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

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.226 by root, Mon May 28 17:00:19 2012 UTC vs.
Revision 1.275 by root, Fri Sep 22 05:20:39 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 = '4.15';	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);
…		…
202		205
203	=head1 FUNCTIONS	206	=head1 FUNCTIONS
204		207
205	=head2 QUICK OVERVIEW	208	=head2 QUICK OVERVIEW
206		209
207	This section simply lists the prototypes of the most important functions	210	This section simply lists the prototypes most of the functions for
208	for quick reference. See the following sections for function-by-function	211	quick reference. See the following sections for function-by-function
209	documentation.	212	documentation.
210		213
211	aio_wd $pathname, $callback->($wd)	214	aio_wd $pathname, $callback->($wd)
212	aio_open $pathname, $flags, $mode, $callback->($fh)	215	aio_open $pathname, $flags, $mode, $callback->($fh)
213	aio_close $fh, $callback->($status)	216	aio_close $fh, $callback->($status)
…		…
221	aio_statvfs $fh_or_path, $callback->($statvfs)	224	aio_statvfs $fh_or_path, $callback->($statvfs)
222	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	225	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
223	aio_chown $fh_or_path, $uid, $gid, $callback->($status)	226	aio_chown $fh_or_path, $uid, $gid, $callback->($status)
224	aio_chmod $fh_or_path, $mode, $callback->($status)	227	aio_chmod $fh_or_path, $mode, $callback->($status)
225	aio_truncate $fh_or_path, $offset, $callback->($status)	228	aio_truncate $fh_or_path, $offset, $callback->($status)
		229	aio_allocate $fh, $mode, $offset, $len, $callback->($status)
		230	aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
226	aio_unlink $pathname, $callback->($status)	231	aio_unlink $pathname, $callback->($status)
227	aio_mknod $pathname, $mode, $dev, $callback->($status)	232	aio_mknod $pathname, $mode, $dev, $callback->($status)
228	aio_link $srcpath, $dstpath, $callback->($status)	233	aio_link $srcpath, $dstpath, $callback->($status)
229	aio_symlink $srcpath, $dstpath, $callback->($status)	234	aio_symlink $srcpath, $dstpath, $callback->($status)
230	aio_readlink $pathname, $callback->($link)	235	aio_readlink $pathname, $callback->($link)
231	aio_realpath $pathname, $callback->($link)	236	aio_realpath $pathname, $callback->($path)
232	aio_rename $srcpath, $dstpath, $callback->($status)	237	aio_rename $srcpath, $dstpath, $callback->($status)
		238	aio_rename2 $srcpath, $dstpath, $flags, $callback->($status)
233	aio_mkdir $pathname, $mode, $callback->($status)	239	aio_mkdir $pathname, $mode, $callback->($status)
234	aio_rmdir $pathname, $callback->($status)	240	aio_rmdir $pathname, $callback->($status)
235	aio_readdir $pathname, $callback->($entries)	241	aio_readdir $pathname, $callback->($entries)
236	aio_readdirx $pathname, $flags, $callback->($entries, $flags)	242	aio_readdirx $pathname, $flags, $callback->($entries, $flags)
237	IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST	243	IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST
…		…
239	aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)	245	aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
240	aio_load $pathname, $data, $callback->($status)	246	aio_load $pathname, $data, $callback->($status)
241	aio_copy $srcpath, $dstpath, $callback->($status)	247	aio_copy $srcpath, $dstpath, $callback->($status)
242	aio_move $srcpath, $dstpath, $callback->($status)	248	aio_move $srcpath, $dstpath, $callback->($status)
243	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)
244	aio_sync $callback->($status)	252	aio_sync $callback->($status)
245	aio_syncfs $fh, $callback->($status)	253	aio_syncfs $fh, $callback->($status)
246	aio_fsync $fh, $callback->($status)	254	aio_fsync $fh, $callback->($status)
247	aio_fdatasync $fh, $callback->($status)	255	aio_fdatasync $fh, $callback->($status)
248	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)	256	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
249	aio_pathsync $pathname, $callback->($status)	257	aio_pathsync $pathname, $callback->($status)
250	aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	258	aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status)
251	aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	259	aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
252	aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)	260	aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
253	aio_mlockall $flags, $callback->($status)	261	aio_mlockall $flags, $callback->($status)
254	aio_group $callback->(...)	262	aio_group $callback->(...)
