqs> for an example.	1881	See C<nreqs> for an example.
1791		1882
1792	=item IO::AIO::poll	1883	=item IO::AIO::poll
1793		1884
…		…
1914		2005
1915	This is a very bad function to use in interactive programs because it	2006	This is a very bad function to use in interactive programs because it
1916	blocks, and a bad way to reduce concurrency because it is inexact: Better	2007	blocks, and a bad way to reduce concurrency because it is inexact: Better
1917	use an C<aio_group> together with a feed callback.	2008	use an C<aio_group> together with a feed callback.
1918		2009
1919	It's main use is in scripts without an event loop - when you want to stat	2010	Its main use is in scripts without an event loop - when you want to stat
1920	a lot of files, you can write somehting like this:	2011	a lot of files, you can write somehting like this:
1921		2012
1922	IO::AIO::max_outstanding 32;	2013	IO::AIO::max_outstanding 32;
1923		2014
1924	for my $path (...) {	2015	for my $path (...) {
…		…
1964		2055
1965	=back	2056	=back
1966		2057
1967	=head3 MISCELLANEOUS FUNCTIONS	2058	=head3 MISCELLANEOUS FUNCTIONS
1968		2059
1969	IO::AIO implements some functions that might be useful, but are not	2060	IO::AIO implements some functions that are useful when you want to use
1970	asynchronous.	2061	some "Advanced I/O" function not available to in Perl, without going the
		2062	"Asynchronous I/O" route. Many of these have an asynchronous C<aio_*>
		2063	counterpart.
1971		2064
1972	=over 4	2065	=over 4
1973		2066
1974	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count	2067	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
1975		2068
…		…
1994	=item IO::AIO::madvise $scalar, $offset, $len, $advice	2087	=item IO::AIO::madvise $scalar, $offset, $len, $advice
1995		2088
1996	Simply calls the C<posix_madvise> function (see its	2089	Simply calls the C<posix_madvise> function (see its
1997	manpage for details). The following advice constants are	2090	manpage for details). The following advice constants are
1998	available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,	2091	available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,
1999	C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>.	2092	C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>,
		2093	C<IO::AIO::MADV_FREE>.
		2094
		2095	If C<$offset> is negative, counts from the end. If C<$length> is negative,
		2096	the remaining length of the C<$scalar> is used. If possible, C<$length>
		2097	will be reduced to fit into the C<$scalar>.
2000		2098
2001	On systems that do not implement C<posix_madvise>, this function returns	2099	On systems that do not implement C<posix_madvise>, this function returns
2002	ENOSYS, otherwise the return value of C<posix_madvise>.	2100	ENOSYS, otherwise the return value of C<posix_madvise>.
2003		2101
2004	=item IO::AIO::mprotect $scalar, $offset, $len, $protect	2102	=item IO::AIO::mprotect $scalar, $offset, $len, $protect
…		…
2006	Simply calls the C<mprotect> function on the preferably AIO::mmap'ed	2104	Simply calls the C<mprotect> function on the preferably AIO::mmap'ed
2007	$scalar (see its manpage for details). The following protect	2105	$scalar (see its manpage for details). The following protect
2008	constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,	2106	constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,
2009	C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.	2107	C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.
2010		2108
		2109	If C<$offset> is negative, counts from the end. If C<$length> is negative,
		2110	the remaining length of the C<$scalar> is used. If possible, C<$length>
		2111	will be reduced to fit into the C<$scalar>.
		2112
2011	On systems that do not implement C<mprotect>, this function returns	2113	On systems that do not implement C<mprotect>, this function returns
2012	ENOSYS, otherwise the return value of C<mprotect>.	2114	ENOSYS, otherwise the return value of C<mprotect>.
2013		2115
2014	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]	2116	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]
2015		2117
2016	Memory-maps a file (or anonymous memory range) and attaches it to the	2118	Memory-maps a file (or anonymous memory range) and attaches it to the
2017	given C<$scalar>, which will act like a string scalar. Returns true on	2119	given C<$scalar>, which will act like a string scalar. Returns true on
2018	success, and false otherwise.	2120	success, and false otherwise.
2019		2121
		2122	The scalar must exist, but its contents do not matter - this means you
		2123	cannot use a nonexistant array or hash element. When in doubt, C<undef>
		2124	the scalar first.
		2125
2020	The only operations allowed on the scalar are C<substr>/C<vec> that don't	2126	The only operations allowed on the mmapped scalar are C<substr>/C<vec>,
2021	change the string length, and most read-only operations such as copying it	2127	which don't change the string length, and most read-only operations such
2022	or searching it with regexes and so on.	2128	as copying it or searching it with regexes and so on.
2023		2129
2024	Anything else is unsafe and will, at best, result in memory leaks.	2130	Anything else is unsafe and will, at best, result in memory leaks.
