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

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.281 by root, Tue Feb 20 04:32:59 2018 UTC vs.
Revision 1.318 by root, Sat Apr 1 02:14:05 2023 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 = 4.4;	176	our $VERSION = 4.80;
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
…		…
192	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush	192	our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush
193	min_parallel max_parallel max_idle idle_timeout	193	min_parallel max_parallel max_idle idle_timeout
194	nreqs nready npending nthreads	194	nreqs nready npending nthreads
195	max_poll_time max_poll_reqs	195	max_poll_time max_poll_reqs
196	sendfile fadvise madvise	196	sendfile fadvise madvise
197	mmap munmap munlock munlockall);	197	mmap munmap mremap munlock munlockall
		198
		199	accept4 tee splice pipe2 pipesize
		200	fexecve mount umount memfd_create eventfd
		201	timerfd_create timerfd_settime timerfd_gettime
		202	pidfd_open pidfd_send_signal pidfd_getfd);
198		203
199	push @AIO_REQ, qw(aio_busy); # not exported	204	push @AIO_REQ, qw(aio_busy); # not exported
200		205
201	@IO::AIO::GRP::ISA = 'IO::AIO::REQ';	206	@IO::AIO::GRP::ISA = 'IO::AIO::REQ';
202		207
…		…
278	IO::AIO::idle_timeout $seconds	283	IO::AIO::idle_timeout $seconds
279	IO::AIO::max_outstanding $maxreqs	284	IO::AIO::max_outstanding $maxreqs
280	IO::AIO::nreqs	285	IO::AIO::nreqs
281	IO::AIO::nready	286	IO::AIO::nready
282	IO::AIO::npending	287	IO::AIO::npending
		288	IO::AIO::reinit
		289
283	$nfd = IO::AIO::get_fdlimit [EXPERIMENTAL]	290	$nfd = IO::AIO::get_fdlimit
284	IO::AIO::min_fdlimit $nfd [EXPERIMENTAL]	291	IO::AIO::min_fdlimit $nfd
285		292
286	IO::AIO::sendfile $ofh, $ifh, $offset, $count	293	IO::AIO::sendfile $ofh, $ifh, $offset, $count
287	IO::AIO::fadvise $fh, $offset, $len, $advice	294	IO::AIO::fadvise $fh, $offset, $len, $advice
		295	IO::AIO::fexecve $fh, $argv, $envp
		296
288	IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]]	297	IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]]
289	IO::AIO::munmap $scalar	298	IO::AIO::munmap $scalar
		299	IO::AIO::mremap $scalar, $new_length, $flags[, $new_address]
290	IO::AIO::madvise $scalar, $offset, $length, $advice	300	IO::AIO::madvise $scalar, $offset, $length, $advice
291	IO::AIO::mprotect $scalar, $offset, $length, $protect	301	IO::AIO::mprotect $scalar, $offset, $length, $protect
292	IO::AIO::munlock $scalar, $offset = 0, $length = undef	302	IO::AIO::munlock $scalar, $offset = 0, $length = undef
293	IO::AIO::munlockall	303	IO::AIO::munlockall
		304
		305	# stat extensions
		306	$counter = IO::AIO::st_gen
		307	$seconds = IO::AIO::st_atime, IO::AIO::st_mtime, IO::AIO::st_ctime, IO::AIO::st_btime
		308	($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtime
		309	$nanoseconds = IO::AIO::st_atimensec, IO::AIO::st_mtimensec, IO::AIO::st_ctimensec, IO::AIO::st_btimensec
		310	$seconds = IO::AIO::st_btimesec
		311	($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtimensec
		312
		313	# very much unportable syscalls
		314	IO::AIO::accept4 $r_fh, $sockaddr, $sockaddr_len, $flags
		315	IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags
		316	IO::AIO::tee $r_fh, $w_fh, $length, $flags
		317
		318	$actual_size = IO::AIO::pipesize $r_fh[, $new_size]
		319	($rfh, $wfh) = IO::AIO::pipe2 [$flags]
		320
		321	$fh = IO::AIO::eventfd [$initval, [$flags]]
		322	$fh = IO::AIO::memfd_create $pathname[, $flags]
		323
		324	$fh = IO::AIO::timerfd_create $clockid[, $flags]
		325	($cur_interval, $cur_value) = IO::AIO::timerfd_settime $fh, $flags, $new_interval, $nbw_value
		326	($cur_interval, $cur_value) = IO::AIO::timerfd_gettime $fh
		327
		328	$fh = IO::AIO::pidfd_open $pid[, $flags]
		329	$status = IO::AIO::pidfd_send_signal $pidfh, $signal[, $siginfo[, $flags]]
		330	$fh = IO::AIO::pidfd_getfd $pidfh, $targetfd[, $flags]
		331
		332	$retval = IO::AIO::mount $special, $path, $fstype, $flags = 0, $data = undef
		333	$retval = IO::AIO::umount $path, $flags = 0
294		334
295	=head2 API NOTES	335	=head2 API NOTES
296		336
297	All the C<aio_*> calls are more or less thin wrappers around the syscall	337	All the C<aio_*> calls are more or less thin wrappers around the syscall
298	with the same name (sans C<aio_>). The arguments are similar or identical,	338	with the same name (sans C<aio_>). The arguments are similar or identical,
…		…
373	=item aio_open $pathname, $flags, $mode, $callback->($fh)	413	=item aio_open $pathname, $flags, $mode, $callback->($fh)
374		414
375	Asynchronously open or create a file and call the callback with a newly	415	Asynchronously open or create a file and call the callback with a newly
376	created filehandle for the file (or C<undef> in case of an error).	416	created filehandle for the file (or C<undef> in case of an error).
377		417
378	The pathname passed to C<aio_open> must be absolute. See API NOTES, above,
379	for an explanation.
380
381	The C<$flags> argument is a bitmask. See the C<Fcntl> module for a	418	The C<$flags> argument is a bitmask. See the C<Fcntl> module for a
382	list. They are the same as used by C<sysopen>.	419	list. They are the same as used by C<sysopen>.
383		420
384	Likewise, C<$mode> specifies the mode of the newly created file, if it	421	Likewise, C<$mode> specifies the mode of the newly created file, if it
385	didn't exist and C<O_CREAT> has been given, just like perl's C<sysopen>,	422	didn't exist and C<O_CREAT> has been given, just like perl's C<sysopen>,
…		…
404	following POSIX and non-POSIX constants are available (missing ones on	441	following POSIX and non-POSIX constants are available (missing ones on
405	your system are, as usual, C<0>):	442	your system are, as usual, C<0>):
406		443
407	C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,	444	C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,
408	C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>,	445	C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>,
409	C<O_RSYNC>, C<O_SYNC>, C<O_PATH>, C<O_TMPFILE>, and C<O_TTY_INIT>.	446	C<O_RSYNC>, C<O_SYNC>, C<O_PATH>, C<O_TMPFILE>, C<O_TTY_INIT> and C<O_ACCMODE>.
