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

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.206 by root, Sun Jul 24 03:32:51 2011 UTC vs.
Revision 1.248 by root, Sun Jul 27 22:10:53 2014 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 = 4.31;
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
		184	aio_wd);
185		185
186	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));	186	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));
187	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush	187	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush
188	min_parallel max_parallel max_idle idle_timeout	188	min_parallel max_parallel max_idle idle_timeout
189	nreqs nready npending nthreads	189	nreqs nready npending nthreads
…		…
201		201
202	=head1 FUNCTIONS	202	=head1 FUNCTIONS
203		203
204	=head2 QUICK OVERVIEW	204	=head2 QUICK OVERVIEW
205		205
206	This section simply lists the prototypes of the most important functions	206	This section simply lists the prototypes most of the functions for
207	for quick reference. See the following sections for function-by-function	207	quick reference. See the following sections for function-by-function
208	documentation.	208	documentation.
209		209
		210	aio_wd $pathname, $callback->($wd)
210	aio_open $pathname, $flags, $mode, $callback->($fh)	211	aio_open $pathname, $flags, $mode, $callback->($fh)
211	aio_close $fh, $callback->($status)	212	aio_close $fh, $callback->($status)
		213	aio_seek $fh,$offset,$whence, $callback->($offs)
212	aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	214	aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
213	aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	215	aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
214	aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)	216	aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
215	aio_readahead $fh,$offset,$length, $callback->($retval)	217	aio_readahead $fh,$offset,$length, $callback->($retval)
216	aio_stat $fh_or_path, $callback->($status)	218	aio_stat $fh_or_path, $callback->($status)
217	aio_lstat $fh, $callback->($status)	219	aio_lstat $fh, $callback->($status)
218	aio_statvfs $fh_or_path, $callback->($statvfs)	220	aio_statvfs $fh_or_path, $callback->($statvfs)
219	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	221	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
220	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)
221	aio_truncate $fh_or_path, $offset, $callback->($status)	224	aio_truncate $fh_or_path, $offset, $callback->($status)
222	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)
223	aio_unlink $pathname, $callback->($status)	227	aio_unlink $pathname, $callback->($status)
224	aio_mknod $path, $mode, $dev, $callback->($status)	228	aio_mknod $pathname, $mode, $dev, $callback->($status)
225	aio_link $srcpath, $dstpath, $callback->($status)	229	aio_link $srcpath, $dstpath, $callback->($status)
226	aio_symlink $srcpath, $dstpath, $callback->($status)	230	aio_symlink $srcpath, $dstpath, $callback->($status)
227	aio_readlink $path, $callback->($link)	231	aio_readlink $pathname, $callback->($link)
228	aio_realpath $path, $callback->($link)	232	aio_realpath $pathname, $callback->($link)
229	aio_rename $srcpath, $dstpath, $callback->($status)	233	aio_rename $srcpath, $dstpath, $callback->($status)
230	aio_mkdir $pathname, $mode, $callback->($status)	234	aio_mkdir $pathname, $mode, $callback->($status)
231	aio_rmdir $pathname, $callback->($status)	235	aio_rmdir $pathname, $callback->($status)
232	aio_readdir $pathname, $callback->($entries)	236	aio_readdir $pathname, $callback->($entries)
233	aio_readdirx $pathname, $flags, $callback->($entries, $flags)	237	aio_readdirx $pathname, $flags, $callback->($entries, $flags)
234	IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST	238	IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST
235	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)
236	aio_load $path, $data, $callback->($status)	241	aio_load $pathname, $data, $callback->($status)
237	aio_copy $srcpath, $dstpath, $callback->($status)	242	aio_copy $srcpath, $dstpath, $callback->($status)
238	aio_move $srcpath, $dstpath, $callback->($status)	243	aio_move $srcpath, $dstpath, $callback->($status)
239	aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
240	aio_rmtree $path, $callback->($status)	244	aio_rmtree $pathname, $callback->($status)
241	aio_sync $callback->($status)	245	aio_sync $callback->($status)
242	aio_syncfs $fh, $callback->($status)	246	aio_syncfs $fh, $callback->($status)
243	aio_fsync $fh, $callback->($status)	247	aio_fsync $fh, $callback->($status)
244	aio_fdatasync $fh, $callback->($status)	248	aio_fdatasync $fh, $callback->($status)
245	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)	249	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
246	aio_pathsync $path, $callback->($status)	250	aio_pathsync $pathname, $callback->($status)
247	aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	251	aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
248	aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	252	aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
249	aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)	253	aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
250	aio_mlockall $flags, $callback->($status)	254	aio_mlockall $flags, $callback->($status)
251	aio_group $callback->(...)	255	aio_group $callback->(...)
…		…
269	IO::AIO::nready	273	IO::AIO::nready
270	IO::AIO::npending	274	IO::AIO::npending
271		275
272	IO::AIO::sendfile $ofh, $ifh, $offset, $count	276	IO::AIO::sendfile $ofh, $ifh, $offset, $count
273	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
274	IO::AIO::madvise $scalar, $offset, $length, $advice	280	IO::AIO::madvise $scalar, $offset, $length, $advice
275	IO::AIO::mprotect $scalar, $offset, $length, $protect	281	IO::AIO::mprotect $scalar, $offset, $length, $protect
276	IO::AIO::munlock $scalar, $offset = 0, $length = undef	282	IO::AIO::munlock $scalar, $offset = 0, $length = undef
277	IO::AIO::munlockall	283	IO::AIO::munlockall
278		284
279	=head2 AIO REQUEST FUNCTIONS	285	=head2 API NOTES
280		286
281	All the C<aio_*> calls are more or less thin wrappers around the syscall	287	All the C<aio_*> calls are more or less thin wrappers around the syscall
282	with the same name (sans C<aio_>). The arguments are similar or identical,	288	with the same name (sans C<aio_>). The arguments are similar or identical,
283	and they all accept an additional (and optional) C<$callback> argument	289	and they all accept an additional (and optional) C<$callback> argument
284	which must be a code reference. This code reference will get called with	290	which must be a code reference. This code reference will be called after
285	the syscall return code (e.g. most syscalls return C<-1> on error, unlike	291	the syscall has been executed in an asynchronous fashion. The results
286	perl, which usually delivers "false") as its sole argument after the given	292	of the request will be passed as arguments to the callback (and, if an
287	syscall has been executed asynchronously.	293	error occured, in C<$!>) - 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>.
