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

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.208 by root, Mon Sep 26 20:19:08 2011 UTC vs.
Revision 1.256 by root, Thu Jun 25 15:47:01 2015 UTC

…		…
68	=head2 EXAMPLE	68	=head2 EXAMPLE
69		69
70	This is a simple example that uses the EV module and loads	70	This is a simple example that uses the EV module and loads
71	F</etc/passwd> asynchronously:	71	F</etc/passwd> asynchronously:
72		72
73	use Fcntl;
74	use EV;	73	use EV;
75	use IO::AIO;	74	use IO::AIO;
76		75
77	# register the IO::AIO callback with EV	76	# register the IO::AIO callback with EV
78	my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;	77	my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
…		…
168	use common::sense;	167	use common::sense;
169		168
170	use base 'Exporter';	169	use base 'Exporter';
171		170
172	BEGIN {	171	BEGIN {
173	our $VERSION = '4.0';	172	our $VERSION = 4.32;
174		173
175	our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close	174	our @AIO_REQ = qw(aio_sendfile aio_seek aio_read aio_write aio_open aio_close
176	aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx	175	aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx
177	aio_scandir aio_symlink aio_readlink aio_realpath aio_sync	176	aio_scandir aio_symlink aio_readlink aio_realpath aio_sync
178	aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range aio_fallocate	177	aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range aio_allocate
179	aio_pathsync aio_readahead	178	aio_pathsync aio_readahead aio_fiemap
180	aio_rename aio_link aio_move aio_copy aio_group	179	aio_rename aio_link aio_move aio_copy aio_group
181	aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown	180	aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown
182	aio_chmod aio_utime aio_truncate	181	aio_chmod aio_utime aio_truncate
183	aio_msync aio_mtouch aio_mlock aio_mlockall	182	aio_msync aio_mtouch aio_mlock aio_mlockall
184	aio_statvfs	183	aio_statvfs
…		…
202		201
203	=head1 FUNCTIONS	202	=head1 FUNCTIONS
204		203
205	=head2 QUICK OVERVIEW	204	=head2 QUICK OVERVIEW
206		205
207	This section simply lists the prototypes of the most important functions	206	This section simply lists the prototypes most of the functions for
208	for quick reference. See the following sections for function-by-function	207	quick reference. See the following sections for function-by-function
209	documentation.	208	documentation.
210		209
211	aio_wd $pathname, $callback->($wd)	210	aio_wd $pathname, $callback->($wd)
212	aio_open $pathname, $flags, $mode, $callback->($fh)	211	aio_open $pathname, $flags, $mode, $callback->($fh)
213	aio_close $fh, $callback->($status)	212	aio_close $fh, $callback->($status)
		213	aio_seek $fh,$offset,$whence, $callback->($offs)
214	aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	214	aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
215	aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	215	aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
216	aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)	216	aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
217	aio_readahead $fh,$offset,$length, $callback->($retval)	217	aio_readahead $fh,$offset,$length, $callback->($retval)
218	aio_stat $fh_or_path, $callback->($status)	218	aio_stat $fh_or_path, $callback->($status)
219	aio_lstat $fh, $callback->($status)	219	aio_lstat $fh, $callback->($status)
220	aio_statvfs $fh_or_path, $callback->($statvfs)	220	aio_statvfs $fh_or_path, $callback->($statvfs)
221	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	221	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
222	aio_chown $fh_or_path, $uid, $gid, $callback->($status)	222	aio_chown $fh_or_path, $uid, $gid, $callback->($status)
		223	aio_chmod $fh_or_path, $mode, $callback->($status)
223	aio_truncate $fh_or_path, $offset, $callback->($status)	224	aio_truncate $fh_or_path, $offset, $callback->($status)
224	aio_chmod $fh_or_path, $mode, $callback->($status)	225	aio_allocate $fh, $mode, $offset, $len, $callback->($status)
		226	aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
225	aio_unlink $pathname, $callback->($status)	227	aio_unlink $pathname, $callback->($status)
226	aio_mknod $path, $mode, $dev, $callback->($status)	228	aio_mknod $pathname, $mode, $dev, $callback->($status)
227	aio_link $srcpath, $dstpath, $callback->($status)	229	aio_link $srcpath, $dstpath, $callback->($status)
228	aio_symlink $srcpath, $dstpath, $callback->($status)	230	aio_symlink $srcpath, $dstpath, $callback->($status)
229	aio_readlink $path, $callback->($link)	231	aio_readlink $pathname, $callback->($link)
230	aio_realpath $path, $callback->($link)	232	aio_realpath $pathname, $callback->($path)
231	aio_rename $srcpath, $dstpath, $callback->($status)	233	aio_rename $srcpath, $dstpath, $callback->($status)
232	aio_mkdir $pathname, $mode, $callback->($status)	234	aio_mkdir $pathname, $mode, $callback->($status)
233	aio_rmdir $pathname, $callback->($status)	235	aio_rmdir $pathname, $callback->($status)
234	aio_readdir $pathname, $callback->($entries)	236	aio_readdir $pathname, $callback->($entries)
235	aio_readdirx $pathname, $flags, $callback->($entries, $flags)	237	aio_readdirx $pathname, $flags, $callback->($entries, $flags)
236	IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST	238	IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST
237	IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN	239	IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN
		240	aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
238	aio_load $path, $data, $callback->($status)	241	aio_load $pathname, $data, $callback->($status)
239	aio_copy $srcpath, $dstpath, $callback->($status)	242	aio_copy $srcpath, $dstpath, $callback->($status)
240	aio_move $srcpath, $dstpath, $callback->($status)	243	aio_move $srcpath, $dstpath, $callback->($status)
241	aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
242	aio_rmtree $path, $callback->($status)	244	aio_rmtree $pathname, $callback->($status)
243	aio_sync $callback->($status)	245	aio_sync $callback->($status)
244	aio_syncfs $fh, $callback->($status)	246	aio_syncfs $fh, $callback->($status)
245	aio_fsync $fh, $callback->($status)	247	aio_fsync $fh, $callback->($status)
246	aio_fdatasync $fh, $callback->($status)	248	aio_fdatasync $fh, $callback->($status)
247	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)	249	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
248	aio_pathsync $path, $callback->($status)	250	aio_pathsync $pathname, $callback->($status)
249	aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	251	aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
250	aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	252	aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
251	aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)	253	aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
252	aio_mlockall $flags, $callback->($status)	254	aio_mlockall $flags, $callback->($status)
253	aio_group $callback->(...)	255	aio_group $callback->(...)
