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

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.203 by root, Thu Jul 7 22:36:18 2011 UTC vs.
Revision 1.242 by root, Sun Jan 6 11:48:13 2013 UTC

…		…
168	use common::sense;	168	use common::sense;
169		169
170	use base 'Exporter';	170	use base 'Exporter';
171		171
172	BEGIN {	172	BEGIN {
173	our $VERSION = '3.93';	173	our $VERSION = '4.19';
174		174
175	our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close	175	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	176	aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx
177	aio_scandir aio_symlink aio_readlink aio_realpath aio_sync aio_fsync	177	aio_scandir aio_symlink aio_readlink aio_realpath aio_sync
178	aio_fdatasync aio_sync_file_range aio_fallocate	178	aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range aio_allocate
179	aio_pathsync aio_readahead	179	aio_pathsync aio_readahead aio_fiemap
180	aio_rename aio_link aio_move aio_copy aio_group	180	aio_rename aio_link aio_move aio_copy aio_group
181	aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown	181	aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown
182	aio_chmod aio_utime aio_truncate	182	aio_chmod aio_utime aio_truncate
183	aio_msync aio_mtouch aio_mlock aio_mlockall	183	aio_msync aio_mtouch aio_mlock aio_mlockall
184	aio_statvfs);	184	aio_statvfs
		185	aio_wd);
185		186
186	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));	187	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));
187	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush	188	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush
188	min_parallel max_parallel max_idle idle_timeout	189	min_parallel max_parallel max_idle idle_timeout
189	nreqs nready npending nthreads	190	nreqs nready npending nthreads
…		…
201		202
202	=head1 FUNCTIONS	203	=head1 FUNCTIONS
203		204
204	=head2 QUICK OVERVIEW	205	=head2 QUICK OVERVIEW
205		206
206	This section simply lists the prototypes of the most important functions	207	This section simply lists the prototypes most of the functions for
207	for quick reference. See the following sections for function-by-function	208	quick reference. See the following sections for function-by-function
208	documentation.	209	documentation.
209		210
		211	aio_wd $pathname, $callback->($wd)
210	aio_open $pathname, $flags, $mode, $callback->($fh)	212	aio_open $pathname, $flags, $mode, $callback->($fh)
211	aio_close $fh, $callback->($status)	213	aio_close $fh, $callback->($status)
		214	aio_seek $fh,$offset,$whence, $callback->($offs)
212	aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	215	aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
213	aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	216	aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
214	aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)	217	aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
215	aio_readahead $fh,$offset,$length, $callback->($retval)	218	aio_readahead $fh,$offset,$length, $callback->($retval)
216	aio_stat $fh_or_path, $callback->($status)	219	aio_stat $fh_or_path, $callback->($status)
217	aio_lstat $fh, $callback->($status)	220	aio_lstat $fh, $callback->($status)
218	aio_statvfs $fh_or_path, $callback->($statvfs)	221	aio_statvfs $fh_or_path, $callback->($statvfs)
219	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	222	aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
220	aio_chown $fh_or_path, $uid, $gid, $callback->($status)	223	aio_chown $fh_or_path, $uid, $gid, $callback->($status)
		224	aio_chmod $fh_or_path, $mode, $callback->($status)
221	aio_truncate $fh_or_path, $offset, $callback->($status)	225	aio_truncate $fh_or_path, $offset, $callback->($status)
222	aio_chmod $fh_or_path, $mode, $callback->($status)	226	aio_allocate $fh, $mode, $offset, $len, $callback->($status)
		227	aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
223	aio_unlink $pathname, $callback->($status)	228	aio_unlink $pathname, $callback->($status)
224	aio_mknod $path, $mode, $dev, $callback->($status)	229	aio_mknod $pathname, $mode, $dev, $callback->($status)
225	aio_link $srcpath, $dstpath, $callback->($status)	230	aio_link $srcpath, $dstpath, $callback->($status)
226	aio_symlink $srcpath, $dstpath, $callback->($status)	231	aio_symlink $srcpath, $dstpath, $callback->($status)
227	aio_readlink $path, $callback->($link)	232	aio_readlink $pathname, $callback->($link)
228	aio_realpath $path, $callback->($link)	233	aio_realpath $pathname, $callback->($link)
229	aio_rename $srcpath, $dstpath, $callback->($status)	234	aio_rename $srcpath, $dstpath, $callback->($status)
230	aio_mkdir $pathname, $mode, $callback->($status)	235	aio_mkdir $pathname, $mode, $callback->($status)
231	aio_rmdir $pathname, $callback->($status)	236	aio_rmdir $pathname, $callback->($status)
232	aio_readdir $pathname, $callback->($entries)	237	aio_readdir $pathname, $callback->($entries)
233	aio_readdirx $pathname, $flags, $callback->($entries, $flags)	238	aio_readdirx $pathname, $flags, $callback->($entries, $flags)
234	IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST	239	IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST
235	IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN	240	IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN
		241	aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
236	aio_load $path, $data, $callback->($status)	242	aio_load $pathname, $data, $callback->($status)
237	aio_copy $srcpath, $dstpath, $callback->($status)	243	aio_copy $srcpath, $dstpath, $callback->($status)
238	aio_move $srcpath, $dstpath, $callback->($status)	244	aio_move $srcpath, $dstpath, $callback->($status)
239	aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
240	aio_rmtree $path, $callback->($status)	245	aio_rmtree $pathname, $callback->($status)
241	aio_sync $callback->($status)	246	aio_sync $callback->($status)
		247	aio_syncfs $fh, $callback->($status)
242	aio_fsync $fh, $callback->($status)	248	aio_fsync $fh, $callback->($status)
243	aio_fdatasync $fh, $callback->($status)	249	aio_fdatasync $fh, $callback->($status)
244	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)	250	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
245	aio_pathsync $path, $callback->($status)	251	aio_pathsync $pathname, $callback->($status)
246	aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	252	aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
247	aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)	253	aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
248	aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)	254	aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
249	aio_mlockall $flags, $callback->($status)	255	aio_mlockall $flags, $callback->($status)
250	aio_group $callback->(...)	256	aio_group $callback->(...)
