[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 1.300 by root, Sun Mar 10 12:11:46 2019 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 = 4.71;
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		198
199	push @AIO_REQ, qw(aio_busy); # not exported	199	push @AIO_REQ, qw(aio_busy); # not exported
200		200
201	@IO::AIO::GRP::ISA = 'IO::AIO::REQ';	201	@IO::AIO::GRP::ISA = 'IO::AIO::REQ';
202		202
…		…
285		285
286	IO::AIO::sendfile $ofh, $ifh, $offset, $count	286	IO::AIO::sendfile $ofh, $ifh, $offset, $count
287	IO::AIO::fadvise $fh, $offset, $len, $advice	287	IO::AIO::fadvise $fh, $offset, $len, $advice
288	IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]]	288	IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]]
289	IO::AIO::munmap $scalar	289	IO::AIO::munmap $scalar
		290	IO::AIO::mremap $scalar, $new_length, $flags[, $new_address]
290	IO::AIO::madvise $scalar, $offset, $length, $advice	291	IO::AIO::madvise $scalar, $offset, $length, $advice
291	IO::AIO::mprotect $scalar, $offset, $length, $protect	292	IO::AIO::mprotect $scalar, $offset, $length, $protect
292	IO::AIO::munlock $scalar, $offset = 0, $length = undef	293	IO::AIO::munlock $scalar, $offset = 0, $length = undef
293	IO::AIO::munlockall	294	IO::AIO::munlockall
294		295
…		…
404	following POSIX and non-POSIX constants are available (missing ones on	405	following POSIX and non-POSIX constants are available (missing ones on
405	your system are, as usual, C<0>):	406	your system are, as usual, C<0>):
406		407
407	C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,	408	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>,	409	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>.	410	C<O_RSYNC>, C<O_SYNC>, C<O_PATH>, C<O_TMPFILE>, C<O_TTY_INIT> and C<O_ACCMODE>.
410		411
411		412
412	=item aio_close $fh, $callback->($status)	413	=item aio_close $fh, $callback->($status)
413		414
414	Asynchronously close a file and call the callback with the result	415	Asynchronously close a file and call the callback with the result
…		…
540		541
541	=item aio_stat $fh_or_path, $callback->($status)	542	=item aio_stat $fh_or_path, $callback->($status)
542		543
543	=item aio_lstat $fh, $callback->($status)	544	=item aio_lstat $fh, $callback->($status)
544		545
545	Works like perl's C<stat> or C<lstat> in void context. The callback will	546	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 _>	547	callback will be called after the stat and the results will be available
547	or C<-s _> etc...	548	using C<stat _> or C<-s _> and other tests (with the exception of C<-B>
		549	and C<-T>).
548		550
549	The pathname passed to C<aio_stat> must be absolute. See API NOTES, above,	551	The pathname passed to C<aio_stat> must be absolute. See API NOTES, above,
550	for an explanation.	552	for an explanation.
551		553
552	Currently, the stats are always 64-bit-stats, i.e. instead of returning an	554	Currently, the stats are always 64-bit-stats, i.e. instead of returning an
…		…
559	behaviour).	561	behaviour).
560		562
561	C<S_IFMT>, C<S_IFIFO>, C<S_IFCHR>, C<S_IFBLK>, C<S_IFLNK>, C<S_IFREG>,	563	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>,	564	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>.	565	C<IO::AIO::minor $dev_t>, C<IO::AIO::makedev $major, $minor>.
		566
		567	To access higher resolution stat timestamps, see L<SUBSECOND STAT TIME
		568	ACCESS>.
564		569
565	Example: Print the length of F</etc/passwd>:	570	Example: Print the length of F</etc/passwd>:
566		571
567	aio_stat "/etc/passwd", sub {	572	aio_stat "/etc/passwd", sub {
568	$_[0] and die "stat failed: $!";	573	$_[0] and die "stat failed: $!";
…		…
618		623
619	Works like perl's C<utime> function (including the special case of $atime	624	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	625	and $mtime being undef). Fractional times are supported if the underlying
621	syscalls support them.	626	syscalls support them.