255	aio_nop $callback->()	263	aio_nop $callback->()
…		…
269	IO::AIO::idle_timeout $seconds	277	IO::AIO::idle_timeout $seconds
270	IO::AIO::max_outstanding $maxreqs	278	IO::AIO::max_outstanding $maxreqs
271	IO::AIO::nreqs	279	IO::AIO::nreqs
272	IO::AIO::nready	280	IO::AIO::nready
273	IO::AIO::npending	281	IO::AIO::npending
		282	IO::AIO::min_fdlimit $nfd;
274		283
275	IO::AIO::sendfile $ofh, $ifh, $offset, $count	284	IO::AIO::sendfile $ofh, $ifh, $offset, $count
276	IO::AIO::fadvise $fh, $offset, $len, $advice	285	IO::AIO::fadvise $fh, $offset, $len, $advice
277	IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]]	286	IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]]
278	IO::AIO::munmap $scalar	287	IO::AIO::munmap $scalar
…		…
360		369
361		370
362	=item aio_open $pathname, $flags, $mode, $callback->($fh)	371	=item aio_open $pathname, $flags, $mode, $callback->($fh)
363		372
364	Asynchronously open or create a file and call the callback with a newly	373	Asynchronously open or create a file and call the callback with a newly
365	created filehandle for the file.	374	created filehandle for the file (or C<undef> in case of an error).
366		375
367	The pathname passed to C<aio_open> must be absolute. See API NOTES, above,	376	The pathname passed to C<aio_open> must be absolute. See API NOTES, above,
368	for an explanation.	377	for an explanation.
369		378
370	The C<$flags> argument is a bitmask. See the C<Fcntl> module for a	379	The C<$flags> argument is a bitmask. See the C<Fcntl> module for a
…		…
393	following POSIX and non-POSIX constants are available (missing ones on	402	following POSIX and non-POSIX constants are available (missing ones on
394	your system are, as usual, C<0>):	403	your system are, as usual, C<0>):
395		404
396	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>,
397	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>,
398	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>.
399		408
400		409
401	=item aio_close $fh, $callback->($status)	410	=item aio_close $fh, $callback->($status)
402		411
403	Asynchronously close a file and call the callback with the result	412	Asynchronously close a file and call the callback with the result
…		…
438	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	447	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
439		448
440	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	449	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
441		450
442	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
443	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
444	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
445	error, just like the syscall).	454	error, just like the syscall).
446		455
447	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
448	offset plus the actual number of bytes read.	457	offset plus the actual number of bytes read.
449		458
…		…
507	As native sendfile syscalls (as practically any non-POSIX interface hacked	516	As native sendfile syscalls (as practically any non-POSIX interface hacked
508	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
509	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
510	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,
511	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> -
512	fewre bytes than expected might have been transferred.	521	fewer bytes than expected might have been transferred.
513		522
514		523
515	=item aio_readahead $fh,$offset,$length, $callback->($retval)	524	=item aio_readahead $fh,$offset,$length, $callback->($retval)
516		525
517	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
…		…
521	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
522	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
523	(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
524	file. The current file offset of the file is left unchanged.	533	file. The current file offset of the file is left unchanged.
525		534
526	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
527	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.
528		537
529		538
530	=item aio_stat $fh_or_path, $callback->($status)	539	=item aio_stat $fh_or_path, $callback->($status)
531		540
532	=item aio_lstat $fh, $callback->($status)	541	=item aio_lstat $fh, $callback->($status)
…		…
601	namemax => 255,	610	namemax => 255,
602	frsize => 1024,	611	frsize => 1024,
603	fsid => 1810	612	fsid => 1810
604	}	613	}
605		614
		615	Here is a (likely partial - send me updates!) list of fsid values used by
		616	Linux - it is safe to hardcode these when C<$^O> is C<linux>:
		617
		618	0x0000adf5 adfs
		619	0x0000adff affs