410		447
411		448
412	=item aio_close $fh, $callback->($status)	449	=item aio_close $fh, $callback->($status)
413		450
414	Asynchronously close a file and call the callback with the result	451	Asynchronously close a file and call the callback with the result
…		…
540		577
541	=item aio_stat $fh_or_path, $callback->($status)	578	=item aio_stat $fh_or_path, $callback->($status)
542		579
543	=item aio_lstat $fh, $callback->($status)	580	=item aio_lstat $fh, $callback->($status)
544		581
545	Works like perl's C<stat> or C<lstat> in void context. The callback will	582	Works almost exactly like perl's C<stat> or C<lstat> in void context. The
546	be called after the stat and the results will be available using C<stat _>	583	callback will be called after the stat and the results will be available
547	or C<-s _> etc...	584	using C<stat _> or C<-s _> and other tests (with the exception of C<-B>
548		585	and C<-T>).
549	The pathname passed to C<aio_stat> must be absolute. See API NOTES, above,
550	for an explanation.
551		586
552	Currently, the stats are always 64-bit-stats, i.e. instead of returning an	587	Currently, the stats are always 64-bit-stats, i.e. instead of returning an
553	error when stat'ing a large file, the results will be silently truncated	588	error when stat'ing a large file, the results will be silently truncated
554	unless perl itself is compiled with large file support.	589	unless perl itself is compiled with large file support.
555		590
…		…
559	behaviour).	594	behaviour).
560		595
561	C<S_IFMT>, C<S_IFIFO>, C<S_IFCHR>, C<S_IFBLK>, C<S_IFLNK>, C<S_IFREG>,	596	C<S_IFMT>, C<S_IFIFO>, C<S_IFCHR>, C<S_IFBLK>, C<S_IFLNK>, C<S_IFREG>,
562	C<S_IFDIR>, C<S_IFWHT>, C<S_IFSOCK>, C<IO::AIO::major $dev_t>,	597	C<S_IFDIR>, C<S_IFWHT>, C<S_IFSOCK>, C<IO::AIO::major $dev_t>,
563	C<IO::AIO::minor $dev_t>, C<IO::AIO::makedev $major, $minor>.	598	C<IO::AIO::minor $dev_t>, C<IO::AIO::makedev $major, $minor>.
		599
		600	To access higher resolution stat timestamps, see L<SUBSECOND STAT TIME
		601	ACCESS>.
564		602
565	Example: Print the length of F</etc/passwd>:	603	Example: Print the length of F</etc/passwd>:
566		604
567	aio_stat "/etc/passwd", sub {	605	aio_stat "/etc/passwd", sub {
568	$_[0] and die "stat failed: $!";	606	$_[0] and die "stat failed: $!";
…		…
618		656
619	Works like perl's C<utime> function (including the special case of $atime	657	Works like perl's C<utime> function (including the special case of $atime
620	and $mtime being undef). Fractional times are supported if the underlying	658	and $mtime being undef). Fractional times are supported if the underlying
621	syscalls support them.	659	syscalls support them.
622		660
623	When called with a pathname, uses utimes(2) if available, otherwise	661	When called with a pathname, uses utimensat(2) or utimes(2) if available,
624	utime(2). If called on a file descriptor, uses futimes(2) if available,	662	otherwise utime(2). If called on a file descriptor, uses futimens(2)
625	otherwise returns ENOSYS, so this is not portable.	663	or futimes(2) if available, otherwise returns ENOSYS, so this is not
		664	portable.
626		665
627	Examples:	666	Examples:
628		667
629	# set atime and mtime to current time (basically touch(1)):	668	# set atime and mtime to current time (basically touch(1)):
630	aio_utime "path", undef, undef;	669	aio_utime "path", undef, undef;
…		…
789		828
790	=over 4	829	=over 4
791		830
792	=item IO::AIO::READDIR_DENTS	831	=item IO::AIO::READDIR_DENTS
793		832
794	When this flag is off, then the callback gets an arrayref consisting of	833	Normally the callback gets an arrayref consisting of names only (as
795	names only (as with C<aio_readdir>), otherwise it gets an arrayref with	834	with C<aio_readdir>). If this flag is set, then the callback gets an
796	C<[$name, $type, $inode]> arrayrefs, each describing a single directory	835	arrayref with C<[$name, $type, $inode]> arrayrefs, each describing a
797	entry in more detail.	836	single directory entry in more detail:
798		837
799	C<$name> is the name of the entry.	838	C<$name> is the name of the entry.
800		839
801	C<$type> is one of the C<IO::AIO::DT_xxx> constants:	840	C<$type> is one of the C<IO::AIO::DT_xxx> constants:
802		841
803	C<IO::AIO::DT_UNKNOWN>, C<IO::AIO::DT_FIFO>, C<IO::AIO::DT_CHR>, C<IO::AIO::DT_DIR>,	842	C<IO::AIO::DT_UNKNOWN>, C<IO::AIO::DT_FIFO>, C<IO::AIO::DT_CHR>, C<IO::AIO::DT_DIR>,
804	C<IO::AIO::DT_BLK>, C<IO::AIO::DT_REG>, C<IO::AIO::DT_LNK>, C<IO::AIO::DT_SOCK>,	843	C<IO::AIO::DT_BLK>, C<IO::AIO::DT_REG>, C<IO::AIO::DT_LNK>, C<IO::AIO::DT_SOCK>,
805	C<IO::AIO::DT_WHT>.	844	C<IO::AIO::DT_WHT>.
806		845
807	C<IO::AIO::DT_UNKNOWN> means just that: readdir does not know. If you need to	846	C<IO::AIO::DT_UNKNOWN> means just that: readdir does not know. If you need
808	know, you have to run stat yourself. Also, for speed reasons, the C<$type>	847	to know, you have to run stat yourself. Also, for speed/memory reasons,
809	scalars are read-only: you can not modify them.	848	the C<$type> scalars are read-only: you must not modify them.
810		849
811	C<$inode> is the inode number (which might not be exact on systems with 64	850	C<$inode> is the inode number (which might not be exact on systems with 64
812	bit inode numbers and 32 bit perls). This field has unspecified content on	851	bit inode numbers and 32 bit perls). This field has unspecified content on
813	systems that do not deliver the inode information.	852	systems that do not deliver the inode information.
814		853
…		…
825	short names are tried first.	864	short names are tried first.
826		865
827	=item IO::AIO::READDIR_STAT_ORDER	866	=item IO::AIO::READDIR_STAT_ORDER
828		867
829	When this flag is set, then the names will be returned in an order	868	When this flag is set, then the names will be returned in an order
830	suitable for stat()'ing each one. That is, when you plan to stat()	869	suitable for stat()'ing each one. That is, when you plan to stat() most or
831	all files in the given directory, then the returned order will likely	870	all files in the given directory, then the returned order will likely be
832	be fastest.	871	faster.
833		872
834	If both this flag and C<IO::AIO::READDIR_DIRS_FIRST> are specified, then	873	If both this flag and C<IO::AIO::READDIR_DIRS_FIRST> are specified,
835	the likely dirs come first, resulting in a less optimal stat order.	874	then the likely dirs come first, resulting in a less optimal stat order
		875	for stat'ing all entries, but likely a more optimal order for finding
		876	subdirectories.