…		…
271	IO::AIO::nready	273	IO::AIO::nready
272	IO::AIO::npending	274	IO::AIO::npending
273		275
274	IO::AIO::sendfile $ofh, $ifh, $offset, $count	276	IO::AIO::sendfile $ofh, $ifh, $offset, $count
275	IO::AIO::fadvise $fh, $offset, $len, $advice	277	IO::AIO::fadvise $fh, $offset, $len, $advice
		278	IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]]
		279	IO::AIO::munmap $scalar
276	IO::AIO::madvise $scalar, $offset, $length, $advice	280	IO::AIO::madvise $scalar, $offset, $length, $advice
277	IO::AIO::mprotect $scalar, $offset, $length, $protect	281	IO::AIO::mprotect $scalar, $offset, $length, $protect
278	IO::AIO::munlock $scalar, $offset = 0, $length = undef	282	IO::AIO::munlock $scalar, $offset = 0, $length = undef
279	IO::AIO::munlockall	283	IO::AIO::munlockall
280		284
281	=head2 AIO REQUEST FUNCTIONS	285	=head2 API NOTES
282		286
283	All the C<aio_*> calls are more or less thin wrappers around the syscall	287	All the C<aio_*> calls are more or less thin wrappers around the syscall
284	with the same name (sans C<aio_>). The arguments are similar or identical,	288	with the same name (sans C<aio_>). The arguments are similar or identical,
285	and they all accept an additional (and optional) C<$callback> argument	289	and they all accept an additional (and optional) C<$callback> argument
286	which must be a code reference. This code reference will get called with	290	which must be a code reference. This code reference will be called after
287	the syscall return code (e.g. most syscalls return C<-1> on error, unlike	291	the syscall has been executed in an asynchronous fashion. The results
288	perl, which usually delivers "false") as its sole argument after the given	292	of the request will be passed as arguments to the callback (and, if an
289	syscall has been executed asynchronously.	293	error occured, in C<$!>) - for most requests the syscall return code (e.g.
		294	most syscalls return C<-1> on error, unlike perl, which usually delivers
		295	"false").
		296
		297	Some requests (such as C<aio_readdir>) pass the actual results and
		298	communicate failures by passing C<undef>.
290		299
291	All functions expecting a filehandle keep a copy of the filehandle	300	All functions expecting a filehandle keep a copy of the filehandle
292	internally until the request has finished.	301	internally until the request has finished.
293		302
294	All functions return request objects of type L<IO::AIO::REQ> that allow	303	All functions return request objects of type L<IO::AIO::REQ> that allow
295	further manipulation of those requests while they are in-flight.	304	further manipulation of those requests while they are in-flight.
296		305
297	The pathnames you pass to these routines I<must> be absolute and	306	The pathnames you pass to these routines I<should> be absolute. The
298	encoded as octets. The reason for the former is that at the time the	307	reason for this is that at the time the request is being executed, the
299	request is being executed, the current working directory could have	308	current working directory could have changed. Alternatively, you can
300	changed. Alternatively, you can make sure that you never change the	309	make sure that you never change the current working directory anywhere
301	current working directory anywhere in the program and then use relative	310	in the program and then use relative paths. You can also take advantage
302	paths.	311	of IO::AIOs working directory abstraction, that lets you specify paths
		312	relative to some previously-opened "working directory object" - see the
		313	description of the C<IO::AIO::WD> class later in this document.
303		314
304	To encode pathnames as octets, either make sure you either: a) always pass	315	To encode pathnames as octets, either make sure you either: a) always pass
305	in filenames you got from outside (command line, readdir etc.) without	316	in filenames you got from outside (command line, readdir etc.) without
306	tinkering, b) are ASCII or ISO 8859-1, c) use the Encode module and encode	317	tinkering, b) are in your native filesystem encoding, c) use the Encode
307	your pathnames to the locale (or other) encoding in effect in the user	318	module and encode your pathnames to the locale (or other) encoding in
308	environment, d) use Glib::filename_from_unicode on unicode filenames or e)	319	effect in the user environment, d) use Glib::filename_from_unicode on
309	use something else to ensure your scalar has the correct contents.	320	unicode filenames or e) use something else to ensure your scalar has the
		321	correct contents.
310		322
311	This works, btw. independent of the internal UTF-8 bit, which IO::AIO	323	This works, btw. independent of the internal UTF-8 bit, which IO::AIO
312	handles correctly whether it is set or not.	324	handles correctly whether it is set or not.
		325
		326	=head2 AIO REQUEST FUNCTIONS
313		327
314	=over 4	328	=over 4
315		329
316	=item $prev_pri = aioreq_pri [$pri]	330	=item $prev_pri = aioreq_pri [$pri]
317		331
…		…
347		361
348		362
349	=item aio_open $pathname, $flags, $mode, $callback->($fh)	363	=item aio_open $pathname, $flags, $mode, $callback->($fh)
350		364
351	Asynchronously open or create a file and call the callback with a newly	365	Asynchronously open or create a file and call the callback with a newly
352	created filehandle for the file.	366	created filehandle for the file (or C<undef> in case of an error).
353		367
354	The pathname passed to C<aio_open> must be absolute. See API NOTES, above,	368	The pathname passed to C<aio_open> must be absolute. See API NOTES, above,
355	for an explanation.	369	for an explanation.
356		370
357	The C<$flags> argument is a bitmask. See the C<Fcntl> module for a	371	The C<$flags> argument is a bitmask. See the C<Fcntl> module for a
…		…
380	following POSIX and non-POSIX constants are available (missing ones on	394	following POSIX and non-POSIX constants are available (missing ones on
381	your system are, as usual, C<0>):	395	your system are, as usual, C<0>):
382		396
383	C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,	397	C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,
384	C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>,	398	C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>,
385	C<O_RSYNC>, C<O_SYNC> and C<O_TTY_INIT>.	399	C<O_RSYNC>, C<O_SYNC>, C<O_PATH>, C<O_TMPFILE>, and C<O_TTY_INIT>.
386		400
387		401
388	=item aio_close $fh, $callback->($status)	402	=item aio_close $fh, $callback->($status)
389		403
390	Asynchronously close a file and call the callback with the result	404	Asynchronously close a file and call the callback with the result
…		…
399		413
400	Or in other words: the file descriptor will be closed, but it will not be	414	Or in other words: the file descriptor will be closed, but it will not be
401	free for reuse until the perl filehandle is closed.	415	free for reuse until the perl filehandle is closed.