288		299
289	All functions expecting a filehandle keep a copy of the filehandle	300	All functions expecting a filehandle keep a copy of the filehandle
290	internally until the request has finished.	301	internally until the request has finished.
291		302
292	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
293	further manipulation of those requests while they are in-flight.	304	further manipulation of those requests while they are in-flight.
294		305
295	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
296	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
297	request is being executed, the current working directory could have	308	current working directory could have changed. Alternatively, you can
298	changed. Alternatively, you can make sure that you never change the	309	make sure that you never change the current working directory anywhere
299	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
300	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.
301		314
302	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
303	in filenames you got from outside (command line, readdir etc.) without	316	in filenames you got from outside (command line, readdir etc.) without
304	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
305	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
306	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
307	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.
308		322
309	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
310	handles correctly whether it is set or not.	324	handles correctly whether it is set or not.
		325
		326	=head2 AIO REQUEST FUNCTIONS
311		327
312	=over 4	328	=over 4
313		329
314	=item $prev_pri = aioreq_pri [$pri]	330	=item $prev_pri = aioreq_pri [$pri]
315		331
…		…
345		361
346		362
347	=item aio_open $pathname, $flags, $mode, $callback->($fh)	363	=item aio_open $pathname, $flags, $mode, $callback->($fh)
348		364
349	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
350	created filehandle for the file.	366	created filehandle for the file (or C<undef> in case of an error).
351		367
352	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,
353	for an explanation.	369	for an explanation.
354		370
355	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
…		…
397		413
398	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
399	free for reuse until the perl filehandle is closed.	415	free for reuse until the perl filehandle is closed.
400		416
401	=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".
402		438
403	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	439	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
404		440
405	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	441	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
406		442
…		…
566	namemax => 255,	602	namemax => 255,
567	frsize => 1024,	603	frsize => 1024,
568	fsid => 1810	604	fsid => 1810
569	}	605	}
570		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
571		688
572	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	689	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
573		690
574	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
575	and $mtime being undef). Fractional times are supported if the underlying	692	and $mtime being undef). Fractional times are supported if the underlying
…		…
603	=item aio_truncate $fh_or_path, $offset, $callback->($status)	720	=item aio_truncate $fh_or_path, $offset, $callback->($status)
604		721
605	Works like truncate(2) or ftruncate(2).	722	Works like truncate(2) or ftruncate(2).
606		723
607		724
		725	=item aio_allocate $fh, $mode, $offset, $len, $callback->($status)
		726
		727	Allocates or freed disk space according to the C<$mode> argument. See the
		728	linux C<fallocate> docuemntation for details.
		729
		730	C<$mode> can currently be C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE>
		731	to allocate space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE \|
		732	IO::AIO::FALLOC_FL_KEEP_SIZE>, to deallocate a file range.
		733
		734	The file system block size used by C<fallocate> is presumably the
		735	C<f_bsize> returned by C<statvfs>.
		736
		737	If C<fallocate> isn't available or cannot be emulated (currently no
		738	emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>.
		739
		740
608	=item aio_chmod $fh_or_path, $mode, $callback->($status)	741	=item aio_chmod $fh_or_path, $mode, $callback->($status)
609		742
610	Works like perl's C<chmod> function.	743	Works like perl's C<chmod> function.
611		744
612		745
…		…
614		747
615	Asynchronously unlink (delete) a file and call the callback with the	748	Asynchronously unlink (delete) a file and call the callback with the
616	result code.	749	result code.
617		750
618		751
619	=item aio_mknod $path, $mode, $dev, $callback->($status)	752	=item aio_mknod $pathname, $mode, $dev, $callback->($status)
620		753
621	[EXPERIMENTAL]	754	[EXPERIMENTAL]
622		755
623	Asynchronously create a device node (or fifo). See mknod(2).	756	Asynchronously create a device node (or fifo). See mknod(2).
624		757
625	The only (POSIX-) portable way of calling this function is:	758	The only (POSIX-) portable way of calling this function is:
626		759
627	aio_mknod $path, IO::AIO::S_IFIFO \| $mode, 0, sub { ...	760	aio_mknod $pathname, IO::AIO::S_IFIFO \| $mode, 0, sub { ...
628		761
629	See C<aio_stat> for info about some potentially helpful extra constants	762	See C<aio_stat> for info about some potentially helpful extra constants
630	and functions.	763	and functions.
631		764
632	=item aio_link $srcpath, $dstpath, $callback->($status)	765	=item aio_link $srcpath, $dstpath, $callback->($status)
…		…
639		772
640	Asynchronously create a new symbolic link to the existing object at C<$srcpath> at	773	Asynchronously create a new symbolic link to the existing object at C<$srcpath> at
641	the path C<$dstpath> and call the callback with the result code.	774	the path C<$dstpath> and call the callback with the result code.
642		775
643		776
644	=item aio_readlink $path, $callback->($link)	777	=item aio_readlink $pathname, $callback->($link)
645		778
646	Asynchronously read the symlink specified by C<$path> and pass it to	779	Asynchronously read the symlink specified by C<$path> and pass it to
647	the callback. If an error occurs, nothing or undef gets passed to the	780	the callback. If an error occurs, nothing or undef gets passed to the
648	callback.	781	callback.