836		877
837	=item IO::AIO::READDIR_FOUND_UNKNOWN	878	=item IO::AIO::READDIR_FOUND_UNKNOWN
838		879
839	This flag should not be set when calling C<aio_readdirx>. Instead, it	880	This flag should not be set when calling C<aio_readdirx>. Instead, it
840	is being set by C<aio_readdirx>, when any of the C<$type>'s found were	881	is being set by C<aio_readdirx>, when any of the C<$type>'s found were
…		…
1101	aioreq_pri $pri;	1142	aioreq_pri $pri;
1102	add $grp aio_stat $wd, sub {	1143	add $grp aio_stat $wd, sub {
1103	return $grp->result () if $_[0];	1144	return $grp->result () if $_[0];
1104	my $now = time;	1145	my $now = time;
1105	my $hash1 = join ":", (stat _)[0,1,3,7,9];	1146	my $hash1 = join ":", (stat _)[0,1,3,7,9];
		1147	my $rdxflags = READDIR_DIRS_FIRST;
		1148
		1149	if ((stat _)[3] < 2) {
		1150	# at least one non-POSIX filesystem exists
		1151	# that returns useful DT_type values: btrfs,
		1152	# so optimise for this here by requesting dents
		1153	$rdxflags \|= READDIR_DENTS;
		1154	}
1106		1155
1107	# read the directory entries	1156	# read the directory entries
1108	aioreq_pri $pri;	1157	aioreq_pri $pri;
1109	add $grp aio_readdirx $wd, READDIR_DIRS_FIRST, sub {	1158	add $grp aio_readdirx $wd, $rdxflags, sub {
1110	my $entries = shift	1159	my ($entries, $flags) = @_
1111	or return $grp->result ();	1160	or return $grp->result ();
		1161
		1162	if ($rdxflags & READDIR_DENTS) {
		1163	# if we requested type values, see if we can use them directly.
		1164
		1165	# if there were any DT_UNKNOWN entries then we assume we
		1166	# don't know. alternatively, we could assume that if we get
		1167	# one DT_DIR, then all directories are indeed marked with
		1168	# DT_DIR, but this seems not required for btrfs, and this
		1169	# is basically the "btrfs can't get it's act together" code
		1170	# branch.
		1171	unless ($flags & READDIR_FOUND_UNKNOWN) {
		1172	# now we have valid DT_ information for all entries,
		1173	# so use it as an optimisation without further stat's.
		1174	# they must also all be at the beginning of @$entries
		1175	# by now.
		1176
		1177	my $dirs;
		1178
		1179	if (@$entries) {
		1180	for (0 .. $#$entries) {
		1181	if ($entries->[$_][1] != DT_DIR) {
		1182	# splice out directories
		1183	$dirs = [splice @$entries, 0, $_];
		1184	last;
		1185	}
		1186	}
		1187
		1188	# if we didn't find any non-dir, then all entries are dirs
		1189	unless ($dirs) {
		1190	($dirs, $entries) = ($entries, []);
		1191	}
		1192	} else {
		1193	# directory is empty, so there are no sbdirs
		1194	$dirs = [];
		1195	}
		1196
		1197	# either splice'd the directories out or the dir was empty.
		1198	# convert dents to filenames
		1199	$_ = $_->[0] for @$dirs;
		1200	$_ = $_->[0] for @$entries;
		1201
		1202	return $grp->result ($dirs, $entries);
		1203	}
		1204
		1205	# cannot use, so return to our old ways
		1206	# by pretending we only scanned for names.
		1207	$_ = $_->[0] for @$entries;
		1208	}
1112		1209
1113	# stat the dir another time	1210	# stat the dir another time
1114	aioreq_pri $pri;	1211	aioreq_pri $pri;
1115	add $grp aio_stat $wd, sub {	1212	add $grp aio_stat $wd, sub {
1116	my $hash2 = join ":", (stat _)[0,1,3,7,9];	1213	my $hash2 = join ":", (stat _)[0,1,3,7,9];
…		…
1222	So in general, you should only use these calls for things that do	1319	So in general, you should only use these calls for things that do
1223	(filesystem) I/O, not for things that wait for other events (network,	1320	(filesystem) I/O, not for things that wait for other events (network,
1224	other processes), although if you are careful and know what you are doing,	1321	other processes), although if you are careful and know what you are doing,
1225	you still can.	1322	you still can.
1226		1323
1227	The following constants are available (missing ones are, as usual C<0>):	1324	The following constants are available and can be used for normal C<ioctl>
		1325	and C<fcntl> as well (missing ones are, as usual C<0>):
1228		1326
1229	C<F_DUPFD_CLOEXEC>,	1327	C<F_DUPFD_CLOEXEC>,
1230		1328
1231	C<F_OFD_GETLK>, C<F_OFD_SETLK>, C<F_OFD_GETLKW>,	1329	C<F_OFD_GETLK>, C<F_OFD_SETLK>, C<F_OFD_GETLKW>,
1232		1330
1233	C<FIFREEZE>, C<FITHAW>, C<FITRIM>, C<FICLONE>, C<FICLONERANGE>, C<FIDEDUPERANGE>.	1331	C<FIFREEZE>, C<FITHAW>, C<FITRIM>, C<FICLONE>, C<FICLONERANGE>, C<FIDEDUPERANGE>.
		1332
		1333	C<F_ADD_SEALS>, C<F_GET_SEALS>, C<F_SEAL_SEAL>, C<F_SEAL_SHRINK>, C<F_SEAL_GROW> and
		1334	C<F_SEAL_WRITE>.
1234		1335
1235	C<FS_IOC_GETFLAGS>, C<FS_IOC_SETFLAGS>, C<FS_IOC_GETVERSION>, C<FS_IOC_SETVERSION>,	1336	C<FS_IOC_GETFLAGS>, C<FS_IOC_SETFLAGS>, C<FS_IOC_GETVERSION>, C<FS_IOC_SETVERSION>,
1236	C<FS_IOC_FIEMAP>.	1337	C<FS_IOC_FIEMAP>.
1237		1338
1238	C<FS_IOC_FSGETXATTR>, C<FS_IOC_FSSETXATTR>, C<FS_IOC_SET_ENCRYPTION_POLICY>,	1339	C<FS_IOC_FSGETXATTR>, C<FS_IOC_FSSETXATTR>, C<FS_IOC_SET_ENCRYPTION_POLICY>,
…		…
1246		1347
1247	C<FS_XFLAG_REALTIME>, C<FS_XFLAG_PREALLOC>, C<FS_XFLAG_IMMUTABLE>, C<FS_XFLAG_APPEND>,	1348	C<FS_XFLAG_REALTIME>, C<FS_XFLAG_PREALLOC>, C<FS_XFLAG_IMMUTABLE>, C<FS_XFLAG_APPEND>,
1248	C<FS_XFLAG_SYNC>, C<FS_XFLAG_NOATIME>, C<FS_XFLAG_NODUMP>, C<FS_XFLAG_RTINHERIT>,	1349	C<FS_XFLAG_SYNC>, C<FS_XFLAG_NOATIME>, C<FS_XFLAG_NODUMP>, C<FS_XFLAG_RTINHERIT>,
1249	C<FS_XFLAG_PROJINHERIT>, C<FS_XFLAG_NOSYMLINKS>, C<FS_XFLAG_EXTSIZE>, C<FS_XFLAG_EXTSZINHERIT>,	1350	C<FS_XFLAG_PROJINHERIT>, C<FS_XFLAG_NOSYMLINKS>, C<FS_XFLAG_EXTSIZE>, C<FS_XFLAG_EXTSZINHERIT>,
1250	C<FS_XFLAG_NODEFRAG>, C<FS_XFLAG_FILESTREAM>, C<FS_XFLAG_DAX>, C<FS_XFLAG_HASATTR>,	1351	C<FS_XFLAG_NODEFRAG>, C<FS_XFLAG_FILESTREAM>, C<FS_XFLAG_DAX>, C<FS_XFLAG_HASATTR>,
		1352
		1353	C<BLKROSET>, C<BLKROGET>, C<BLKRRPART>, C<BLKGETSIZE>, C<BLKFLSBUF>, C<BLKRASET>,
		1354	C<BLKRAGET>, C<BLKFRASET>, C<BLKFRAGET>, C<BLKSECTSET>, C<BLKSECTGET>, C<BLKSSZGET>,
		1355	C<BLKBSZGET>, C<BLKBSZSET>, C<BLKGETSIZE64>,
		1356
1251		1357
1252	=item aio_sync $callback->($status)	1358	=item aio_sync $callback->($status)
1253		1359
1254	Asynchronously call sync and call the callback when finished.	1360	Asynchronously call sync and call the callback when finished.