…		…
268	IO::AIO::nready	274	IO::AIO::nready
269	IO::AIO::npending	275	IO::AIO::npending
270		276
271	IO::AIO::sendfile $ofh, $ifh, $offset, $count	277	IO::AIO::sendfile $ofh, $ifh, $offset, $count
272	IO::AIO::fadvise $fh, $offset, $len, $advice	278	IO::AIO::fadvise $fh, $offset, $len, $advice
		279	IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]]
		280	IO::AIO::munmap $scalar
273	IO::AIO::madvise $scalar, $offset, $length, $advice	281	IO::AIO::madvise $scalar, $offset, $length, $advice
274	IO::AIO::mprotect $scalar, $offset, $length, $protect	282	IO::AIO::mprotect $scalar, $offset, $length, $protect
275	IO::AIO::munlock $scalar, $offset = 0, $length = undef	283	IO::AIO::munlock $scalar, $offset = 0, $length = undef
276	IO::AIO::munlockall	284	IO::AIO::munlockall
277		285
278	=head2 AIO REQUEST FUNCTIONS	286	=head2 API NOTES
279		287
280	All the C<aio_*> calls are more or less thin wrappers around the syscall	288	All the C<aio_*> calls are more or less thin wrappers around the syscall
281	with the same name (sans C<aio_>). The arguments are similar or identical,	289	with the same name (sans C<aio_>). The arguments are similar or identical,
282	and they all accept an additional (and optional) C<$callback> argument	290	and they all accept an additional (and optional) C<$callback> argument
283	which must be a code reference. This code reference will get called with	291	which must be a code reference. This code reference will be called after
284	the syscall return code (e.g. most syscalls return C<-1> on error, unlike	292	the syscall has been executed in an asynchronous fashion. The results
285	perl, which usually delivers "false") as its sole argument after the given	293	of the request will be passed as arguments to the callback (and, if an
286	syscall has been executed asynchronously.	294	error occured, in C<$!>) - for most requests the syscall return code (e.g.
		295	most syscalls return C<-1> on error, unlike perl, which usually delivers
		296	"false").
		297
		298	Some requests (such as C<aio_readdir>) pass the actual results and
		299	communicate failures by passing C<undef>.
287		300
288	All functions expecting a filehandle keep a copy of the filehandle	301	All functions expecting a filehandle keep a copy of the filehandle
289	internally until the request has finished.	302	internally until the request has finished.
290		303
291	All functions return request objects of type L<IO::AIO::REQ> that allow	304	All functions return request objects of type L<IO::AIO::REQ> that allow
292	further manipulation of those requests while they are in-flight.	305	further manipulation of those requests while they are in-flight.
293		306
294	The pathnames you pass to these routines I<must> be absolute and	307	The pathnames you pass to these routines I<should> be absolute. The
295	encoded as octets. The reason for the former is that at the time the	308	reason for this is that at the time the request is being executed, the
296	request is being executed, the current working directory could have	309	current working directory could have changed. Alternatively, you can
297	changed. Alternatively, you can make sure that you never change the	310	make sure that you never change the current working directory anywhere
298	current working directory anywhere in the program and then use relative	311	in the program and then use relative paths. You can also take advantage
299	paths.	312	of IO::AIOs working directory abstraction, that lets you specify paths
		313	relative to some previously-opened "working directory object" - see the
		314	description of the C<IO::AIO::WD> class later in this document.
300		315
301	To encode pathnames as octets, either make sure you either: a) always pass	316	To encode pathnames as octets, either make sure you either: a) always pass
302	in filenames you got from outside (command line, readdir etc.) without	317	in filenames you got from outside (command line, readdir etc.) without
303	tinkering, b) are ASCII or ISO 8859-1, c) use the Encode module and encode	318	tinkering, b) are in your native filesystem encoding, c) use the Encode
304	your pathnames to the locale (or other) encoding in effect in the user	319	module and encode your pathnames to the locale (or other) encoding in
305	environment, d) use Glib::filename_from_unicode on unicode filenames or e)	320	effect in the user environment, d) use Glib::filename_from_unicode on
306	use something else to ensure your scalar has the correct contents.	321	unicode filenames or e) use something else to ensure your scalar has the
		322	correct contents.
307		323
308	This works, btw. independent of the internal UTF-8 bit, which IO::AIO	324	This works, btw. independent of the internal UTF-8 bit, which IO::AIO
309	handles correctly whether it is set or not.	325	handles correctly whether it is set or not.
		326
		327	=head2 AIO REQUEST FUNCTIONS
310		328
311	=over 4	329	=over 4
312		330
313	=item $prev_pri = aioreq_pri [$pri]	331	=item $prev_pri = aioreq_pri [$pri]
314		332
…		…
344		362
345		363
346	=item aio_open $pathname, $flags, $mode, $callback->($fh)	364	=item aio_open $pathname, $flags, $mode, $callback->($fh)
347		365
348	Asynchronously open or create a file and call the callback with a newly	366	Asynchronously open or create a file and call the callback with a newly
349	created filehandle for the file.	367	created filehandle for the file (or C<undef> in case of an error).
350		368
351	The pathname passed to C<aio_open> must be absolute. See API NOTES, above,	369	The pathname passed to C<aio_open> must be absolute. See API NOTES, above,
352	for an explanation.	370	for an explanation.
353		371
354	The C<$flags> argument is a bitmask. See the C<Fcntl> module for a	372	The C<$flags> argument is a bitmask. See the C<Fcntl> module for a
…		…
396		414
397	Or in other words: the file descriptor will be closed, but it will not be	415	Or in other words: the file descriptor will be closed, but it will not be
398	free for reuse until the perl filehandle is closed.	416	free for reuse until the perl filehandle is closed.
399		417
400	=cut	418	=cut
		419
		420	=item aio_seek $fh, $offset, $whence, $callback->($offs)
		421
		422	Seeks the filehandle to the new C<$offset>, similarly to perl's
		423	C<sysseek>. The C<$whence> can use the traditional values (C<0> for
		424	C<IO::AIO::SEEK_SET>, C<1> for C<IO::AIO::SEEK_CUR> or C<2> for
		425	C<IO::AIO::SEEK_END>).
		426
		427	The resulting absolute offset will be passed to the callback, or C<-1> in
		428	case of an error.
		429
		430	In theory, the C<$whence> constants could be different than the
		431	corresponding values from L<Fcntl>, but perl guarantees they are the same,
		432	so don't panic.
		433
		434	As a GNU/Linux (and maybe Solaris) extension, also the constants
		435	C<IO::AIO::SEEK_DATA> and C<IO::AIO::SEEK_HOLE> are available, if they
		436	could be found. No guarantees about suitability for use in C<aio_seek> or
		437	Perl's C<sysseek> can be made though, although I would naively assume they
		438	"just work".