649		782
650		783
651	=item aio_realpath $path, $callback->($path)	784	=item aio_realpath $pathname, $callback->($path)
652		785
653	Asynchronously make the path absolute and resolve any symlinks in	786	Asynchronously make the path absolute and resolve any symlinks in
654	C<$path>. The resulting path only consists of directories (Same as	787	C<$path>. The resulting path only consists of directories (same as
655	L<Cwd::realpath>).	788	L<Cwd::realpath>).
656		789
657	This request can be used to get the absolute path of the current working	790	This request can be used to get the absolute path of the current working
658	directory by passing it a path of F<.> (a single dot).	791	directory by passing it a path of F<.> (a single dot).
659		792
660		793
661	=item aio_rename $srcpath, $dstpath, $callback->($status)	794	=item aio_rename $srcpath, $dstpath, $callback->($status)
662		795
663	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as	796	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as
664	rename(2) and call the callback with the result code.	797	rename(2) and call the callback with the result code.
		798
		799	On systems that support the AIO::WD working directory abstraction
		800	natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead
		801	of failing, C<rename> is called on the absolute path of C<$wd>.
665		802
666		803
667	=item aio_mkdir $pathname, $mode, $callback->($status)	804	=item aio_mkdir $pathname, $mode, $callback->($status)
668		805
669	Asynchronously mkdir (create) a directory and call the callback with	806	Asynchronously mkdir (create) a directory and call the callback with
…		…
674	=item aio_rmdir $pathname, $callback->($status)	811	=item aio_rmdir $pathname, $callback->($status)
675		812
676	Asynchronously rmdir (delete) a directory and call the callback with the	813	Asynchronously rmdir (delete) a directory and call the callback with the
677	result code.	814	result code.
678		815
		816	On systems that support the AIO::WD working directory abstraction
		817	natively, the case C<[$wd, "."]> is specialcased - instead of failing,
		818	C<rmdir> is called on the absolute path of C<$wd>.
		819
679		820
680	=item aio_readdir $pathname, $callback->($entries)	821	=item aio_readdir $pathname, $callback->($entries)
681		822
682	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire	823	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire
683	directory (i.e. opendir + readdir + closedir). The entries will not be	824	directory (i.e. opendir + readdir + closedir). The entries will not be
…		…
687	array-ref with the filenames.	828	array-ref with the filenames.
688		829
689		830
690	=item aio_readdirx $pathname, $flags, $callback->($entries, $flags)	831	=item aio_readdirx $pathname, $flags, $callback->($entries, $flags)
691		832
692	Quite similar to C<aio_readdir>, but the C<$flags> argument allows to tune	833	Quite similar to C<aio_readdir>, but the C<$flags> argument allows one to
693	behaviour and output format. In case of an error, C<$entries> will be	834	tune behaviour and output format. In case of an error, C<$entries> will be
694	C<undef>.	835	C<undef>.
695		836
696	The flags are a combination of the following constants, ORed together (the	837	The flags are a combination of the following constants, ORed together (the
697	flags will also be passed to the callback, possibly modified):	838	flags will also be passed to the callback, possibly modified):
698		839
…		…
745		886
746	=item IO::AIO::READDIR_FOUND_UNKNOWN	887	=item IO::AIO::READDIR_FOUND_UNKNOWN
747		888
748	This flag should not be set when calling C<aio_readdirx>. Instead, it	889	This flag should not be set when calling C<aio_readdirx>. Instead, it
749	is being set by C<aio_readdirx>, when any of the C<$type>'s found were	890	is being set by C<aio_readdirx>, when any of the C<$type>'s found were
750	C<IO::AIO::DT_UNKNOWN>. The absense of this flag therefore indicates that all	891	C<IO::AIO::DT_UNKNOWN>. The absence of this flag therefore indicates that all
751	C<$type>'s are known, which can be used to speed up some algorithms.	892	C<$type>'s are known, which can be used to speed up some algorithms.
752		893
753	=back	894	=back
754		895
755		896
756	=item aio_load $path, $data, $callback->($status)	897	=item aio_load $pathname, $data, $callback->($status)
757		898
758	This is a composite request that tries to fully load the given file into	899	This is a composite request that tries to fully load the given file into
759	memory. Status is the same as with aio_read.	900	memory. Status is the same as with aio_read.
760		901
761	=cut	902	=cut
…		…
896	};	1037	};
897		1038
898	$grp	1039	$grp
899	}	1040	}
900		1041
901	=item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)	1042	=item aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
902		1043
903	Scans a directory (similar to C<aio_readdir>) but additionally tries to	1044	Scans a directory (similar to C<aio_readdir>) but additionally tries to
904	efficiently separate the entries of directory C<$path> into two sets of	1045	efficiently separate the entries of directory C<$path> into two sets of
905	names, directories you can recurse into (directories), and ones you cannot	1046	names, directories you can recurse into (directories), and ones you cannot
906	recurse into (everything else, including symlinks to directories).	1047	recurse into (everything else, including symlinks to directories).
…		…
937	Then entries will be sorted into likely directories a non-initial dot	1078	Then entries will be sorted into likely directories a non-initial dot
938	currently) and likely non-directories (see C<aio_readdirx>). Then every	1079	currently) and likely non-directories (see C<aio_readdirx>). Then every
939	entry plus an appended C</.> will be C<stat>'ed, likely directories first,	1080	entry plus an appended C</.> will be C<stat>'ed, likely directories first,
940	in order of their inode numbers. If that succeeds, it assumes that the	1081	in order of their inode numbers. If that succeeds, it assumes that the
941	entry is a directory or a symlink to directory (which will be checked	1082	entry is a directory or a symlink to directory (which will be checked
942	seperately). This is often faster than stat'ing the entry itself because	1083	separately). This is often faster than stat'ing the entry itself because
943	filesystems might detect the type of the entry without reading the inode	1084	filesystems might detect the type of the entry without reading the inode
944	data (e.g. ext2fs filetype feature), even on systems that cannot return	1085	data (e.g. ext2fs filetype feature), even on systems that cannot return
945	the filetype information on readdir.	1086	the filetype information on readdir.
