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

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.274 by root, Thu Sep 21 23:43:46 2017 UTC vs.
Revision 1.309 by root, Tue Dec 29 15:20:12 2020 UTC

…		…
171	use common::sense;	171	use common::sense;
172		172
173	use base 'Exporter';	173	use base 'Exporter';
174		174
175	BEGIN {	175	BEGIN {
176	our $VERSION = 4.35;	176	our $VERSION = 4.74;
177		177
178	our @AIO_REQ = qw(aio_sendfile aio_seek aio_read aio_write aio_open aio_close	178	our @AIO_REQ = qw(aio_sendfile aio_seek aio_read aio_write aio_open aio_close
179	aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx	179	aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx
180	aio_scandir aio_symlink aio_readlink aio_realpath aio_fcntl aio_ioctl	180	aio_scandir aio_symlink aio_readlink aio_realpath aio_fcntl aio_ioctl
181	aio_sync aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range	181	aio_sync aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range
…		…
183	aio_rename aio_rename2 aio_link aio_move aio_copy aio_group	183	aio_rename aio_rename2 aio_link aio_move aio_copy aio_group
184	aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown	184	aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown
185	aio_chmod aio_utime aio_truncate	185	aio_chmod aio_utime aio_truncate
186	aio_msync aio_mtouch aio_mlock aio_mlockall	186	aio_msync aio_mtouch aio_mlock aio_mlockall
187	aio_statvfs	187	aio_statvfs
		188	aio_slurp
188	aio_wd);	189	aio_wd);
189		190
190	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));	191	our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));
191	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush	192	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush
192	min_parallel max_parallel max_idle idle_timeout	193	min_parallel max_parallel max_idle idle_timeout
193	nreqs nready npending nthreads	194	nreqs nready npending nthreads
194	max_poll_time max_poll_reqs	195	max_poll_time max_poll_reqs
195	sendfile fadvise madvise	196	sendfile fadvise madvise
196	mmap munmap munlock munlockall);	197	mmap munmap mremap munlock munlockall);
197		198
198	push @AIO_REQ, qw(aio_busy); # not exported	199	push @AIO_REQ, qw(aio_busy); # not exported
199		200
200	@IO::AIO::GRP::ISA = 'IO::AIO::REQ';	201	@IO::AIO::GRP::ISA = 'IO::AIO::REQ';
201		202
…		…
277	IO::AIO::idle_timeout $seconds	278	IO::AIO::idle_timeout $seconds
278	IO::AIO::max_outstanding $maxreqs	279	IO::AIO::max_outstanding $maxreqs
279	IO::AIO::nreqs	280	IO::AIO::nreqs
280	IO::AIO::nready	281	IO::AIO::nready
281	IO::AIO::npending	282	IO::AIO::npending
		283	IO::AIO::reinit
		284
		285	$nfd = IO::AIO::get_fdlimit
		286	IO::AIO::min_fdlimit $nfd
282		287
283	IO::AIO::sendfile $ofh, $ifh, $offset, $count	288	IO::AIO::sendfile $ofh, $ifh, $offset, $count
284	IO::AIO::fadvise $fh, $offset, $len, $advice	289	IO::AIO::fadvise $fh, $offset, $len, $advice
		290
285	IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]]	291	IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]]
286	IO::AIO::munmap $scalar	292	IO::AIO::munmap $scalar
		293	IO::AIO::mremap $scalar, $new_length, $flags[, $new_address]
287	IO::AIO::madvise $scalar, $offset, $length, $advice	294	IO::AIO::madvise $scalar, $offset, $length, $advice
288	IO::AIO::mprotect $scalar, $offset, $length, $protect	295	IO::AIO::mprotect $scalar, $offset, $length, $protect
289	IO::AIO::munlock $scalar, $offset = 0, $length = undef	296	IO::AIO::munlock $scalar, $offset = 0, $length = undef
290	IO::AIO::munlockall	297	IO::AIO::munlockall
		298
		299	# stat extensions
		300	$counter = IO::AIO::st_gen
		301	$seconds = IO::AIO::st_atime, IO::AIO::st_mtime, IO::AIO::st_ctime, IO::AIO::st_btime
		302	($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtime
		303	$nanoseconds = IO::AIO::st_atimensec, IO::AIO::st_mtimensec, IO::AIO::st_ctimensec, IO::AIO::st_btimensec
		304	$seconds = IO::AIO::st_btimesec
		305	($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtimensec
		306
		307	# very much unportable syscalls
		308	IO::AIO::accept4 $r_fh, $sockaddr, $sockaddr_len, $flags
		309	IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags
		310	IO::AIO::tee $r_fh, $w_fh, $length, $flags
		311	$actual_size = IO::AIO::pipesize $r_fh[, $new_size]
		312	($rfh, $wfh) = IO::AIO::pipe2 [$flags]
		313	$fh = IO::AIO::memfd_create $pathname[, $flags]
		314	$fh = IO::AIO::eventfd [$initval, [$flags]]
		315	$fh = IO::AIO::timerfd_create $clockid[, $flags]
		316	($cur_interval, $cur_value) = IO::AIO::timerfd_settime $fh, $flags, $new_interval, $nbw_value
		317	($cur_interval, $cur_value) = IO::AIO::timerfd_gettime $fh
291		318
292	=head2 API NOTES	319	=head2 API NOTES
293		320
294	All the C<aio_*> calls are more or less thin wrappers around the syscall	321	All the C<aio_*> calls are more or less thin wrappers around the syscall
295	with the same name (sans C<aio_>). The arguments are similar or identical,	322	with the same name (sans C<aio_>). The arguments are similar or identical,
…		…
401	following POSIX and non-POSIX constants are available (missing ones on	428	following POSIX and non-POSIX constants are available (missing ones on
402	your system are, as usual, C<0>):	429	your system are, as usual, C<0>):
403		430
404	C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,	431	C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,
405	C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>,	432	C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>,
406	C<O_RSYNC>, C<O_SYNC>, C<O_PATH>, C<O_TMPFILE>, and C<O_TTY_INIT>.	433	C<O_RSYNC>, C<O_SYNC>, C<O_PATH>, C<O_TMPFILE>, C<O_TTY_INIT> and C<O_ACCMODE>.
407		434
408		435
409	=item aio_close $fh, $callback->($status)	436	=item aio_close $fh, $callback->($status)
410		437
411	Asynchronously close a file and call the callback with the result	438	Asynchronously close a file and call the callback with the result
…		…
537		564
538	=item aio_stat $fh_or_path, $callback->($status)	565	=item aio_stat $fh_or_path, $callback->($status)
539		566
540	=item aio_lstat $fh, $callback->($status)	567	=item aio_lstat $fh, $callback->($status)
541		568
542	Works like perl's C<stat> or C<lstat> in void context. The callback will	569	Works almost exactly like perl's C<stat> or C<lstat> in void context. The
543	be called after the stat and the results will be available using C<stat _>	570	callback will be called after the stat and the results will be available
544	or C<-s _> etc...	571	using C<stat _> or C<-s _> and other tests (with the exception of C<-B>
		572	and C<-T>).