622		627
623	When called with a pathname, uses utimes(2) if available, otherwise	628	When called with a pathname, uses utimensat(2) or utimes(2) if available,
624	utime(2). If called on a file descriptor, uses futimes(2) if available,	629	otherwise utime(2). If called on a file descriptor, uses futimens(2)
625	otherwise returns ENOSYS, so this is not portable.	630	or futimes(2) if available, otherwise returns ENOSYS, so this is not
		631	portable.
626		632
627	Examples:	633	Examples:
628		634
629	# set atime and mtime to current time (basically touch(1)):	635	# set atime and mtime to current time (basically touch(1)):
630	aio_utime "path", undef, undef;	636	aio_utime "path", undef, undef;
…		…
789		795
790	=over 4	796	=over 4
791		797
792	=item IO::AIO::READDIR_DENTS	798	=item IO::AIO::READDIR_DENTS
793		799
794	When this flag is off, then the callback gets an arrayref consisting of	800	Normally the callback gets an arrayref consisting of names only (as
795	names only (as with C<aio_readdir>), otherwise it gets an arrayref with	801	with C<aio_readdir>). If this flag is set, then the callback gets an
796	C<[$name, $type, $inode]> arrayrefs, each describing a single directory	802	arrayref with C<[$name, $type, $inode]> arrayrefs, each describing a
797	entry in more detail.	803	single directory entry in more detail:
798		804
799	C<$name> is the name of the entry.	805	C<$name> is the name of the entry.
800		806
801	C<$type> is one of the C<IO::AIO::DT_xxx> constants:	807	C<$type> is one of the C<IO::AIO::DT_xxx> constants:
802		808
803	C<IO::AIO::DT_UNKNOWN>, C<IO::AIO::DT_FIFO>, C<IO::AIO::DT_CHR>, C<IO::AIO::DT_DIR>,	809	C<IO::AIO::DT_UNKNOWN>, C<IO::AIO::DT_FIFO>, C<IO::AIO::DT_CHR>, C<IO::AIO::DT_DIR>,
804	C<IO::AIO::DT_BLK>, C<IO::AIO::DT_REG>, C<IO::AIO::DT_LNK>, C<IO::AIO::DT_SOCK>,	810	C<IO::AIO::DT_BLK>, C<IO::AIO::DT_REG>, C<IO::AIO::DT_LNK>, C<IO::AIO::DT_SOCK>,
805	C<IO::AIO::DT_WHT>.	811	C<IO::AIO::DT_WHT>.
806		812
807	C<IO::AIO::DT_UNKNOWN> means just that: readdir does not know. If you need to	813	C<IO::AIO::DT_UNKNOWN> means just that: readdir does not know. If you need
808	know, you have to run stat yourself. Also, for speed reasons, the C<$type>	814	to know, you have to run stat yourself. Also, for speed/memory reasons,
809	scalars are read-only: you can not modify them.	815	the C<$type> scalars are read-only: you must not modify them.
810		816
811	C<$inode> is the inode number (which might not be exact on systems with 64	817	C<$inode> is the inode number (which might not be exact on systems with 64
812	bit inode numbers and 32 bit perls). This field has unspecified content on	818	bit inode numbers and 32 bit perls). This field has unspecified content on
813	systems that do not deliver the inode information.	819	systems that do not deliver the inode information.
814		820
…		…
825	short names are tried first.	831	short names are tried first.
826		832
827	=item IO::AIO::READDIR_STAT_ORDER	833	=item IO::AIO::READDIR_STAT_ORDER
828		834
829	When this flag is set, then the names will be returned in an order	835	When this flag is set, then the names will be returned in an order
830	suitable for stat()'ing each one. That is, when you plan to stat()	836	suitable for stat()'ing each one. That is, when you plan to stat() most or
831	all files in the given directory, then the returned order will likely	837	all files in the given directory, then the returned order will likely be
832	be fastest.	838	faster.
833		839
834	If both this flag and C<IO::AIO::READDIR_DIRS_FIRST> are specified, then	840	If both this flag and C<IO::AIO::READDIR_DIRS_FIRST> are specified,
835	the likely dirs come first, resulting in a less optimal stat order.	841	then the likely dirs come first, resulting in a less optimal stat order
		842	for stat'ing all entries, but likely a more optimal order for finding
		843	subdirectories.