946		1087
947	If the known number of directories (link count - 2) has been reached, the	1088	If the known number of directories (link count - 2) has been reached, the
…		…
963		1104
964	my $grp = aio_group $cb;	1105	my $grp = aio_group $cb;
965		1106
966	$maxreq = 4 if $maxreq <= 0;	1107	$maxreq = 4 if $maxreq <= 0;
967		1108
968	# stat once	1109	# get a wd object
969	aioreq_pri $pri;	1110	aioreq_pri $pri;
970	add $grp aio_stat $path, sub {	1111	add $grp aio_wd $path, sub {
		1112	$_[0]
971	return $grp->result () if $_[0];	1113	or return $grp->result ();
972	my $now = time;
973	my $hash1 = join ":", (stat _)[0,1,3,7,9];
974		1114
975	# read the directory entries	1115	my $wd = [shift, "."];
		1116
		1117	# stat once
976	aioreq_pri $pri;	1118	aioreq_pri $pri;
977	add $grp aio_readdirx $path, READDIR_DIRS_FIRST, sub {	1119	add $grp aio_stat $wd, sub {
978	my $entries = shift
979	or return $grp->result ();	1120	return $grp->result () if $_[0];
		1121	my $now = time;
		1122	my $hash1 = join ":", (stat _)[0,1,3,7,9];
980		1123
981	# stat the dir another time	1124	# read the directory entries
982	aioreq_pri $pri;	1125	aioreq_pri $pri;
		1126	add $grp aio_readdirx $wd, READDIR_DIRS_FIRST, sub {
		1127	my $entries = shift
		1128	or return $grp->result ();
		1129
		1130	# stat the dir another time
		1131	aioreq_pri $pri;
983	add $grp aio_stat $path, sub {	1132	add $grp aio_stat $wd, sub {
984	my $hash2 = join ":", (stat _)[0,1,3,7,9];	1133	my $hash2 = join ":", (stat _)[0,1,3,7,9];
985		1134
986	my $ndirs;	1135	my $ndirs;
987		1136
988	# take the slow route if anything looks fishy	1137	# take the slow route if anything looks fishy
989	if ($hash1 ne $hash2 or (stat _)[9] == $now) {	1138	if ($hash1 ne $hash2 or (stat _)[9] == $now) {
990	$ndirs = -1;	1139	$ndirs = -1;
991	} else {	1140	} else {
992	# if nlink == 2, we are finished	1141	# if nlink == 2, we are finished
993	# for non-posix-fs's, we rely on nlink < 2	1142	# for non-posix-fs's, we rely on nlink < 2
994	$ndirs = (stat _)[3] - 2	1143	$ndirs = (stat _)[3] - 2
995	or return $grp->result ([], $entries);	1144	or return $grp->result ([], $entries);
996	}	1145	}
997		1146
998	my (@dirs, @nondirs);	1147	my (@dirs, @nondirs);
999		1148
1000	my $statgrp = add $grp aio_group sub {	1149	my $statgrp = add $grp aio_group sub {
1001	$grp->result (\@dirs, \@nondirs);	1150	$grp->result (\@dirs, \@nondirs);
1002	};	1151	};
1003		1152
1004	limit $statgrp $maxreq;	1153	limit $statgrp $maxreq;
1005	feed $statgrp sub {	1154	feed $statgrp sub {
1006	return unless @$entries;	1155	return unless @$entries;
1007	my $entry = shift @$entries;	1156	my $entry = shift @$entries;
1008		1157
1009	aioreq_pri $pri;	1158	aioreq_pri $pri;
		1159	$wd->[1] = "$entry/.";
1010	add $statgrp aio_stat "$path/$entry/.", sub {	1160	add $statgrp aio_stat $wd, sub {
1011	if ($_[0] < 0) {	1161	if ($_[0] < 0) {
1012	push @nondirs, $entry;	1162	push @nondirs, $entry;
1013	} else {	1163	} else {
1014	# need to check for real directory	1164	# need to check for real directory
1015	aioreq_pri $pri;	1165	aioreq_pri $pri;
		1166	$wd->[1] = $entry;
1016	add $statgrp aio_lstat "$path/$entry", sub {	1167	add $statgrp aio_lstat $wd, sub {
1017	if (-d _) {	1168	if (-d _) {
1018	push @dirs, $entry;	1169	push @dirs, $entry;
1019		1170
1020	unless (--$ndirs) {	1171	unless (--$ndirs) {
1021	push @nondirs, @$entries;	1172	push @nondirs, @$entries;
1022	feed $statgrp;	1173	feed $statgrp;
		1174	}
		1175	} else {
		1176	push @nondirs, $entry;
1023	}	1177	}
1024	} else {
1025	push @nondirs, $entry;
1026	}	1178	}
1027	}	1179	}
1028	}	1180	};
1029	};	1181	};
1030	};	1182	};
1031	};	1183	};
1032	};	1184	};
1033	};	1185	};
1034		1186
1035	$grp	1187	$grp
1036	}	1188	}
1037		1189
1038	=item aio_rmtree $path, $callback->($status)	1190	=item aio_rmtree $pathname, $callback->($status)
1039		1191
1040	Delete a directory tree starting (and including) C<$path>, return the	1192	Delete a directory tree starting (and including) C<$path>, return the
1041	status of the final C<rmdir> only. This is a composite request that	1193	status of the final C<rmdir> only. This is a composite request that
1042	uses C<aio_scandir> to recurse into and rmdir directories, and unlink	1194	uses C<aio_scandir> to recurse into and rmdir directories, and unlink
1043	everything else.	1195	everything else.
