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

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.235 by root, Wed Aug 22 22:28:03 2012 UTC vs.
Revision 1.276 by root, Fri Sep 22 05:24:41 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 = '4.16';	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_fallocate	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->()
…		…
271	IO::AIO::idle_timeout $seconds	277	IO::AIO::idle_timeout $seconds
272	IO::AIO::max_outstanding $maxreqs	278	IO::AIO::max_outstanding $maxreqs
273	IO::AIO::nreqs	279	IO::AIO::nreqs
274	IO::AIO::nready	280	IO::AIO::nready
275	IO::AIO::npending	281	IO::AIO::npending
		282	IO::AIO::min_fdlimit $nfd;
276		283
277	IO::AIO::sendfile $ofh, $ifh, $offset, $count	284	IO::AIO::sendfile $ofh, $ifh, $offset, $count
278	IO::AIO::fadvise $fh, $offset, $len, $advice	285	IO::AIO::fadvise $fh, $offset, $len, $advice
279	IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]]	286	IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]]
280	IO::AIO::munmap $scalar	287	IO::AIO::munmap $scalar
…		…
395	following POSIX and non-POSIX constants are available (missing ones on	402	following POSIX and non-POSIX constants are available (missing ones on
396	your system are, as usual, C<0>):	403	your system are, as usual, C<0>):
397		404
398	C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,	405	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>,	406	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>.	407	C<O_RSYNC>, C<O_SYNC>, C<O_PATH>, C<O_TMPFILE>, and C<O_TTY_INIT>.
401		408
402		409
403	=item aio_close $fh, $callback->($status)	410	=item aio_close $fh, $callback->($status)
404		411
405	Asynchronously close a file and call the callback with the result	412	Asynchronously close a file and call the callback with the result
…		…
440	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	447	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
441		448
442	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	449	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
443		450
444	Reads or writes C<$length> bytes from or to the specified C<$fh> and	451	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<$dataoffset>	452	C<$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	453	calls the callback with the actual number of bytes transferred (or -1 on
447	error, just like the syscall).	454	error, just like the syscall).
448		455
449	C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to	456	C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to
450	offset plus the actual number of bytes read.	457	offset plus the actual number of bytes read.
451		458
…		…
509	As native sendfile syscalls (as practically any non-POSIX interface hacked	516	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	517	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	518	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,	519	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> -	520	so you really really should check the return value of C<aio_sendfile> -
514	fewre bytes than expected might have been transferred.	521	fewer bytes than expected might have been transferred.
515		522
516		523
517	=item aio_readahead $fh,$offset,$length, $callback->($retval)	524	=item aio_readahead $fh,$offset,$length, $callback->($retval)
518		525
519	C<aio_readahead> populates the page cache with data from a file so that	526	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	530	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	531	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	532	(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.	533	file. The current file offset of the file is left unchanged.
527		534
528	If that syscall doesn't exist (likely if your OS isn't Linux) it will be	535	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.	536	be emulated by simply reading the data, which would have a similar effect.