402		416
403	=cut	417	=cut
		418
		419	=item aio_seek $fh, $offset, $whence, $callback->($offs)
		420
		421	Seeks the filehandle to the new C<$offset>, similarly to perl's
		422	C<sysseek>. The C<$whence> can use the traditional values (C<0> for
		423	C<IO::AIO::SEEK_SET>, C<1> for C<IO::AIO::SEEK_CUR> or C<2> for
		424	C<IO::AIO::SEEK_END>).
		425
		426	The resulting absolute offset will be passed to the callback, or C<-1> in
		427	case of an error.
		428
		429	In theory, the C<$whence> constants could be different than the
		430	corresponding values from L<Fcntl>, but perl guarantees they are the same,
		431	so don't panic.
		432
		433	As a GNU/Linux (and maybe Solaris) extension, also the constants
		434	C<IO::AIO::SEEK_DATA> and C<IO::AIO::SEEK_HOLE> are available, if they
		435	could be found. No guarantees about suitability for use in C<aio_seek> or
		436	Perl's C<sysseek> can be made though, although I would naively assume they
		437	"just work".
404		438
405	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	439	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
406		440
407	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	441	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
408		442
…		…
568	namemax => 255,	602	namemax => 255,
569	frsize => 1024,	603	frsize => 1024,
570	fsid => 1810	604	fsid => 1810
571	}	605	}
572		606
		607	Here is a (likely partial - send me updates!) list of fsid values used by
		608	Linux - it is safe to hardcode these when C<$^O> is C<linux>:
		609
		610	0x0000adf5 adfs
		611	0x0000adff affs
		612	0x5346414f afs
		613	0x09041934 anon-inode filesystem
		614	0x00000187 autofs
		615	0x42465331 befs
		616	0x1badface bfs
		617	0x42494e4d binfmt_misc
		618	0x9123683e btrfs
		619	0x0027e0eb cgroupfs
		620	0xff534d42 cifs
		621	0x73757245 coda
		622	0x012ff7b7 coh
		623	0x28cd3d45 cramfs
		624	0x453dcd28 cramfs-wend (wrong endianness)
		625	0x64626720 debugfs
		626	0x00001373 devfs
		627	0x00001cd1 devpts
		628	0x0000f15f ecryptfs
		629	0x00414a53 efs
		630	0x0000137d ext
		631	0x0000ef53 ext2/ext3
		632	0x0000ef51 ext2
		633	0x00004006 fat
		634	0x65735546 fuseblk
		635	0x65735543 fusectl
		636	0x0bad1dea futexfs
		637	0x01161970 gfs2
		638	0x47504653 gpfs
		639	0x00004244 hfs
		640	0xf995e849 hpfs
		641	0x958458f6 hugetlbfs
		642	0x2bad1dea inotifyfs
		643	0x00009660 isofs
		644	0x000072b6 jffs2
		645	0x3153464a jfs
		646	0x6b414653 k-afs
		647	0x0bd00bd0 lustre
		648	0x0000137f minix
		649	0x0000138f minix 30 char names
		650	0x00002468 minix v2
		651	0x00002478 minix v2 30 char names
		652	0x00004d5a minix v3
		653	0x19800202 mqueue
		654	0x00004d44 msdos
		655	0x0000564c novell
		656	0x00006969 nfs
		657	0x6e667364 nfsd
		658	0x00003434 nilfs
		659	0x5346544e ntfs
		660	0x00009fa1 openprom
		661	0x7461636F ocfs2
		662	0x00009fa0 proc
		663	0x6165676c pstorefs
		664	0x0000002f qnx4
		665	0x858458f6 ramfs
		666	0x52654973 reiserfs
		667	0x00007275 romfs
		668	0x67596969 rpc_pipefs
		669	0x73636673 securityfs
		670	0xf97cff8c selinux
		671	0x0000517b smb
		672	0x534f434b sockfs
		673	0x73717368 squashfs
		674	0x62656572 sysfs
		675	0x012ff7b6 sysv2
		676	0x012ff7b5 sysv4
		677	0x01021994 tmpfs
		678	0x15013346 udf
		679	0x00011954 ufs
		680	0x54190100 ufs byteswapped
		681	0x00009fa2 usbdevfs
		682	0x01021997 v9fs
		683	0xa501fcf5 vxfs
		684	0xabba1974 xenfs
		685	0x012ff7b4 xenix
		686	0x58465342 xfs
		687	0x012fd16d xia
573		688
574	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	689	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
575		690
576	Works like perl's C<utime> function (including the special case of $atime	691	Works like perl's C<utime> function (including the special case of $atime
577	and $mtime being undef). Fractional times are supported if the underlying	692	and $mtime being undef). Fractional times are supported if the underlying
…		…
605	=item aio_truncate $fh_or_path, $offset, $callback->($status)	720	=item aio_truncate $fh_or_path, $offset, $callback->($status)
606		721
607	Works like truncate(2) or ftruncate(2).	722	Works like truncate(2) or ftruncate(2).
608		723
609		724
		725	=item aio_allocate $fh, $mode, $offset, $len, $callback->($status)
		726
		727	Allocates or frees disk space according to the C<$mode> argument. See the
		728	linux C<fallocate> documentation for details.
		729
		730	C<$mode> is usually C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> to allocate
		731	space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE \| IO::AIO::FALLOC_FL_KEEP_SIZE>,
		732	to deallocate a file range.
		733
		734	IO::AIO also supports C<FALLOC_FL_COLLAPSE_RANGE>, to remove a range
		735	(without leaving a hole) and C<FALLOC_FL_ZERO_RANGE>, to zero a range (see
		736	your L<fallocate(2)> manpage).
		737
		738	The file system block size used by C<fallocate> is presumably the
		739	C<f_bsize> returned by C<statvfs>.
		740
		741	If C<fallocate> isn't available or cannot be emulated (currently no
		742	emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>.
		743
		744
610	=item aio_chmod $fh_or_path, $mode, $callback->($status)	745	=item aio_chmod $fh_or_path, $mode, $callback->($status)
611		746
612	Works like perl's C<chmod> function.	747	Works like perl's C<chmod> function.
613		748
614		749
…		…
616		751
617	Asynchronously unlink (delete) a file and call the callback with the	752	Asynchronously unlink (delete) a file and call the callback with the
618	result code.	753	result code.
619		754
620		755
621	=item aio_mknod $path, $mode, $dev, $callback->($status)	756	=item aio_mknod $pathname, $mode, $dev, $callback->($status)
622		757
623	[EXPERIMENTAL]	758	[EXPERIMENTAL]
624		759
625	Asynchronously create a device node (or fifo). See mknod(2).	760	Asynchronously create a device node (or fifo). See mknod(2).