401		439
402	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	440	=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
403		441
404	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)	442	=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
405		443
…		…
565	namemax => 255,	603	namemax => 255,
566	frsize => 1024,	604	frsize => 1024,
567	fsid => 1810	605	fsid => 1810
568	}	606	}
569		607
		608	Here is a (likely partial) list of fsid values used by Linux - it is safe
		609	to hardcode these when the $^O is C<linux>:
		610
		611	0x0000adf5 adfs
		612	0x0000adff affs
		613	0x5346414f afs
		614	0x09041934 anon-inode filesystem
		615	0x00000187 autofs
		616	0x42465331 befs
		617	0x1badface bfs
		618	0x42494e4d binfmt_misc
		619	0x9123683e btrfs
		620	0x0027e0eb cgroupfs
		621	0xff534d42 cifs
		622	0x73757245 coda
		623	0x012ff7b7 coh
		624	0x28cd3d45 cramfs
		625	0x453dcd28 cramfs-wend (wrong endianness)
		626	0x64626720 debugfs
		627	0x00001373 devfs
		628	0x00001cd1 devpts
		629	0x0000f15f ecryptfs
		630	0x00414a53 efs
		631	0x0000137d ext
		632	0x0000ef53 ext2/ext3
		633	0x0000ef51 ext2
		634	0x00004006 fat
		635	0x65735546 fuseblk
		636	0x65735543 fusectl
		637	0x0bad1dea futexfs
		638	0x01161970 gfs2
		639	0x47504653 gpfs
		640	0x00004244 hfs
		641	0xf995e849 hpfs
		642	0x958458f6 hugetlbfs
		643	0x2bad1dea inotifyfs
		644	0x00009660 isofs
		645	0x000072b6 jffs2
		646	0x3153464a jfs
		647	0x6b414653 k-afs
		648	0x0bd00bd0 lustre
		649	0x0000137f minix
		650	0x0000138f minix 30 char names
		651	0x00002468 minix v2
		652	0x00002478 minix v2 30 char names
		653	0x00004d5a minix v3
		654	0x19800202 mqueue
		655	0x00004d44 msdos
		656	0x0000564c novell
		657	0x00006969 nfs
		658	0x6e667364 nfsd
		659	0x00003434 nilfs
		660	0x5346544e ntfs
		661	0x00009fa1 openprom
		662	0x7461636F ocfs2
		663	0x00009fa0 proc
		664	0x6165676c pstorefs
		665	0x0000002f qnx4
		666	0x858458f6 ramfs
		667	0x52654973 reiserfs
		668	0x00007275 romfs
		669	0x67596969 rpc_pipefs
		670	0x73636673 securityfs
		671	0xf97cff8c selinux
		672	0x0000517b smb
		673	0x534f434b sockfs
		674	0x73717368 squashfs
		675	0x62656572 sysfs
		676	0x012ff7b6 sysv2
		677	0x012ff7b5 sysv4
		678	0x01021994 tmpfs
		679	0x15013346 udf
		680	0x00011954 ufs
		681	0x54190100 ufs byteswapped
		682	0x00009fa2 usbdevfs
		683	0x01021997 v9fs
		684	0xa501fcf5 vxfs
		685	0xabba1974 xenfs
		686	0x012ff7b4 xenix
		687	0x58465342 xfs
		688	0x012fd16d xia
570		689
571	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	690	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
572		691
573	Works like perl's C<utime> function (including the special case of $atime	692	Works like perl's C<utime> function (including the special case of $atime
574	and $mtime being undef). Fractional times are supported if the underlying	693	and $mtime being undef). Fractional times are supported if the underlying
…		…
602	=item aio_truncate $fh_or_path, $offset, $callback->($status)	721	=item aio_truncate $fh_or_path, $offset, $callback->($status)
603		722
604	Works like truncate(2) or ftruncate(2).	723	Works like truncate(2) or ftruncate(2).
605		724
606		725
		726	=item aio_allocate $fh, $mode, $offset, $len, $callback->($status)
		727
		728	Allocates or freed disk space according to the C<$mode> argument. See the
		729	linux C<fallocate> docuemntation for details.
		730
		731	C<$mode> can currently be C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE>
		732	to allocate space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE \|
		733	IO::AIO::FALLOC_FL_KEEP_SIZE>, to deallocate a file range.
		734
		735	The file system block size used by C<fallocate> is presumably the
		736	C<f_bsize> returned by C<statvfs>.
		737
		738	If C<fallocate> isn't available or cannot be emulated (currently no
		739	emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>.
		740
		741
607	=item aio_chmod $fh_or_path, $mode, $callback->($status)	742	=item aio_chmod $fh_or_path, $mode, $callback->($status)
608		743
609	Works like perl's C<chmod> function.	744	Works like perl's C<chmod> function.
610		745
611		746
…		…
613		748
614	Asynchronously unlink (delete) a file and call the callback with the	749	Asynchronously unlink (delete) a file and call the callback with the
615	result code.	750	result code.
616		751
617		752
618	=item aio_mknod $path, $mode, $dev, $callback->($status)	753	=item aio_mknod $pathname, $mode, $dev, $callback->($status)
619		754
620	[EXPERIMENTAL]	755	[EXPERIMENTAL]
621		756
622	Asynchronously create a device node (or fifo). See mknod(2).	757	Asynchronously create a device node (or fifo). See mknod(2).
623		758
624	The only (POSIX-) portable way of calling this function is:	759	The only (POSIX-) portable way of calling this function is:
625		760
626	aio_mknod $path, IO::AIO::S_IFIFO \| $mode, 0, sub { ...	761	aio_mknod $pathname, IO::AIO::S_IFIFO \| $mode, 0, sub { ...
627		762
628	See C<aio_stat> for info about some potentially helpful extra constants	763	See C<aio_stat> for info about some potentially helpful extra constants
629	and functions.	764	and functions.
630		765
631	=item aio_link $srcpath, $dstpath, $callback->($status)	766	=item aio_link $srcpath, $dstpath, $callback->($status)
…		…
638		773
639	Asynchronously create a new symbolic link to the existing object at C<$srcpath> at	774	Asynchronously create a new symbolic link to the existing object at C<$srcpath> at
640	the path C<$dstpath> and call the callback with the result code.	775	the path C<$dstpath> and call the callback with the result code.
641		776
642		777
643	=item aio_readlink $path, $callback->($link)	778	=item aio_readlink $pathname, $callback->($link)
644		779
645	Asynchronously read the symlink specified by C<$path> and pass it to	780	Asynchronously read the symlink specified by C<$path> and pass it to
646	the callback. If an error occurs, nothing or undef gets passed to the	781	the callback. If an error occurs, nothing or undef gets passed to the
647	callback.	782	callback.