545		573
546	The pathname passed to C<aio_stat> must be absolute. See API NOTES, above,	574	The pathname passed to C<aio_stat> must be absolute. See API NOTES, above,
547	for an explanation.	575	for an explanation.
548		576
549	Currently, the stats are always 64-bit-stats, i.e. instead of returning an	577	Currently, the stats are always 64-bit-stats, i.e. instead of returning an
…		…
556	behaviour).	584	behaviour).
557		585
558	C<S_IFMT>, C<S_IFIFO>, C<S_IFCHR>, C<S_IFBLK>, C<S_IFLNK>, C<S_IFREG>,	586	C<S_IFMT>, C<S_IFIFO>, C<S_IFCHR>, C<S_IFBLK>, C<S_IFLNK>, C<S_IFREG>,
559	C<S_IFDIR>, C<S_IFWHT>, C<S_IFSOCK>, C<IO::AIO::major $dev_t>,	587	C<S_IFDIR>, C<S_IFWHT>, C<S_IFSOCK>, C<IO::AIO::major $dev_t>,
560	C<IO::AIO::minor $dev_t>, C<IO::AIO::makedev $major, $minor>.	588	C<IO::AIO::minor $dev_t>, C<IO::AIO::makedev $major, $minor>.
		589
		590	To access higher resolution stat timestamps, see L<SUBSECOND STAT TIME
		591	ACCESS>.
561		592
562	Example: Print the length of F</etc/passwd>:	593	Example: Print the length of F</etc/passwd>:
563		594
564	aio_stat "/etc/passwd", sub {	595	aio_stat "/etc/passwd", sub {
565	$_[0] and die "stat failed: $!";	596	$_[0] and die "stat failed: $!";
…		…
609	namemax => 255,	640	namemax => 255,
610	frsize => 1024,	641	frsize => 1024,
611	fsid => 1810	642	fsid => 1810
612	}	643	}
613		644
614	Here is a (likely partial - send me updates!) list of fsid values used by
615	Linux - it is safe to hardcode these when C<$^O> is C<linux>:
616
617	0x0000adf5 adfs
618	0x0000adff affs
619	0x5346414f afs
620	0x09041934 anon-inode filesystem
621	0x00000187 autofs
622	0x42465331 befs
623	0x1badface bfs
624	0x42494e4d binfmt_misc
625	0x9123683e btrfs
626	0x0027e0eb cgroupfs
627	0xff534d42 cifs
628	0x73757245 coda
629	0x012ff7b7 coh
630	0x28cd3d45 cramfs
631	0x453dcd28 cramfs-wend (wrong endianness)
632	0x64626720 debugfs
633	0x00001373 devfs
634	0x00001cd1 devpts
635	0x0000f15f ecryptfs
636	0x00414a53 efs
637	0x0000137d ext
638	0x0000ef53 ext2/ext3/ext4
639	0x0000ef51 ext2
640	0xf2f52010 f2fs
641	0x00004006 fat
642	0x65735546 fuseblk
643	0x65735543 fusectl
644	0x0bad1dea futexfs
645	0x01161970 gfs2
646	0x47504653 gpfs
647	0x00004244 hfs
648	0xf995e849 hpfs
649	0x00c0ffee hostfs
650	0x958458f6 hugetlbfs
651	0x2bad1dea inotifyfs
652	0x00009660 isofs
653	0x000072b6 jffs2
654	0x3153464a jfs
655	0x6b414653 k-afs
656	0x0bd00bd0 lustre
657	0x0000137f minix
658	0x0000138f minix 30 char names
659	0x00002468 minix v2
660	0x00002478 minix v2 30 char names
661	0x00004d5a minix v3
662	0x19800202 mqueue
663	0x00004d44 msdos
664	0x0000564c novell
665	0x00006969 nfs
666	0x6e667364 nfsd
667	0x00003434 nilfs
668	0x5346544e ntfs
669	0x00009fa1 openprom
670	0x7461636F ocfs2
671	0x00009fa0 proc
672	0x6165676c pstorefs
673	0x0000002f qnx4
674	0x68191122 qnx6
675	0x858458f6 ramfs
676	0x52654973 reiserfs
677	0x00007275 romfs
678	0x67596969 rpc_pipefs
679	0x73636673 securityfs
680	0xf97cff8c selinux
681	0x0000517b smb
682	0x534f434b sockfs
683	0x73717368 squashfs
684	0x62656572 sysfs
685	0x012ff7b6 sysv2
686	0x012ff7b5 sysv4
687	0x01021994 tmpfs
688	0x15013346 udf
689	0x00011954 ufs
690	0x54190100 ufs byteswapped
691	0x00009fa2 usbdevfs
692	0x01021997 v9fs
693	0xa501fcf5 vxfs
694	0xabba1974 xenfs
695	0x012ff7b4 xenix
696	0x58465342 xfs
697	0x012fd16d xia
698
699	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)	645	=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
700		646
701	Works like perl's C<utime> function (including the special case of $atime	647	Works like perl's C<utime> function (including the special case of $atime
702	and $mtime being undef). Fractional times are supported if the underlying	648	and $mtime being undef). Fractional times are supported if the underlying
703	syscalls support them.	649	syscalls support them.
704		650
705	When called with a pathname, uses utimes(2) if available, otherwise	651	When called with a pathname, uses utimensat(2) or utimes(2) if available,
706	utime(2). If called on a file descriptor, uses futimes(2) if available,	652	otherwise utime(2). If called on a file descriptor, uses futimens(2)
707	otherwise returns ENOSYS, so this is not portable.	653	or futimes(2) if available, otherwise returns ENOSYS, so this is not
		654	portable.
708		655
709	Examples:	656	Examples:
710		657
711	# set atime and mtime to current time (basically touch(1)):	658	# set atime and mtime to current time (basically touch(1)):
712	aio_utime "path", undef, undef;	659	aio_utime "path", undef, undef;
…		…
871		818
872	=over 4	819	=over 4
873		820
874	=item IO::AIO::READDIR_DENTS	821	=item IO::AIO::READDIR_DENTS
875		822
876	When this flag is off, then the callback gets an arrayref consisting of	823	Normally the callback gets an arrayref consisting of names only (as
877	names only (as with C<aio_readdir>), otherwise it gets an arrayref with	824	with C<aio_readdir>). If this flag is set, then the callback gets an
878	C<[$name, $type, $inode]> arrayrefs, each describing a single directory	825	arrayref with C<[$name, $type, $inode]> arrayrefs, each describing a
879	entry in more detail.	826	single directory entry in more detail:
880		827
881	C<$name> is the name of the entry.	828	C<$name> is the name of the entry.
882		829
883	C<$type> is one of the C<IO::AIO::DT_xxx> constants:	830	C<$type> is one of the C<IO::AIO::DT_xxx> constants:
884		831
885	C<IO::AIO::DT_UNKNOWN>, C<IO::AIO::DT_FIFO>, C<IO::AIO::DT_CHR>, C<IO::AIO::DT_DIR>,	832	C<IO::AIO::DT_UNKNOWN>, C<IO::AIO::DT_FIFO>, C<IO::AIO::DT_CHR>, C<IO::AIO::DT_DIR>,
886	C<IO::AIO::DT_BLK>, C<IO::AIO::DT_REG>, C<IO::AIO::DT_LNK>, C<IO::AIO::DT_SOCK>,	833	C<IO::AIO::DT_BLK>, C<IO::AIO::DT_REG>, C<IO::AIO::DT_LNK>, C<IO::AIO::DT_SOCK>,
887	C<IO::AIO::DT_WHT>.	834	C<IO::AIO::DT_WHT>.
888		835
889	C<IO::AIO::DT_UNKNOWN> means just that: readdir does not know. If you need to	836	C<IO::AIO::DT_UNKNOWN> means just that: readdir does not know. If you need
890	know, you have to run stat yourself. Also, for speed reasons, the C<$type>	837	to know, you have to run stat yourself. Also, for speed/memory reasons,
891	scalars are read-only: you can not modify them.	838	the C<$type> scalars are read-only: you must not modify them.