836		844
837	=item IO::AIO::READDIR_FOUND_UNKNOWN	845	=item IO::AIO::READDIR_FOUND_UNKNOWN
838		846
839	This flag should not be set when calling C<aio_readdirx>. Instead, it	847	This flag should not be set when calling C<aio_readdirx>. Instead, it
840	is being set by C<aio_readdirx>, when any of the C<$type>'s found were	848	is being set by C<aio_readdirx>, when any of the C<$type>'s found were
…		…
1101	aioreq_pri $pri;	1109	aioreq_pri $pri;
1102	add $grp aio_stat $wd, sub {	1110	add $grp aio_stat $wd, sub {
1103	return $grp->result () if $_[0];	1111	return $grp->result () if $_[0];
1104	my $now = time;	1112	my $now = time;
1105	my $hash1 = join ":", (stat _)[0,1,3,7,9];	1113	my $hash1 = join ":", (stat _)[0,1,3,7,9];
		1114	my $rdxflags = READDIR_DIRS_FIRST;
		1115
		1116	if ((stat _)[3] < 2) {
		1117	# at least one non-POSIX filesystem exists
		1118	# that returns useful DT_type values: btrfs,
		1119	# so optimise for this here by requesting dents
		1120	$rdxflags \|= READDIR_DENTS;
		1121	}
1106		1122
1107	# read the directory entries	1123	# read the directory entries
1108	aioreq_pri $pri;	1124	aioreq_pri $pri;
1109	add $grp aio_readdirx $wd, READDIR_DIRS_FIRST, sub {	1125	add $grp aio_readdirx $wd, $rdxflags, sub {
1110	my $entries = shift	1126	my ($entries, $flags) = @_
1111	or return $grp->result ();	1127	or return $grp->result ();
		1128
		1129	if ($rdxflags & READDIR_DENTS) {
		1130	# if we requested type values, see if we can use them directly.
		1131
		1132	# if there were any DT_UNKNOWN entries then we assume we
		1133	# don't know. alternatively, we could assume that if we get
		1134	# one DT_DIR, then all directories are indeed marked with
		1135	# DT_DIR, but this seems not required for btrfs, and this
		1136	# is basically the "btrfs can't get it's act together" code
		1137	# branch.
		1138	unless ($flags & READDIR_FOUND_UNKNOWN) {
		1139	# now we have valid DT_ information for all entries,
		1140	# so use it as an optimisation without further stat's.
		1141	# they must also all be at the beginning of @$entries
		1142	# by now.
		1143
		1144	my $dirs;
		1145
		1146	if (@$entries) {
		1147	for (0 .. $#$entries) {
		1148	if ($entries->[$_][1] != DT_DIR) {
		1149	# splice out directories
		1150	$dirs = [splice @$entries, 0, $_];
		1151	last;
		1152	}
		1153	}
		1154
		1155	# if we didn't find any non-dir, then all entries are dirs
		1156	unless ($dirs) {
		1157	($dirs, $entries) = ($entries, []);
		1158	}
		1159	} else {
		1160	# directory is empty, so there are no sbdirs
		1161	$dirs = [];
		1162	}
		1163
		1164	# either splice'd the directories out or the dir was empty.
		1165	# convert dents to filenames
		1166	$_ = $_->[0] for @$dirs;
		1167	$_ = $_->[0] for @$entries;
		1168
		1169	return $grp->result ($dirs, $entries);
		1170	}
		1171
		1172	# cannot use, so return to our old ways
		1173	# by pretending we only scanned for names.