648		783
649		784
650	=item aio_realpath $path, $callback->($path)	785	=item aio_realpath $pathname, $callback->($path)
651		786
652	Asynchronously make the path absolute and resolve any symlinks in	787	Asynchronously make the path absolute and resolve any symlinks in
653	C<$path>. The resulting path only consists of directories (Same as	788	C<$path>. The resulting path only consists of directories (same as
654	L<Cwd::realpath>).	789	L<Cwd::realpath>).
655		790
656	This request can be used to get the absolute path of the current working	791	This request can be used to get the absolute path of the current working
657	directory by passing it a path of F<.> (a single dot).	792	directory by passing it a path of F<.> (a single dot).
658		793
659		794
660	=item aio_rename $srcpath, $dstpath, $callback->($status)	795	=item aio_rename $srcpath, $dstpath, $callback->($status)
661		796
662	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as	797	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as
663	rename(2) and call the callback with the result code.	798	rename(2) and call the callback with the result code.
		799
		800	On systems that support the AIO::WD working directory abstraction
		801	natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead
		802	of failing, C<rename> is called on the absolute path of C<$wd>.
664		803
665		804
666	=item aio_mkdir $pathname, $mode, $callback->($status)	805	=item aio_mkdir $pathname, $mode, $callback->($status)
667		806
668	Asynchronously mkdir (create) a directory and call the callback with	807	Asynchronously mkdir (create) a directory and call the callback with
…		…
673	=item aio_rmdir $pathname, $callback->($status)	812	=item aio_rmdir $pathname, $callback->($status)
674		813
675	Asynchronously rmdir (delete) a directory and call the callback with the	814	Asynchronously rmdir (delete) a directory and call the callback with the
676	result code.	815	result code.
677		816
		817	On systems that support the AIO::WD working directory abstraction
		818	natively, the case C<[$wd, "."]> is specialcased - instead of failing,
		819	C<rmdir> is called on the absolute path of C<$wd>.
		820
678		821
679	=item aio_readdir $pathname, $callback->($entries)	822	=item aio_readdir $pathname, $callback->($entries)
680		823
681	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire	824	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire
682	directory (i.e. opendir + readdir + closedir). The entries will not be	825	directory (i.e. opendir + readdir + closedir). The entries will not be
…		…
686	array-ref with the filenames.	829	array-ref with the filenames.
687		830
688		831
689	=item aio_readdirx $pathname, $flags, $callback->($entries, $flags)	832	=item aio_readdirx $pathname, $flags, $callback->($entries, $flags)
690		833
691	Quite similar to C<aio_readdir>, but the C<$flags> argument allows to tune	834	Quite similar to C<aio_readdir>, but the C<$flags> argument allows one to
692	behaviour and output format. In case of an error, C<$entries> will be	835	tune behaviour and output format. In case of an error, C<$entries> will be
693	C<undef>.	836	C<undef>.
694		837
695	The flags are a combination of the following constants, ORed together (the	838	The flags are a combination of the following constants, ORed together (the
696	flags will also be passed to the callback, possibly modified):	839	flags will also be passed to the callback, possibly modified):
697		840
…		…
744		887
745	=item IO::AIO::READDIR_FOUND_UNKNOWN	888	=item IO::AIO::READDIR_FOUND_UNKNOWN
746		889
747	This flag should not be set when calling C<aio_readdirx>. Instead, it	890	This flag should not be set when calling C<aio_readdirx>. Instead, it
748	is being set by C<aio_readdirx>, when any of the C<$type>'s found were	891	is being set by C<aio_readdirx>, when any of the C<$type>'s found were
749	C<IO::AIO::DT_UNKNOWN>. The absense of this flag therefore indicates that all	892	C<IO::AIO::DT_UNKNOWN>. The absence of this flag therefore indicates that all
750	C<$type>'s are known, which can be used to speed up some algorithms.	893	C<$type>'s are known, which can be used to speed up some algorithms.
751		894
752	=back	895	=back
753		896
754		897
755	=item aio_load $path, $data, $callback->($status)	898	=item aio_load $pathname, $data, $callback->($status)
756		899
757	This is a composite request that tries to fully load the given file into	900	This is a composite request that tries to fully load the given file into
758	memory. Status is the same as with aio_read.	901	memory. Status is the same as with aio_read.
759		902
760	=cut	903	=cut
…		…
895	};	1038	};
896		1039
897	$grp	1040	$grp
898	}	1041	}
899		1042
900	=item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)	1043	=item aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
901		1044
902	Scans a directory (similar to C<aio_readdir>) but additionally tries to	1045	Scans a directory (similar to C<aio_readdir>) but additionally tries to
903	efficiently separate the entries of directory C<$path> into two sets of	1046	efficiently separate the entries of directory C<$path> into two sets of
904	names, directories you can recurse into (directories), and ones you cannot	1047	names, directories you can recurse into (directories), and ones you cannot
905	recurse into (everything else, including symlinks to directories).	1048	recurse into (everything else, including symlinks to directories).
…		…
936	Then entries will be sorted into likely directories a non-initial dot	1079	Then entries will be sorted into likely directories a non-initial dot
937	currently) and likely non-directories (see C<aio_readdirx>). Then every	1080	currently) and likely non-directories (see C<aio_readdirx>). Then every
938	entry plus an appended C</.> will be C<stat>'ed, likely directories first,	1081	entry plus an appended C</.> will be C<stat>'ed, likely directories first,
939	in order of their inode numbers. If that succeeds, it assumes that the	1082	in order of their inode numbers. If that succeeds, it assumes that the
940	entry is a directory or a symlink to directory (which will be checked	1083	entry is a directory or a symlink to directory (which will be checked
941	seperately). This is often faster than stat'ing the entry itself because	1084	separately). This is often faster than stat'ing the entry itself because
942	filesystems might detect the type of the entry without reading the inode	1085	filesystems might detect the type of the entry without reading the inode
943	data (e.g. ext2fs filetype feature), even on systems that cannot return	1086	data (e.g. ext2fs filetype feature), even on systems that cannot return
944	the filetype information on readdir.	1087	the filetype information on readdir.