2025		2131
2026	The memory map associated with the C<$scalar> is automatically removed	2132	The memory map associated with the C<$scalar> is automatically removed
2027	when the C<$scalar> is destroyed, or when the C<IO::AIO::mmap> or	2133	when the C<$scalar> is undef'd or destroyed, or when the C<IO::AIO::mmap>
2028	C<IO::AIO::munmap> functions are called.	2134	or C<IO::AIO::munmap> functions are called on it.
2029		2135
2030	This calls the C<mmap>(2) function internally. See your system's manual	2136	This calls the C<mmap>(2) function internally. See your system's manual
2031	page for details on the C<$length>, C<$prot> and C<$flags> parameters.	2137	page for details on the C<$length>, C<$prot> and C<$flags> parameters.
2032		2138
2033	The C<$length> must be larger than zero and smaller than the actual	2139	The C<$length> must be larger than zero and smaller than the actual
2034	filesize.	2140	filesize.
2035		2141
2036	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,	2142	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,
2037	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,	2143	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,
2038		2144
2039	C<$flags> can be a combination of C<IO::AIO::MAP_SHARED> or	2145	C<$flags> can be a combination of
2040	C<IO::AIO::MAP_PRIVATE>, or a number of system-specific flags (when	2146	C<IO::AIO::MAP_SHARED> or
2041	not available, the are defined as 0): C<IO::AIO::MAP_ANONYMOUS>	2147	C<IO::AIO::MAP_PRIVATE>,
		2148	or a number of system-specific flags (when not available, the are C<0>):
2042	(which is set to C<MAP_ANON> if your system only provides this	2149	C<IO::AIO::MAP_ANONYMOUS> (which is set to C<MAP_ANON> if your system only provides this constant),
2043	constant), C<IO::AIO::MAP_HUGETLB>, C<IO::AIO::MAP_LOCKED>,	2150	C<IO::AIO::MAP_LOCKED>,
2044	C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or	2151	C<IO::AIO::MAP_NORESERVE>,
		2152	C<IO::AIO::MAP_POPULATE>,
2045	C<IO::AIO::MAP_NONBLOCK>	2153	C<IO::AIO::MAP_NONBLOCK>,
		2154	C<IO::AIO::MAP_FIXED>,
		2155	C<IO::AIO::MAP_GROWSDOWN>,
		2156	C<IO::AIO::MAP_32BIT>,
		2157	C<IO::AIO::MAP_HUGETLB> or
		2158	C<IO::AIO::MAP_STACK>.
2046		2159
2047	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.	2160	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.
2048		2161
2049	C<$offset> is the offset from the start of the file - it generally must be	2162	C<$offset> is the offset from the start of the file - it generally must be
2050	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.	2163	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.
…		…
2093		2206
2094	See the C<splice(2)> manpage for details.	2207	See the C<splice(2)> manpage for details.
2095		2208
2096	=item IO::AIO::tee $r_fh, $w_fh, $length, $flags	2209	=item IO::AIO::tee $r_fh, $w_fh, $length, $flags
2097		2210
2098	Calls the GNU/Linux C<tee(2)> syscall, see it's manpage and the	2211	Calls the GNU/Linux C<tee(2)> syscall, see its manpage and the
2099	description for C<IO::AIO::splice> above for details.	2212	description for C<IO::AIO::splice> above for details.
		2213
		2214	=item $actual_size = IO::AIO::pipesize $r_fh[, $new_size]
		2215
		2216	Attempts to query or change the pipe buffer size. Obviously works only
		2217	on pipes, and currently works only on GNU/Linux systems, and fails with
		2218	C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer
		2219	size on other systems, drop me a note.
		2220
		2221	=item ($rfh, $wfh) = IO::AIO::pipe2 [$flags]
		2222
		2223	This is a direct interface to the Linux L<pipe2(2)> system call. If
		2224	C<$flags> is missing or C<0>, then this should be the same as a call to
		2225	perl's built-in C<pipe> function and create a new pipe, and works on
		2226	systems that lack the pipe2 syscall. On win32, this case invokes C<_pipe
		2227	(..., 4096, O_BINARY)>.
		2228
		2229	If C<$flags> is non-zero, it tries to invoke the pipe2 system call with
		2230	the given flags (Linux 2.6.27, glibc 2.9).
		2231
		2232	On success, the read and write file handles are returned.
		2233
		2234	On error, nothing will be returned. If the pipe2 syscall is missing and
		2235	C<$flags> is non-zero, fails with C<ENOSYS>.
		2236
		2237	Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the
		2238	time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and
		2239	C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported.
2100		2240
2101	=back	2241	=back
2102		2242
2103	=cut	2243	=cut
2104		2244

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Comparing IO-AIO/AIO.pm (file contents): Revision 1.238 by root, Thu Oct 11 05:01:56 2012 UTC vs. Revision 1.271 by root, Fri Jun 23 21:43:51 2017 UTC

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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.238 by root, Thu Oct 11 05:01:56 2012 UTC vs.
Revision 1.271 by root, Fri Jun 23 21:43:51 2017 UTC