892		839
893	C<$inode> is the inode number (which might not be exact on systems with 64	840	C<$inode> is the inode number (which might not be exact on systems with 64
894	bit inode numbers and 32 bit perls). This field has unspecified content on	841	bit inode numbers and 32 bit perls). This field has unspecified content on
895	systems that do not deliver the inode information.	842	systems that do not deliver the inode information.
896		843
…		…
907	short names are tried first.	854	short names are tried first.
908		855
909	=item IO::AIO::READDIR_STAT_ORDER	856	=item IO::AIO::READDIR_STAT_ORDER
910		857
911	When this flag is set, then the names will be returned in an order	858	When this flag is set, then the names will be returned in an order
912	suitable for stat()'ing each one. That is, when you plan to stat()	859	suitable for stat()'ing each one. That is, when you plan to stat() most or
913	all files in the given directory, then the returned order will likely	860	all files in the given directory, then the returned order will likely be
914	be fastest.	861	faster.
915		862
916	If both this flag and C<IO::AIO::READDIR_DIRS_FIRST> are specified, then	863	If both this flag and C<IO::AIO::READDIR_DIRS_FIRST> are specified,
917	the likely dirs come first, resulting in a less optimal stat order.	864	then the likely dirs come first, resulting in a less optimal stat order
		865	for stat'ing all entries, but likely a more optimal order for finding
		866	subdirectories.
918		867
919	=item IO::AIO::READDIR_FOUND_UNKNOWN	868	=item IO::AIO::READDIR_FOUND_UNKNOWN
920		869
921	This flag should not be set when calling C<aio_readdirx>. Instead, it	870	This flag should not be set when calling C<aio_readdirx>. Instead, it
922	is being set by C<aio_readdirx>, when any of the C<$type>'s found were	871	is being set by C<aio_readdirx>, when any of the C<$type>'s found were
…		…
924	C<$type>'s are known, which can be used to speed up some algorithms.	873	C<$type>'s are known, which can be used to speed up some algorithms.
925		874
926	=back	875	=back
927		876
928		877
		878	=item aio_slurp $pathname, $offset, $length, $data, $callback->($status)
		879
		880	Opens, reads and closes the given file. The data is put into C<$data>,
		881	which is resized as required.
		882
		883	If C<$offset> is negative, then it is counted from the end of the file.
		884
		885	If C<$length> is zero, then the remaining length of the file is
		886	used. Also, in this case, the same limitations to modifying C<$data> apply
		887	as when IO::AIO::mmap is used, i.e. it must only be modified in-place
		888	with C<substr>. If the size of the file is known, specifying a non-zero
		889	C<$length> results in a performance advantage.
		890
		891	This request is similar to the older C<aio_load> request, but since it is
		892	a single request, it might be more efficient to use.
		893
		894	Example: load F</etc/passwd> into C<$passwd>.
		895
		896	my $passwd;
		897	aio_slurp "/etc/passwd", 0, 0, $passwd, sub {
		898	$_[0] >= 0
		899	or die "/etc/passwd: $!\n";
		900
		901	printf "/etc/passwd is %d bytes long, and contains:\n", length $passwd;
		902	print $passwd;
		903	};
		904	IO::AIO::flush;
		905
		906
929	=item aio_load $pathname, $data, $callback->($status)	907	=item aio_load $pathname, $data, $callback->($status)
930		908
931	This is a composite request that tries to fully load the given file into	909	This is a composite request that tries to fully load the given file into
932	memory. Status is the same as with aio_read.	910	memory. Status is the same as with aio_read.
		911
		912	Using C<aio_slurp> might be more efficient, as it is a single request.
933		913
934	=cut	914	=cut
935		915
936	sub aio_load($$;$) {	916	sub aio_load($$;$) {
937	my ($path, undef, $cb) = @_;	917	my ($path, undef, $cb) = @_;
…		…
957	=item aio_copy $srcpath, $dstpath, $callback->($status)	937	=item aio_copy $srcpath, $dstpath, $callback->($status)
958		938
959	Try to copy the I<file> (directories not supported as either source or	939	Try to copy the I<file> (directories not supported as either source or
960	destination) from C<$srcpath> to C<$dstpath> and call the callback with	940	destination) from C<$srcpath> to C<$dstpath> and call the callback with
961	a status of C<0> (ok) or C<-1> (error, see C<$!>).	941	a status of C<0> (ok) or C<-1> (error, see C<$!>).
		942
		943	Existing destination files will be truncated.
962		944
963	This is a composite request that creates the destination file with	945	This is a composite request that creates the destination file with
964	mode 0200 and copies the contents of the source file into it using	946	mode 0200 and copies the contents of the source file into it using
965	C<aio_sendfile>, followed by restoring atime, mtime, access mode and	947	C<aio_sendfile>, followed by restoring atime, mtime, access mode and
966	uid/gid, in that order.	948	uid/gid, in that order.
…		…
1076	Scans a directory (similar to C<aio_readdir>) but additionally tries to	1058	Scans a directory (similar to C<aio_readdir>) but additionally tries to
1077	efficiently separate the entries of directory C<$path> into two sets of	1059	efficiently separate the entries of directory C<$path> into two sets of
1078	names, directories you can recurse into (directories), and ones you cannot	1060	names, directories you can recurse into (directories), and ones you cannot
1079	recurse into (everything else, including symlinks to directories).	1061	recurse into (everything else, including symlinks to directories).
1080		1062
1081	C<aio_scandir> is a composite request that creates of many sub requests_	1063	C<aio_scandir> is a composite request that generates many sub requests.
1082	C<$maxreq> specifies the maximum number of outstanding aio requests that	1064	C<$maxreq> specifies the maximum number of outstanding aio requests that
1083	this function generates. If it is C<< <= 0 >>, then a suitable default	1065	this function generates. If it is C<< <= 0 >>, then a suitable default
1084	will be chosen (currently 4).	1066	will be chosen (currently 4).