945		1088
946	If the known number of directories (link count - 2) has been reached, the	1089	If the known number of directories (link count - 2) has been reached, the
…		…
962		1105
963	my $grp = aio_group $cb;	1106	my $grp = aio_group $cb;
964		1107
965	$maxreq = 4 if $maxreq <= 0;	1108	$maxreq = 4 if $maxreq <= 0;
966		1109
967	# stat once	1110	# get a wd object
968	aioreq_pri $pri;	1111	aioreq_pri $pri;
969	add $grp aio_stat $path, sub {	1112	add $grp aio_wd $path, sub {
		1113	$_[0]
970	return $grp->result () if $_[0];	1114	or return $grp->result ();
971	my $now = time;
972	my $hash1 = join ":", (stat _)[0,1,3,7,9];
973		1115
974	# read the directory entries	1116	my $wd = [shift, "."];
		1117
		1118	# stat once
975	aioreq_pri $pri;	1119	aioreq_pri $pri;
976	add $grp aio_readdirx $path, READDIR_DIRS_FIRST, sub {	1120	add $grp aio_stat $wd, sub {
977	my $entries = shift
978	or return $grp->result ();	1121	return $grp->result () if $_[0];
		1122	my $now = time;
		1123	my $hash1 = join ":", (stat _)[0,1,3,7,9];
979		1124
980	# stat the dir another time	1125	# read the directory entries
981	aioreq_pri $pri;	1126	aioreq_pri $pri;
		1127	add $grp aio_readdirx $wd, READDIR_DIRS_FIRST, sub {
		1128	my $entries = shift
		1129	or return $grp->result ();
		1130
		1131	# stat the dir another time
		1132	aioreq_pri $pri;
982	add $grp aio_stat $path, sub {	1133	add $grp aio_stat $wd, sub {
983	my $hash2 = join ":", (stat _)[0,1,3,7,9];	1134	my $hash2 = join ":", (stat _)[0,1,3,7,9];
984		1135
985	my $ndirs;	1136	my $ndirs;
986		1137
987	# take the slow route if anything looks fishy	1138	# take the slow route if anything looks fishy
988	if ($hash1 ne $hash2 or (stat _)[9] == $now) {	1139	if ($hash1 ne $hash2 or (stat _)[9] == $now) {
989	$ndirs = -1;	1140	$ndirs = -1;
990	} else {	1141	} else {
991	# if nlink == 2, we are finished	1142	# if nlink == 2, we are finished
992	# for non-posix-fs's, we rely on nlink < 2	1143	# for non-posix-fs's, we rely on nlink < 2
993	$ndirs = (stat _)[3] - 2	1144	$ndirs = (stat _)[3] - 2
994	or return $grp->result ([], $entries);	1145	or return $grp->result ([], $entries);
995	}	1146	}
996		1147
997	my (@dirs, @nondirs);	1148	my (@dirs, @nondirs);
998		1149
999	my $statgrp = add $grp aio_group sub {	1150	my $statgrp = add $grp aio_group sub {
1000	$grp->result (\@dirs, \@nondirs);	1151	$grp->result (\@dirs, \@nondirs);
1001	};	1152	};
1002		1153
1003	limit $statgrp $maxreq;	1154	limit $statgrp $maxreq;
1004	feed $statgrp sub {	1155	feed $statgrp sub {
1005	return unless @$entries;	1156	return unless @$entries;
1006	my $entry = shift @$entries;	1157	my $entry = shift @$entries;
1007		1158
1008	aioreq_pri $pri;	1159	aioreq_pri $pri;
		1160	$wd->[1] = "$entry/.";
1009	add $statgrp aio_stat "$path/$entry/.", sub {	1161	add $statgrp aio_stat $wd, sub {
1010	if ($_[0] < 0) {	1162	if ($_[0] < 0) {
1011	push @nondirs, $entry;	1163	push @nondirs, $entry;
1012	} else {	1164	} else {
1013	# need to check for real directory	1165	# need to check for real directory
1014	aioreq_pri $pri;	1166	aioreq_pri $pri;
		1167	$wd->[1] = $entry;
1015	add $statgrp aio_lstat "$path/$entry", sub {	1168	add $statgrp aio_lstat $wd, sub {
1016	if (-d _) {	1169	if (-d _) {
1017	push @dirs, $entry;	1170	push @dirs, $entry;
1018		1171
1019	unless (--$ndirs) {	1172	unless (--$ndirs) {
1020	push @nondirs, @$entries;	1173	push @nondirs, @$entries;
1021	feed $statgrp;	1174	feed $statgrp;
		1175	}
		1176	} else {
		1177	push @nondirs, $entry;
1022	}	1178	}
1023	} else {
1024	push @nondirs, $entry;
1025	}	1179	}
1026	}	1180	}
1027	}	1181	};
1028	};	1182	};
1029	};	1183	};
1030	};	1184	};
1031	};	1185	};
1032	};	1186	};
1033		1187
1034	$grp	1188	$grp
1035	}	1189	}
1036		1190
1037	=item aio_rmtree $path, $callback->($status)	1191	=item aio_rmtree $pathname, $callback->($status)
1038		1192
1039	Delete a directory tree starting (and including) C<$path>, return the	1193	Delete a directory tree starting (and including) C<$path>, return the
1040	status of the final C<rmdir> only. This is a composite request that	1194	status of the final C<rmdir> only. This is a composite request that
1041	uses C<aio_scandir> to recurse into and rmdir directories, and unlink	1195	uses C<aio_scandir> to recurse into and rmdir directories, and unlink
1042	everything else.	1196	everything else.
1043		1197
1044	=cut	1198	=cut
1045		1199
…		…
1084	callback with the fdatasync result code.	1238	callback with the fdatasync result code.
1085		1239
1086	If this call isn't available because your OS lacks it or it couldn't be	1240	If this call isn't available because your OS lacks it or it couldn't be
1087	detected, it will be emulated by calling C<fsync> instead.	1241	detected, it will be emulated by calling C<fsync> instead.
1088		1242
		1243	=item aio_syncfs $fh, $callback->($status)
		1244
		1245	Asynchronously call the syncfs syscall to sync the filesystem associated
		1246	to the given filehandle and call the callback with the syncfs result
		1247	code. If syncfs is not available, calls sync(), but returns C<-1> and sets
		1248	errno to C<ENOSYS> nevertheless.
		1249
1089	=item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)	1250	=item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
1090		1251
1091	Sync the data portion of the file specified by C<$offset> and C<$length>	1252	Sync the data portion of the file specified by C<$offset> and C<$length>
1092	to disk (but NOT the metadata), by calling the Linux-specific	1253	to disk (but NOT the metadata), by calling the Linux-specific
1093	sync_file_range call. If sync_file_range is not available or it returns	1254	sync_file_range call. If sync_file_range is not available or it returns
…		…
1096	C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>,	1257	C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>,
1097	C<IO::AIO::SYNC_FILE_RANGE_WRITE> and	1258	C<IO::AIO::SYNC_FILE_RANGE_WRITE> and
1098	C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range	1259	C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range
1099	manpage for details.	1260	manpage for details.