1255		1361
…		…
1377	IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh;	1483	IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh;
1378	aio_mlock $data; # mlock in background	1484	aio_mlock $data; # mlock in background
1379		1485
1380	=item aio_mlockall $flags, $callback->($status)	1486	=item aio_mlockall $flags, $callback->($status)
1381		1487
1382	Calls the C<mlockall> function with the given C<$flags> (a combination of	1488	Calls the C<mlockall> function with the given C<$flags> (a
1383	C<IO::AIO::MCL_CURRENT> and C<IO::AIO::MCL_FUTURE>).	1489	combination of C<IO::AIO::MCL_CURRENT>, C<IO::AIO::MCL_FUTURE> and
		1490	C<IO::AIO::MCL_ONFAULT>).
1384		1491
1385	On systems that do not implement C<mlockall>, this function returns C<-1>	1492	On systems that do not implement C<mlockall>, this function returns C<-1>
1386	and sets errno to C<ENOSYS>.	1493	and sets errno to C<ENOSYS>. Similarly, flag combinations not supported
		1494	by the system result in a return value of C<-1> with errno being set to
		1495	C<EINVAL>.
1387		1496
1388	Note that the corresponding C<munlockall> is synchronous and is	1497	Note that the corresponding C<munlockall> is synchronous and is
1389	documented under L<MISCELLANEOUS FUNCTIONS>.	1498	documented under L<MISCELLANEOUS FUNCTIONS>.
1390		1499
1391	Example: asynchronously lock all current and future pages into memory.	1500	Example: asynchronously lock all current and future pages into memory.
…		…
1585	C<aio_wd> callback, as future requests using the value will fail in the	1694	C<aio_wd> callback, as future requests using the value will fail in the
1586	expected way.	1695	expected way.
1587		1696
1588	=item IO::AIO::CWD	1697	=item IO::AIO::CWD
1589		1698
1590	This is a compiletime constant (object) that represents the process	1699	This is a compile time constant (object) that represents the process
1591	current working directory.	1700	current working directory.
1592		1701
1593	Specifying this object as working directory object for a pathname is as if	1702	Specifying this object as working directory object for a pathname is as if
1594	the pathname would be specified directly, without a directory object. For	1703	the pathname would be specified directly, without a directory object. For
1595	example, these calls are functionally identical:	1704	example, these calls are functionally identical:
…		…
1776	The default value for the limit is C<0>, but note that setting a feeder	1885	The default value for the limit is C<0>, but note that setting a feeder
1777	automatically bumps it up to C<2>.	1886	automatically bumps it up to C<2>.
1778		1887
1779	=back	1888	=back
1780		1889
		1890
1781	=head2 SUPPORT FUNCTIONS	1891	=head2 SUPPORT FUNCTIONS
1782		1892
1783	=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION	1893	=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION
1784		1894
1785	=over 4	1895	=over 4
…		…
1850	Strictly equivalent to:	1960	Strictly equivalent to:
1851		1961
1852	IO::AIO::poll_wait, IO::AIO::poll_cb	1962	IO::AIO::poll_wait, IO::AIO::poll_cb
1853	while IO::AIO::nreqs;	1963	while IO::AIO::nreqs;
1854		1964
		1965	This function can be useful at program aborts, to make sure outstanding
		1966	I/O has been done (C<IO::AIO> uses an C<END> block which already calls
		1967	this function on normal exits), or when you are merely using C<IO::AIO>
		1968	for its more advanced functions, rather than for async I/O, e.g.:
		1969
		1970	my ($dirs, $nondirs);
		1971	IO::AIO::aio_scandir "/tmp", 0, sub { ($dirs, $nondirs) = @_ };
		1972	IO::AIO::flush;
		1973	# $dirs, $nondirs are now set
		1974
1855	=item IO::AIO::max_poll_reqs $nreqs	1975	=item IO::AIO::max_poll_reqs $nreqs
1856		1976
1857	=item IO::AIO::max_poll_time $seconds	1977	=item IO::AIO::max_poll_time $seconds
1858		1978
1859	These set the maximum number of requests (default C<0>, meaning infinity)	1979	These set the maximum number of requests (default C<0>, meaning infinity)
…		…
1885	poll => 'r', nice => 1,	2005	poll => 'r', nice => 1,
1886	cb => &IO::AIO::poll_cb);	2006	cb => &IO::AIO::poll_cb);
1887		2007
1888	=back	2008	=back
1889		2009
		2010
1890	=head3 CONTROLLING THE NUMBER OF THREADS	2011	=head3 CONTROLLING THE NUMBER OF THREADS
1891		2012
1892	=over	2013	=over
1893		2014
1894	=item IO::AIO::min_parallel $nthreads	2015	=item IO::AIO::min_parallel $nthreads
…		…
1955	longer exceeded.	2076	longer exceeded.
1956		2077
1957	In other words, this setting does not enforce a queue limit, but can be	2078	In other words, this setting does not enforce a queue limit, but can be
1958	used to make poll functions block if the limit is exceeded.	2079	used to make poll functions block if the limit is exceeded.
1959		2080
1960	This is a very bad function to use in interactive programs because it	2081	This is a bad function to use in interactive programs because it blocks,
1961	blocks, and a bad way to reduce concurrency because it is inexact: Better	2082	and a bad way to reduce concurrency because it is inexact. If you need to
		2083	issue many requests without being able to call a poll function on demand,
1962	use an C<aio_group> together with a feed callback.	2084	it is better to use an C<aio_group> together with a feed callback.