530		537
531		538
532	=item aio_stat $fh_or_path, $callback->($status)	539	=item aio_stat $fh_or_path, $callback->($status)
533		540
534	=item aio_lstat $fh, $callback->($status)	541	=item aio_lstat $fh, $callback->($status)
…		…
603	namemax => 255,	610	namemax => 255,
604	frsize => 1024,	611	frsize => 1024,
605	fsid => 1810	612	fsid => 1810
606	}	613	}
607		614
608	Here is a (likely partial) list of fsid values used by Linux - it is safe	615	Here is a (likely partial - send me updates!) list of fsid values used by
609	to hardcode these when the $^O is C<linux>:	616	Linux - it is safe to hardcode these when C<$^O> is C<linux>:
610		617
611	0x0000adf5 adfs	618	0x0000adf5 adfs
612	0x0000adff affs	619	0x0000adff affs
613	0x5346414f afs	620	0x5346414f afs
614	0x09041934 anon-inode filesystem	621	0x09041934 anon-inode filesystem
…		…
627	0x00001373 devfs	634	0x00001373 devfs
628	0x00001cd1 devpts	635	0x00001cd1 devpts
629	0x0000f15f ecryptfs	636	0x0000f15f ecryptfs
630	0x00414a53 efs	637	0x00414a53 efs
631	0x0000137d ext	638	0x0000137d ext
632	0x0000ef53 ext2/ext3	639	0x0000ef53 ext2/ext3/ext4
633	0x0000ef51 ext2	640	0x0000ef51 ext2
		641	0xf2f52010 f2fs
634	0x00004006 fat	642	0x00004006 fat
635	0x65735546 fuseblk	643	0x65735546 fuseblk
636	0x65735543 fusectl	644	0x65735543 fusectl
637	0x0bad1dea futexfs	645	0x0bad1dea futexfs
638	0x01161970 gfs2	646	0x01161970 gfs2
639	0x47504653 gpfs	647	0x47504653 gpfs
640	0x00004244 hfs	648	0x00004244 hfs
641	0xf995e849 hpfs	649	0xf995e849 hpfs
		650	0x00c0ffee hostfs
642	0x958458f6 hugetlbfs	651	0x958458f6 hugetlbfs
643	0x2bad1dea inotifyfs	652	0x2bad1dea inotifyfs
644	0x00009660 isofs	653	0x00009660 isofs
645	0x000072b6 jffs2	654	0x000072b6 jffs2
646	0x3153464a jfs	655	0x3153464a jfs
…		…
661	0x00009fa1 openprom	670	0x00009fa1 openprom
662	0x7461636F ocfs2	671	0x7461636F ocfs2
663	0x00009fa0 proc	672	0x00009fa0 proc
664	0x6165676c pstorefs	673	0x6165676c pstorefs
665	0x0000002f qnx4	674	0x0000002f qnx4
		675	0x68191122 qnx6
666	0x858458f6 ramfs	676	0x858458f6 ramfs
667	0x52654973 reiserfs	677	0x52654973 reiserfs
668	0x00007275 romfs	678	0x00007275 romfs
669	0x67596969 rpc_pipefs	679	0x67596969 rpc_pipefs
670	0x73636673 securityfs	680	0x73636673 securityfs
…		…
723	Works like truncate(2) or ftruncate(2).	733	Works like truncate(2) or ftruncate(2).
724		734
725		735
726	=item aio_allocate $fh, $mode, $offset, $len, $callback->($status)	736	=item aio_allocate $fh, $mode, $offset, $len, $callback->($status)
727		737
728	Allocates or freed disk space according to the C<$mode> argument. See the	738	Allocates or frees disk space according to the C<$mode> argument. See the
729	linux C<fallocate> docuemntation for details.	739	linux C<fallocate> documentation for details.
730		740
731	C<$mode> can currently be C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE>	741	C<$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 \|	742	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.	743	to deallocate a file range.
		744
		745	IO::AIO also supports C<FALLOC_FL_COLLAPSE_RANGE>, to remove a range
		746	(without leaving a hole), C<FALLOC_FL_ZERO_RANGE>, to zero a range,
		747	C<FALLOC_FL_INSERT_RANGE> to insert a range and C<FALLOC_FL_UNSHARE_RANGE>
		748	to unshare shared blocks (see your L<fallocate(2)> manpage).
734		749
735	The file system block size used by C<fallocate> is presumably the	750	The file system block size used by C<fallocate> is presumably the
736	C<f_bsize> returned by C<statvfs>.	751	C<f_bsize> returned by C<statvfs>, but different filesystems and filetypes
		752	can dictate other limitations.
737		753
738	If C<fallocate> isn't available or cannot be emulated (currently no	754	If C<fallocate> isn't available or cannot be emulated (currently no
739	emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>.	755	emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>.
740		756
741		757
…		…
783		799
784		800
785	=item aio_realpath $pathname, $callback->($path)	801	=item aio_realpath $pathname, $callback->($path)
786		802
787	Asynchronously make the path absolute and resolve any symlinks in	803	Asynchronously make the path absolute and resolve any symlinks in
788	C<$path>. The resulting path only consists of directories (Same as	804	C<$path>. The resulting path only consists of directories (same as
789	L<Cwd::realpath>).	805	L<Cwd::realpath>).
790		806
791	This request can be used to get the absolute path of the current working	807	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).	808	directory by passing it a path of F<.> (a single dot).