1085		1067
1086	On error, the callback is called without arguments, otherwise it receives	1068	On error, the callback is called without arguments, otherwise it receives
…		…
1150	aioreq_pri $pri;	1132	aioreq_pri $pri;
1151	add $grp aio_stat $wd, sub {	1133	add $grp aio_stat $wd, sub {
1152	return $grp->result () if $_[0];	1134	return $grp->result () if $_[0];
1153	my $now = time;	1135	my $now = time;
1154	my $hash1 = join ":", (stat _)[0,1,3,7,9];	1136	my $hash1 = join ":", (stat _)[0,1,3,7,9];
		1137	my $rdxflags = READDIR_DIRS_FIRST;
		1138
		1139	if ((stat _)[3] < 2) {
		1140	# at least one non-POSIX filesystem exists
		1141	# that returns useful DT_type values: btrfs,
		1142	# so optimise for this here by requesting dents
		1143	$rdxflags \|= READDIR_DENTS;
		1144	}
1155		1145
1156	# read the directory entries	1146	# read the directory entries
1157	aioreq_pri $pri;	1147	aioreq_pri $pri;
1158	add $grp aio_readdirx $wd, READDIR_DIRS_FIRST, sub {	1148	add $grp aio_readdirx $wd, $rdxflags, sub {
1159	my $entries = shift	1149	my ($entries, $flags) = @_
1160	or return $grp->result ();	1150	or return $grp->result ();
		1151
		1152	if ($rdxflags & READDIR_DENTS) {
		1153	# if we requested type values, see if we can use them directly.
		1154
		1155	# if there were any DT_UNKNOWN entries then we assume we
		1156	# don't know. alternatively, we could assume that if we get
		1157	# one DT_DIR, then all directories are indeed marked with
		1158	# DT_DIR, but this seems not required for btrfs, and this
		1159	# is basically the "btrfs can't get it's act together" code
		1160	# branch.
		1161	unless ($flags & READDIR_FOUND_UNKNOWN) {
		1162	# now we have valid DT_ information for all entries,
		1163	# so use it as an optimisation without further stat's.
		1164	# they must also all be at the beginning of @$entries
		1165	# by now.
		1166
		1167	my $dirs;
		1168
		1169	if (@$entries) {
		1170	for (0 .. $#$entries) {
		1171	if ($entries->[$_][1] != DT_DIR) {
		1172	# splice out directories
		1173	$dirs = [splice @$entries, 0, $_];
		1174	last;
		1175	}
		1176	}
		1177
		1178	# if we didn't find any non-dir, then all entries are dirs
		1179	unless ($dirs) {
		1180	($dirs, $entries) = ($entries, []);
		1181	}
		1182	} else {
		1183	# directory is empty, so there are no sbdirs
		1184	$dirs = [];
		1185	}
		1186
		1187	# either splice'd the directories out or the dir was empty.
		1188	# convert dents to filenames
		1189	$_ = $_->[0] for @$dirs;
		1190	$_ = $_->[0] for @$entries;
		1191
		1192	return $grp->result ($dirs, $entries);
		1193	}
		1194
		1195	# cannot use, so return to our old ways
		1196	# by pretending we only scanned for names.
		1197	$_ = $_->[0] for @$entries;
		1198	}
1161		1199
1162	# stat the dir another time	1200	# stat the dir another time
1163	aioreq_pri $pri;	1201	aioreq_pri $pri;
1164	add $grp aio_stat $wd, sub {	1202	add $grp aio_stat $wd, sub {
1165	my $hash2 = join ":", (stat _)[0,1,3,7,9];	1203	my $hash2 = join ":", (stat _)[0,1,3,7,9];
…		…
1271	So in general, you should only use these calls for things that do	1309	So in general, you should only use these calls for things that do
1272	(filesystem) I/O, not for things that wait for other events (network,	1310	(filesystem) I/O, not for things that wait for other events (network,
1273	other processes), although if you are careful and know what you are doing,	1311	other processes), although if you are careful and know what you are doing,
1274	you still can.	1312	you still can.
1275		1313
1276	The following constants are available (missing ones are, as usual C<0>):	1314	The following constants are available and can be used for normal C<ioctl>
		1315	and C<fcntl> as well (missing ones are, as usual C<0>):
1277		1316
1278	C<F_DUPFD_CLOEXEC>,	1317	C<F_DUPFD_CLOEXEC>,
1279		1318
1280	C<F_OFD_GETLK>, C<F_OFD_SETLK>, C<F_OFD_GETLKW>,	1319	C<F_OFD_GETLK>, C<F_OFD_SETLK>, C<F_OFD_GETLKW>,
1281		1320
1282	C<FIFREEZE>, C<FITHAW>, C<FITRIM>, C<FICLONE>, C<FICLONERANGE>, C<FIDEDUPERANGE>.	1321	C<FIFREEZE>, C<FITHAW>, C<FITRIM>, C<FICLONE>, C<FICLONERANGE>, C<FIDEDUPERANGE>.
		1322
		1323	C<F_ADD_SEALS>, C<F_GET_SEALS>, C<F_SEAL_SEAL>, C<F_SEAL_SHRINK>, C<F_SEAL_GROW> and
		1324	C<F_SEAL_WRITE>.
1283		1325
1284	C<FS_IOC_GETFLAGS>, C<FS_IOC_SETFLAGS>, C<FS_IOC_GETVERSION>, C<FS_IOC_SETVERSION>,	1326	C<FS_IOC_GETFLAGS>, C<FS_IOC_SETFLAGS>, C<FS_IOC_GETVERSION>, C<FS_IOC_SETVERSION>,
1285	C<FS_IOC_FIEMAP>.	1327	C<FS_IOC_FIEMAP>.
1286		1328
1287	C<FS_IOC_FSGETXATTR>, C<FS_IOC_FSSETXATTR>, C<FS_IOC_SET_ENCRYPTION_POLICY>,	1329	C<FS_IOC_FSGETXATTR>, C<FS_IOC_FSSETXATTR>, C<FS_IOC_SET_ENCRYPTION_POLICY>,
…		…
1426	IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh;	1468	IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh;
1427	aio_mlock $data; # mlock in background	1469	aio_mlock $data; # mlock in background
1428		1470
1429	=item aio_mlockall $flags, $callback->($status)	1471	=item aio_mlockall $flags, $callback->($status)
1430		1472
1431	Calls the C<mlockall> function with the given C<$flags> (a combination of	1473	Calls the C<mlockall> function with the given C<$flags> (a
1432	C<IO::AIO::MCL_CURRENT> and C<IO::AIO::MCL_FUTURE>).	1474	combination of C<IO::AIO::MCL_CURRENT>, C<IO::AIO::MCL_FUTURE> and
		1475	C<IO::AIO::MCL_ONFAULT>).
1433		1476
1434	On systems that do not implement C<mlockall>, this function returns C<-1>	1477	On systems that do not implement C<mlockall>, this function returns C<-1>
1435	and sets errno to C<ENOSYS>.	1478	and sets errno to C<ENOSYS>. Similarly, flag combinations not supported
		1479	by the system result in a return value of C<-1> with errno being set to
		1480	C<EINVAL>.
1436		1481
1437	Note that the corresponding C<munlockall> is synchronous and is	1482	Note that the corresponding C<munlockall> is synchronous and is
1438	documented under L<MISCELLANEOUS FUNCTIONS>.	1483	documented under L<MISCELLANEOUS FUNCTIONS>.
1439		1484
1440	Example: asynchronously lock all current and future pages into memory.	1485	Example: asynchronously lock all current and future pages into memory.