		620	0x5346414f afs
		621	0x09041934 anon-inode filesystem
		622	0x00000187 autofs
		623	0x42465331 befs
		624	0x1badface bfs
		625	0x42494e4d binfmt_misc
		626	0x9123683e btrfs
		627	0x0027e0eb cgroupfs
		628	0xff534d42 cifs
		629	0x73757245 coda
		630	0x012ff7b7 coh
		631	0x28cd3d45 cramfs
		632	0x453dcd28 cramfs-wend (wrong endianness)
		633	0x64626720 debugfs
		634	0x00001373 devfs
		635	0x00001cd1 devpts
		636	0x0000f15f ecryptfs
		637	0x00414a53 efs
		638	0x0000137d ext
		639	0x0000ef53 ext2/ext3/ext4
		640	0x0000ef51 ext2
		641	0xf2f52010 f2fs
		642	0x00004006 fat
		643	0x65735546 fuseblk
		644	0x65735543 fusectl
		645	0x0bad1dea futexfs
		646	0x01161970 gfs2
		647	0x47504653 gpfs
		648	0x00004244 hfs
		649	0xf995e849 hpfs
		650	0x00c0ffee hostfs
		651	0x958458f6 hugetlbfs
		652	0x2bad1dea inotifyfs
		653	0x00009660 isofs
		654	0x000072b6 jffs2
		655	0x3153464a jfs
		656	0x6b414653 k-afs
		657	0x0bd00bd0 lustre
		658	0x0000137f minix
		659	0x0000138f minix 30 char names
		660	0x00002468 minix v2
		661	0x00002478 minix v2 30 char names
		662	0x00004d5a minix v3
		663	0x19800202 mqueue
		664	0x00004d44 msdos
		665	0x0000564c novell
		666	0x00006969 nfs
		667	0x6e667364 nfsd
		668	0x00003434 nilfs
		669	0x5346544e ntfs
		670	0x00009fa1 openprom
		671	0x7461636F ocfs2
		672	0x00009fa0 proc
		673	0x6165676c pstorefs
		674	0x0000002f qnx4
		675	0x68191122 qnx6
		676	0x858458f6 ramfs
		677	0x52654973 reiserfs
		678	0x00007275 romfs
		679	0x67596969 rpc_pipefs
		680	0x73636673 securityfs
		681	0xf97cff8c selinux
		682	0x0000517b smb
		683	0x534f434b sockfs
		684	0x73717368 squashfs
		685	0x62656572 sysfs
		686	0x012ff7b6 sysv2
		687	0x012ff7b5 sysv4
		688	0x01021994 tmpfs
		689	0x15013346 udf
		690	0x00011954 ufs
		691	0x54190100 ufs byteswapped
		692	0x00009fa2 usbdevfs
		693	0x01021997 v9fs
		694	0xa501fcf5 vxfs
		695	0xabba1974 xenfs
		696	0x012ff7b4 xenix
		697	0x58465342 xfs
		698	0x012fd16d xia
606		699
607	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	700	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
608		701
609	Works like perl's C<utime> function (including the special case of $atime	702	Works like perl's C<utime> function (including the special case of $atime
610	and $mtime being undef). Fractional times are supported if the underlying	703	and $mtime being undef). Fractional times are supported if the underlying
…		…
638	=item aio_truncate $fh_or_path, $offset, $callback->($status)	731	=item aio_truncate $fh_or_path, $offset, $callback->($status)
639		732
640	Works like truncate(2) or ftruncate(2).	733	Works like truncate(2) or ftruncate(2).
641		734
642		735
		736	=item aio_allocate $fh, $mode, $offset, $len, $callback->($status)
		737
		738	Allocates or frees disk space according to the C<$mode> argument. See the
		739	linux C<fallocate> documentation for details.
		740
		741	C<$mode> is usually C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> to allocate
		742	space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE \| IO::AIO::FALLOC_FL_KEEP_SIZE>,
		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).
		749
		750	The file system block size used by C<fallocate> is presumably the
		751	C<f_bsize> returned by C<statvfs>, but different filesystems and filetypes
		752	can dictate other limitations.
		753
		754	If C<fallocate> isn't available or cannot be emulated (currently no
		755	emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>.
		756
		757
643	=item aio_chmod $fh_or_path, $mode, $callback->($status)	758	=item aio_chmod $fh_or_path, $mode, $callback->($status)
644		759
645	Works like perl's C<chmod> function.	760	Works like perl's C<chmod> function.
646		761
647		762
…		…
684		799
685		800
686	=item aio_realpath $pathname, $callback->($path)	801	=item aio_realpath $pathname, $callback->($path)
687		802
688	Asynchronously make the path absolute and resolve any symlinks in	803	Asynchronously make the path absolute and resolve any symlinks in
689	C<$path>. The resulting path only consists of directories (Same as	804	C<$path>. The resulting path only consists of directories (same as
690	L<Cwd::realpath>).	805	L<Cwd::realpath>).
691		806
692	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
693	directory by passing it a path of F<.> (a single dot).	808	directory by passing it a path of F<.> (a single dot).
694		809
695		810
696	=item aio_rename $srcpath, $dstpath, $callback->($status)	811	=item aio_rename $srcpath, $dstpath, $callback->($status)
697		812
698	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
699	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>.