		1174	$_ = $_->[0] for @$entries;
		1175	}
1112		1176
1113	# stat the dir another time	1177	# stat the dir another time
1114	aioreq_pri $pri;	1178	aioreq_pri $pri;
1115	add $grp aio_stat $wd, sub {	1179	add $grp aio_stat $wd, sub {
1116	my $hash2 = join ":", (stat _)[0,1,3,7,9];	1180	my $hash2 = join ":", (stat _)[0,1,3,7,9];
…		…
1377	IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh;	1441	IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh;
1378	aio_mlock $data; # mlock in background	1442	aio_mlock $data; # mlock in background
1379		1443
1380	=item aio_mlockall $flags, $callback->($status)	1444	=item aio_mlockall $flags, $callback->($status)
1381		1445
1382	Calls the C<mlockall> function with the given C<$flags> (a combination of	1446	Calls the C<mlockall> function with the given C<$flags> (a
1383	C<IO::AIO::MCL_CURRENT> and C<IO::AIO::MCL_FUTURE>).	1447	combination of C<IO::AIO::MCL_CURRENT>, C<IO::AIO::MCL_FUTURE> and
		1448	C<IO::AIO::MCL_ONFAULT>).
1384		1449
1385	On systems that do not implement C<mlockall>, this function returns C<-1>	1450	On systems that do not implement C<mlockall>, this function returns C<-1>
1386	and sets errno to C<ENOSYS>.	1451	and sets errno to C<ENOSYS>. Similarly, flag combinations not supported
		1452	by the system result in a return value of C<-1> with errno being set to
		1453	C<EINVAL>.
1387		1454
1388	Note that the corresponding C<munlockall> is synchronous and is	1455	Note that the corresponding C<munlockall> is synchronous and is
1389	documented under L<MISCELLANEOUS FUNCTIONS>.	1456	documented under L<MISCELLANEOUS FUNCTIONS>.
1390		1457
1391	Example: asynchronously lock all current and future pages into memory.	1458	Example: asynchronously lock all current and future pages into memory.
…		…
1776	The default value for the limit is C<0>, but note that setting a feeder	1843	The default value for the limit is C<0>, but note that setting a feeder
1777	automatically bumps it up to C<2>.	1844	automatically bumps it up to C<2>.
1778		1845
1779	=back	1846	=back
1780		1847
		1848
1781	=head2 SUPPORT FUNCTIONS	1849	=head2 SUPPORT FUNCTIONS
1782		1850
1783	=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION	1851	=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION
1784		1852
1785	=over 4	1853	=over 4
…		…
1850	Strictly equivalent to:	1918	Strictly equivalent to:
1851		1919
1852	IO::AIO::poll_wait, IO::AIO::poll_cb	1920	IO::AIO::poll_wait, IO::AIO::poll_cb
1853	while IO::AIO::nreqs;	1921	while IO::AIO::nreqs;
1854		1922
		1923	This function can be useful at program aborts, to make sure outstanding
		1924	I/O has been done (C<IO::AIO> uses an C<END> block which already calls
		1925	this function on normal exits), or when you are merely using C<IO::AIO>
		1926	for its more advanced functions, rather than for async I/O, e.g.:
		1927
		1928	my ($dirs, $nondirs);
		1929	IO::AIO::aio_scandir "/tmp", 0, sub { ($dirs, $nondirs) = @_ };
		1930	IO::AIO::flush;
		1931	# $dirs, $nondirs are now set
		1932
1855	=item IO::AIO::max_poll_reqs $nreqs	1933	=item IO::AIO::max_poll_reqs $nreqs
1856		1934
1857	=item IO::AIO::max_poll_time $seconds	1935	=item IO::AIO::max_poll_time $seconds
1858		1936
1859	These set the maximum number of requests (default C<0>, meaning infinity)	1937	These set the maximum number of requests (default C<0>, meaning infinity)
…		…
1885	poll => 'r', nice => 1,	1963	poll => 'r', nice => 1,
1886	cb => &IO::AIO::poll_cb);	1964	cb => &IO::AIO::poll_cb);
1887		1965
1888	=back	1966	=back
1889		1967
		1968
1890	=head3 CONTROLLING THE NUMBER OF THREADS	1969	=head3 CONTROLLING THE NUMBER OF THREADS
1891		1970
1892	=over	1971	=over
1893		1972
1894	=item IO::AIO::min_parallel $nthreads	1973	=item IO::AIO::min_parallel $nthreads
…		…
1981	The default value for C<max_outstanding> is very large, so there is no	2060	The default value for C<max_outstanding> is very large, so there is no
1982	practical limit on the number of outstanding requests.	2061	practical limit on the number of outstanding requests.