…		…
1479	C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>,	1524	C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>,
1480	C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>,	1525	C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>,
1481	C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or	1526	C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or
1482	C<IO::AIO::FIEMAP_EXTENT_SHARED>.	1527	C<IO::AIO::FIEMAP_EXTENT_SHARED>.
1483		1528
1484	At the time of this writing (Linux 3.2), this requets is unreliable unless	1529	At the time of this writing (Linux 3.2), this request is unreliable unless
1485	C<$count> is C<undef>, as the kernel has all sorts of bugs preventing	1530	C<$count> is C<undef>, as the kernel has all sorts of bugs preventing
1486	it to return all extents of a range for files with large number of	1531	it to return all extents of a range for files with a large number of
1487	extents. The code works around all these issues if C<$count> is undef.	1532	extents. The code (only) works around all these issues if C<$count> is
		1533	C<undef>.
1488		1534
1489	=item aio_group $callback->(...)	1535	=item aio_group $callback->(...)
1490		1536
1491	This is a very special aio request: Instead of doing something, it is a	1537	This is a very special aio request: Instead of doing something, it is a
1492	container for other aio requests, which is useful if you want to bundle	1538	container for other aio requests, which is useful if you want to bundle
…		…
1605	There are some caveats: when directories get renamed (or deleted), the	1651	There are some caveats: when directories get renamed (or deleted), the
1606	pathname string doesn't change, so will point to the new directory (or	1652	pathname string doesn't change, so will point to the new directory (or
1607	nowhere at all), while the directory fd, if available on the system,	1653	nowhere at all), while the directory fd, if available on the system,
1608	will still point to the original directory. Most functions accepting a	1654	will still point to the original directory. Most functions accepting a
1609	pathname will use the directory fd on newer systems, and the string on	1655	pathname will use the directory fd on newer systems, and the string on
1610	older systems. Some functions (such as realpath) will always rely on the	1656	older systems. Some functions (such as C<aio_realpath>) will always rely on
1611	string form of the pathname.	1657	the string form of the pathname.
1612		1658
1613	So this functionality is mainly useful to get some protection against	1659	So this functionality is mainly useful to get some protection against
1614	C<chdir>, to easily get an absolute path out of a relative path for future	1660	C<chdir>, to easily get an absolute path out of a relative path for future
1615	reference, and to speed up doing many operations in the same directory	1661	reference, and to speed up doing many operations in the same directory
1616	(e.g. when stat'ing all files in a directory).	1662	(e.g. when stat'ing all files in a directory).
…		…
1633	C<aio_wd> callback, as future requests using the value will fail in the	1679	C<aio_wd> callback, as future requests using the value will fail in the
1634	expected way.	1680	expected way.
1635		1681
1636	=item IO::AIO::CWD	1682	=item IO::AIO::CWD
1637		1683
1638	This is a compiletime constant (object) that represents the process	1684	This is a compile time constant (object) that represents the process
1639	current working directory.	1685	current working directory.
1640		1686
1641	Specifying this object as working directory object for a pathname is as if	1687	Specifying this object as working directory object for a pathname is as if
1642	the pathname would be specified directly, without a directory object. For	1688	the pathname would be specified directly, without a directory object. For
1643	example, these calls are functionally identical:	1689	example, these calls are functionally identical:
…		…
1824	The default value for the limit is C<0>, but note that setting a feeder	1870	The default value for the limit is C<0>, but note that setting a feeder
1825	automatically bumps it up to C<2>.	1871	automatically bumps it up to C<2>.
1826		1872
1827	=back	1873	=back
1828		1874
		1875
1829	=head2 SUPPORT FUNCTIONS	1876	=head2 SUPPORT FUNCTIONS
1830		1877
1831	=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION	1878	=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION
1832		1879
1833	=over 4	1880	=over 4
…		…
1898	Strictly equivalent to:	1945	Strictly equivalent to:
1899		1946
1900	IO::AIO::poll_wait, IO::AIO::poll_cb	1947	IO::AIO::poll_wait, IO::AIO::poll_cb
1901	while IO::AIO::nreqs;	1948	while IO::AIO::nreqs;
1902		1949
		1950	This function can be useful at program aborts, to make sure outstanding
		1951	I/O has been done (C<IO::AIO> uses an C<END> block which already calls
		1952	this function on normal exits), or when you are merely using C<IO::AIO>
		1953	for its more advanced functions, rather than for async I/O, e.g.:
		1954
		1955	my ($dirs, $nondirs);
		1956	IO::AIO::aio_scandir "/tmp", 0, sub { ($dirs, $nondirs) = @_ };
		1957	IO::AIO::flush;
		1958	# $dirs, $nondirs are now set
		1959
1903	=item IO::AIO::max_poll_reqs $nreqs	1960	=item IO::AIO::max_poll_reqs $nreqs
1904		1961
1905	=item IO::AIO::max_poll_time $seconds	1962	=item IO::AIO::max_poll_time $seconds
1906		1963
1907	These set the maximum number of requests (default C<0>, meaning infinity)	1964	These set the maximum number of requests (default C<0>, meaning infinity)
…		…
1933	poll => 'r', nice => 1,	1990	poll => 'r', nice => 1,
1934	cb => &IO::AIO::poll_cb);	1991	cb => &IO::AIO::poll_cb);
1935		1992
1936	=back	1993	=back
1937		1994
		1995
1938	=head3 CONTROLLING THE NUMBER OF THREADS	1996	=head3 CONTROLLING THE NUMBER OF THREADS
1939		1997
1940	=over	1998	=over
1941		1999
1942	=item IO::AIO::min_parallel $nthreads	2000	=item IO::AIO::min_parallel $nthreads
…		…
2029	The default value for C<max_outstanding> is very large, so there is no	2087	The default value for C<max_outstanding> is very large, so there is no
2030	practical limit on the number of outstanding requests.	2088	practical limit on the number of outstanding requests.
2031		2089
2032	=back	2090	=back
2033		2091
		2092
2034	=head3 STATISTICAL INFORMATION	2093	=head3 STATISTICAL INFORMATION
2035		2094
2036	=over	2095	=over
2037		2096
2038	=item IO::AIO::nreqs	2097	=item IO::AIO::nreqs
…		…
2054		2113
2055	Returns the number of requests currently in the pending state (executed,	2114	Returns the number of requests currently in the pending state (executed,
2056	but not yet processed by poll_cb).	2115	but not yet processed by poll_cb).
2057		2116
2058	=back	2117	=back
		2118
		2119
		2120	=head3 SUBSECOND STAT TIME ACCESS
		2121
		2122	Both C<aio_stat>/C<aio_lstat> and perl's C<stat>/C<lstat> functions can
		2123	generally find access/modification and change times with subsecond time
		2124	accuracy of the system supports it, but perl's built-in functions only
		2125	return the integer part.
		2126
		2127	The following functions return the timestamps of the most recent
		2128	stat with subsecond precision on most systems and work both after
		2129	C<aio_stat>/C<aio_lstat> and perl's C<stat>/C<lstat> calls. Their return
		2130	value is only meaningful after a successful C<stat>/C<lstat> call, or
		2131	during/after a successful C<aio_stat>/C<aio_lstat> callback.