1100		1261
1101	=item aio_pathsync $path, $callback->($status)	1262	=item aio_pathsync $pathname, $callback->($status)
1102		1263
1103	This request tries to open, fsync and close the given path. This is a	1264	This request tries to open, fsync and close the given path. This is a
1104	composite request intended to sync directories after directory operations	1265	composite request intended to sync directories after directory operations
1105	(E.g. rename). This might not work on all operating systems or have any	1266	(E.g. rename). This might not work on all operating systems or have any
1106	specific effect, but usually it makes sure that directory changes get	1267	specific effect, but usually it makes sure that directory changes get
…		…
1158		1319
1159	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1320	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
1160	scalars.	1321	scalars.
1161		1322
1162	It touches (reads or writes) all memory pages in the specified	1323	It touches (reads or writes) all memory pages in the specified
1163	range inside the scalar. All caveats and parameters are the same	1324	range inside the scalar. All caveats and parameters are the same
1164	as for C<aio_msync>, above, except for flags, which must be either	1325	as for C<aio_msync>, above, except for flags, which must be either
1165	C<0> (which reads all pages and ensures they are instantiated) or	1326	C<0> (which reads all pages and ensures they are instantiated) or
1166	C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and	1327	C<IO::AIO::MT_MODIFY>, which modifies the memory pages (by reading and
1167	writing an octet from it, which dirties the page).	1328	writing an octet from it, which dirties the page).
1168		1329
1169	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)	1330	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
1170		1331
1171	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1332	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
…		…
1202	documented under L<MISCELLANEOUS FUNCTIONS>.	1363	documented under L<MISCELLANEOUS FUNCTIONS>.
1203		1364
1204	Example: asynchronously lock all current and future pages into memory.	1365	Example: asynchronously lock all current and future pages into memory.
1205		1366
1206	aio_mlockall IO::AIO::MCL_FUTURE;	1367	aio_mlockall IO::AIO::MCL_FUTURE;
		1368
		1369	=item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents)
		1370
		1371	Queries the extents of the given file (by calling the Linux C<FIEMAP>
		1372	ioctl, see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If
		1373	the ioctl is not available on your OS, then this request will fail with
		1374	C<ENOSYS>.
		1375
		1376	C<$start> is the starting offset to query extents for, C<$length> is the
		1377	size of the range to query - if it is C<undef>, then the whole file will
		1378	be queried.
		1379
		1380	C<$flags> is a combination of flags (C<IO::AIO::FIEMAP_FLAG_SYNC> or
		1381	C<IO::AIO::FIEMAP_FLAG_XATTR> - C<IO::AIO::FIEMAP_FLAGS_COMPAT> is also
		1382	exported), and is normally C<0> or C<IO::AIO::FIEMAP_FLAG_SYNC> to query
		1383	the data portion.
		1384
		1385	C<$count> is the maximum number of extent records to return. If it is
		1386	C<undef>, then IO::AIO queries all extents of the range. As a very special
		1387	case, if it is C<0>, then the callback receives the number of extents
		1388	instead of the extents themselves (which is unreliable, see below).
		1389
		1390	If an error occurs, the callback receives no arguments. The special
		1391	C<errno> value C<IO::AIO::EBADR> is available to test for flag errors.
		1392
		1393	Otherwise, the callback receives an array reference with extent
		1394	structures. Each extent structure is an array reference itself, with the
		1395	following members:
		1396
		1397	[$logical, $physical, $length, $flags]
		1398
		1399	Flags is any combination of the following flag values (typically either C<0>
		1400	or C<IO::AIO::FIEMAP_EXTENT_LAST> (1)):
		1401
		1402	C<IO::AIO::FIEMAP_EXTENT_LAST>, C<IO::AIO::FIEMAP_EXTENT_UNKNOWN>,
		1403	C<IO::AIO::FIEMAP_EXTENT_DELALLOC>, C<IO::AIO::FIEMAP_EXTENT_ENCODED>,
		1404	C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>,
		1405	C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>,
		1406	C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or
		1407	C<IO::AIO::FIEMAP_EXTENT_SHARED>.
		1408
		1409	At the time of this writing (Linux 3.2), this requets is unreliable unless
		1410	C<$count> is C<undef>, as the kernel has all sorts of bugs preventing
		1411	it to return all extents of a range for files with large number of
		1412	extents. The code works around all these issues if C<$count> is undef.
1207		1413
1208	=item aio_group $callback->(...)	1414	=item aio_group $callback->(...)
1209		1415
1210	This is a very special aio request: Instead of doing something, it is a	1416	This is a very special aio request: Instead of doing something, it is a
1211	container for other aio requests, which is useful if you want to bundle	1417	container for other aio requests, which is useful if you want to bundle
…		…
1248	like sleep and file handle readable/writable, the overhead this creates is	1454	like sleep and file handle readable/writable, the overhead this creates is
1249	immense (it blocks a thread for a long time) so do not use this function	1455	immense (it blocks a thread for a long time) so do not use this function
1250	except to put your application under artificial I/O pressure.	1456	except to put your application under artificial I/O pressure.
1251		1457
1252	=back	1458	=back
		1459
		1460
		1461	=head2 IO::AIO::WD - multiple working directories
		1462
		1463	Your process only has one current working directory, which is used by all
		1464	threads. This makes it hard to use relative paths (some other component
		1465	could call C<chdir> at any time, and it is hard to control when the path
		1466	will be used by IO::AIO).
		1467
		1468	One solution for this is to always use absolute paths. This usually works,
		1469	but can be quite slow (the kernel has to walk the whole path on every
		1470	access), and can also be a hassle to implement.
		1471
		1472	Newer POSIX systems have a number of functions (openat, fdopendir,
		1473	futimensat and so on) that make it possible to specify working directories
		1474	per operation.
		1475
		1476	For portability, and because the clowns who "designed", or shall I write,
		1477	perpetrated this new interface were obviously half-drunk, this abstraction
		1478	cannot be perfect, though.
		1479
		1480	IO::AIO allows you to convert directory paths into a so-called IO::AIO::WD
		1481	object. This object stores the canonicalised, absolute version of the
		1482	path, and on systems that allow it, also a directory file descriptor.