626		761
627	The only (POSIX-) portable way of calling this function is:	762	The only (POSIX-) portable way of calling this function is:
628		763
629	aio_mknod $path, IO::AIO::S_IFIFO \| $mode, 0, sub { ...	764	aio_mknod $pathname, IO::AIO::S_IFIFO \| $mode, 0, sub { ...
630		765
631	See C<aio_stat> for info about some potentially helpful extra constants	766	See C<aio_stat> for info about some potentially helpful extra constants
632	and functions.	767	and functions.
633		768
634	=item aio_link $srcpath, $dstpath, $callback->($status)	769	=item aio_link $srcpath, $dstpath, $callback->($status)
…		…
641		776
642	Asynchronously create a new symbolic link to the existing object at C<$srcpath> at	777	Asynchronously create a new symbolic link to the existing object at C<$srcpath> at
643	the path C<$dstpath> and call the callback with the result code.	778	the path C<$dstpath> and call the callback with the result code.
644		779
645		780
646	=item aio_readlink $path, $callback->($link)	781	=item aio_readlink $pathname, $callback->($link)
647		782
648	Asynchronously read the symlink specified by C<$path> and pass it to	783	Asynchronously read the symlink specified by C<$path> and pass it to
649	the callback. If an error occurs, nothing or undef gets passed to the	784	the callback. If an error occurs, nothing or undef gets passed to the
650	callback.	785	callback.
651		786
652		787
653	=item aio_realpath $path, $callback->($path)	788	=item aio_realpath $pathname, $callback->($path)
654		789
655	Asynchronously make the path absolute and resolve any symlinks in	790	Asynchronously make the path absolute and resolve any symlinks in
656	C<$path>. The resulting path only consists of directories (Same as	791	C<$path>. The resulting path only consists of directories (same as
657	L<Cwd::realpath>).	792	L<Cwd::realpath>).
658		793
659	This request can be used to get the absolute path of the current working	794	This request can be used to get the absolute path of the current working
660	directory by passing it a path of F<.> (a single dot).	795	directory by passing it a path of F<.> (a single dot).
661		796
662		797
663	=item aio_rename $srcpath, $dstpath, $callback->($status)	798	=item aio_rename $srcpath, $dstpath, $callback->($status)
664		799
665	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as	800	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as
666	rename(2) and call the callback with the result code.	801	rename(2) and call the callback with the result code.
		802
		803	On systems that support the AIO::WD working directory abstraction
		804	natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead
		805	of failing, C<rename> is called on the absolute path of C<$wd>.
667		806
668		807
669	=item aio_mkdir $pathname, $mode, $callback->($status)	808	=item aio_mkdir $pathname, $mode, $callback->($status)
670		809
671	Asynchronously mkdir (create) a directory and call the callback with	810	Asynchronously mkdir (create) a directory and call the callback with
…		…
675		814
676	=item aio_rmdir $pathname, $callback->($status)	815	=item aio_rmdir $pathname, $callback->($status)
677		816
678	Asynchronously rmdir (delete) a directory and call the callback with the	817	Asynchronously rmdir (delete) a directory and call the callback with the
679	result code.	818	result code.
		819
		820	On systems that support the AIO::WD working directory abstraction
		821	natively, the case C<[$wd, "."]> is specialcased - instead of failing,
		822	C<rmdir> is called on the absolute path of C<$wd>.
680		823
681		824
682	=item aio_readdir $pathname, $callback->($entries)	825	=item aio_readdir $pathname, $callback->($entries)
683		826
684	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire	827	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire
…		…
753	C<$type>'s are known, which can be used to speed up some algorithms.	896	C<$type>'s are known, which can be used to speed up some algorithms.
754		897
755	=back	898	=back
756		899
757		900
758	=item aio_load $path, $data, $callback->($status)	901	=item aio_load $pathname, $data, $callback->($status)
759		902
760	This is a composite request that tries to fully load the given file into	903	This is a composite request that tries to fully load the given file into
761	memory. Status is the same as with aio_read.	904	memory. Status is the same as with aio_read.
762		905
763	=cut	906	=cut
…		…
898	};	1041	};
899		1042
900	$grp	1043	$grp
901	}	1044	}
902		1045
903	=item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)	1046	=item aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
904		1047
905	Scans a directory (similar to C<aio_readdir>) but additionally tries to	1048	Scans a directory (similar to C<aio_readdir>) but additionally tries to
906	efficiently separate the entries of directory C<$path> into two sets of	1049	efficiently separate the entries of directory C<$path> into two sets of
907	names, directories you can recurse into (directories), and ones you cannot	1050	names, directories you can recurse into (directories), and ones you cannot
908	recurse into (everything else, including symlinks to directories).	1051	recurse into (everything else, including symlinks to directories).