		2132
		2133	This is similar to the L<Time::HiRes> C<stat> functions, but can return
		2134	full resolution without rounding and work with standard perl C<stat>,
		2135	alleviating the need to call the special C<Time::HiRes> functions, which
		2136	do not act like their perl counterparts.
		2137
		2138	On operating systems or file systems where subsecond time resolution is
		2139	not supported or could not be detected, a fractional part of C<0> is
		2140	returned, so it is always safe to call these functions.
		2141
		2142	=over 4
		2143
		2144	=item $seconds = IO::AIO::st_atime, IO::AIO::st_mtime, IO::AIO::st_ctime, IO::AIO::st_btime
		2145
		2146	Return the access, modication, change or birth time, respectively,
		2147	including fractional part. Due to the limited precision of floating point,
		2148	the accuracy on most platforms is only a bit better than milliseconds
		2149	for times around now - see the I<nsec> function family, below, for full
		2150	accuracy.
		2151
		2152	File birth time is only available when the OS and perl support it (on
		2153	FreeBSD and NetBSD at the time of this writing, although support is
		2154	adaptive, so if your OS/perl gains support, IO::AIO can take advantage of
		2155	it). On systems where it isn't available, C<0> is currently returned, but
		2156	this might change to C<undef> in a future version.
		2157
		2158	=item ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtime
		2159
		2160	Returns access, modification, change and birth time all in one go, and
		2161	maybe more times in the future version.
		2162
		2163	=item $nanoseconds = IO::AIO::st_atimensec, IO::AIO::st_mtimensec, IO::AIO::st_ctimensec, IO::AIO::st_btimensec
		2164
		2165	Return the fractional access, modifcation, change or birth time, in nanoseconds,
		2166	as an integer in the range C<0> to C<999999999>.
		2167
		2168	Note that no accessors are provided for access, modification and
		2169	change times - you need to get those from C<stat _> if required (C<int
		2170	IO::AIO::st_atime> and so on will I<not> generally give you the correct
		2171	value).
		2172
		2173	=item $seconds = IO::AIO::st_btimesec
		2174
		2175	The (integral) seconds part of the file birth time, if available.
		2176
		2177	=item ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtimensec
		2178
		2179	Like the functions above, but returns all four times in one go (and maybe
		2180	more in future versions).
		2181
		2182	=item $counter = IO::AIO::st_gen
		2183
		2184	Returns the generation counter (in practice this is just a random number)
		2185	of the file. This is only available on platforms which have this member in
		2186	their C<struct stat> (most BSDs at the time of this writing) and generally
		2187	only to the root usert. If unsupported, C<0> is returned, but this might
		2188	change to C<undef> in a future version.
		2189
		2190	=back
		2191
		2192	Example: print the high resolution modification time of F</etc>, using
		2193	C<stat>, and C<IO::AIO::aio_stat>.
		2194
		2195	if (stat "/etc") {
		2196	printf "stat(/etc) mtime: %f\n", IO::AIO::st_mtime;
		2197	}
		2198
		2199	IO::AIO::aio_stat "/etc", sub {
		2200	$_[0]
		2201	and return;
		2202
		2203	printf "aio_stat(/etc) mtime: %d.%09d\n", (stat _)[9], IO::AIO::st_mtimensec;
		2204	};
		2205
		2206	IO::AIO::flush;
		2207
		2208	Output of the awbove on my system, showing reduced and full accuracy:
		2209
		2210	stat(/etc) mtime: 1534043702.020808
		2211	aio_stat(/etc) mtime: 1534043702.020807792
		2212
2059		2213
2060	=head3 MISCELLANEOUS FUNCTIONS	2214	=head3 MISCELLANEOUS FUNCTIONS
2061		2215
2062	IO::AIO implements some functions that are useful when you want to use	2216	IO::AIO implements some functions that are useful when you want to use
2063	some "Advanced I/O" function not available to in Perl, without going the	2217	some "Advanced I/O" function not available to in Perl, without going the
2064	"Asynchronous I/O" route. Many of these have an asynchronous C<aio_*>	2218	"Asynchronous I/O" route. Many of these have an asynchronous C<aio_*>
2065	counterpart.	2219	counterpart.
2066		2220
2067	=over 4	2221	=over 4
		2222
		2223	=item $numfd = IO::AIO::get_fdlimit
		2224
		2225	Tries to find the current file descriptor limit and returns it, or
		2226	C<undef> and sets C<$!> in case of an error. The limit is one larger than
		2227	the highest valid file descriptor number.
		2228
		2229	=item IO::AIO::min_fdlimit [$numfd]
		2230
		2231	Try to increase the current file descriptor limit(s) to at least C<$numfd>
		2232	by changing the soft or hard file descriptor resource limit. If C<$numfd>
		2233	is missing, it will try to set a very high limit, although this is not
		2234	recommended when you know the actual minimum that you require.
		2235
		2236	If the limit cannot be raised enough, the function makes a best-effort
		2237	attempt to increase the limit as much as possible, using various
		2238	tricks, while still failing. You can query the resulting limit using
		2239	C<IO::AIO::get_fdlimit>.
		2240
		2241	If an error occurs, returns C<undef> and sets C<$!>, otherwise returns
		2242	true.
2068		2243
2069	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count	2244	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
2070		2245
2071	Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>,	2246	Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>,
2072	but is blocking (this makes most sense if you know the input data is	2247	but is blocking (this makes most sense if you know the input data is
…		…
2179		2354
2180	=item IO::AIO::munmap $scalar	2355	=item IO::AIO::munmap $scalar
2181		2356
2182	Removes a previous mmap and undefines the C<$scalar>.	2357	Removes a previous mmap and undefines the C<$scalar>.
2183		2358
		2359	=item IO::AIO::mremap $scalar, $new_length, $flags = MREMAP_MAYMOVE[, $new_address = 0]
		2360
		2361	Calls the Linux-specific mremap(2) system call. The C<$scalar> must have
		2362	been mapped by C<IO::AIO::mmap>, and C<$flags> must currently either be
		2363	C<0> or C<IO::AIO::MREMAP_MAYMOVE>.
		2364
		2365	Returns true if successful, and false otherwise. If the underlying mmapped
		2366	region has changed address, then the true value has the numerical value
		2367	C<1>, otherwise it has the numerical value C<0>:
		2368
		2369	my $success = IO::AIO::mremap $mmapped, 8192, IO::AIO::MREMAP_MAYMOVE
		2370	or die "mremap: $!";
		2371
		2372	if ($success*1) {
		2373	warn "scalar has chanegd address in memory\n";
		2374	}
		2375
		2376	C<IO::AIO::MREMAP_FIXED> and the C<$new_address> argument are currently
		2377	implemented, but not supported and might go away in a future version.
		2378
		2379	On systems where this call is not supported or is not emulated, this call
		2380	returns falls and sets C<$!> to C<ENOSYS>.
		2381
		2382	=item IO::AIO::mlockall $flags
		2383
		2384	Calls the C<eio_mlockall_sync> function, which is like C<aio_mlockall>,
		2385	but is blocking.