1044		1196
1045	=cut	1197	=cut
1046		1198
…		…
1104	C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>,	1256	C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>,
1105	C<IO::AIO::SYNC_FILE_RANGE_WRITE> and	1257	C<IO::AIO::SYNC_FILE_RANGE_WRITE> and
1106	C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range	1258	C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range
1107	manpage for details.	1259	manpage for details.
1108		1260
1109	=item aio_pathsync $path, $callback->($status)	1261	=item aio_pathsync $pathname, $callback->($status)
1110		1262
1111	This request tries to open, fsync and close the given path. This is a	1263	This request tries to open, fsync and close the given path. This is a
1112	composite request intended to sync directories after directory operations	1264	composite request intended to sync directories after directory operations
1113	(E.g. rename). This might not work on all operating systems or have any	1265	(E.g. rename). This might not work on all operating systems or have any
1114	specific effect, but usually it makes sure that directory changes get	1266	specific effect, but usually it makes sure that directory changes get
…		…
1166		1318
1167	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1319	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
1168	scalars.	1320	scalars.
1169		1321
1170	It touches (reads or writes) all memory pages in the specified	1322	It touches (reads or writes) all memory pages in the specified
1171	range inside the scalar. All caveats and parameters are the same	1323	range inside the scalar. All caveats and parameters are the same
1172	as for C<aio_msync>, above, except for flags, which must be either	1324	as for C<aio_msync>, above, except for flags, which must be either
1173	C<0> (which reads all pages and ensures they are instantiated) or	1325	C<0> (which reads all pages and ensures they are instantiated) or
1174	C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and	1326	C<IO::AIO::MT_MODIFY>, which modifies the memory pages (by reading and
1175	writing an octet from it, which dirties the page).	1327	writing an octet from it, which dirties the page).
1176		1328
1177	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)	1329	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
1178		1330
1179	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1331	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
…		…
1210	documented under L<MISCELLANEOUS FUNCTIONS>.	1362	documented under L<MISCELLANEOUS FUNCTIONS>.
1211		1363
1212	Example: asynchronously lock all current and future pages into memory.	1364	Example: asynchronously lock all current and future pages into memory.
1213		1365
1214	aio_mlockall IO::AIO::MCL_FUTURE;	1366	aio_mlockall IO::AIO::MCL_FUTURE;
		1367
		1368	=item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
		1369
		1370	Queries the extents of the given file (by calling the Linux C<FIEMAP>
		1371	ioctl, see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If
		1372	the ioctl is not available on your OS, then this request will fail with
		1373	C<ENOSYS>.
		1374
		1375	C<$start> is the starting offset to query extents for, C<$length> is the
		1376	size of the range to query - if it is C<undef>, then the whole file will
		1377	be queried.
		1378
		1379	C<$flags> is a combination of flags (C<IO::AIO::FIEMAP_FLAG_SYNC> or
		1380	C<IO::AIO::FIEMAP_FLAG_XATTR> - C<IO::AIO::FIEMAP_FLAGS_COMPAT> is also
		1381	exported), and is normally C<0> or C<IO::AIO::FIEMAP_FLAG_SYNC> to query
		1382	the data portion.
		1383
		1384	C<$count> is the maximum number of extent records to return. If it is
		1385	C<undef>, then IO::AIO queries all extents of the range. As a very special
		1386	case, if it is C<0>, then the callback receives the number of extents
		1387	instead of the extents themselves (which is unreliable, see below).
		1388
		1389	If an error occurs, the callback receives no arguments. The special
		1390	C<errno> value C<IO::AIO::EBADR> is available to test for flag errors.
		1391
		1392	Otherwise, the callback receives an array reference with extent
		1393	structures. Each extent structure is an array reference itself, with the
		1394	following members:
		1395
		1396	[$logical, $physical, $length, $flags]
		1397
		1398	Flags is any combination of the following flag values (typically either C<0>
		1399	or C<IO::AIO::FIEMAP_EXTENT_LAST> (1)):
		1400
		1401	C<IO::AIO::FIEMAP_EXTENT_LAST>, C<IO::AIO::FIEMAP_EXTENT_UNKNOWN>,
		1402	C<IO::AIO::FIEMAP_EXTENT_DELALLOC>, C<IO::AIO::FIEMAP_EXTENT_ENCODED>,
		1403	C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>,
		1404	C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>,
		1405	C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or
		1406	C<IO::AIO::FIEMAP_EXTENT_SHARED>.
		1407
		1408	At the time of this writing (Linux 3.2), this requets is unreliable unless
		1409	C<$count> is C<undef>, as the kernel has all sorts of bugs preventing
		1410	it to return all extents of a range for files with large number of
		1411	extents. The code works around all these issues if C<$count> is undef.
1215		1412
1216	=item aio_group $callback->(...)	1413	=item aio_group $callback->(...)
1217		1414
1218	This is a very special aio request: Instead of doing something, it is a	1415	This is a very special aio request: Instead of doing something, it is a
1219	container for other aio requests, which is useful if you want to bundle	1416	container for other aio requests, which is useful if you want to bundle
…		…
1256	like sleep and file handle readable/writable, the overhead this creates is	1453	like sleep and file handle readable/writable, the overhead this creates is
1257	immense (it blocks a thread for a long time) so do not use this function	1454	immense (it blocks a thread for a long time) so do not use this function
1258	except to put your application under artificial I/O pressure.	1455	except to put your application under artificial I/O pressure.
1259		1456
1260	=back	1457	=back
		1458
		1459
		1460	=head2 IO::AIO::WD - multiple working directories
		1461
		1462	Your process only has one current working directory, which is used by all
		1463	threads. This makes it hard to use relative paths (some other component
		1464	could call C<chdir> at any time, and it is hard to control when the path
		1465	will be used by IO::AIO).