700		835
701		836
702	=item aio_mkdir $pathname, $mode, $callback->($status)	837	=item aio_mkdir $pathname, $mode, $callback->($status)
703		838
704	Asynchronously mkdir (create) a directory and call the callback with	839	Asynchronously mkdir (create) a directory and call the callback with
…		…
708		843
709	=item aio_rmdir $pathname, $callback->($status)	844	=item aio_rmdir $pathname, $callback->($status)
710		845
711	Asynchronously rmdir (delete) a directory and call the callback with the	846	Asynchronously rmdir (delete) a directory and call the callback with the
712	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>.
713		852
714		853
715	=item aio_readdir $pathname, $callback->($entries)	854	=item aio_readdir $pathname, $callback->($entries)
716		855
717	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
…		…
819	=item aio_copy $srcpath, $dstpath, $callback->($status)	958	=item aio_copy $srcpath, $dstpath, $callback->($status)
820		959
821	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
822	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
823	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.
824		965
825	This is a composite request that creates the destination file with	966	This is a composite request that creates the destination file with
826	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
827	C<aio_sendfile>, followed by restoring atime, mtime, access mode and	968	C<aio_sendfile>, followed by restoring atime, mtime, access mode and
828	uid/gid, in that order.	969	uid/gid, in that order.
…		…
1082	}	1223	}
1083		1224
1084	=item aio_rmtree $pathname, $callback->($status)	1225	=item aio_rmtree $pathname, $callback->($status)
1085		1226
1086	Delete a directory tree starting (and including) C<$path>, return the	1227	Delete a directory tree starting (and including) C<$path>, return the
1087	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
1088	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
1089	everything else.	1230	everything else.
1090		1231
1091	=cut	1232	=cut
1092		1233
…		…
1113	add $grp $dirgrp;	1254	add $grp $dirgrp;
1114	};	1255	};
1115		1256
1116	$grp	1257	$grp
1117	}	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>,
1118		1303
1119	=item aio_sync $callback->($status)	1304	=item aio_sync $callback->($status)
1120		1305
1121	Asynchronously call sync and call the callback when finished.	1306	Asynchronously call sync and call the callback when finished.
1122		1307
…		…
1191	};	1376	};
1192		1377
1193	$grp	1378	$grp
1194	}	1379	}
1195		1380
1196	=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)
1197		1382
1198	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
1199	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
1200	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
1201	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
…		…
1203		1388
1204	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
1205	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
1206	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>
1207	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
1208	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
1209	C<IO::AIO::MS_SYNC>.	1394	C<IO::AIO::MS_INVALIDATE>.
1210		1395
1211	=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)
1212		1397
1213	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
1214	scalars.	1399	scalars.
1215		1400
1216	It touches (reads or writes) all memory pages in the specified	1401	It touches (reads or writes) all memory pages in the specified
1217	range inside the scalar. All caveats and parameters are the same	1402	range inside the scalar. All caveats and parameters are the same
1218	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
1219	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
1220	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
1221	writing an octet from it, which dirties the page).	1406	writing an octet from it, which dirties the page).
1222		1407
1223	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)	1408	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
1224		1409
1225	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
…		…
1259		1444
1260	aio_mlockall IO::AIO::MCL_FUTURE;	1445	aio_mlockall IO::AIO::MCL_FUTURE;
1261		1446
1262	=item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)	1447	=item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
1263		1448
1264	Queries the extents of the given file (by calling the Linux FIEMAP ioctl,	1449	Queries the extents of the given file (by calling the Linux C<FIEMAP>
1265	see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If the	1450	ioctl, see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If
1266	C<ioctl> is not available on your OS, then this rquiest will fail with	1451	the ioctl is not available on your OS, then this request will fail with
1267	C<ENOSYS>.	1452	C<ENOSYS>.
1268		1453
1269	C<$start> is the starting offset to query extents for, C<$length> is the	1454	C<$start> is the starting offset to query extents for, C<$length> is the
1270	size of the range to query - if it is C<undef>, then the whole file will	1455	size of the range to query - if it is C<undef>, then the whole file will
1271	be queried.	1456	be queried.
…		…
1274	C<IO::AIO::FIEMAP_FLAG_XATTR> - C<IO::AIO::FIEMAP_FLAGS_COMPAT> is also	1459	C<IO::AIO::FIEMAP_FLAG_XATTR> - C<IO::AIO::FIEMAP_FLAGS_COMPAT> is also
1275	exported), and is normally C<0> or C<IO::AIO::FIEMAP_FLAG_SYNC> to query	1460	exported), and is normally C<0> or C<IO::AIO::FIEMAP_FLAG_SYNC> to query
1276	the data portion.	1461	the data portion.