		2386
2184	=item IO::AIO::munlock $scalar, $offset = 0, $length = undef	2387	=item IO::AIO::munlock $scalar, $offset = 0, $length = undef
2185		2388
2186	Calls the C<munlock> function, undoing the effects of a previous	2389	Calls the C<munlock> function, undoing the effects of a previous
2187	C<aio_mlock> call (see its description for details).	2390	C<aio_mlock> call (see its description for details).
2188		2391
…		…
2190		2393
2191	Calls the C<munlockall> function.	2394	Calls the C<munlockall> function.
2192		2395
2193	On systems that do not implement C<munlockall>, this function returns	2396	On systems that do not implement C<munlockall>, this function returns
2194	ENOSYS, otherwise the return value of C<munlockall>.	2397	ENOSYS, otherwise the return value of C<munlockall>.
		2398
		2399	=item $fh = IO::AIO::accept4 $r_fh, $sockaddr, $sockaddr_maxlen, $flags
		2400
		2401	Uses the GNU/Linux C<accept4(2)> syscall, if available, to accept a socket
		2402	and return the new file handle on success, or sets C<$!> and returns
		2403	C<undef> on error.
		2404
		2405	The remote name of the new socket will be stored in C<$sockaddr>, which
		2406	will be extended to allow for at least C<$sockaddr_maxlen> octets. If the
		2407	socket name does not fit into C<$sockaddr_maxlen> octets, this is signaled
		2408	by returning a longer string in C<$sockaddr>, which might or might not be
		2409	truncated.
		2410
		2411	To accept name-less sockets, use C<undef> for C<$sockaddr> and C<0> for
		2412	C<$sockaddr_maxlen>.
		2413
		2414	The main reasons to use this syscall rather than portable C<accept(2)>
		2415	are that you can specify C<SOCK_NONBLOCK> and/or C<SOCK_CLOEXEC>
		2416	flags and you can accept name-less sockets by specifying C<0> for
		2417	C<$sockaddr_maxlen>, which is sadly not possible with perl's interface to
		2418	C<accept>.
2195		2419
2196	=item IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags	2420	=item IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags
2197		2421
2198	Calls the GNU/Linux C<splice(2)> syscall, if available. If C<$r_off> or	2422	Calls the GNU/Linux C<splice(2)> syscall, if available. If C<$r_off> or
2199	C<$w_off> are C<undef>, then C<NULL> is passed for these, otherwise they	2423	C<$w_off> are C<undef>, then C<NULL> is passed for these, otherwise they
…		…
2237	C<$flags> is non-zero, fails with C<ENOSYS>.	2461	C<$flags> is non-zero, fails with C<ENOSYS>.
2238		2462
2239	Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the	2463	Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the
2240	time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and	2464	time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and
2241	C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported.	2465	C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported.
		2466
		2467	Example: create a pipe race-free w.r.t. threads and fork:
		2468
		2469	my ($rfh, $wfh) = IO::AIO::pipe2 IO::AIO::O_CLOEXEC
		2470	or die "pipe2: $!\n";
		2471
		2472	=item $fh = IO::AIO::memfd_create $pathname[, $flags]
		2473
		2474	This is a direct interface to the Linux L<memfd_create(2)> system
		2475	call. The (unhelpful) default for C<$flags> is C<0>, but your default
		2476	should be C<IO::AIO::MFD_CLOEXEC>.
		2477
		2478	On success, the new memfd filehandle is returned, otherwise returns
		2479	C<undef>. If the memfd_create syscall is missing, fails with C<ENOSYS>.
		2480
		2481	Please refer to L<memfd_create(2)> for more info on this call.
		2482
		2483	The following C<$flags> values are available: C<IO::AIO::MFD_CLOEXEC>,
		2484	C<IO::AIO::MFD_ALLOW_SEALING> and C<IO::AIO::MFD_HUGETLB>.
		2485
		2486	Example: create a new memfd.
		2487
		2488	my $fh = IO::AIO::memfd_create "somenameforprocfd", IO::AIO::MFD_CLOEXEC
		2489	or die "memfd_create: $!\n";
		2490
		2491	=item $fh = IO::AIO::pidfd_open $pid[, $flags]
		2492
		2493	This is an interface to the Linux L<pidfd_open(2)> system call. The
		2494	default for C<$flags> is C<0>.
		2495
		2496	On success, a new pidfd filehandle is returned (that is already set to
		2497	close-on-exec), otherwise returns C<undef>. If the syscall is missing,
		2498	fails with C<ENOSYS>.
		2499
		2500	Example: open pid 6341 as pidfd.
		2501
		2502	my $fh = IO::AIO::pidfd_open 6341
		2503	or die "pidfd_open: $!\n";
		2504
		2505	=item $status = IO::AIO::pidfd_send_signal $pidfh, $signal[, $siginfo[, $flags]]
		2506
		2507	This is an interface to the Linux L<pidfd_send_signal> system call. The
		2508	default for C<$siginfo> is C<undef> and the default for C<$flags> is C<0>.
		2509
		2510	Returns the system call status. If the syscall is missing, fails with
		2511	C<ENOSYS>.
		2512
		2513	When specified, C<$siginfo> must be a reference to a hash with one or more
		2514	of the following members:
		2515
		2516	=over
		2517
		2518	=item code - the C<si_code> member
		2519
		2520	=item pid - the C<si_pid> member
		2521
		2522	=item uid - the C<si_uid> member
		2523
		2524	=item value_int - the C<si_value.sival_int> member
		2525
		2526	=item value_ptr - the C<si_value.sival_ptr> member, specified as an integer
		2527
		2528	=back
		2529
		2530	Example: send a SIGKILL to the specified process.
		2531
		2532	my $status = IO::AIO::pidfd_send_signal $pidfh, 9, undef
		2533	and die "pidfd_send_signal: $!\n";
		2534
		2535	Example: send a SIGKILL to the specified process with extra data.
		2536
		2537	my $status = IO::AIO::pidfd_send_signal $pidfh, 9, { code => -1, value_int => 7 }
		2538	and die "pidfd_send_signal: $!\n";
		2539
		2540	=item $fh = IO::AIO::pidfd_getfd $pidfh, $targetfd[, $flags]
		2541
		2542	This is an interface to the Linux L<pidfd_getfd> system call. The default
		2543	for C<$flags> is C<0>.
		2544
		2545	On success, returns a dup'ed copy of the target file descriptor (specified
		2546	as an integer) returned (that is already set to close-on-exec), otherwise
		2547	returns C<undef>. If the syscall is missing, fails with C<ENOSYS>.
		2548
		2549	Example: get a copy of standard error of another process and print soemthing to it.
		2550
		2551	my $errfh = IO::AIO::pidfd_getfd $pidfh, 2
		2552	or die "pidfd_getfd: $!\n";
		2553	print $errfh "stderr\n";
		2554
		2555	=item $fh = IO::AIO::eventfd [$initval, [$flags]]
		2556
		2557	This is a direct interface to the Linux L<eventfd(2)> system call. The
		2558	(unhelpful) defaults for C<$initval> and C<$flags> are C<0> for both.