1963		2085
1964	Its main use is in scripts without an event loop - when you want to stat	2086	Its main use is in scripts without an event loop - when you want to stat a
1965	a lot of files, you can write something like this:	2087	lot of files, you can write something like this:
1966		2088
1967	IO::AIO::max_outstanding 32;	2089	IO::AIO::max_outstanding 32;
1968		2090
1969	for my $path (...) {	2091	for my $path (...) {
1970	aio_stat $path , ...;	2092	aio_stat $path , ...;
1971	IO::AIO::poll_cb;	2093	IO::AIO::poll_cb;
1972	}	2094	}
1973		2095
1974	IO::AIO::flush;	2096	IO::AIO::flush;
1975		2097
1976	The call to C<poll_cb> inside the loop will normally return instantly, but	2098	The call to C<poll_cb> inside the loop will normally return instantly,
1977	as soon as more thna C<32> reqeusts are in-flight, it will block until	2099	allowing the loop to progress, but as soon as more than C<32> requests
1978	some requests have been handled. This keeps the loop from pushing a large	2100	are in-flight, it will block until some requests have been handled. This
1979	number of C<aio_stat> requests onto the queue.	2101	keeps the loop from pushing a large number of C<aio_stat> requests onto
		2102	the queue (which, with many paths to stat, can use up a lot of memory).
1980		2103
1981	The default value for C<max_outstanding> is very large, so there is no	2104	The default value for C<max_outstanding> is very large, so there is no
1982	practical limit on the number of outstanding requests.	2105	practical limit on the number of outstanding requests.
1983		2106
1984	=back	2107	=back
1985		2108
		2109
1986	=head3 STATISTICAL INFORMATION	2110	=head3 STATISTICAL INFORMATION
1987		2111
1988	=over	2112	=over
1989		2113
1990	=item IO::AIO::nreqs	2114	=item IO::AIO::nreqs
…		…
2006		2130
2007	Returns the number of requests currently in the pending state (executed,	2131	Returns the number of requests currently in the pending state (executed,
2008	but not yet processed by poll_cb).	2132	but not yet processed by poll_cb).
2009		2133
2010	=back	2134	=back
		2135
		2136
		2137	=head3 SUBSECOND STAT TIME ACCESS
		2138
		2139	Both C<aio_stat>/C<aio_lstat> and perl's C<stat>/C<lstat> functions can
		2140	generally find access/modification and change times with subsecond time
		2141	accuracy of the system supports it, but perl's built-in functions only
		2142	return the integer part.
		2143
		2144	The following functions return the timestamps of the most recent
		2145	stat with subsecond precision on most systems and work both after
		2146	C<aio_stat>/C<aio_lstat> and perl's C<stat>/C<lstat> calls. Their return
		2147	value is only meaningful after a successful C<stat>/C<lstat> call, or
		2148	during/after a successful C<aio_stat>/C<aio_lstat> callback.
		2149
		2150	This is similar to the L<Time::HiRes> C<stat> functions, but can return
		2151	full resolution without rounding and work with standard perl C<stat>,
		2152	alleviating the need to call the special C<Time::HiRes> functions, which
		2153	do not act like their perl counterparts.
		2154
		2155	On operating systems or file systems where subsecond time resolution is
		2156	not supported or could not be detected, a fractional part of C<0> is
		2157	returned, so it is always safe to call these functions.
		2158
		2159	=over 4
		2160
		2161	=item $seconds = IO::AIO::st_atime, IO::AIO::st_mtime, IO::AIO::st_ctime, IO::AIO::st_btime
		2162
		2163	Return the access, modication, change or birth time, respectively,
		2164	including fractional part. Due to the limited precision of floating point,
		2165	the accuracy on most platforms is only a bit better than milliseconds
		2166	for times around now - see the I<nsec> function family, below, for full
		2167	accuracy.
		2168
		2169	File birth time is only available when the OS and perl support it (on
		2170	FreeBSD and NetBSD at the time of this writing, although support is
		2171	adaptive, so if your OS/perl gains support, IO::AIO can take advantage of
		2172	it). On systems where it isn't available, C<0> is currently returned, but
		2173	this might change to C<undef> in a future version.
		2174
		2175	=item ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtime
		2176
		2177	Returns access, modification, change and birth time all in one go, and
		2178	maybe more times in the future version.
		2179
		2180	=item $nanoseconds = IO::AIO::st_atimensec, IO::AIO::st_mtimensec, IO::AIO::st_ctimensec, IO::AIO::st_btimensec
		2181
		2182	Return the fractional access, modifcation, change or birth time, in nanoseconds,
		2183	as an integer in the range C<0> to C<999999999>.
		2184
		2185	Note that no accessors are provided for access, modification and
		2186	change times - you need to get those from C<stat _> if required (C<int
		2187	IO::AIO::st_atime> and so on will I<not> generally give you the correct
		2188	value).
		2189
		2190	=item $seconds = IO::AIO::st_btimesec
		2191
		2192	The (integral) seconds part of the file birth time, if available.
		2193
		2194	=item ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtimensec
		2195
		2196	Like the functions above, but returns all four times in one go (and maybe
		2197	more in future versions).
		2198
		2199	=item $counter = IO::AIO::st_gen
		2200
		2201	Returns the generation counter (in practice this is just a random number)
		2202	of the file. This is only available on platforms which have this member in
		2203	their C<struct stat> (most BSDs at the time of this writing) and generally
		2204	only to the root usert. If unsupported, C<0> is returned, but this might
		2205	change to C<undef> in a future version.
		2206
		2207	=back
		2208
		2209	Example: print the high resolution modification time of F</etc>, using
		2210	C<stat>, and C<IO::AIO::aio_stat>.
		2211
		2212	if (stat "/etc") {
		2213	printf "stat(/etc) mtime: %f\n", IO::AIO::st_mtime;
		2214	}
		2215
		2216	IO::AIO::aio_stat "/etc", sub {
		2217	$_[0]
		2218	and return;
		2219
		2220	printf "aio_stat(/etc) mtime: %d.%09d\n", (stat _)[9], IO::AIO::st_mtimensec;
		2221	};
		2222
		2223	IO::AIO::flush;
		2224
		2225	Output of the awbove on my system, showing reduced and full accuracy:
		2226
		2227	stat(/etc) mtime: 1534043702.020808
		2228	aio_stat(/etc) mtime: 1534043702.020807792
		2229
2011		2230
2012	=head3 MISCELLANEOUS FUNCTIONS	2231	=head3 MISCELLANEOUS FUNCTIONS
2013		2232
2014	IO::AIO implements some functions that are useful when you want to use	2233	IO::AIO implements some functions that are useful when you want to use
2015	some "Advanced I/O" function not available to in Perl, without going the	2234	some "Advanced I/O" function not available to in Perl, without going the
2016	"Asynchronous I/O" route. Many of these have an asynchronous C<aio_*>	2235	"Asynchronous I/O" route. Many of these have an asynchronous C<aio_*>
2017	counterpart.	2236	counterpart.
2018		2237
2019	=over 4	2238	=over 4
2020		2239
		2240	=item $retval = IO::AIO::fexecve $fh, $argv, $envp
		2241
		2242	A more-or-less direct equivalent to the POSIX C<fexecve> functions, which
		2243	allows you to specify the program to be executed via a file descriptor (or
		2244	handle). Returns C<-1> and sets errno to C<ENOSYS> if not available.
		2245
		2246	=item $retval = IO::AIO::mount $special, $path, $fstype, $flags = 0, $data = undef
		2247
		2248	Calls the GNU/Linux mount syscall with the given arguments. All except
		2249	C<$flags> are strings, and if C<$data> is C<undef>, a C<NULL> will be
		2250	passed.