1983		2062
1984	=back	2063	=back
1985		2064
		2065
1986	=head3 STATISTICAL INFORMATION	2066	=head3 STATISTICAL INFORMATION
1987		2067
1988	=over	2068	=over
1989		2069
1990	=item IO::AIO::nreqs	2070	=item IO::AIO::nreqs
…		…
2006		2086
2007	Returns the number of requests currently in the pending state (executed,	2087	Returns the number of requests currently in the pending state (executed,
2008	but not yet processed by poll_cb).	2088	but not yet processed by poll_cb).
2009		2089
2010	=back	2090	=back
		2091
		2092
		2093	=head3 SUBSECOND STAT TIME ACCESS
		2094
		2095	Both C<aio_stat>/C<aio_lstat> and perl's C<stat>/C<lstat> functions can
		2096	generally find access/modification and change times with subsecond time
		2097	accuracy of the system supports it, but perl's built-in functions only
		2098	return the integer part.
		2099
		2100	The following functions return the timestamps of the most recent
		2101	stat with subsecond precision on most systems and work both after
		2102	C<aio_stat>/C<aio_lstat> and perl's C<stat>/C<lstat> calls. Their return
		2103	value is only meaningful after a successful C<stat>/C<lstat> call, or
		2104	during/after a successful C<aio_stat>/C<aio_lstat> callback.
		2105
		2106	This is similar to the L<Time::HiRes> C<stat> functions, but can return
		2107	full resolution without rounding and work with standard perl C<stat>,
		2108	alleviating the need to call the special C<Time::HiRes> functions, which
		2109	do not act like their perl counterparts.
		2110
		2111	On operating systems or file systems where subsecond time resolution is
		2112	not supported or could not be detected, a fractional part of C<0> is
		2113	returned, so it is always safe to call these functions.
		2114
		2115	=over 4
		2116
		2117	=item $seconds = IO::AIO::st_atime, IO::AIO::st_mtime, IO::AIO::st_ctime, IO::AIO::st_btime
		2118
		2119	Return the access, modication, change or birth time, respectively,
		2120	including fractional part. Due to the limited precision of floating point,
		2121	the accuracy on most platforms is only a bit better than milliseconds
		2122	for times around now - see the I<nsec> function family, below, for full
		2123	accuracy.
		2124
		2125	File birth time is only available when the OS and perl support it (on
		2126	FreeBSD and NetBSD at the time of this writing, although support is
		2127	adaptive, so if your OS/perl gains support, IO::AIO can take avdantage of
		2128	it). On systems where it isn't available, C<0> is currently returned, but
		2129	this might change to C<undef> in a future version.
		2130
		2131	=item ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtime
		2132
		2133	Returns access, modification, change and birth time all in one go, and
		2134	maybe more times in the future version.
		2135
		2136	=item $nanoseconds = IO::AIO::st_atimensec, IO::AIO::st_mtimensec, IO::AIO::st_ctimensec, IO::AIO::st_btimensec
		2137
		2138	Return the fractional access, modifcation, change or birth time, in nanoseconds,
		2139	as an integer in the range C<0> to C<999999999>.
		2140
		2141	Note that no accessors are provided for access, modification and
		2142	change times - you need to get those from C<stat _> if required (C<int
		2143	IO::AIO::st_atime> and so on will I<not> generally give you the correct
		2144	value).
		2145
		2146	=item $seconds = IO::AIO::st_btimesec
		2147
		2148	The (integral) seconds part of the file birth time, if available.
		2149
		2150	=item ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtimensec
		2151
		2152	Like the functions above, but returns all four times in one go (and maybe
		2153	more in future versions).
		2154
		2155	=item $counter = IO::AIO::st_gen
		2156
		2157	Returns the generation counter (in practice this is just a random number)
		2158	of the file. This is only available on platforms which have this member in
		2159	their C<struct stat> (most BSDs at the time of this writing) and generally
		2160	only to the root usert. If unsupported, C<0> is returned, but this might
		2161	change to C<undef> in a future version.