793		809
794		810
795	=item aio_rename $srcpath, $dstpath, $callback->($status)	811	=item aio_rename $srcpath, $dstpath, $callback->($status)
796		812
797	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as	813	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as
798	rename(2) and call the callback with the result code.	814	rename(2) and call the callback with the result code.
		815
		816	On systems that support the AIO::WD working directory abstraction
		817	natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead
		818	of failing, C<rename> is called on the absolute path of C<$wd>.
		819
		820
		821	=item aio_rename2 $srcpath, $dstpath, $flags, $callback->($status)
		822
		823	Basically a version of C<aio_rename> with an additional C<$flags>
		824	argument. Calling this with C<$flags=0> is the same as calling
		825	C<aio_rename>.
		826
		827	Non-zero flags are currently only supported on GNU/Linux systems that
		828	support renameat2. Other systems fail with C<ENOSYS> in this case.
		829
		830	The following constants are available (missing ones are, as usual C<0>),
		831	see renameat2(2) for details:
		832
		833	C<IO::AIO::RENAME_NOREPLACE>, C<IO::AIO::RENAME_EXCHANGE>
		834	and C<IO::AIO::RENAME_WHITEOUT>.
799		835
800		836
801	=item aio_mkdir $pathname, $mode, $callback->($status)	837	=item aio_mkdir $pathname, $mode, $callback->($status)
802		838
803	Asynchronously mkdir (create) a directory and call the callback with	839	Asynchronously mkdir (create) a directory and call the callback with
…		…
807		843
808	=item aio_rmdir $pathname, $callback->($status)	844	=item aio_rmdir $pathname, $callback->($status)
809		845
810	Asynchronously rmdir (delete) a directory and call the callback with the	846	Asynchronously rmdir (delete) a directory and call the callback with the
811	result code.	847	result code.
		848
		849	On systems that support the AIO::WD working directory abstraction
		850	natively, the case C<[$wd, "."]> is specialcased - instead of failing,
		851	C<rmdir> is called on the absolute path of C<$wd>.
812		852
813		853
814	=item aio_readdir $pathname, $callback->($entries)	854	=item aio_readdir $pathname, $callback->($entries)
815		855
816	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire	856	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire
…		…
918	=item aio_copy $srcpath, $dstpath, $callback->($status)	958	=item aio_copy $srcpath, $dstpath, $callback->($status)
919		959
920	Try to copy the I<file> (directories not supported as either source or	960	Try to copy the I<file> (directories not supported as either source or
921	destination) from C<$srcpath> to C<$dstpath> and call the callback with	961	destination) from C<$srcpath> to C<$dstpath> and call the callback with
922	a status of C<0> (ok) or C<-1> (error, see C<$!>).	962	a status of C<0> (ok) or C<-1> (error, see C<$!>).
		963
		964	Existing destination files will be truncated.
923		965
924	This is a composite request that creates the destination file with	966	This is a composite request that creates the destination file with
925	mode 0200 and copies the contents of the source file into it using	967	mode 0200 and copies the contents of the source file into it using
926	C<aio_sendfile>, followed by restoring atime, mtime, access mode and	968	C<aio_sendfile>, followed by restoring atime, mtime, access mode and
927	uid/gid, in that order.	969	uid/gid, in that order.
…		…
1181	}	1223	}
1182		1224
1183	=item aio_rmtree $pathname, $callback->($status)	1225	=item aio_rmtree $pathname, $callback->($status)
1184		1226
1185	Delete a directory tree starting (and including) C<$path>, return the	1227	Delete a directory tree starting (and including) C<$path>, return the
1186	status of the final C<rmdir> only. This is a composite request that	1228	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	1229	uses C<aio_scandir> to recurse into and rmdir directories, and unlink
1188	everything else.	1230	everything else.
1189		1231
1190	=cut	1232	=cut
1191		1233
…		…
1212	add $grp $dirgrp;	1254	add $grp $dirgrp;
1213	};	1255	};
1214		1256
1215	$grp	1257	$grp
1216	}	1258	}
		1259
		1260	=item aio_fcntl $fh, $cmd, $arg, $callback->($status)
		1261
		1262	=item aio_ioctl $fh, $request, $buf, $callback->($status)
		1263
		1264	These work just like the C<fcntl> and C<ioctl> built-in functions, except
		1265	they execute asynchronously and pass the return value to the callback.