		2251
		2252	The following values for C<$flags> are available:
		2253
		2254	C<IO::AIO::MS_RDONLY>, C<IO::AIO::MS_NOSUID>, C<IO::AIO::MS_NODEV>, C<IO::AIO::MS_NOEXEC>, C<IO::AIO::MS_SYNCHRONOUS>,
		2255	C<IO::AIO::MS_REMOUNT>, C<IO::AIO::MS_MANDLOCK>, C<IO::AIO::MS_DIRSYNC>, C<IO::AIO::MS_NOATIME>,
		2256	C<IO::AIO::MS_NODIRATIME>, C<IO::AIO::MS_BIND>, C<IO::AIO::MS_MOVE>, C<IO::AIO::MS_REC>, C<IO::AIO::MS_SILENT>,
		2257	C<IO::AIO::MS_POSIXACL>, C<IO::AIO::MS_UNBINDABLE>, C<IO::AIO::MS_PRIVATE>, C<IO::AIO::MS_SLAVE>, C<IO::AIO::MS_SHARED>,
		2258	C<IO::AIO::MS_RELATIME>, C<IO::AIO::MS_KERNMOUNT>, C<IO::AIO::MS_I_VERSION>, C<IO::AIO::MS_STRICTATIME>,
		2259	C<IO::AIO::MS_LAZYTIME>, C<IO::AIO::MS_ACTIVE>, C<IO::AIO::MS_NOUSER>, C<IO::AIO::MS_RMT_MASK>, C<IO::AIO::MS_MGC_VAL> and
		2260	C<IO::AIO::MS_MGC_MSK>.
		2261
		2262	=item $retval = IO::AIO::umount $path, $flags = 0
		2263
		2264	Invokes the GNU/Linux C<umount> or C<umount2> syscalls. Always calls
		2265	C<umount> if C<$flags> is C<0>, otherwqise always tries to call
		2266	C<umount2>.
		2267
		2268	The following C<$flags> are available:
		2269
		2270	C<IO::AIO::MNT_FORCE>, C<IO::AIO::MNT_DETACH>, C<IO::AIO::MNT_EXPIRE> and C<IO::AIO::UMOUNT_NOFOLLOW>.
		2271
2021	=item $numfd = IO::AIO::get_fdlimit	2272	=item $numfd = IO::AIO::get_fdlimit
2022
2023	This function is I<EXPERIMENTAL> and subject to change.
2024		2273
2025	Tries to find the current file descriptor limit and returns it, or	2274	Tries to find the current file descriptor limit and returns it, or
2026	C<undef> and sets C<$!> in case of an error. The limit is one larger than	2275	C<undef> and sets C<$!> in case of an error. The limit is one larger than
2027	the highest valid file descriptor number.	2276	the highest valid file descriptor number.
2028		2277
2029	=item IO::AIO::min_fdlimit [$numfd]	2278	=item IO::AIO::min_fdlimit [$numfd]
2030
2031	This function is I<EXPERIMENTAL> and subject to change.
2032		2279
2033	Try to increase the current file descriptor limit(s) to at least C<$numfd>	2280	Try to increase the current file descriptor limit(s) to at least C<$numfd>
2034	by changing the soft or hard file descriptor resource limit. If C<$numfd>	2281	by changing the soft or hard file descriptor resource limit. If C<$numfd>
2035	is missing, it will try to set a very high limit, although this is not	2282	is missing, it will try to set a very high limit, although this is not
2036	recommended when you know the actual minimum that you require.	2283	recommended when you know the actual minimum that you require.
…		…
2131	C<IO::AIO::MAP_POPULATE>,	2378	C<IO::AIO::MAP_POPULATE>,
2132	C<IO::AIO::MAP_NONBLOCK>,	2379	C<IO::AIO::MAP_NONBLOCK>,
2133	C<IO::AIO::MAP_FIXED>,	2380	C<IO::AIO::MAP_FIXED>,
2134	C<IO::AIO::MAP_GROWSDOWN>,	2381	C<IO::AIO::MAP_GROWSDOWN>,
2135	C<IO::AIO::MAP_32BIT>,	2382	C<IO::AIO::MAP_32BIT>,
2136	C<IO::AIO::MAP_HUGETLB> or	2383	C<IO::AIO::MAP_HUGETLB>,
2137	C<IO::AIO::MAP_STACK>.	2384	C<IO::AIO::MAP_STACK>,
		2385	C<IO::AIO::MAP_FIXED_NOREPLACE>,
		2386	C<IO::AIO::MAP_SHARED_VALIDATE>,
		2387	C<IO::AIO::MAP_SYNC> or
		2388	C<IO::AIO::MAP_UNINITIALIZED>.
2138		2389
2139	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.	2390	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.
2140		2391
2141	C<$offset> is the offset from the start of the file - it generally must be	2392	C<$offset> is the offset from the start of the file - it generally must be
2142	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.	2393	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.
…		…
2156		2407
2157	=item IO::AIO::munmap $scalar	2408	=item IO::AIO::munmap $scalar
2158		2409
2159	Removes a previous mmap and undefines the C<$scalar>.	2410	Removes a previous mmap and undefines the C<$scalar>.
2160		2411
		2412	=item IO::AIO::mremap $scalar, $new_length, $flags = MREMAP_MAYMOVE[, $new_address = 0]
		2413
		2414	Calls the Linux-specific mremap(2) system call. The C<$scalar> must have
		2415	been mapped by C<IO::AIO::mmap>, and C<$flags> must currently either be
		2416	C<0> or C<IO::AIO::MREMAP_MAYMOVE>.
		2417
		2418	Returns true if successful, and false otherwise. If the underlying mmapped
		2419	region has changed address, then the true value has the numerical value
		2420	C<1>, otherwise it has the numerical value C<0>:
		2421
		2422	my $success = IO::AIO::mremap $mmapped, 8192, IO::AIO::MREMAP_MAYMOVE
		2423	or die "mremap: $!";
		2424
		2425	if ($success*1) {
		2426	warn "scalar has chanegd address in memory\n";
		2427	}
		2428
		2429	C<IO::AIO::MREMAP_FIXED> and the C<$new_address> argument are currently
		2430	implemented, but not supported and might go away in a future version.
		2431
		2432	On systems where this call is not supported or is not emulated, this call
		2433	returns falls and sets C<$!> to C<ENOSYS>.
		2434
		2435	=item IO::AIO::mlockall $flags
		2436
		2437	Calls the C<eio_mlockall_sync> function, which is like C<aio_mlockall>,
		2438	but is blocking.