		1483
		1484	Everywhere where a pathname is accepted by IO::AIO (e.g. in C<aio_stat>
		1485	or C<aio_unlink>), one can specify an array reference with an IO::AIO::WD
		1486	object and a pathname instead (or the IO::AIO::WD object alone, which
		1487	gets interpreted as C<[$wd, "."]>). If the pathname is absolute, the
		1488	IO::AIO::WD object is ignored, otherwise the pathname is resolved relative
		1489	to that IO::AIO::WD object.
		1490
		1491	For example, to get a wd object for F</etc> and then stat F<passwd>
		1492	inside, you would write:
		1493
		1494	aio_wd "/etc", sub {
		1495	my $etcdir = shift;
		1496
		1497	# although $etcdir can be undef on error, there is generally no reason
		1498	# to check for errors here, as aio_stat will fail with ENOENT
		1499	# when $etcdir is undef.
		1500
		1501	aio_stat [$etcdir, "passwd"], sub {
		1502	# yay
		1503	};
		1504	};
		1505
		1506	That C<aio_wd> is a request and not a normal function shows that creating
		1507	an IO::AIO::WD object is itself a potentially blocking operation, which is
		1508	why it is done asynchronously.
		1509
		1510	To stat the directory obtained with C<aio_wd> above, one could write
		1511	either of the following three request calls:
		1512
		1513	aio_lstat "/etc" , sub { ... # pathname as normal string
		1514	aio_lstat [$wd, "."], sub { ... # "." relative to $wd (i.e. $wd itself)
		1515	aio_lstat $wd , sub { ... # shorthand for the previous
		1516
		1517	As with normal pathnames, IO::AIO keeps a copy of the working directory
		1518	object and the pathname string, so you could write the following without
		1519	causing any issues due to C<$path> getting reused:
		1520
		1521	my $path = [$wd, undef];
		1522
		1523	for my $name (qw(abc def ghi)) {
		1524	$path->[1] = $name;
		1525	aio_stat $path, sub {
		1526	# ...
		1527	};
		1528	}
		1529
		1530	There are some caveats: when directories get renamed (or deleted), the
		1531	pathname string doesn't change, so will point to the new directory (or
		1532	nowhere at all), while the directory fd, if available on the system,
		1533	will still point to the original directory. Most functions accepting a
		1534	pathname will use the directory fd on newer systems, and the string on
		1535	older systems. Some functions (such as realpath) will always rely on the
		1536	string form of the pathname.
		1537
		1538	So this functionality is mainly useful to get some protection against
		1539	C<chdir>, to easily get an absolute path out of a relative path for future
		1540	reference, and to speed up doing many operations in the same directory
		1541	(e.g. when stat'ing all files in a directory).
		1542
		1543	The following functions implement this working directory abstraction:
		1544
		1545	=over 4
		1546
		1547	=item aio_wd $pathname, $callback->($wd)
		1548
		1549	Asynchonously canonicalise the given pathname and convert it to an
		1550	IO::AIO::WD object representing it. If possible and supported on the
		1551	system, also open a directory fd to speed up pathname resolution relative
		1552	to this working directory.
		1553
		1554	If something goes wrong, then C<undef> is passwd to the callback instead
		1555	of a working directory object and C<$!> is set appropriately. Since
		1556	passing C<undef> as working directory component of a pathname fails the
		1557	request with C<ENOENT>, there is often no need for error checking in the
		1558	C<aio_wd> callback, as future requests using the value will fail in the
		1559	expected way.
		1560
		1561	If this call isn't available because your OS lacks it or it couldn't be
		1562	detected, it will be emulated by calling C<fsync> instead.
		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.
1253		1587
1254	=head2 IO::AIO::REQ CLASS	1588	=head2 IO::AIO::REQ CLASS
1255		1589
1256	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
1257	called in non-void context.	1591	called in non-void context.
…		…
1375		1709
1376	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
1377	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,
1378	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,
1379	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,
1380	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>
1381	delaying any later requests for a long time.	1715	requests, delaying any later requests for a long time.
1382		1716
1383	To avoid this, and allow incremental generation of requests, you can	1717	To avoid this, and allow incremental generation of requests, you can
1384	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
1385	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>,
1386	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
…		…
1435		1769
1436	See C<poll_cb> for an example.	1770	See C<poll_cb> for an example.
1437		1771
1438	=item IO::AIO::poll_cb	1772	=item IO::AIO::poll_cb
1439		1773
1440	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
1441	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
1442	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
1443	reason. Returns immediately when no events are outstanding. The amount of	1780	reason. Returns immediately when no events are outstanding. The amount
1444	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>,
1445	C<IO::AIO::max_poll_time>.	1782	C<IO::AIO::max_poll_time> and C<IO::AIO::max_outstanding>.
1446		1783
1447	If not all requests were processed for whatever reason, the filehandle	1784	If not all requests were processed for whatever reason, the poll file
1448	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
1449	do anything special to have it called later.	1786	don't have to do anything special to have it called later.
1450		1787
1451	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
1452	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
1453	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
1454	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
…		…
1463	poll => 'r', async => 1,	1800	poll => 'r', async => 1,
1464	cb => \&IO::AIO::poll_cb);	1801	cb => \&IO::AIO::poll_cb);
1465		1802
1466	=item IO::AIO::poll_wait	1803	=item IO::AIO::poll_wait
1467		1804
1468	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
1469	phase, wait till the result filehandle becomes ready for reading (simply	1806	requests are outstanding anymore.
1470	does a C<select> on the filehandle. This is useful if you want to	1807
1471	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.
1472		1810
1473	See C<nreqs> for an example.	1811	See C<nreqs> for an example.
1474		1812
1475	=item IO::AIO::poll	1813	=item IO::AIO::poll
1476		1814
…		…
1665		2003
1666	=item IO::AIO::fadvise $fh, $offset, $len, $advice	2004	=item IO::AIO::fadvise $fh, $offset, $len, $advice
1667		2005
1668	Simply calls the C<posix_fadvise> function (see its	2006	Simply calls the C<posix_fadvise> function (see its
1669	manpage for details). The following advice constants are	2007	manpage for details). The following advice constants are
1670	avaiable: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>,	2008	available: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>,
1671	C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>,	2009	C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>,
1672	C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>.	2010	C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>.
1673		2011
1674	On systems that do not implement C<posix_fadvise>, this function returns	2012	On systems that do not implement C<posix_fadvise>, this function returns
1675	ENOSYS, otherwise the return value of C<posix_fadvise>.	2013	ENOSYS, otherwise the return value of C<posix_fadvise>.