		2162
		2163	=back
		2164
		2165	Example: print the high resolution modification time of F</etc>, using
		2166	C<stat>, and C<IO::AIO::aio_stat>.
		2167
		2168	if (stat "/etc") {
		2169	printf "stat(/etc) mtime: %f\n", IO::AIO::st_mtime;
		2170	}
		2171
		2172	IO::AIO::aio_stat "/etc", sub {
		2173	$_[0]
		2174	and return;
		2175
		2176	printf "aio_stat(/etc) mtime: %d.%09d\n", (stat _)[9], IO::AIO::st_mtimensec;
		2177	};
		2178
		2179	IO::AIO::flush;
		2180
		2181	Output of the awbove on my system, showing reduced and full accuracy:
		2182
		2183	stat(/etc) mtime: 1534043702.020808
		2184	aio_stat(/etc) mtime: 1534043702.020807792
		2185
2011		2186
2012	=head3 MISCELLANEOUS FUNCTIONS	2187	=head3 MISCELLANEOUS FUNCTIONS
2013		2188
2014	IO::AIO implements some functions that are useful when you want to use	2189	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	2190	some "Advanced I/O" function not available to in Perl, without going the
…		…
2156		2331
2157	=item IO::AIO::munmap $scalar	2332	=item IO::AIO::munmap $scalar
2158		2333
2159	Removes a previous mmap and undefines the C<$scalar>.	2334	Removes a previous mmap and undefines the C<$scalar>.
2160		2335
		2336	=item IO::AIO::mremap $scalar, $new_length, $flags = MREMAP_MAYMOVE[, $new_address = 0]
		2337
		2338	Calls the Linux-specific mremap(2) system call. The C<$scalar> must have
		2339	been mapped by C<IO::AIO::mmap>, and C<$flags> must currently either be
		2340	C<0> or C<IO::AIO::MREMAP_MAYMOVE>.
		2341
		2342	Returns true if successful, and false otherwise. If the underlying mmapped
		2343	region has changed address, then the true value has the numerical value
		2344	C<1>, otherwise it has the numerical value C<0>:
		2345
		2346	my $success = IO::AIO::mremap $mmapped, 8192, IO::AIO::MREMAP_MAYMOVE
		2347	or die "mremap: $!";
		2348
		2349	if ($success*1) {
		2350	warn "scalar has chanegd address in memory\n";
		2351	}
		2352
		2353	C<IO::AIO::MREMAP_FIXED> and the C<$new_address> argument are currently
		2354	implemented, but not supported and might go away in a future version.
		2355
		2356	On systems where this call is not supported or is not emulated, this call
		2357	returns falls and sets C<$!> to C<ENOSYS>.
		2358
		2359	=item IO::AIO::mlockall $flags
		2360
		2361	Calls the C<eio_mlockall_sync> function, which is like C<aio_mlockall>,
		2362	but is blocking.
		2363
2161	=item IO::AIO::munlock $scalar, $offset = 0, $length = undef	2364	=item IO::AIO::munlock $scalar, $offset = 0, $length = undef
2162		2365
2163	Calls the C<munlock> function, undoing the effects of a previous	2366	Calls the C<munlock> function, undoing the effects of a previous
2164	C<aio_mlock> call (see its description for details).	2367	C<aio_mlock> call (see its description for details).
2165		2368
…		…
2220	Example: create a pipe race-free w.r.t. threads and fork:	2423	Example: create a pipe race-free w.r.t. threads and fork:
2221		2424
2222	my ($rfh, $wfh) = IO::AIO::pipe2 IO::AIO::O_CLOEXEC	2425	my ($rfh, $wfh) = IO::AIO::pipe2 IO::AIO::O_CLOEXEC
2223	or die "pipe2: $!\n";	2426	or die "pipe2: $!\n";
2224		2427
2225	=item $fh = IO::AIO::eventfd ([$initval, [$flags]])	2428	=item $fh = IO::AIO::eventfd [$initval, [$flags]]
2226		2429
2227	This is a direct interface to the Linux L<eventfd(2)> system call. The	2430	This is a direct interface to the Linux L<eventfd(2)> system call. The
2228	(unhelpful) defaults for C<$initval> and C<$flags> are C<0> for both.	2431	(unhelpful) defaults for C<$initval> and C<$flags> are C<0> for both.