		1466
		1467	One solution for this is to always use absolute paths. This usually works,
		1468	but can be quite slow (the kernel has to walk the whole path on every
		1469	access), and can also be a hassle to implement.
		1470
		1471	Newer POSIX systems have a number of functions (openat, fdopendir,
		1472	futimensat and so on) that make it possible to specify working directories
		1473	per operation.
		1474
		1475	For portability, and because the clowns who "designed", or shall I write,
		1476	perpetrated this new interface were obviously half-drunk, this abstraction
		1477	cannot be perfect, though.
		1478
		1479	IO::AIO allows you to convert directory paths into a so-called IO::AIO::WD
		1480	object. This object stores the canonicalised, absolute version of the
		1481	path, and on systems that allow it, also a directory file descriptor.
		1482
		1483	Everywhere where a pathname is accepted by IO::AIO (e.g. in C<aio_stat>
		1484	or C<aio_unlink>), one can specify an array reference with an IO::AIO::WD
		1485	object and a pathname instead (or the IO::AIO::WD object alone, which
		1486	gets interpreted as C<[$wd, "."]>). If the pathname is absolute, the
		1487	IO::AIO::WD object is ignored, otherwise the pathname is resolved relative
		1488	to that IO::AIO::WD object.
		1489
		1490	For example, to get a wd object for F</etc> and then stat F<passwd>
		1491	inside, you would write:
		1492
		1493	aio_wd "/etc", sub {
		1494	my $etcdir = shift;
		1495
		1496	# although $etcdir can be undef on error, there is generally no reason
		1497	# to check for errors here, as aio_stat will fail with ENOENT
		1498	# when $etcdir is undef.
		1499
		1500	aio_stat [$etcdir, "passwd"], sub {
		1501	# yay
		1502	};
		1503	};
		1504
		1505	That C<aio_wd> is a request and not a normal function shows that creating
		1506	an IO::AIO::WD object is itself a potentially blocking operation, which is
		1507	why it is done asynchronously.
		1508
		1509	To stat the directory obtained with C<aio_wd> above, one could write
		1510	either of the following three request calls:
		1511
		1512	aio_lstat "/etc" , sub { ... # pathname as normal string
		1513	aio_lstat [$wd, "."], sub { ... # "." relative to $wd (i.e. $wd itself)
		1514	aio_lstat $wd , sub { ... # shorthand for the previous
		1515
		1516	As with normal pathnames, IO::AIO keeps a copy of the working directory
		1517	object and the pathname string, so you could write the following without
		1518	causing any issues due to C<$path> getting reused:
		1519
		1520	my $path = [$wd, undef];
		1521
		1522	for my $name (qw(abc def ghi)) {
		1523	$path->[1] = $name;
		1524	aio_stat $path, sub {
		1525	# ...
		1526	};
		1527	}
		1528
		1529	There are some caveats: when directories get renamed (or deleted), the
		1530	pathname string doesn't change, so will point to the new directory (or
		1531	nowhere at all), while the directory fd, if available on the system,
		1532	will still point to the original directory. Most functions accepting a
		1533	pathname will use the directory fd on newer systems, and the string on
		1534	older systems. Some functions (such as realpath) will always rely on the
		1535	string form of the pathname.
		1536
		1537	So this functionality is mainly useful to get some protection against
		1538	C<chdir>, to easily get an absolute path out of a relative path for future
		1539	reference, and to speed up doing many operations in the same directory
		1540	(e.g. when stat'ing all files in a directory).
		1541
		1542	The following functions implement this working directory abstraction:
		1543
		1544	=over 4
		1545
		1546	=item aio_wd $pathname, $callback->($wd)
		1547
		1548	Asynchonously canonicalise the given pathname and convert it to an
		1549	IO::AIO::WD object representing it. If possible and supported on the
		1550	system, also open a directory fd to speed up pathname resolution relative
		1551	to this working directory.
		1552
		1553	If something goes wrong, then C<undef> is passwd to the callback instead
		1554	of a working directory object and C<$!> is set appropriately. Since
		1555	passing C<undef> as working directory component of a pathname fails the
		1556	request with C<ENOENT>, there is often no need for error checking in the
		1557	C<aio_wd> callback, as future requests using the value will fail in the
		1558	expected way.
		1559
		1560	=item IO::AIO::CWD
		1561
		1562	This is a compiletime constant (object) that represents the process
		1563	current working directory.
		1564
		1565	Specifying this object as working directory object for a pathname is as if
		1566	the pathname would be specified directly, without a directory object. For
		1567	example, these calls are functionally identical:
		1568
		1569	aio_stat "somefile", sub { ... };
		1570	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };
		1571
		1572	=back
		1573
		1574	To recover the path associated with an IO::AIO::WD object, you can use
		1575	C<aio_realpath>:
		1576
		1577	aio_realpath $wd, sub {
		1578	warn "path is $_[0]\n";
		1579	};
		1580
		1581	Currently, C<aio_statvfs> always, and C<aio_rename> and C<aio_rmdir>
		1582	sometimes, fall back to using an absolue path.
1261		1583
1262	=head2 IO::AIO::REQ CLASS	1584	=head2 IO::AIO::REQ CLASS
1263		1585
1264	All non-aggregate C<aio_*> functions return an object of this class when	1586	All non-aggregate C<aio_*> functions return an object of this class when
1265	called in non-void context.	1587	called in non-void context.