1277		1462
1278	C<$count> is the maximum number of extent records to return. If it is	1463	C<$count> is the maximum number of extent records to return. If it is
1279	C<undef>, then IO::AIO queries all extents of the file. As a very special	1464	C<undef>, then IO::AIO queries all extents of the range. As a very special
1280	case, if it is C<0>, then the callback receives the number of extents	1465	case, if it is C<0>, then the callback receives the number of extents
1281	instead of the extents themselves.	1466	instead of the extents themselves (which is unreliable, see below).
1282		1467
1283	If an error occurs, the callback receives no arguments. The special	1468	If an error occurs, the callback receives no arguments. The special
1284	C<errno> value C<IO::AIO::EBADR> is available to test for flag errors.	1469	C<errno> value C<IO::AIO::EBADR> is available to test for flag errors.
1285		1470
1286	Otherwise, the callback receives an array reference with extent	1471	Otherwise, the callback receives an array reference with extent
…		…
1288	following members:	1473	following members:
1289		1474
1290	[$logical, $physical, $length, $flags]	1475	[$logical, $physical, $length, $flags]
1291		1476
1292	Flags is any combination of the following flag values (typically either C<0>	1477	Flags is any combination of the following flag values (typically either C<0>
1293	or C<IO::AIO::FIEMAP_EXTENT_LAST>):	1478	or C<IO::AIO::FIEMAP_EXTENT_LAST> (1)):
1294		1479
1295	C<IO::AIO::FIEMAP_EXTENT_LAST>, C<IO::AIO::FIEMAP_EXTENT_UNKNOWN>,	1480	C<IO::AIO::FIEMAP_EXTENT_LAST>, C<IO::AIO::FIEMAP_EXTENT_UNKNOWN>,
1296	C<IO::AIO::FIEMAP_EXTENT_DELALLOC>, C<IO::AIO::FIEMAP_EXTENT_ENCODED>,	1481	C<IO::AIO::FIEMAP_EXTENT_DELALLOC>, C<IO::AIO::FIEMAP_EXTENT_ENCODED>,
1297	C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>,	1482	C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>,
1298	C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>,	1483	C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>,
1299	C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or	1484	C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or
1300	C<IO::AIO::FIEMAP_EXTENT_SHARED>.	1485	C<IO::AIO::FIEMAP_EXTENT_SHARED>.
1301		1486
		1487	At the time of this writing (Linux 3.2), this requets is unreliable unless
		1488	C<$count> is C<undef>, as the kernel has all sorts of bugs preventing
		1489	it to return all extents of a range for files with large number of
		1490	extents. The code works around all these issues if C<$count> is undef.
		1491
1302	=item aio_group $callback->(...)	1492	=item aio_group $callback->(...)
1303		1493
1304	This is a very special aio request: Instead of doing something, it is a	1494	This is a very special aio request: Instead of doing something, it is a
1305	container for other aio requests, which is useful if you want to bundle	1495	container for other aio requests, which is useful if you want to bundle
1306	many requests into a single, composite, request with a definite callback	1496	many requests into a single, composite, request with a definite callback
…		…
1389	aio_stat [$etcdir, "passwd"], sub {	1579	aio_stat [$etcdir, "passwd"], sub {
1390	# yay	1580	# yay
1391	};	1581	};
1392	};	1582	};
1393		1583
1394	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
1395	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,
1396	why it is done asynchronously.	1586	which is why it is done asynchronously.
1397		1587
1398	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
1399	either of the following three request calls:	1589	either of the following three request calls:
1400		1590
1401	aio_lstat "/etc" , sub { ... # pathname as normal string	1591	aio_lstat "/etc" , sub { ... # pathname as normal string
…		…
1421	will still point to the original directory. Most functions accepting a	1611	will still point to the original directory. Most functions accepting a
1422	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
1423	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
1424	string form of the pathname.	1614	string form of the pathname.
1425		1615
1426	So this fucntionality is mainly useful to get some protection against	1616	So this functionality is mainly useful to get some protection against
1427	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
1428	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
1429	(e.g. when stat'ing all files in a directory).	1619	(e.g. when stat'ing all files in a directory).
1430		1620
1431	The following functions implement this working directory abstraction:	1621	The following functions implement this working directory abstraction:
…		…
1444	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
1445	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
1446	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
1447	expected way.	1637	expected way.