…		…
965		1108
966	my $grp = aio_group $cb;	1109	my $grp = aio_group $cb;
967		1110
968	$maxreq = 4 if $maxreq <= 0;	1111	$maxreq = 4 if $maxreq <= 0;
969		1112
970	# stat once	1113	# get a wd object
971	aioreq_pri $pri;	1114	aioreq_pri $pri;
972	add $grp aio_stat $path, sub {	1115	add $grp aio_wd $path, sub {
		1116	$_[0]
973	return $grp->result () if $_[0];	1117	or return $grp->result ();
974	my $now = time;
975	my $hash1 = join ":", (stat _)[0,1,3,7,9];
976		1118
977	# read the directory entries	1119	my $wd = [shift, "."];
		1120
		1121	# stat once
978	aioreq_pri $pri;	1122	aioreq_pri $pri;
979	add $grp aio_readdirx $path, READDIR_DIRS_FIRST, sub {	1123	add $grp aio_stat $wd, sub {
980	my $entries = shift
981	or return $grp->result ();	1124	return $grp->result () if $_[0];
		1125	my $now = time;
		1126	my $hash1 = join ":", (stat _)[0,1,3,7,9];
982		1127
983	# stat the dir another time	1128	# read the directory entries
984	aioreq_pri $pri;	1129	aioreq_pri $pri;
		1130	add $grp aio_readdirx $wd, READDIR_DIRS_FIRST, sub {
		1131	my $entries = shift
		1132	or return $grp->result ();
		1133
		1134	# stat the dir another time
		1135	aioreq_pri $pri;
985	add $grp aio_stat $path, sub {	1136	add $grp aio_stat $wd, sub {
986	my $hash2 = join ":", (stat _)[0,1,3,7,9];	1137	my $hash2 = join ":", (stat _)[0,1,3,7,9];
987		1138
988	my $ndirs;	1139	my $ndirs;
989		1140
990	# take the slow route if anything looks fishy	1141	# take the slow route if anything looks fishy
991	if ($hash1 ne $hash2 or (stat _)[9] == $now) {	1142	if ($hash1 ne $hash2 or (stat _)[9] == $now) {
992	$ndirs = -1;	1143	$ndirs = -1;
993	} else {	1144	} else {
994	# if nlink == 2, we are finished	1145	# if nlink == 2, we are finished
995	# for non-posix-fs's, we rely on nlink < 2	1146	# for non-posix-fs's, we rely on nlink < 2
996	$ndirs = (stat _)[3] - 2	1147	$ndirs = (stat _)[3] - 2
997	or return $grp->result ([], $entries);	1148	or return $grp->result ([], $entries);
998	}	1149	}
999		1150
1000	my (@dirs, @nondirs);	1151	my (@dirs, @nondirs);
1001		1152
1002	my $statgrp = add $grp aio_group sub {	1153	my $statgrp = add $grp aio_group sub {
1003	$grp->result (\@dirs, \@nondirs);	1154	$grp->result (\@dirs, \@nondirs);
1004	};	1155	};
1005		1156
1006	limit $statgrp $maxreq;	1157	limit $statgrp $maxreq;
1007	feed $statgrp sub {	1158	feed $statgrp sub {
1008	return unless @$entries;	1159	return unless @$entries;
1009	my $entry = shift @$entries;	1160	my $entry = shift @$entries;
1010		1161
1011	aioreq_pri $pri;	1162	aioreq_pri $pri;
		1163	$wd->[1] = "$entry/.";
1012	add $statgrp aio_stat "$path/$entry/.", sub {	1164	add $statgrp aio_stat $wd, sub {
1013	if ($_[0] < 0) {	1165	if ($_[0] < 0) {
1014	push @nondirs, $entry;	1166	push @nondirs, $entry;
1015	} else {	1167	} else {
1016	# need to check for real directory	1168	# need to check for real directory
1017	aioreq_pri $pri;	1169	aioreq_pri $pri;
		1170	$wd->[1] = $entry;
1018	add $statgrp aio_lstat "$path/$entry", sub {	1171	add $statgrp aio_lstat $wd, sub {
1019	if (-d _) {	1172	if (-d _) {
1020	push @dirs, $entry;	1173	push @dirs, $entry;
1021		1174
1022	unless (--$ndirs) {	1175	unless (--$ndirs) {
1023	push @nondirs, @$entries;	1176	push @nondirs, @$entries;
1024	feed $statgrp;	1177	feed $statgrp;
		1178	}
		1179	} else {
		1180	push @nondirs, $entry;
1025	}	1181	}
1026	} else {
1027	push @nondirs, $entry;
1028	}	1182	}
1029	}	1183	}
1030	}	1184	};
1031	};	1185	};
1032	};	1186	};
1033	};	1187	};
1034	};	1188	};
1035	};	1189	};
1036		1190
1037	$grp	1191	$grp
1038	}	1192	}
1039		1193
1040	=item aio_rmtree $path, $callback->($status)	1194	=item aio_rmtree $pathname, $callback->($status)
1041		1195
1042	Delete a directory tree starting (and including) C<$path>, return the	1196	Delete a directory tree starting (and including) C<$path>, return the
1043	status of the final C<rmdir> only. This is a composite request that	1197	status of the final C<rmdir> only. This is a composite request that
1044	uses C<aio_scandir> to recurse into and rmdir directories, and unlink	1198	uses C<aio_scandir> to recurse into and rmdir directories, and unlink
1045	everything else.	1199	everything else.
1046		1200
1047	=cut	1201	=cut
1048		1202
…		…
1106	C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>,	1260	C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>,
1107	C<IO::AIO::SYNC_FILE_RANGE_WRITE> and	1261	C<IO::AIO::SYNC_FILE_RANGE_WRITE> and
1108	C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range	1262	C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range
1109	manpage for details.	1263	manpage for details.
1110		1264
1111	=item aio_pathsync $path, $callback->($status)	1265	=item aio_pathsync $pathname, $callback->($status)
1112		1266
1113	This request tries to open, fsync and close the given path. This is a	1267	This request tries to open, fsync and close the given path. This is a
1114	composite request intended to sync directories after directory operations	1268	composite request intended to sync directories after directory operations
1115	(E.g. rename). This might not work on all operating systems or have any	1269	(E.g. rename). This might not work on all operating systems or have any
1116	specific effect, but usually it makes sure that directory changes get	1270	specific effect, but usually it makes sure that directory changes get
…		…
1168		1322
1169	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1323	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
1170	scalars.	1324	scalars.
1171		1325
1172	It touches (reads or writes) all memory pages in the specified	1326	It touches (reads or writes) all memory pages in the specified
1173	range inside the scalar. All caveats and parameters are the same	1327	range inside the scalar. All caveats and parameters are the same
1174	as for C<aio_msync>, above, except for flags, which must be either	1328	as for C<aio_msync>, above, except for flags, which must be either
1175	C<0> (which reads all pages and ensures they are instantiated) or	1329	C<0> (which reads all pages and ensures they are instantiated) or
1176	C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and	1330	C<IO::AIO::MT_MODIFY>, which modifies the memory pages (by reading and
1177	writing an octet from it, which dirties the page).	1331	writing an octet from it, which dirties the page).
1178		1332
1179	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)	1333	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
1180		1334
1181	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1335	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
…		…
1212	documented under L<MISCELLANEOUS FUNCTIONS>.	1366	documented under L<MISCELLANEOUS FUNCTIONS>.
1213		1367
1214	Example: asynchronously lock all current and future pages into memory.	1368	Example: asynchronously lock all current and future pages into memory.
1215		1369
1216	aio_mlockall IO::AIO::MCL_FUTURE;	1370	aio_mlockall IO::AIO::MCL_FUTURE;
		1371
		1372	=item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
		1373
		1374	Queries the extents of the given file (by calling the Linux C<FIEMAP>
		1375	ioctl, see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If
		1376	the ioctl is not available on your OS, then this request will fail with
		1377	C<ENOSYS>.
		1378
		1379	C<$start> is the starting offset to query extents for, C<$length> is the
		1380	size of the range to query - if it is C<undef>, then the whole file will
		1381	be queried.