…		…
1383		1705
1384	Sets a feeder/generator on this group: every group can have an attached	1706	Sets a feeder/generator on this group: every group can have an attached
1385	generator that generates requests if idle. The idea behind this is that,	1707	generator that generates requests if idle. The idea behind this is that,
1386	although you could just queue as many requests as you want in a group,	1708	although you could just queue as many requests as you want in a group,
1387	this might starve other requests for a potentially long time. For example,	1709	this might starve other requests for a potentially long time. For example,
1388	C<aio_scandir> might generate hundreds of thousands C<aio_stat> requests,	1710	C<aio_scandir> might generate hundreds of thousands of C<aio_stat>
1389	delaying any later requests for a long time.	1711	requests, delaying any later requests for a long time.
1390		1712
1391	To avoid this, and allow incremental generation of requests, you can	1713	To avoid this, and allow incremental generation of requests, you can
1392	instead a group and set a feeder on it that generates those requests. The	1714	instead a group and set a feeder on it that generates those requests. The
1393	feed callback will be called whenever there are few enough (see C<limit>,	1715	feed callback will be called whenever there are few enough (see C<limit>,
1394	below) requests active in the group itself and is expected to queue more	1716	below) requests active in the group itself and is expected to queue more
…		…
1443		1765
1444	See C<poll_cb> for an example.	1766	See C<poll_cb> for an example.
1445		1767
1446	=item IO::AIO::poll_cb	1768	=item IO::AIO::poll_cb
1447		1769
1448	Process some outstanding events on the result pipe. You have to call	1770	Process some requests that have reached the result phase (i.e. they have
		1771	been executed but the results are not yet reported). You have to call
		1772	this "regularly" to finish outstanding requests.
		1773
1449	this regularly. Returns C<0> if all events could be processed (or there	1774	Returns C<0> if all events could be processed (or there were no
1450	were no events to process), or C<-1> if it returned earlier for whatever	1775	events to process), or C<-1> if it returned earlier for whatever
1451	reason. Returns immediately when no events are outstanding. The amount of	1776	reason. Returns immediately when no events are outstanding. The amount
1452	events processed depends on the settings of C<IO::AIO::max_poll_req> and	1777	of events processed depends on the settings of C<IO::AIO::max_poll_req>,
1453	C<IO::AIO::max_poll_time>.	1778	C<IO::AIO::max_poll_time> and C<IO::AIO::max_outstanding>.
1454		1779
1455	If not all requests were processed for whatever reason, the filehandle	1780	If not all requests were processed for whatever reason, the poll file
1456	will still be ready when C<poll_cb> returns, so normally you don't have to	1781	descriptor will still be ready when C<poll_cb> returns, so normally you
1457	do anything special to have it called later.	1782	don't have to do anything special to have it called later.
1458		1783
1459	Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes	1784	Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes
1460	ready, it can be beneficial to call this function from loops which submit	1785	ready, it can be beneficial to call this function from loops which submit
1461	a lot of requests, to make sure the results get processed when they become	1786	a lot of requests, to make sure the results get processed when they become
1462	available and not just when the loop is finished and the event loop takes	1787	available and not just when the loop is finished and the event loop takes
…		…
1471	poll => 'r', async => 1,	1796	poll => 'r', async => 1,
1472	cb => \&IO::AIO::poll_cb);	1797	cb => \&IO::AIO::poll_cb);
1473		1798
1474	=item IO::AIO::poll_wait	1799	=item IO::AIO::poll_wait
1475		1800
1476	If there are any outstanding requests and none of them in the result	1801	Wait until either at least one request is in the result phase or no
1477	phase, wait till the result filehandle becomes ready for reading (simply	1802	requests are outstanding anymore.
1478	does a C<select> on the filehandle. This is useful if you want to	1803
1479	synchronously wait for some requests to finish).	1804	This is useful if you want to synchronously wait for some requests to
		1805	become ready, without actually handling them.
1480		1806
1481	See C<nreqs> for an example.	1807	See C<nreqs> for an example.
1482		1808
1483	=item IO::AIO::poll	1809	=item IO::AIO::poll
1484		1810
…		…
1605		1931
1606	This is a very bad function to use in interactive programs because it	1932	This is a very bad function to use in interactive programs because it
1607	blocks, and a bad way to reduce concurrency because it is inexact: Better	1933	blocks, and a bad way to reduce concurrency because it is inexact: Better
1608	use an C<aio_group> together with a feed callback.	1934	use an C<aio_group> together with a feed callback.
1609		1935
1610	It's main use is in scripts without an event loop - when you want to stat	1936	Its main use is in scripts without an event loop - when you want to stat
1611	a lot of files, you can write somehting like this:	1937	a lot of files, you can write somehting like this:
1612		1938
1613	IO::AIO::max_outstanding 32;	1939	IO::AIO::max_outstanding 32;
1614		1940
1615	for my $path (...) {	1941	for my $path (...) {
…		…
1655		1981
1656	=back	1982	=back
1657		1983
1658	=head3 MISCELLANEOUS FUNCTIONS	1984	=head3 MISCELLANEOUS FUNCTIONS
1659		1985
1660	IO::AIO implements some functions that might be useful, but are not	1986	IO::AIO implements some functions that are useful when you want to use
1661	asynchronous.	1987	some "Advanced I/O" function not available to in Perl, without going the
		1988	"Asynchronous I/O" route. Many of these have an asynchronous C<aio_*>
		1989	counterpart.
1662		1990
1663	=over 4	1991	=over 4
1664		1992
1665	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count	1993	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
1666		1994
…		…
1673		2001
1674	=item IO::AIO::fadvise $fh, $offset, $len, $advice	2002	=item IO::AIO::fadvise $fh, $offset, $len, $advice
1675		2003
1676	Simply calls the C<posix_fadvise> function (see its	2004	Simply calls the C<posix_fadvise> function (see its
1677	manpage for details). The following advice constants are	2005	manpage for details). The following advice constants are
1678	avaiable: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>,	2006	available: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>,
1679	C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>,	2007	C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>,
1680	C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>.	2008	C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>.