		1266
		1267	Both calls can be used for a lot of things, some of which make more sense
		1268	to run asynchronously in their own thread, while some others make less
		1269	sense. For example, calls that block waiting for external events, such
		1270	as locking, will also lock down an I/O thread while it is waiting, which
		1271	can deadlock the whole I/O system. At the same time, there might be no
		1272	alternative to using a thread to wait.
		1273
		1274	So in general, you should only use these calls for things that do
		1275	(filesystem) I/O, not for things that wait for other events (network,
		1276	other processes), although if you are careful and know what you are doing,
		1277	you still can.
		1278
		1279	The following constants are available (missing ones are, as usual C<0>):
		1280
		1281	C<F_DUPFD_CLOEXEC>,
		1282
		1283	C<F_OFD_GETLK>, C<F_OFD_SETLK>, C<F_OFD_GETLKW>,
		1284
		1285	C<FIFREEZE>, C<FITHAW>, C<FITRIM>, C<FICLONE>, C<FICLONERANGE>, C<FIDEDUPERANGE>.
		1286
		1287	C<FS_IOC_GETFLAGS>, C<FS_IOC_SETFLAGS>, C<FS_IOC_GETVERSION>, C<FS_IOC_SETVERSION>,
		1288	C<FS_IOC_FIEMAP>.
		1289
		1290	C<FS_IOC_FSGETXATTR>, C<FS_IOC_FSSETXATTR>, C<FS_IOC_SET_ENCRYPTION_POLICY>,
		1291	C<FS_IOC_GET_ENCRYPTION_PWSALT>, C<FS_IOC_GET_ENCRYPTION_POLICY>, C<FS_KEY_DESCRIPTOR_SIZE>.
		1292
		1293	C<FS_SECRM_FL>, C<FS_UNRM_FL>, C<FS_COMPR_FL>, C<FS_SYNC_FL>, C<FS_IMMUTABLE_FL>,
		1294	C<FS_APPEND_FL>, C<FS_NODUMP_FL>, C<FS_NOATIME_FL>, C<FS_DIRTY_FL>,
		1295	C<FS_COMPRBLK_FL>, C<FS_NOCOMP_FL>, C<FS_ENCRYPT_FL>, C<FS_BTREE_FL>,
		1296	C<FS_INDEX_FL>, C<FS_JOURNAL_DATA_FL>, C<FS_NOTAIL_FL>, C<FS_DIRSYNC_FL>, C<FS_TOPDIR_FL>,
		1297	C<FS_FL_USER_MODIFIABLE>.
		1298
		1299	C<FS_XFLAG_REALTIME>, C<FS_XFLAG_PREALLOC>, C<FS_XFLAG_IMMUTABLE>, C<FS_XFLAG_APPEND>,
		1300	C<FS_XFLAG_SYNC>, C<FS_XFLAG_NOATIME>, C<FS_XFLAG_NODUMP>, C<FS_XFLAG_RTINHERIT>,
		1301	C<FS_XFLAG_PROJINHERIT>, C<FS_XFLAG_NOSYMLINKS>, C<FS_XFLAG_EXTSIZE>, C<FS_XFLAG_EXTSZINHERIT>,
		1302	C<FS_XFLAG_NODEFRAG>, C<FS_XFLAG_FILESTREAM>, C<FS_XFLAG_DAX>, C<FS_XFLAG_HASATTR>,
1217		1303
1218	=item aio_sync $callback->($status)	1304	=item aio_sync $callback->($status)
1219		1305
1220	Asynchronously call sync and call the callback when finished.	1306	Asynchronously call sync and call the callback when finished.