		1382
		1383	C<$flags> is a combination of flags (C<IO::AIO::FIEMAP_FLAG_SYNC> or
		1384	C<IO::AIO::FIEMAP_FLAG_XATTR> - C<IO::AIO::FIEMAP_FLAGS_COMPAT> is also
		1385	exported), and is normally C<0> or C<IO::AIO::FIEMAP_FLAG_SYNC> to query
		1386	the data portion.
		1387
		1388	C<$count> is the maximum number of extent records to return. If it is
		1389	C<undef>, then IO::AIO queries all extents of the range. As a very special
		1390	case, if it is C<0>, then the callback receives the number of extents
		1391	instead of the extents themselves (which is unreliable, see below).
		1392
		1393	If an error occurs, the callback receives no arguments. The special
		1394	C<errno> value C<IO::AIO::EBADR> is available to test for flag errors.
		1395
		1396	Otherwise, the callback receives an array reference with extent
		1397	structures. Each extent structure is an array reference itself, with the
		1398	following members:
		1399
		1400	[$logical, $physical, $length, $flags]
		1401
		1402	Flags is any combination of the following flag values (typically either C<0>
		1403	or C<IO::AIO::FIEMAP_EXTENT_LAST> (1)):
		1404
		1405	C<IO::AIO::FIEMAP_EXTENT_LAST>, C<IO::AIO::FIEMAP_EXTENT_UNKNOWN>,
		1406	C<IO::AIO::FIEMAP_EXTENT_DELALLOC>, C<IO::AIO::FIEMAP_EXTENT_ENCODED>,
		1407	C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>,
		1408	C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>,
		1409	C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or
		1410	C<IO::AIO::FIEMAP_EXTENT_SHARED>.
		1411
		1412	At the time of this writing (Linux 3.2), this requets is unreliable unless
		1413	C<$count> is C<undef>, as the kernel has all sorts of bugs preventing
		1414	it to return all extents of a range for files with large number of
		1415	extents. The code works around all these issues if C<$count> is undef.
1217		1416
1218	=item aio_group $callback->(...)	1417	=item aio_group $callback->(...)
1219		1418
1220	This is a very special aio request: Instead of doing something, it is a	1419	This is a very special aio request: Instead of doing something, it is a
1221	container for other aio requests, which is useful if you want to bundle	1420	container for other aio requests, which is useful if you want to bundle
…		…
1258	like sleep and file handle readable/writable, the overhead this creates is	1457	like sleep and file handle readable/writable, the overhead this creates is
1259	immense (it blocks a thread for a long time) so do not use this function	1458	immense (it blocks a thread for a long time) so do not use this function
1260	except to put your application under artificial I/O pressure.	1459	except to put your application under artificial I/O pressure.
1261		1460
1262	=back	1461	=back
		1462
		1463
		1464	=head2 IO::AIO::WD - multiple working directories
		1465
		1466	Your process only has one current working directory, which is used by all
		1467	threads. This makes it hard to use relative paths (some other component
		1468	could call C<chdir> at any time, and it is hard to control when the path
		1469	will be used by IO::AIO).
		1470
		1471	One solution for this is to always use absolute paths. This usually works,
		1472	but can be quite slow (the kernel has to walk the whole path on every
		1473	access), and can also be a hassle to implement.
		1474
		1475	Newer POSIX systems have a number of functions (openat, fdopendir,
		1476	futimensat and so on) that make it possible to specify working directories
		1477	per operation.
		1478
		1479	For portability, and because the clowns who "designed", or shall I write,
		1480	perpetrated this new interface were obviously half-drunk, this abstraction
		1481	cannot be perfect, though.
		1482
		1483	IO::AIO allows you to convert directory paths into a so-called IO::AIO::WD
		1484	object. This object stores the canonicalised, absolute version of the
		1485	path, and on systems that allow it, also a directory file descriptor.
		1486
		1487	Everywhere where a pathname is accepted by IO::AIO (e.g. in C<aio_stat>
		1488	or C<aio_unlink>), one can specify an array reference with an IO::AIO::WD
		1489	object and a pathname instead (or the IO::AIO::WD object alone, which
		1490	gets interpreted as C<[$wd, "."]>). If the pathname is absolute, the
		1491	IO::AIO::WD object is ignored, otherwise the pathname is resolved relative
		1492	to that IO::AIO::WD object.
		1493
		1494	For example, to get a wd object for F</etc> and then stat F<passwd>
		1495	inside, you would write:
		1496
		1497	aio_wd "/etc", sub {
		1498	my $etcdir = shift;
		1499
		1500	# although $etcdir can be undef on error, there is generally no reason
		1501	# to check for errors here, as aio_stat will fail with ENOENT
		1502	# when $etcdir is undef.
		1503
		1504	aio_stat [$etcdir, "passwd"], sub {
		1505	# yay
		1506	};
		1507	};
		1508
		1509	The fact that C<aio_wd> is a request and not a normal function shows that
		1510	creating an IO::AIO::WD object is itself a potentially blocking operation,
		1511	which is why it is done asynchronously.
		1512
		1513	To stat the directory obtained with C<aio_wd> above, one could write
		1514	either of the following three request calls:
		1515
		1516	aio_lstat "/etc" , sub { ... # pathname as normal string
		1517	aio_lstat [$wd, "."], sub { ... # "." relative to $wd (i.e. $wd itself)
		1518	aio_lstat $wd , sub { ... # shorthand for the previous
		1519
		1520	As with normal pathnames, IO::AIO keeps a copy of the working directory
		1521	object and the pathname string, so you could write the following without
		1522	causing any issues due to C<$path> getting reused:
		1523
		1524	my $path = [$wd, undef];
		1525
		1526	for my $name (qw(abc def ghi)) {
		1527	$path->[1] = $name;
		1528	aio_stat $path, sub {
		1529	# ...
		1530	};
		1531	}
		1532
		1533	There are some caveats: when directories get renamed (or deleted), the
		1534	pathname string doesn't change, so will point to the new directory (or
		1535	nowhere at all), while the directory fd, if available on the system,
		1536	will still point to the original directory. Most functions accepting a
		1537	pathname will use the directory fd on newer systems, and the string on
		1538	older systems. Some functions (such as realpath) will always rely on the
		1539	string form of the pathname.
		1540
		1541	So this functionality is mainly useful to get some protection against
		1542	C<chdir>, to easily get an absolute path out of a relative path for future
		1543	reference, and to speed up doing many operations in the same directory
		1544	(e.g. when stat'ing all files in a directory).
		1545
		1546	The following functions implement this working directory abstraction:
		1547
		1548	=over 4
		1549
		1550	=item aio_wd $pathname, $callback->($wd)
		1551
		1552	Asynchonously canonicalise the given pathname and convert it to an
		1553	IO::AIO::WD object representing it. If possible and supported on the
		1554	system, also open a directory fd to speed up pathname resolution relative
		1555	to this working directory.