1681		2009
1682	On systems that do not implement C<posix_fadvise>, this function returns	2010	On systems that do not implement C<posix_fadvise>, this function returns
1683	ENOSYS, otherwise the return value of C<posix_fadvise>.	2011	ENOSYS, otherwise the return value of C<posix_fadvise>.
1684		2012
1685	=item IO::AIO::madvise $scalar, $offset, $len, $advice	2013	=item IO::AIO::madvise $scalar, $offset, $len, $advice
1686		2014
1687	Simply calls the C<posix_madvise> function (see its	2015	Simply calls the C<posix_madvise> function (see its
1688	manpage for details). The following advice constants are	2016	manpage for details). The following advice constants are
1689	avaiable: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,	2017	available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,
1690	C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>.	2018	C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>.
1691		2019
1692	On systems that do not implement C<posix_madvise>, this function returns	2020	On systems that do not implement C<posix_madvise>, this function returns
1693	ENOSYS, otherwise the return value of C<posix_madvise>.	2021	ENOSYS, otherwise the return value of C<posix_madvise>.
1694		2022
1695	=item IO::AIO::mprotect $scalar, $offset, $len, $protect	2023	=item IO::AIO::mprotect $scalar, $offset, $len, $protect
1696		2024
1697	Simply calls the C<mprotect> function on the preferably AIO::mmap'ed	2025	Simply calls the C<mprotect> function on the preferably AIO::mmap'ed
1698	$scalar (see its manpage for details). The following protect	2026	$scalar (see its manpage for details). The following protect
1699	constants are avaiable: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,	2027	constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,
1700	C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.	2028	C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.
1701		2029
1702	On systems that do not implement C<mprotect>, this function returns	2030	On systems that do not implement C<mprotect>, this function returns
1703	ENOSYS, otherwise the return value of C<mprotect>.	2031	ENOSYS, otherwise the return value of C<mprotect>.
1704		2032
1705	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]	2033	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]
1706		2034
1707	Memory-maps a file (or anonymous memory range) and attaches it to the	2035	Memory-maps a file (or anonymous memory range) and attaches it to the
1708	given C<$scalar>, which will act like a string scalar.	2036	given C<$scalar>, which will act like a string scalar. Returns true on
		2037	success, and false otherwise.
1709		2038
1710	The only operations allowed on the scalar are C<substr>/C<vec> that don't	2039	The only operations allowed on the scalar are C<substr>/C<vec> that don't
1711	change the string length, and most read-only operations such as copying it	2040	change the string length, and most read-only operations such as copying it
1712	or searching it with regexes and so on.	2041	or searching it with regexes and so on.
1713		2042
…		…
1766	Calls the C<munlockall> function.	2095	Calls the C<munlockall> function.
1767		2096
1768	On systems that do not implement C<munlockall>, this function returns	2097	On systems that do not implement C<munlockall>, this function returns
1769	ENOSYS, otherwise the return value of C<munlockall>.	2098	ENOSYS, otherwise the return value of C<munlockall>.
1770		2099
		2100	=item IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags
		2101
		2102	Calls the GNU/Linux C<splice(2)> syscall, if available. If C<$r_off> or
		2103	C<$w_off> are C<undef>, then C<NULL> is passed for these, otherwise they
		2104	should be the file offset.
		2105
		2106	C<$r_fh> and C<$w_fh> should not refer to the same file, as splice might
		2107	silently corrupt the data in this case.
		2108
		2109	The following symbol flag values are available: C<IO::AIO::SPLICE_F_MOVE>,
		2110	C<IO::AIO::SPLICE_F_NONBLOCK>, C<IO::AIO::SPLICE_F_MORE> and
		2111	C<IO::AIO::SPLICE_F_GIFT>.
		2112
		2113	See the C<splice(2)> manpage for details.
		2114
		2115	=item IO::AIO::tee $r_fh, $w_fh, $length, $flags
		2116
		2117	Calls the GNU/Linux C<tee(2)> syscall, see its manpage and the
		2118	description for C<IO::AIO::splice> above for details.
		2119
		2120	=item $actual_size = IO::AIO::pipesize $r_fh[, $new_size]
		2121
		2122	Attempts to query or change the pipe buffer size. Obviously works only
		2123	on pipes, and currently works only on GNU/Linux systems, and fails with
		2124	C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer
		2125	size on other systems, drop me a note.
		2126
1771	=back	2127	=back
1772		2128
1773	=cut	2129	=cut
1774		2130
1775	min_parallel 8;	2131	min_parallel 8;
…		…
1829		2185
1830	=over 4	2186	=over 4
1831		2187
1832	=item IO::AIO::reinit	2188	=item IO::AIO::reinit
1833		2189
1834	Abondons all current requests and I/O threads and simply reinitialises all	2190	Abandons all current requests and I/O threads and simply reinitialises all
1835	data structures. This is not an operation suppported by any standards, but	2191	data structures. This is not an operation supported by any standards, but
1836	happens to work on GNU/Linux and some newer BSD systems.	2192	happens to work on GNU/Linux and some newer BSD systems.
1837		2193
1838	The only reasonable use for this function is to call it after forking, if	2194	The only reasonable use for this function is to call it after forking, if
1839	C<IO::AIO> was used in the parent. Calling it while IO::AIO is active in	2195	C<IO::AIO> was used in the parent. Calling it while IO::AIO is active in
1840	the process will result in undefined behaviour. Calling it at any time	2196	the process will result in undefined behaviour. Calling it at any time

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Comparing IO-AIO/AIO.pm (file contents): Revision 1.206 by root, Sun Jul 24 03:32:51 2011 UTC vs. Revision 1.248 by root, Sun Jul 27 22:10:53 2014 UTC

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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.206 by root, Sun Jul 24 03:32:51 2011 UTC vs.
Revision 1.248 by root, Sun Jul 27 22:10:53 2014 UTC