		2439
2161	=item IO::AIO::munlock $scalar, $offset = 0, $length = undef	2440	=item IO::AIO::munlock $scalar, $offset = 0, $length = undef
2162		2441
2163	Calls the C<munlock> function, undoing the effects of a previous	2442	Calls the C<munlock> function, undoing the effects of a previous
2164	C<aio_mlock> call (see its description for details).	2443	C<aio_mlock> call (see its description for details).
2165		2444
…		…
2167		2446
2168	Calls the C<munlockall> function.	2447	Calls the C<munlockall> function.
2169		2448
2170	On systems that do not implement C<munlockall>, this function returns	2449	On systems that do not implement C<munlockall>, this function returns
2171	ENOSYS, otherwise the return value of C<munlockall>.	2450	ENOSYS, otherwise the return value of C<munlockall>.
		2451
		2452	=item $fh = IO::AIO::accept4 $r_fh, $sockaddr, $sockaddr_maxlen, $flags
		2453
		2454	Uses the GNU/Linux C<accept4(2)> syscall, if available, to accept a socket
		2455	and return the new file handle on success, or sets C<$!> and returns
		2456	C<undef> on error.
		2457
		2458	The remote name of the new socket will be stored in C<$sockaddr>, which
		2459	will be extended to allow for at least C<$sockaddr_maxlen> octets. If the
		2460	socket name does not fit into C<$sockaddr_maxlen> octets, this is signaled
		2461	by returning a longer string in C<$sockaddr>, which might or might not be
		2462	truncated.
		2463
		2464	To accept name-less sockets, use C<undef> for C<$sockaddr> and C<0> for
		2465	C<$sockaddr_maxlen>.
		2466
		2467	The main reasons to use this syscall rather than portable C<accept(2)>
		2468	are that you can specify C<SOCK_NONBLOCK> and/or C<SOCK_CLOEXEC>
		2469	flags and you can accept name-less sockets by specifying C<0> for
		2470	C<$sockaddr_maxlen>, which is sadly not possible with perl's interface to
		2471	C<accept>.
2172		2472
2173	=item IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags	2473	=item IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags
2174		2474
2175	Calls the GNU/Linux C<splice(2)> syscall, if available. If C<$r_off> or	2475	Calls the GNU/Linux C<splice(2)> syscall, if available. If C<$r_off> or
2176	C<$w_off> are C<undef>, then C<NULL> is passed for these, otherwise they	2476	C<$w_off> are C<undef>, then C<NULL> is passed for these, otherwise they
…		…
2220	Example: create a pipe race-free w.r.t. threads and fork:	2520	Example: create a pipe race-free w.r.t. threads and fork:
2221		2521
2222	my ($rfh, $wfh) = IO::AIO::pipe2 IO::AIO::O_CLOEXEC	2522	my ($rfh, $wfh) = IO::AIO::pipe2 IO::AIO::O_CLOEXEC
2223	or die "pipe2: $!\n";	2523	or die "pipe2: $!\n";
2224		2524
		2525	=item $fh = IO::AIO::memfd_create $pathname[, $flags]
		2526
		2527	This is a direct interface to the Linux L<memfd_create(2)> system
		2528	call. The (unhelpful) default for C<$flags> is C<0>, but your default
		2529	should be C<IO::AIO::MFD_CLOEXEC>.
		2530
		2531	On success, the new memfd filehandle is returned, otherwise returns
		2532	C<undef>. If the memfd_create syscall is missing, fails with C<ENOSYS>.
		2533
		2534	Please refer to L<memfd_create(2)> for more info on this call.
		2535
		2536	The following C<$flags> values are available: C<IO::AIO::MFD_CLOEXEC>,
		2537	C<IO::AIO::MFD_ALLOW_SEALING>, C<IO::AIO::MFD_HUGETLB>,
		2538	C<IO::AIO::MFD_HUGETLB_2MB> and C<IO::AIO::MFD_HUGETLB_1GB>.
		2539
		2540	Example: create a new memfd.
		2541
		2542	my $fh = IO::AIO::memfd_create "somenameforprocfd", IO::AIO::MFD_CLOEXEC
		2543	or die "memfd_create: $!\n";
		2544
		2545	=item $fh = IO::AIO::pidfd_open $pid[, $flags]
		2546
		2547	This is an interface to the Linux L<pidfd_open(2)> system call. The
		2548	default for C<$flags> is C<0>.
		2549
		2550	On success, a new pidfd filehandle is returned (that is already set to
		2551	close-on-exec), otherwise returns C<undef>. If the syscall is missing,
		2552	fails with C<ENOSYS>.
		2553
		2554	Example: open pid 6341 as pidfd.
		2555
		2556	my $fh = IO::AIO::pidfd_open 6341
		2557	or die "pidfd_open: $!\n";
		2558
		2559	=item $status = IO::AIO::pidfd_send_signal $pidfh, $signal[, $siginfo[, $flags]]
		2560
		2561	This is an interface to the Linux L<pidfd_send_signal> system call. The
		2562	default for C<$siginfo> is C<undef> and the default for C<$flags> is C<0>.
		2563
		2564	Returns the system call status. If the syscall is missing, fails with
		2565	C<ENOSYS>.
		2566
		2567	When specified, C<$siginfo> must be a reference to a hash with one or more
		2568	of the following members:
		2569
		2570	=over
		2571
		2572	=item code - the C<si_code> member
		2573
		2574	=item pid - the C<si_pid> member
		2575
		2576	=item uid - the C<si_uid> member
		2577
		2578	=item value_int - the C<si_value.sival_int> member
		2579
		2580	=item value_ptr - the C<si_value.sival_ptr> member, specified as an integer
		2581
		2582	=back
		2583
		2584	Example: send a SIGKILL to the specified process.
		2585
		2586	my $status = IO::AIO::pidfd_send_signal $pidfh, 9, undef
		2587	and die "pidfd_send_signal: $!\n";
		2588
		2589	Example: send a SIGKILL to the specified process with extra data.
		2590
		2591	my $status = IO::AIO::pidfd_send_signal $pidfh, 9, { code => -1, value_int => 7 }
		2592	and die "pidfd_send_signal: $!\n";
		2593
		2594	=item $fh = IO::AIO::pidfd_getfd $pidfh, $targetfd[, $flags]
		2595
		2596	This is an interface to the Linux L<pidfd_getfd> system call. The default
		2597	for C<$flags> is C<0>.
		2598
		2599	On success, returns a dup'ed copy of the target file descriptor (specified
		2600	as an integer) returned (that is already set to close-on-exec), otherwise
		2601	returns C<undef>. If the syscall is missing, fails with C<ENOSYS>.
		2602
		2603	Example: get a copy of standard error of another process and print soemthing to it.
		2604
		2605	my $errfh = IO::AIO::pidfd_getfd $pidfh, 2
		2606	or die "pidfd_getfd: $!\n";
		2607	print $errfh "stderr\n";
		2608
2225	=item $fh = IO::AIO::eventfd ([$initval, [$flags]])	2609	=item $fh = IO::AIO::eventfd [$initval, [$flags]]
2226		2610
2227	This is a direct interface to the Linux L<eventfd(2)> system call. The	2611	This is a direct interface to the Linux L<eventfd(2)> system call. The
2228	(unhelpful) defaults for C<$initval> and C<$flags> are C<0> for both.	2612	(unhelpful) defaults for C<$initval> and C<$flags> are C<0> for both.
2229		2613
2230	On success, the new eventfd filehandle is returned, otherwise returns	2614	On success, the new eventfd filehandle is returned, otherwise returns
…		…
2232		2616
2233	Please refer to L<eventfd(2)> for more info on this call.	2617	Please refer to L<eventfd(2)> for more info on this call.