		1556
		1557	If something goes wrong, then C<undef> is passwd to the callback instead
		1558	of a working directory object and C<$!> is set appropriately. Since
		1559	passing C<undef> as working directory component of a pathname fails the
		1560	request with C<ENOENT>, there is often no need for error checking in the
		1561	C<aio_wd> callback, as future requests using the value will fail in the
		1562	expected way.
		1563
		1564	=item IO::AIO::CWD
		1565
		1566	This is a compiletime constant (object) that represents the process
		1567	current working directory.
		1568
		1569	Specifying this object as working directory object for a pathname is as if
		1570	the pathname would be specified directly, without a directory object. For
		1571	example, these calls are functionally identical:
		1572
		1573	aio_stat "somefile", sub { ... };
		1574	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };
		1575
		1576	=back
		1577
		1578	To recover the path associated with an IO::AIO::WD object, you can use
		1579	C<aio_realpath>:
		1580
		1581	aio_realpath $wd, sub {
		1582	warn "path is $_[0]\n";
		1583	};
		1584
		1585	Currently, C<aio_statvfs> always, and C<aio_rename> and C<aio_rmdir>
		1586	sometimes, fall back to using an absolue path.
1263		1587
1264	=head2 IO::AIO::REQ CLASS	1588	=head2 IO::AIO::REQ CLASS
1265		1589
1266	All non-aggregate C<aio_*> functions return an object of this class when	1590	All non-aggregate C<aio_*> functions return an object of this class when
1267	called in non-void context.	1591	called in non-void context.
…		…
1385		1709
1386	Sets a feeder/generator on this group: every group can have an attached	1710	Sets a feeder/generator on this group: every group can have an attached
1387	generator that generates requests if idle. The idea behind this is that,	1711	generator that generates requests if idle. The idea behind this is that,
1388	although you could just queue as many requests as you want in a group,	1712	although you could just queue as many requests as you want in a group,
1389	this might starve other requests for a potentially long time. For example,	1713	this might starve other requests for a potentially long time. For example,
1390	C<aio_scandir> might generate hundreds of thousands C<aio_stat> requests,	1714	C<aio_scandir> might generate hundreds of thousands of C<aio_stat>
1391	delaying any later requests for a long time.	1715	requests, delaying any later requests for a long time.
1392		1716
1393	To avoid this, and allow incremental generation of requests, you can	1717	To avoid this, and allow incremental generation of requests, you can
1394	instead a group and set a feeder on it that generates those requests. The	1718	instead a group and set a feeder on it that generates those requests. The
1395	feed callback will be called whenever there are few enough (see C<limit>,	1719	feed callback will be called whenever there are few enough (see C<limit>,
1396	below) requests active in the group itself and is expected to queue more	1720	below) requests active in the group itself and is expected to queue more
…		…
1445		1769
1446	See C<poll_cb> for an example.	1770	See C<poll_cb> for an example.
1447		1771
1448	=item IO::AIO::poll_cb	1772	=item IO::AIO::poll_cb
1449		1773
1450	Process some outstanding events on the result pipe. You have to call	1774	Process some requests that have reached the result phase (i.e. they have
		1775	been executed but the results are not yet reported). You have to call
		1776	this "regularly" to finish outstanding requests.
		1777
1451	this regularly. Returns C<0> if all events could be processed (or there	1778	Returns C<0> if all events could be processed (or there were no
1452	were no events to process), or C<-1> if it returned earlier for whatever	1779	events to process), or C<-1> if it returned earlier for whatever
1453	reason. Returns immediately when no events are outstanding. The amount of	1780	reason. Returns immediately when no events are outstanding. The amount
1454	events processed depends on the settings of C<IO::AIO::max_poll_req> and	1781	of events processed depends on the settings of C<IO::AIO::max_poll_req>,
1455	C<IO::AIO::max_poll_time>.	1782	C<IO::AIO::max_poll_time> and C<IO::AIO::max_outstanding>.
1456		1783
1457	If not all requests were processed for whatever reason, the filehandle	1784	If not all requests were processed for whatever reason, the poll file
1458	will still be ready when C<poll_cb> returns, so normally you don't have to	1785	descriptor will still be ready when C<poll_cb> returns, so normally you
1459	do anything special to have it called later.	1786	don't have to do anything special to have it called later.
1460		1787
1461	Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes	1788	Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes
1462	ready, it can be beneficial to call this function from loops which submit	1789	ready, it can be beneficial to call this function from loops which submit
1463	a lot of requests, to make sure the results get processed when they become	1790	a lot of requests, to make sure the results get processed when they become
1464	available and not just when the loop is finished and the event loop takes	1791	available and not just when the loop is finished and the event loop takes
…		…
1473	poll => 'r', async => 1,	1800	poll => 'r', async => 1,
1474	cb => \&IO::AIO::poll_cb);	1801	cb => \&IO::AIO::poll_cb);
1475		1802
1476	=item IO::AIO::poll_wait	1803	=item IO::AIO::poll_wait
1477		1804
1478	If there are any outstanding requests and none of them in the result	1805	Wait until either at least one request is in the result phase or no
1479	phase, wait till the result filehandle becomes ready for reading (simply	1806	requests are outstanding anymore.
1480	does a C<select> on the filehandle. This is useful if you want to	1807
1481	synchronously wait for some requests to finish).	1808	This is useful if you want to synchronously wait for some requests to
		1809	become ready, without actually handling them.
1482		1810
1483	See C<nreqs> for an example.	1811	See C<nreqs> for an example.
1484		1812
1485	=item IO::AIO::poll	1813	=item IO::AIO::poll
1486		1814
…		…
1607		1935
1608	This is a very bad function to use in interactive programs because it	1936	This is a very bad function to use in interactive programs because it
1609	blocks, and a bad way to reduce concurrency because it is inexact: Better	1937	blocks, and a bad way to reduce concurrency because it is inexact: Better
1610	use an C<aio_group> together with a feed callback.	1938	use an C<aio_group> together with a feed callback.