1221		1307
…		…
1290	};	1376	};
1291		1377
1292	$grp	1378	$grp
1293	}	1379	}
1294		1380
1295	=item aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	1381	=item aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status)
1296		1382
1297	This is a rather advanced IO::AIO call, which only works on mmap(2)ed	1383	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	1384	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	1385	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	1386	scalar must only be modified in-place while an aio operation is pending on
…		…
1302		1388
1303	It calls the C<msync> function of your OS, if available, with the memory	1389	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	1390	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>	1391	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	1392	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	1393	either C<IO::AIO::MS_ASYNC> or C<IO::AIO::MS_SYNC>, plus an optional
1308	C<IO::AIO::MS_SYNC>.	1394	C<IO::AIO::MS_INVALIDATE>.
1309		1395
1310	=item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	1396	=item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
1311		1397
1312	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1398	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
1313	scalars.	1399	scalars.
1314		1400
1315	It touches (reads or writes) all memory pages in the specified	1401	It touches (reads or writes) all memory pages in the specified
1316	range inside the scalar. All caveats and parameters are the same	1402	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	1403	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	1404	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	1405	C<IO::AIO::MT_MODIFY>, which modifies the memory pages (by reading and
1320	writing an octet from it, which dirties the page).	1406	writing an octet from it, which dirties the page).
1321		1407
1322	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)	1408	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
1323		1409
1324	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1410	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
…		…
1493	aio_stat [$etcdir, "passwd"], sub {	1579	aio_stat [$etcdir, "passwd"], sub {
1494	# yay	1580	# yay
1495	};	1581	};
1496	};	1582	};
1497		1583
1498	That C<aio_wd> is a request and not a normal function shows that creating	1584	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	1585	creating an IO::AIO::WD object is itself a potentially blocking operation,
1500	why it is done asynchronously.	1586	which is why it is done asynchronously.
1501		1587
1502	To stat the directory obtained with C<aio_wd> above, one could write	1588	To stat the directory obtained with C<aio_wd> above, one could write
1503	either of the following three request calls:	1589	either of the following three request calls:
1504		1590
1505	aio_lstat "/etc" , sub { ... # pathname as normal string	1591	aio_lstat "/etc" , sub { ... # pathname as normal string
…		…
1525	will still point to the original directory. Most functions accepting a	1611	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	1612	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	1613	older systems. Some functions (such as realpath) will always rely on the
1528	string form of the pathname.	1614	string form of the pathname.
1529		1615
1530	So this fucntionality is mainly useful to get some protection against	1616	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	1617	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	1618	reference, and to speed up doing many operations in the same directory
1533	(e.g. when stat'ing all files in a directory).	1619	(e.g. when stat'ing all files in a directory).
1534		1620
1535	The following functions implement this working directory abstraction:	1621	The following functions implement this working directory abstraction:
…		…
1548	passing C<undef> as working directory component of a pathname fails the	1634	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	1635	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	1636	C<aio_wd> callback, as future requests using the value will fail in the
1551	expected way.	1637	expected way.
1552		1638
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	1639	=item IO::AIO::CWD
1557		1640
1558	This is a compiletime constant (object) that represents the process	1641	This is a compiletime constant (object) that represents the process
1559	current working directory.	1642	current working directory.
1560		1643
1561	Specifying this object as working directory object for a pathname is as	1644	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,	1645	the pathname would be specified directly, without a directory object. For
1563	e.g., these calls are functionally identical:	1646	example, these calls are functionally identical:
1564		1647
1565	aio_stat "somefile", sub { ... };	1648	aio_stat "somefile", sub { ... };
1566	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };	1649	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };
1567		1650
1568	=back	1651	=back
1569		1652
		1653	To recover the path associated with an IO::AIO::WD object, you can use
		1654	C<aio_realpath>:
		1655
		1656	aio_realpath $wd, sub {
		1657	warn "path is $_[0]\n";
		1658	};
		1659
		1660	Currently, C<aio_statvfs> always, and C<aio_rename> and C<aio_rmdir>
		1661	sometimes, fall back to using an absolue path.
1570		1662
1571	=head2 IO::AIO::REQ CLASS	1663	=head2 IO::AIO::REQ CLASS
1572		1664
1573	All non-aggregate C<aio_*> functions return an object of this class when	1665	All non-aggregate C<aio_*> functions return an object of this class when
1574	called in non-void context.	1666	called in non-void context.