1448		1638
1449	If this call isn't available because your OS lacks it or it couldn't be
1450	detected, it will be emulated by calling C<fsync> instead.
1451
1452	=item IO::AIO::CWD	1639	=item IO::AIO::CWD
1453		1640
1454	This is a compiletime constant (object) that represents the process	1641	This is a compiletime constant (object) that represents the process
1455	current working directory.	1642	current working directory.
1456		1643
1457	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
1458	if the pathname would be specified directly, without a directory object,	1645	the pathname would be specified directly, without a directory object. For
1459	e.g., these calls are functionally identical:	1646	example, these calls are functionally identical:
1460		1647
1461	aio_stat "somefile", sub { ... };	1648	aio_stat "somefile", sub { ... };
1462	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };	1649	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };
1463		1650
1464	=back	1651	=back
1465		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.
1466		1662
1467	=head2 IO::AIO::REQ CLASS	1663	=head2 IO::AIO::REQ CLASS
1468		1664
1469	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
1470	called in non-void context.	1666	called in non-void context.
…		…
1648		1844
1649	See C<poll_cb> for an example.	1845	See C<poll_cb> for an example.
1650		1846
1651	=item IO::AIO::poll_cb	1847	=item IO::AIO::poll_cb
1652		1848
1653	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
1654	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
1655	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
1656	reason. Returns immediately when no events are outstanding. The amount of	1855	reason. Returns immediately when no events are outstanding. The amount
1657	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>,
1658	C<IO::AIO::max_poll_time>.	1857	C<IO::AIO::max_poll_time> and C<IO::AIO::max_outstanding>.
1659		1858
1660	If not all requests were processed for whatever reason, the filehandle	1859	If not all requests were processed for whatever reason, the poll file
1661	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
1662	do anything special to have it called later.	1861	don't have to do anything special to have it called later.
1663		1862
1664	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
1665	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
1666	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
1667	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
…		…
1676	poll => 'r', async => 1,	1875	poll => 'r', async => 1,
1677	cb => \&IO::AIO::poll_cb);	1876	cb => \&IO::AIO::poll_cb);
1678		1877
1679	=item IO::AIO::poll_wait	1878	=item IO::AIO::poll_wait
1680		1879
1681	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
1682	phase, wait till the result filehandle becomes ready for reading (simply	1881	requests are outstanding anymore.
1683	does a C<select> on the filehandle. This is useful if you want to	1882
1684	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.
1685		1885
1686	See C<nreqs> for an example.	1886	See C<nreqs> for an example.
1687		1887
1688	=item IO::AIO::poll	1888	=item IO::AIO::poll
1689		1889
…		…
1810		2010
1811	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
1812	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
1813	use an C<aio_group> together with a feed callback.	2013	use an C<aio_group> together with a feed callback.
1814		2014
1815	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
1816	a lot of files, you can write somehting like this:	2016	a lot of files, you can write something like this:
1817		2017
1818	IO::AIO::max_outstanding 32;	2018	IO::AIO::max_outstanding 32;
1819		2019
1820	for my $path (...) {	2020	for my $path (...) {
1821	aio_stat $path , ...;	2021	aio_stat $path , ...;
…		…
1860		2060
1861	=back	2061	=back
1862		2062
1863	=head3 MISCELLANEOUS FUNCTIONS	2063	=head3 MISCELLANEOUS FUNCTIONS
1864		2064
1865	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
1866	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.
1867		2069
1868	=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<$numfd>
		2082	is missing, it will try to set a very high limit, although this is not
		2083	recommended when you know the actual minimum that you require.
		2084
		2085	If the limit cannot be raised enough, the function makes a best-effort
		2086	attempt to increase the limit as much as possible, using various
		2087	tricks, while still failing. You can query the resulting limit using
		2088	C<IO::AIO::get_fdlimit>.
		2089
		2090	If an error occurs, returns C<undef> and sets C<$!>.
1869		2091
1870	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count	2092	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
1871		2093
1872	Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>,	2094	Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>,
1873	but is blocking (this makes most sense if you know the input data is	2095	but is blocking (this makes most sense if you know the input data is
…		…
1890	=item IO::AIO::madvise $scalar, $offset, $len, $advice	2112	=item IO::AIO::madvise $scalar, $offset, $len, $advice
1891		2113
1892	Simply calls the C<posix_madvise> function (see its	2114	Simply calls the C<posix_madvise> function (see its
1893	manpage for details). The following advice constants are	2115	manpage for details). The following advice constants are
1894	available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,	2116	available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,
1895	C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>.	2117	C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>,
		2118	C<IO::AIO::MADV_DONTNEED>.
		2119
		2120	If C<$offset> is negative, counts from the end. If C<$length> is negative,
		2121	the remaining length of the C<$scalar> is used. If possible, C<$length>
		2122	will be reduced to fit into the C<$scalar>.