		2559
		2560	On success, the new eventfd filehandle is returned, otherwise returns
		2561	C<undef>. If the eventfd syscall is missing, fails with C<ENOSYS>.
		2562
		2563	Please refer to L<eventfd(2)> for more info on this call.
		2564
		2565	The following symbol flag values are available: C<IO::AIO::EFD_CLOEXEC>,
		2566	C<IO::AIO::EFD_NONBLOCK> and C<IO::AIO::EFD_SEMAPHORE> (Linux 2.6.30).
		2567
		2568	Example: create a new eventfd filehandle:
		2569
		2570	$fh = IO::AIO::eventfd 0, IO::AIO::EFD_CLOEXEC
		2571	or die "eventfd: $!\n";
		2572
		2573	=item $fh = IO::AIO::timerfd_create $clockid[, $flags]
		2574
		2575	This is a direct interface to the Linux L<timerfd_create(2)> system
		2576	call. The (unhelpful) default for C<$flags> is C<0>, but your default
		2577	should be C<IO::AIO::TFD_CLOEXEC>.
		2578
		2579	On success, the new timerfd filehandle is returned, otherwise returns
		2580	C<undef>. If the timerfd_create syscall is missing, fails with C<ENOSYS>.
		2581
		2582	Please refer to L<timerfd_create(2)> for more info on this call.
		2583
		2584	The following C<$clockid> values are
		2585	available: C<IO::AIO::CLOCK_REALTIME>, C<IO::AIO::CLOCK_MONOTONIC>
		2586	C<IO::AIO::CLOCK_CLOCK_BOOTTIME> (Linux 3.15)
		2587	C<IO::AIO::CLOCK_CLOCK_REALTIME_ALARM> (Linux 3.11) and
		2588	C<IO::AIO::CLOCK_CLOCK_BOOTTIME_ALARM> (Linux 3.11).
		2589
		2590	The following C<$flags> values are available (Linux
		2591	2.6.27): C<IO::AIO::TFD_NONBLOCK> and C<IO::AIO::TFD_CLOEXEC>.
		2592
		2593	Example: create a new timerfd and set it to one-second repeated alarms,
		2594	then wait for two alarms:
		2595
		2596	my $fh = IO::AIO::timerfd_create IO::AIO::CLOCK_BOOTTIME, IO::AIO::TFD_CLOEXEC
		2597	or die "timerfd_create: $!\n";
		2598
		2599	defined IO::AIO::timerfd_settime $fh, 0, 1, 1
		2600	or die "timerfd_settime: $!\n";
		2601
		2602	for (1..2) {
		2603	8 == sysread $fh, my $buf, 8
		2604	or die "timerfd read failure\n";
		2605
		2606	printf "number of expirations (likely 1): %d\n",
		2607	unpack "Q", $buf;
		2608	}
		2609
		2610	=item ($cur_interval, $cur_value) = IO::AIO::timerfd_settime $fh, $flags, $new_interval, $nbw_value
		2611
		2612	This is a direct interface to the Linux L<timerfd_settime(2)> system
		2613	call. Please refer to its manpage for more info on this call.
		2614
		2615	The new itimerspec is specified using two (possibly fractional) second
		2616	values, C<$new_interval> and C<$new_value>).
		2617
		2618	On success, the current interval and value are returned (as per
		2619	C<timerfd_gettime>). On failure, the empty list is returned.
		2620
		2621	The following C<$flags> values are
		2622	available: C<IO::AIO::TFD_TIMER_ABSTIME> and
		2623	C<IO::AIO::TFD_TIMER_CANCEL_ON_SET>.
		2624
		2625	See C<IO::AIO::timerfd_create> for a full example.
		2626
		2627	=item ($cur_interval, $cur_value) = IO::AIO::timerfd_gettime $fh
		2628
		2629	This is a direct interface to the Linux L<timerfd_gettime(2)> system
		2630	call. Please refer to its manpage for more info on this call.
		2631
		2632	On success, returns the current values of interval and value for the given
		2633	timerfd (as potentially fractional second values). On failure, the empty
		2634	list is returned.
2242		2635
2243	=back	2636	=back
2244		2637
2245	=cut	2638	=cut
2246		2639
…		…
2312	the process will result in undefined behaviour. Calling it at any time	2705	the process will result in undefined behaviour. Calling it at any time
2313	will also result in any undefined (by POSIX) behaviour.	2706	will also result in any undefined (by POSIX) behaviour.
2314		2707
2315	=back	2708	=back
2316		2709
		2710	=head2 LINUX-SPECIFIC CALLS
		2711
		2712	When a call is documented as "linux-specific" then this means it
		2713	originated on GNU/Linux. C<IO::AIO> will usually try to autodetect the
		2714	availability and compatibility of such calls regardless of the platform
		2715	it is compiled on, so platforms such as FreeBSD which often implement
		2716	these calls will work. When in doubt, call them and see if they fail wth
		2717	C<ENOSYS>.
		2718
2317	=head2 MEMORY USAGE	2719	=head2 MEMORY USAGE
2318		2720
2319	Per-request usage:	2721	Per-request usage:
2320		2722
2321	Each aio request uses - depending on your architecture - around 100-200	2723	Each aio request uses - depending on your architecture - around 100-200
…		…
2333	temporary buffers, and each thread requires a stack and other data	2735	temporary buffers, and each thread requires a stack and other data
2334	structures (usually around 16k-128k, depending on the OS).	2736	structures (usually around 16k-128k, depending on the OS).
2335		2737
2336	=head1 KNOWN BUGS	2738	=head1 KNOWN BUGS
2337		2739
2338	Known bugs will be fixed in the next release.	2740	Known bugs will be fixed in the next release :)
		2741
		2742	=head1 KNOWN ISSUES
		2743
		2744	Calls that try to "import" foreign memory areas (such as C<IO::AIO::mmap>
		2745	or C<IO::AIO::aio_slurp>) do not work with generic lvalues, such as
		2746	non-created hash slots or other scalars I didn't think of. It's best to
		2747	avoid such and either use scalar variables or making sure that the scalar
		2748	exists (e.g. by storing C<undef>) and isn't "funny" (e.g. tied).
		2749
		2750	I am not sure anything can be done about this, so this is considered a
		2751	known issue, rather than a bug.
2339		2752
2340	=head1 SEE ALSO	2753	=head1 SEE ALSO
2341		2754
2342	L<AnyEvent::AIO> for easy integration into event loops, L<Coro::AIO> for a	2755	L<AnyEvent::AIO> for easy integration into event loops, L<Coro::AIO> for a
2343	more natural syntax.	2756	more natural syntax and L<IO::FDPass> for file descriptor passing.
2344		2757
2345	=head1 AUTHOR	2758	=head1 AUTHOR
2346		2759
2347	Marc Lehmann <schmorp@schmorp.de>	2760	Marc Lehmann <schmorp@schmorp.de>
2348	http://home.schmorp.de/	2761	http://home.schmorp.de/

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Comparing IO-AIO/AIO.pm (file contents): Revision 1.274 by root, Thu Sep 21 23:43:46 2017 UTC vs. Revision 1.309 by root, Tue Dec 29 15:20:12 2020 UTC

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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.274 by root, Thu Sep 21 23:43:46 2017 UTC vs.
Revision 1.309 by root, Tue Dec 29 15:20:12 2020 UTC