1611		1939
1612	It's main use is in scripts without an event loop - when you want to stat	1940	Its main use is in scripts without an event loop - when you want to stat
1613	a lot of files, you can write somehting like this:	1941	a lot of files, you can write somehting like this:
1614		1942
1615	IO::AIO::max_outstanding 32;	1943	IO::AIO::max_outstanding 32;
1616		1944
1617	for my $path (...) {	1945	for my $path (...) {
…		…
1657		1985
1658	=back	1986	=back
1659		1987
1660	=head3 MISCELLANEOUS FUNCTIONS	1988	=head3 MISCELLANEOUS FUNCTIONS
1661		1989
1662	IO::AIO implements some functions that might be useful, but are not	1990	IO::AIO implements some functions that are useful when you want to use
1663	asynchronous.	1991	some "Advanced I/O" function not available to in Perl, without going the
		1992	"Asynchronous I/O" route. Many of these have an asynchronous C<aio_*>
		1993	counterpart.
1664		1994
1665	=over 4	1995	=over 4
1666		1996
1667	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count	1997	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
1668		1998
…		…
1705	ENOSYS, otherwise the return value of C<mprotect>.	2035	ENOSYS, otherwise the return value of C<mprotect>.
1706		2036
1707	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]	2037	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]
1708		2038
1709	Memory-maps a file (or anonymous memory range) and attaches it to the	2039	Memory-maps a file (or anonymous memory range) and attaches it to the
1710	given C<$scalar>, which will act like a string scalar.	2040	given C<$scalar>, which will act like a string scalar. Returns true on
		2041	success, and false otherwise.
1711		2042
1712	The only operations allowed on the scalar are C<substr>/C<vec> that don't	2043	The only operations allowed on the scalar are C<substr>/C<vec> that don't
1713	change the string length, and most read-only operations such as copying it	2044	change the string length, and most read-only operations such as copying it
1714	or searching it with regexes and so on.	2045	or searching it with regexes and so on.
1715		2046
…		…
1726	filesize.	2057	filesize.
1727		2058
1728	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,	2059	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,
1729	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,	2060	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,
1730		2061
1731	C<$flags> can be a combination of C<IO::AIO::MAP_SHARED> or	2062	C<$flags> can be a combination of
1732	C<IO::AIO::MAP_PRIVATE>, or a number of system-specific flags (when	2063	C<IO::AIO::MAP_SHARED> or
1733	not available, the are defined as 0): C<IO::AIO::MAP_ANONYMOUS>	2064	C<IO::AIO::MAP_PRIVATE>,
		2065	or a number of system-specific flags (when not available, the are C<0>):
1734	(which is set to C<MAP_ANON> if your system only provides this	2066	C<IO::AIO::MAP_ANONYMOUS> (which is set to C<MAP_ANON> if your system only provides this constant),
1735	constant), C<IO::AIO::MAP_HUGETLB>, C<IO::AIO::MAP_LOCKED>,	2067	C<IO::AIO::MAP_HUGETLB>,
1736	C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or	2068	C<IO::AIO::MAP_LOCKED>,
		2069	C<IO::AIO::MAP_NORESERVE>,
		2070	C<IO::AIO::MAP_POPULATE>,
1737	C<IO::AIO::MAP_NONBLOCK>	2071	C<IO::AIO::MAP_NONBLOCK>,
		2072	C<IO::AIO::MAP_FIXED>,
		2073	C<IO::AIO::MAP_GROWSDOWN>,
		2074	C<IO::AIO::MAP_32BIT>,
		2075	C<IO::AIO::MAP_HUGETLB> or
		2076	C<IO::AIO::MAP_STACK>.
1738		2077
1739	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.	2078	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.
1740		2079
1741	C<$offset> is the offset from the start of the file - it generally must be	2080	C<$offset> is the offset from the start of the file - it generally must be
1742	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.	2081	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.
…		…
1767		2106
1768	Calls the C<munlockall> function.	2107	Calls the C<munlockall> function.
1769		2108
1770	On systems that do not implement C<munlockall>, this function returns	2109	On systems that do not implement C<munlockall>, this function returns
1771	ENOSYS, otherwise the return value of C<munlockall>.	2110	ENOSYS, otherwise the return value of C<munlockall>.
		2111
		2112	=item IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags
		2113
		2114	Calls the GNU/Linux C<splice(2)> syscall, if available. If C<$r_off> or
		2115	C<$w_off> are C<undef>, then C<NULL> is passed for these, otherwise they
		2116	should be the file offset.
		2117
		2118	C<$r_fh> and C<$w_fh> should not refer to the same file, as splice might
		2119	silently corrupt the data in this case.
		2120
		2121	The following symbol flag values are available: C<IO::AIO::SPLICE_F_MOVE>,
		2122	C<IO::AIO::SPLICE_F_NONBLOCK>, C<IO::AIO::SPLICE_F_MORE> and
		2123	C<IO::AIO::SPLICE_F_GIFT>.
		2124
		2125	See the C<splice(2)> manpage for details.
		2126
		2127	=item IO::AIO::tee $r_fh, $w_fh, $length, $flags
		2128
		2129	Calls the GNU/Linux C<tee(2)> syscall, see its manpage and the
		2130	description for C<IO::AIO::splice> above for details.
		2131
		2132	=item $actual_size = IO::AIO::pipesize $r_fh[, $new_size]
		2133
		2134	Attempts to query or change the pipe buffer size. Obviously works only
		2135	on pipes, and currently works only on GNU/Linux systems, and fails with
		2136	C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer
		2137	size on other systems, drop me a note.
		2138
		2139	=item ($rfh, $wfh) = IO::AIO::pipe2 [$flags]
		2140
		2141	This is a direct interface to the Linux L<pipe2(2)> system call. If
		2142	C<$flags> is missing or C<0>, then this should be the same as a call to
		2143	perl's built-in C<pipe> function and create a new pipe, and works on
		2144	systems that lack the pipe2 syscall. On win32, this case invokes C<_pipe
		2145	(..., 4096, O_BINARY)>.
		2146
		2147	If C<$flags> is non-zero, it tries to invoke the pipe2 system call with
		2148	the given flags (Linux 2.6.27, glibc 2.9).
		2149
		2150	On success, the read and write file handles are returned.
		2151
		2152	On error, nothing will be returned. If the pipe2 syscall is missing and
		2153	C<$flags> is non-zero, fails with C<ENOSYS>.
		2154
		2155	Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the
		2156	time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and
		2157	C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported.
1772		2158
1773	=back	2159	=back
1774		2160
1775	=cut	2161	=cut
1776		2162

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Comparing IO-AIO/AIO.pm (file contents): Revision 1.208 by root, Mon Sep 26 20:19:08 2011 UTC vs. Revision 1.256 by root, Thu Jun 25 15:47:01 2015 UTC

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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.208 by root, Mon Sep 26 20:19:08 2011 UTC vs.
Revision 1.256 by root, Thu Jun 25 15:47:01 2015 UTC