…		…
1752		1844
1753	See C<poll_cb> for an example.	1845	See C<poll_cb> for an example.
1754		1846
1755	=item IO::AIO::poll_cb	1847	=item IO::AIO::poll_cb
1756		1848
1757	Process some outstanding events on the result pipe. You have to call	1849	Process some requests that have reached the result phase (i.e. they have
		1850	been executed but the results are not yet reported). You have to call
		1851	this "regularly" to finish outstanding requests.
		1852
1758	this regularly. Returns C<0> if all events could be processed (or there	1853	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	1854	events to process), or C<-1> if it returned earlier for whatever
1760	reason. Returns immediately when no events are outstanding. The amount of	1855	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	1856	of events processed depends on the settings of C<IO::AIO::max_poll_req>,
1762	C<IO::AIO::max_poll_time>.	1857	C<IO::AIO::max_poll_time> and C<IO::AIO::max_outstanding>.
1763		1858
1764	If not all requests were processed for whatever reason, the filehandle	1859	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	1860	descriptor will still be ready when C<poll_cb> returns, so normally you
1766	do anything special to have it called later.	1861	don't have to do anything special to have it called later.
1767		1862
1768	Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes	1863	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	1864	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	1865	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	1866	available and not just when the loop is finished and the event loop takes
…		…
1780	poll => 'r', async => 1,	1875	poll => 'r', async => 1,
1781	cb => \&IO::AIO::poll_cb);	1876	cb => \&IO::AIO::poll_cb);
1782		1877
1783	=item IO::AIO::poll_wait	1878	=item IO::AIO::poll_wait
1784		1879
1785	If there are any outstanding requests and none of them in the result	1880	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	1881	requests are outstanding anymore.
1787	does a C<select> on the filehandle. This is useful if you want to	1882
1788	synchronously wait for some requests to finish).	1883	This is useful if you want to synchronously wait for some requests to
		1884	become ready, without actually handling them.
1789		1885
1790	See C<nreqs> for an example.	1886	See C<nreqs> for an example.
1791		1887
1792	=item IO::AIO::poll	1888	=item IO::AIO::poll
1793		1889
…		…
1914		2010
1915	This is a very bad function to use in interactive programs because it	2011	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	2012	blocks, and a bad way to reduce concurrency because it is inexact: Better
1917	use an C<aio_group> together with a feed callback.	2013	use an C<aio_group> together with a feed callback.
1918		2014
1919	It's main use is in scripts without an event loop - when you want to stat	2015	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:	2016	a lot of files, you can write something like this:
1921		2017
1922	IO::AIO::max_outstanding 32;	2018	IO::AIO::max_outstanding 32;
1923		2019
1924	for my $path (...) {	2020	for my $path (...) {
1925	aio_stat $path , ...;	2021	aio_stat $path , ...;
…		…
1964		2060
1965	=back	2061	=back
1966		2062
1967	=head3 MISCELLANEOUS FUNCTIONS	2063	=head3 MISCELLANEOUS FUNCTIONS
1968		2064
1969	IO::AIO implements some functions that might be useful, but are not	2065	IO::AIO implements some functions that are useful when you want to use
1970	asynchronous.	2066	some "Advanced I/O" function not available to in Perl, without going the
		2067	"Asynchronous I/O" route. Many of these have an asynchronous C<aio_*>
		2068	counterpart.
1971		2069
1972	=over 4	2070	=over 4
		2071
		2072	=item $numfd = IO::AIO::get_fdlimit
		2073
		2074	Tries to find the current file descriptor limit and returns it, or
		2075	C<undef> and sets C<$!> in case of an error. The limit is one larger than
		2076	the highest valid file descriptor number.
		2077
		2078	=item IO::AIO::min_fdlimit [$numfd]
		2079
		2080	Try to increase the current file descriptor limit(s) to at least C<$numfd>
		2081	by changing the soft or hard file descriptor resource limit. If C<$numfd>
		2082	is missing, it will try to set a very high limit, although this is not
		2083	recommended when you know the actual minimum that you require.
		2084
		2085	If the limit cannot be raised enough, the function makes a best-effort
		2086	attempt to increase the limit as much as possible, using various
		2087	tricks, while still failing. You can query the resulting limit using
		2088	C<IO::AIO::get_fdlimit>.
		2089
		2090	If an error occurs, returns C<undef> and sets C<$!>, otherwise returns
		2091	true.