1896		2123
1897	On systems that do not implement C<posix_madvise>, this function returns	2124	On systems that do not implement C<posix_madvise>, this function returns
1898	ENOSYS, otherwise the return value of C<posix_madvise>.	2125	ENOSYS, otherwise the return value of C<posix_madvise>.
1899		2126
1900	=item IO::AIO::mprotect $scalar, $offset, $len, $protect	2127	=item IO::AIO::mprotect $scalar, $offset, $len, $protect
…		…
1902	Simply calls the C<mprotect> function on the preferably AIO::mmap'ed	2129	Simply calls the C<mprotect> function on the preferably AIO::mmap'ed
1903	$scalar (see its manpage for details). The following protect	2130	$scalar (see its manpage for details). The following protect
1904	constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,	2131	constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,
1905	C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.	2132	C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.
1906		2133
		2134	If C<$offset> is negative, counts from the end. If C<$length> is negative,
		2135	the remaining length of the C<$scalar> is used. If possible, C<$length>
		2136	will be reduced to fit into the C<$scalar>.
		2137
1907	On systems that do not implement C<mprotect>, this function returns	2138	On systems that do not implement C<mprotect>, this function returns
1908	ENOSYS, otherwise the return value of C<mprotect>.	2139	ENOSYS, otherwise the return value of C<mprotect>.
1909		2140
1910	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]	2141	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]
1911		2142
1912	Memory-maps a file (or anonymous memory range) and attaches it to the	2143	Memory-maps a file (or anonymous memory range) and attaches it to the
1913	given C<$scalar>, which will act like a string scalar.	2144	given C<$scalar>, which will act like a string scalar. Returns true on
		2145	success, and false otherwise.
1914		2146
		2147	The scalar must exist, but its contents do not matter - this means you
		2148	cannot use a nonexistant array or hash element. When in doubt, C<undef>
		2149	the scalar first.
		2150
1915	The only operations allowed on the scalar are C<substr>/C<vec> that don't	2151	The only operations allowed on the mmapped scalar are C<substr>/C<vec>,
1916	change the string length, and most read-only operations such as copying it	2152	which don't change the string length, and most read-only operations such
1917	or searching it with regexes and so on.	2153	as copying it or searching it with regexes and so on.
1918		2154
1919	Anything else is unsafe and will, at best, result in memory leaks.	2155	Anything else is unsafe and will, at best, result in memory leaks.
1920		2156
1921	The memory map associated with the C<$scalar> is automatically removed	2157	The memory map associated with the C<$scalar> is automatically removed
1922	when the C<$scalar> is destroyed, or when the C<IO::AIO::mmap> or	2158	when the C<$scalar> is undef'd or destroyed, or when the C<IO::AIO::mmap>
1923	C<IO::AIO::munmap> functions are called.	2159	or C<IO::AIO::munmap> functions are called on it.
1924		2160
1925	This calls the C<mmap>(2) function internally. See your system's manual	2161	This calls the C<mmap>(2) function internally. See your system's manual
1926	page for details on the C<$length>, C<$prot> and C<$flags> parameters.	2162	page for details on the C<$length>, C<$prot> and C<$flags> parameters.
1927		2163
1928	The C<$length> must be larger than zero and smaller than the actual	2164	The C<$length> must be larger than zero and smaller than the actual
1929	filesize.	2165	filesize.
1930		2166
1931	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,	2167	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,
1932	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,	2168	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,
1933		2169
1934	C<$flags> can be a combination of C<IO::AIO::MAP_SHARED> or	2170	C<$flags> can be a combination of
1935	C<IO::AIO::MAP_PRIVATE>, or a number of system-specific flags (when	2171	C<IO::AIO::MAP_SHARED> or
1936	not available, the are defined as 0): C<IO::AIO::MAP_ANONYMOUS>	2172	C<IO::AIO::MAP_PRIVATE>,
		2173	or a number of system-specific flags (when not available, the are C<0>):
1937	(which is set to C<MAP_ANON> if your system only provides this	2174	C<IO::AIO::MAP_ANONYMOUS> (which is set to C<MAP_ANON> if your system only provides this constant),