2234		2618
2235	The following symbol flag values are available: C<IO::AIO::EFD_CLOEXEC>,	2619	The following symbol flag values are available: C<IO::AIO::EFD_CLOEXEC>,
2236	C<IO::AIO::EFD_NONBLOCK> and C<IO::AIO::EFD_SEMAPHORE> (Linux 2.6.30).	2620	C<IO::AIO::EFD_NONBLOCK> and C<IO::AIO::EFD_SEMAPHORE> (Linux 2.6.30).
		2621
		2622	Example: create a new eventfd filehandle:
		2623
		2624	$fh = IO::AIO::eventfd 0, IO::AIO::EFD_CLOEXEC
		2625	or die "eventfd: $!\n";
		2626
		2627	=item $fh = IO::AIO::timerfd_create $clockid[, $flags]
		2628
		2629	This is a direct interface to the Linux L<timerfd_create(2)> system
		2630	call. The (unhelpful) default for C<$flags> is C<0>, but your default
		2631	should be C<IO::AIO::TFD_CLOEXEC>.
		2632
		2633	On success, the new timerfd filehandle is returned, otherwise returns
		2634	C<undef>. If the timerfd_create syscall is missing, fails with C<ENOSYS>.
		2635
		2636	Please refer to L<timerfd_create(2)> for more info on this call.
		2637
		2638	The following C<$clockid> values are
		2639	available: C<IO::AIO::CLOCK_REALTIME>, C<IO::AIO::CLOCK_MONOTONIC>
		2640	C<IO::AIO::CLOCK_CLOCK_BOOTTIME> (Linux 3.15)
		2641	C<IO::AIO::CLOCK_CLOCK_REALTIME_ALARM> (Linux 3.11) and
		2642	C<IO::AIO::CLOCK_CLOCK_BOOTTIME_ALARM> (Linux 3.11).
		2643
		2644	The following C<$flags> values are available (Linux
		2645	2.6.27): C<IO::AIO::TFD_NONBLOCK> and C<IO::AIO::TFD_CLOEXEC>.
		2646
		2647	Example: create a new timerfd and set it to one-second repeated alarms,
		2648	then wait for two alarms:
		2649
		2650	my $fh = IO::AIO::timerfd_create IO::AIO::CLOCK_BOOTTIME, IO::AIO::TFD_CLOEXEC
		2651	or die "timerfd_create: $!\n";
		2652
		2653	defined IO::AIO::timerfd_settime $fh, 0, 1, 1
		2654	or die "timerfd_settime: $!\n";
		2655
		2656	for (1..2) {
		2657	8 == sysread $fh, my $buf, 8
		2658	or die "timerfd read failure\n";
		2659
		2660	printf "number of expirations (likely 1): %d\n",
		2661	unpack "Q", $buf;
		2662	}
		2663
		2664	=item ($cur_interval, $cur_value) = IO::AIO::timerfd_settime $fh, $flags, $new_interval, $nbw_value
		2665
		2666	This is a direct interface to the Linux L<timerfd_settime(2)> system
		2667	call. Please refer to its manpage for more info on this call.
		2668
		2669	The new itimerspec is specified using two (possibly fractional) second
		2670	values, C<$new_interval> and C<$new_value>).
		2671
		2672	On success, the current interval and value are returned (as per
		2673	C<timerfd_gettime>). On failure, the empty list is returned.
		2674
		2675	The following C<$flags> values are
		2676	available: C<IO::AIO::TFD_TIMER_ABSTIME> and
		2677	C<IO::AIO::TFD_TIMER_CANCEL_ON_SET>.
		2678
		2679	See C<IO::AIO::timerfd_create> for a full example.
		2680
		2681	=item ($cur_interval, $cur_value) = IO::AIO::timerfd_gettime $fh
		2682
		2683	This is a direct interface to the Linux L<timerfd_gettime(2)> system
		2684	call. Please refer to its manpage for more info on this call.
		2685
		2686	On success, returns the current values of interval and value for the given
		2687	timerfd (as potentially fractional second values). On failure, the empty
		2688	list is returned.
2237		2689
2238	=back	2690	=back
2239		2691
2240	=cut	2692	=cut
2241		2693
…		…
2307	the process will result in undefined behaviour. Calling it at any time	2759	the process will result in undefined behaviour. Calling it at any time
2308	will also result in any undefined (by POSIX) behaviour.	2760	will also result in any undefined (by POSIX) behaviour.
2309		2761
2310	=back	2762	=back
2311		2763
		2764	=head2 LINUX-SPECIFIC CALLS
		2765
		2766	When a call is documented as "linux-specific" then this means it
		2767	originated on GNU/Linux. C<IO::AIO> will usually try to autodetect the
		2768	availability and compatibility of such calls regardless of the platform
		2769	it is compiled on, so platforms such as FreeBSD which often implement
		2770	these calls will work. When in doubt, call them and see if they fail wth
		2771	C<ENOSYS>.
		2772
2312	=head2 MEMORY USAGE	2773	=head2 MEMORY USAGE
2313		2774
2314	Per-request usage:	2775	Per-request usage:
2315		2776
2316	Each aio request uses - depending on your architecture - around 100-200	2777	Each aio request uses - depending on your architecture - around 100-200
…		…
2328	temporary buffers, and each thread requires a stack and other data	2789	temporary buffers, and each thread requires a stack and other data
2329	structures (usually around 16k-128k, depending on the OS).	2790	structures (usually around 16k-128k, depending on the OS).
2330		2791
2331	=head1 KNOWN BUGS	2792	=head1 KNOWN BUGS
2332		2793
2333	Known bugs will be fixed in the next release.	2794	Known bugs will be fixed in the next release :)
		2795
		2796	=head1 KNOWN ISSUES
		2797
		2798	Calls that try to "import" foreign memory areas (such as C<IO::AIO::mmap>
		2799	or C<IO::AIO::aio_slurp>) do not work with generic lvalues, such as
		2800	non-created hash slots or other scalars I didn't think of. It's best to
		2801	avoid such and either use scalar variables or making sure that the scalar
		2802	exists (e.g. by storing C<undef>) and isn't "funny" (e.g. tied).
		2803
		2804	I am not sure anything can be done about this, so this is considered a
		2805	known issue, rather than a bug.
2334		2806
2335	=head1 SEE ALSO	2807	=head1 SEE ALSO
2336		2808
2337	L<AnyEvent::AIO> for easy integration into event loops, L<Coro::AIO> for a	2809	L<AnyEvent::AIO> for easy integration into event loops, L<Coro::AIO> for a
2338	more natural syntax.	2810	more natural syntax and L<IO::FDPass> for file descriptor passing.
2339		2811
2340	=head1 AUTHOR	2812	=head1 AUTHOR
2341		2813
2342	Marc Lehmann <schmorp@schmorp.de>	2814	Marc Lehmann <schmorp@schmorp.de>
2343	http://home.schmorp.de/	2815	http://home.schmorp.de/

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Comparing IO-AIO/AIO.pm (file contents): Revision 1.281 by root, Tue Feb 20 04:32:59 2018 UTC vs. Revision 1.318 by root, Sat Apr 1 02:14:05 2023 UTC

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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.281 by root, Tue Feb 20 04:32:59 2018 UTC vs.
Revision 1.318 by root, Sat Apr 1 02:14:05 2023 UTC