1973		2092
1974	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count	2093	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
1975		2094
1976	Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>,	2095	Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>,
1977	but is blocking (this makes most sense if you know the input data is	2096	but is blocking (this makes most sense if you know the input data is
…		…
1994	=item IO::AIO::madvise $scalar, $offset, $len, $advice	2113	=item IO::AIO::madvise $scalar, $offset, $len, $advice
1995		2114
1996	Simply calls the C<posix_madvise> function (see its	2115	Simply calls the C<posix_madvise> function (see its
1997	manpage for details). The following advice constants are	2116	manpage for details). The following advice constants are
1998	available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,	2117	available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,
1999	C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>.	2118	C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>,
		2119	C<IO::AIO::MADV_DONTNEED>.
		2120
		2121	If C<$offset> is negative, counts from the end. If C<$length> is negative,
		2122	the remaining length of the C<$scalar> is used. If possible, C<$length>
		2123	will be reduced to fit into the C<$scalar>.
2000		2124
2001	On systems that do not implement C<posix_madvise>, this function returns	2125	On systems that do not implement C<posix_madvise>, this function returns
2002	ENOSYS, otherwise the return value of C<posix_madvise>.	2126	ENOSYS, otherwise the return value of C<posix_madvise>.
2003		2127
2004	=item IO::AIO::mprotect $scalar, $offset, $len, $protect	2128	=item IO::AIO::mprotect $scalar, $offset, $len, $protect
…		…
2006	Simply calls the C<mprotect> function on the preferably AIO::mmap'ed	2130	Simply calls the C<mprotect> function on the preferably AIO::mmap'ed
2007	$scalar (see its manpage for details). The following protect	2131	$scalar (see its manpage for details). The following protect
2008	constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,	2132	constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,
2009	C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.	2133	C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.
2010		2134
		2135	If C<$offset> is negative, counts from the end. If C<$length> is negative,
		2136	the remaining length of the C<$scalar> is used. If possible, C<$length>
		2137	will be reduced to fit into the C<$scalar>.
		2138
2011	On systems that do not implement C<mprotect>, this function returns	2139	On systems that do not implement C<mprotect>, this function returns
2012	ENOSYS, otherwise the return value of C<mprotect>.	2140	ENOSYS, otherwise the return value of C<mprotect>.
2013		2141
2014	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]	2142	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]
2015		2143
2016	Memory-maps a file (or anonymous memory range) and attaches it to the	2144	Memory-maps a file (or anonymous memory range) and attaches it to the
2017	given C<$scalar>, which will act like a string scalar. Returns true on	2145	given C<$scalar>, which will act like a string scalar. Returns true on
2018	success, and false otherwise.	2146	success, and false otherwise.
2019		2147
		2148	The scalar must exist, but its contents do not matter - this means you
		2149	cannot use a nonexistant array or hash element. When in doubt, C<undef>
		2150	the scalar first.
		2151
2020	The only operations allowed on the scalar are C<substr>/C<vec> that don't	2152	The only operations allowed on the mmapped scalar are C<substr>/C<vec>,
2021	change the string length, and most read-only operations such as copying it	2153	which don't change the string length, and most read-only operations such
2022	or searching it with regexes and so on.	2154	as copying it or searching it with regexes and so on.
2023		2155
2024	Anything else is unsafe and will, at best, result in memory leaks.	2156	Anything else is unsafe and will, at best, result in memory leaks.
2025		2157
2026	The memory map associated with the C<$scalar> is automatically removed	2158	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	2159	when the C<$scalar> is undef'd or destroyed, or when the C<IO::AIO::mmap>
2028	C<IO::AIO::munmap> functions are called.	2160	or C<IO::AIO::munmap> functions are called on it.
2029		2161
2030	This calls the C<mmap>(2) function internally. See your system's manual	2162	This calls the C<mmap>(2) function internally. See your system's manual
2031	page for details on the C<$length>, C<$prot> and C<$flags> parameters.	2163	page for details on the C<$length>, C<$prot> and C<$flags> parameters.