1938	constant), C<IO::AIO::MAP_HUGETLB>, C<IO::AIO::MAP_LOCKED>,	2175	C<IO::AIO::MAP_LOCKED>,
1939	C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or	2176	C<IO::AIO::MAP_NORESERVE>,
		2177	C<IO::AIO::MAP_POPULATE>,
1940	C<IO::AIO::MAP_NONBLOCK>	2178	C<IO::AIO::MAP_NONBLOCK>,
		2179	C<IO::AIO::MAP_FIXED>,
		2180	C<IO::AIO::MAP_GROWSDOWN>,
		2181	C<IO::AIO::MAP_32BIT>,
		2182	C<IO::AIO::MAP_HUGETLB> or
		2183	C<IO::AIO::MAP_STACK>.
1941		2184
1942	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.	2185	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.
1943		2186
1944	C<$offset> is the offset from the start of the file - it generally must be	2187	C<$offset> is the offset from the start of the file - it generally must be
1945	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.	2188	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.
…		…
1977		2220
1978	Calls the GNU/Linux C<splice(2)> syscall, if available. If C<$r_off> or	2221	Calls the GNU/Linux C<splice(2)> syscall, if available. If C<$r_off> or
1979	C<$w_off> are C<undef>, then C<NULL> is passed for these, otherwise they	2222	C<$w_off> are C<undef>, then C<NULL> is passed for these, otherwise they
1980	should be the file offset.	2223	should be the file offset.
1981		2224
		2225	C<$r_fh> and C<$w_fh> should not refer to the same file, as splice might
		2226	silently corrupt the data in this case.
		2227
1982	The following symbol flag values are available: C<IO::AIO::SPLICE_F_MOVE>,	2228	The following symbol flag values are available: C<IO::AIO::SPLICE_F_MOVE>,
1983	C<IO::AIO::SPLICE_F_NONBLOCK>, C<IO::AIO::SPLICE_F_MORE> and	2229	C<IO::AIO::SPLICE_F_NONBLOCK>, C<IO::AIO::SPLICE_F_MORE> and
1984	C<IO::AIO::SPLICE_F_GIFT>.	2230	C<IO::AIO::SPLICE_F_GIFT>.
1985		2231
1986	See the C<splice(2)> manpage for details.	2232	See the C<splice(2)> manpage for details.
1987		2233
1988	=item IO::AIO::tee $r_fh, $w_fh, $length, $flags	2234	=item IO::AIO::tee $r_fh, $w_fh, $length, $flags
1989		2235
1990	Calls the GNU/Linux C<tee(2)> syscall, see it's manpage and the	2236	Calls the GNU/Linux C<tee(2)> syscall, see its manpage and the
1991	description for C<IO::AIO::splice> above for details.	2237	description for C<IO::AIO::splice> above for details.
		2238
		2239	=item $actual_size = IO::AIO::pipesize $r_fh[, $new_size]
		2240
		2241	Attempts to query or change the pipe buffer size. Obviously works only
		2242	on pipes, and currently works only on GNU/Linux systems, and fails with
		2243	C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer
		2244	size on other systems, drop me a note.
		2245
		2246	=item ($rfh, $wfh) = IO::AIO::pipe2 [$flags]
		2247
		2248	This is a direct interface to the Linux L<pipe2(2)> system call. If
		2249	C<$flags> is missing or C<0>, then this should be the same as a call to
		2250	perl's built-in C<pipe> function and create a new pipe, and works on
		2251	systems that lack the pipe2 syscall. On win32, this case invokes C<_pipe
		2252	(..., 4096, O_BINARY)>.
		2253
		2254	If C<$flags> is non-zero, it tries to invoke the pipe2 system call with
		2255	the given flags (Linux 2.6.27, glibc 2.9).
		2256
		2257	On success, the read and write file handles are returned.
		2258
		2259	On error, nothing will be returned. If the pipe2 syscall is missing and
		2260	C<$flags> is non-zero, fails with C<ENOSYS>.
		2261
		2262	Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the
		2263	time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and
		2264	C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported.
1992		2265
1993	=back	2266	=back
1994		2267
1995	=cut	2268	=cut
1996		2269

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Comparing IO-AIO/AIO.pm (file contents): Revision 1.226 by root, Mon May 28 17:00:19 2012 UTC vs. Revision 1.275 by root, Fri Sep 22 05:20:39 2017 UTC

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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.226 by root, Mon May 28 17:00:19 2012 UTC vs.
Revision 1.275 by root, Fri Sep 22 05:20:39 2017 UTC