1676		2014
1677	=item IO::AIO::madvise $scalar, $offset, $len, $advice	2015	=item IO::AIO::madvise $scalar, $offset, $len, $advice
1678		2016
1679	Simply calls the C<posix_madvise> function (see its	2017	Simply calls the C<posix_madvise> function (see its
1680	manpage for details). The following advice constants are	2018	manpage for details). The following advice constants are
1681	avaiable: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,	2019	available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,
1682	C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>.	2020	C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>.
1683		2021
1684	On systems that do not implement C<posix_madvise>, this function returns	2022	On systems that do not implement C<posix_madvise>, this function returns
1685	ENOSYS, otherwise the return value of C<posix_madvise>.	2023	ENOSYS, otherwise the return value of C<posix_madvise>.
1686		2024
1687	=item IO::AIO::mprotect $scalar, $offset, $len, $protect	2025	=item IO::AIO::mprotect $scalar, $offset, $len, $protect
1688		2026
1689	Simply calls the C<mprotect> function on the preferably AIO::mmap'ed	2027	Simply calls the C<mprotect> function on the preferably AIO::mmap'ed
1690	$scalar (see its manpage for details). The following protect	2028	$scalar (see its manpage for details). The following protect
1691	constants are avaiable: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,	2029	constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,
1692	C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.	2030	C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.
1693		2031
1694	On systems that do not implement C<mprotect>, this function returns	2032	On systems that do not implement C<mprotect>, this function returns
1695	ENOSYS, otherwise the return value of C<mprotect>.	2033	ENOSYS, otherwise the return value of C<mprotect>.
1696		2034
1697	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]	2035	=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]
1698		2036
1699	Memory-maps a file (or anonymous memory range) and attaches it to the	2037	Memory-maps a file (or anonymous memory range) and attaches it to the
1700	given C<$scalar>, which will act like a string scalar.	2038	given C<$scalar>, which will act like a string scalar. Returns true on
		2039	success, and false otherwise.
1701		2040
1702	The only operations allowed on the scalar are C<substr>/C<vec> that don't	2041	The only operations allowed on the scalar are C<substr>/C<vec> that don't
1703	change the string length, and most read-only operations such as copying it	2042	change the string length, and most read-only operations such as copying it
1704	or searching it with regexes and so on.	2043	or searching it with regexes and so on.
1705		2044
…		…
1758	Calls the C<munlockall> function.	2097	Calls the C<munlockall> function.
1759		2098
1760	On systems that do not implement C<munlockall>, this function returns	2099	On systems that do not implement C<munlockall>, this function returns
1761	ENOSYS, otherwise the return value of C<munlockall>.	2100	ENOSYS, otherwise the return value of C<munlockall>.
1762		2101
		2102	=item IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags
		2103
		2104	Calls the GNU/Linux C<splice(2)> syscall, if available. If C<$r_off> or
		2105	C<$w_off> are C<undef>, then C<NULL> is passed for these, otherwise they
		2106	should be the file offset.
		2107
		2108	C<$r_fh> and C<$w_fh> should not refer to the same file, as splice might
		2109	silently corrupt the data in this case.
		2110
		2111	The following symbol flag values are available: C<IO::AIO::SPLICE_F_MOVE>,
		2112	C<IO::AIO::SPLICE_F_NONBLOCK>, C<IO::AIO::SPLICE_F_MORE> and
		2113	C<IO::AIO::SPLICE_F_GIFT>.
		2114
		2115	See the C<splice(2)> manpage for details.
		2116
		2117	=item IO::AIO::tee $r_fh, $w_fh, $length, $flags
		2118
		2119	Calls the GNU/Linux C<tee(2)> syscall, see it's manpage and the
		2120	description for C<IO::AIO::splice> above for details.
		2121
1763	=back	2122	=back
1764		2123
1765	=cut	2124	=cut
1766		2125
1767	min_parallel 8;	2126	min_parallel 8;
…		…
1804	=head2 FORK BEHAVIOUR	2163	=head2 FORK BEHAVIOUR
1805		2164
1806	Usage of pthreads in a program changes the semantics of fork	2165	Usage of pthreads in a program changes the semantics of fork
1807	considerably. Specifically, only async-safe functions can be called after	2166	considerably. Specifically, only async-safe functions can be called after
1808	fork. Perl doesn't know about this, so in general, you cannot call fork	2167	fork. Perl doesn't know about this, so in general, you cannot call fork
1809	with defined behaviour in perl. IO::AIO uses pthreads, so this applies,	2168	with defined behaviour in perl if pthreads are involved. IO::AIO uses
1810	but many other extensions and (for inexplicable reasons) perl itself often	2169	pthreads, so this applies, but many other extensions and (for inexplicable
1811	is linked against pthreads, so this limitation applies.	2170	reasons) perl itself often is linked against pthreads, so this limitation
		2171	applies to quite a lot of perls.
1812		2172
1813	Some operating systems have extensions that allow safe use of fork, and	2173	This module no longer tries to fight your OS, or POSIX. That means IO::AIO
1814	this module should do "the right thing" on those, and tries on others. At	2174	only works in the process that loaded it. Forking is fully supported, but
1815	the time of this writing (2011) only GNU/Linux supports these extensions	2175	using IO::AIO in the child is not.
1816	to POSIX.	2176
		2177	You might get around by not I<using> IO::AIO before (or after)
		2178	forking. You could also try to call the L<IO::AIO::reinit> function in the
		2179	child:
		2180
		2181	=over 4
		2182
		2183	=item IO::AIO::reinit
		2184
		2185	Abandons all current requests and I/O threads and simply reinitialises all
		2186	data structures. This is not an operation supported by any standards, but
		2187	happens to work on GNU/Linux and some newer BSD systems.
		2188
		2189	The only reasonable use for this function is to call it after forking, if
		2190	C<IO::AIO> was used in the parent. Calling it while IO::AIO is active in
		2191	the process will result in undefined behaviour. Calling it at any time
		2192	will also result in any undefined (by POSIX) behaviour.
		2193
		2194	=back
1817		2195
1818	=head2 MEMORY USAGE	2196	=head2 MEMORY USAGE
1819		2197
1820	Per-request usage:	2198	Per-request usage:
1821		2199

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Comparing IO-AIO/AIO.pm (file contents): Revision 1.203 by root, Thu Jul 7 22:36:18 2011 UTC vs. Revision 1.242 by root, Sun Jan 6 11:48:13 2013 UTC

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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.203 by root, Thu Jul 7 22:36:18 2011 UTC vs.
Revision 1.242 by root, Sun Jan 6 11:48:13 2013 UTC