2032		2164
2033	The C<$length> must be larger than zero and smaller than the actual	2165	The C<$length> must be larger than zero and smaller than the actual
2034	filesize.	2166	filesize.
2035		2167
2036	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,	2168	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,
2037	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,	2169	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,
2038		2170
2039	C<$flags> can be a combination of C<IO::AIO::MAP_SHARED> or	2171	C<$flags> can be a combination of
2040	C<IO::AIO::MAP_PRIVATE>, or a number of system-specific flags (when	2172	C<IO::AIO::MAP_SHARED> or
2041	not available, the are defined as 0): C<IO::AIO::MAP_ANONYMOUS>	2173	C<IO::AIO::MAP_PRIVATE>,
		2174	or a number of system-specific flags (when not available, the are C<0>):
2042	(which is set to C<MAP_ANON> if your system only provides this	2175	C<IO::AIO::MAP_ANONYMOUS> (which is set to C<MAP_ANON> if your system only provides this constant),
2043	constant), C<IO::AIO::MAP_HUGETLB>, C<IO::AIO::MAP_LOCKED>,	2176	C<IO::AIO::MAP_LOCKED>,
2044	C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or	2177	C<IO::AIO::MAP_NORESERVE>,
		2178	C<IO::AIO::MAP_POPULATE>,
2045	C<IO::AIO::MAP_NONBLOCK>	2179	C<IO::AIO::MAP_NONBLOCK>,
		2180	C<IO::AIO::MAP_FIXED>,
		2181	C<IO::AIO::MAP_GROWSDOWN>,
		2182	C<IO::AIO::MAP_32BIT>,
		2183	C<IO::AIO::MAP_HUGETLB> or
		2184	C<IO::AIO::MAP_STACK>.
2046		2185
2047	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.	2186	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.
2048		2187
2049	C<$offset> is the offset from the start of the file - it generally must be	2188	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>.	2189	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.
…		…
2093		2232
2094	See the C<splice(2)> manpage for details.	2233	See the C<splice(2)> manpage for details.
2095		2234
2096	=item IO::AIO::tee $r_fh, $w_fh, $length, $flags	2235	=item IO::AIO::tee $r_fh, $w_fh, $length, $flags
2097		2236
2098	Calls the GNU/Linux C<tee(2)> syscall, see it's manpage and the	2237	Calls the GNU/Linux C<tee(2)> syscall, see its manpage and the
2099	description for C<IO::AIO::splice> above for details.	2238	description for C<IO::AIO::splice> above for details.
		2239
		2240	=item $actual_size = IO::AIO::pipesize $r_fh[, $new_size]
		2241
		2242	Attempts to query or change the pipe buffer size. Obviously works only
		2243	on pipes, and currently works only on GNU/Linux systems, and fails with
		2244	C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer
		2245	size on other systems, drop me a note.
		2246
		2247	=item ($rfh, $wfh) = IO::AIO::pipe2 [$flags]
		2248
		2249	This is a direct interface to the Linux L<pipe2(2)> system call. If
		2250	C<$flags> is missing or C<0>, then this should be the same as a call to
		2251	perl's built-in C<pipe> function and create a new pipe, and works on
		2252	systems that lack the pipe2 syscall. On win32, this case invokes C<_pipe
		2253	(..., 4096, O_BINARY)>.
		2254
		2255	If C<$flags> is non-zero, it tries to invoke the pipe2 system call with
		2256	the given flags (Linux 2.6.27, glibc 2.9).
		2257
		2258	On success, the read and write file handles are returned.
		2259
		2260	On error, nothing will be returned. If the pipe2 syscall is missing and
		2261	C<$flags> is non-zero, fails with C<ENOSYS>.
		2262
		2263	Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the
		2264	time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and
		2265	C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported.
2100		2266
2101	=back	2267	=back
2102		2268
2103	=cut	2269	=cut
2104		2270

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Comparing IO-AIO/AIO.pm (file contents): Revision 1.235 by root, Wed Aug 22 22:28:03 2012 UTC vs. Revision 1.276 by root, Fri Sep 22 05:24:41 2017 UTC

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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.235 by root, Wed Aug 22 22:28:03 2012 UTC vs.
Revision 1.276 by root, Fri Sep 22 05:24:41 2017 UTC