2229		2432
2230	On success, the new eventfd filehandle is returned, otherwise returns	2433	On success, the new eventfd filehandle is returned, otherwise returns
…		…
2232		2435
2233	Please refer to L<eventfd(2)> for more info on this call.	2436	Please refer to L<eventfd(2)> for more info on this call.
2234		2437
2235	The following symbol flag values are available: C<IO::AIO::EFD_CLOEXEC>,	2438	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).	2439	C<IO::AIO::EFD_NONBLOCK> and C<IO::AIO::EFD_SEMAPHORE> (Linux 2.6.30).
		2440
		2441	Example: create a new eventfd filehandle:
		2442
		2443	$fh = IO::AIO::eventfd 0, IO::AIO::O_CLOEXEC
		2444	or die "eventfd: $!\n";
		2445
		2446	=item $fh = IO::AIO::timerfd_create $clockid[, $flags]
		2447
		2448	This is a direct interface to the Linux L<timerfd_create(2)> system call. The
		2449	(unhelpful) default for C<$flags> is C<0>.
		2450
		2451	On success, the new timerfd filehandle is returned, otherwise returns
		2452	C<undef>. If the eventfd syscall is missing, fails with C<ENOSYS>.
		2453
		2454	Please refer to L<timerfd_create(2)> for more info on this call.
		2455
		2456	The following C<$clockid> values are
		2457	available: C<IO::AIO::CLOCK_REALTIME>, C<IO::AIO::CLOCK_MONOTONIC>
		2458	C<IO::AIO::CLOCK_CLOCK_BOOTTIME> (Linux 3.15)
		2459	C<IO::AIO::CLOCK_CLOCK_REALTIME_ALARM> (Linux 3.11) and
		2460	C<IO::AIO::CLOCK_CLOCK_BOOTTIME_ALARM> (Linux 3.11).
		2461
		2462	The following C<$flags> values are available (Linux
		2463	2.6.27): C<IO::AIO::TFD_NONBLOCK> and C<IO::AIO::TFD_CLOEXEC>.
		2464
		2465	Example: create a new timerfd and set it to one-second repeated alarms,
		2466	then wait for two alarms:
		2467
		2468	my $fh = IO::AIO::timerfd_create IO::AIO::CLOCK_BOOTTIME, IO::AIO::TFD_CLOEXEC
		2469	or die "timerfd_create: $!\n";
		2470
		2471	defined IO::AIO::timerfd_settime $fh, 0, 1, 1
		2472	or die "timerfd_settime: $!\n";
		2473
		2474	for (1..2) {
		2475	8 == sysread $fh, my $buf, 8
		2476	or die "timerfd read failure\n";
		2477
		2478	printf "number of expirations (likely 1): %d\n",
		2479	unpack "Q", $buf;
		2480	}
		2481
		2482	=item ($cur_interval, $cur_value) = IO::AIO::timerfd_settime $fh, $flags, $new_interval, $nbw_value
		2483
		2484	This is a direct interface to the Linux L<timerfd_settime(2)> system
		2485	call. Please refer to its manpage for more info on this call.
		2486
		2487	The new itimerspec is specified using two (possibly fractional) second
		2488	values, C<$new_interval> and C<$new_value>).
		2489
		2490	On success, the current interval and value are returned (as per
		2491	C<timerfd_gettime>). On failure, the empty list is returned.
		2492
		2493	The following C<$flags> values are
		2494	available: C<IO::AIO::TFD_TIMER_ABSTIME> and
		2495	C<IO::AIO::TFD_TIMER_CANCEL_ON_SET>.
		2496
		2497	See C<IO::AIO::timerfd_create> for a full example.
		2498
		2499	=item ($cur_interval, $cur_value) = IO::AIO::timerfd_gettime $fh
		2500
		2501	This is a direct interface to the Linux L<timerfd_gettime(2)> system
		2502	call. Please refer to its manpage for more info on this call.
		2503
		2504	On success, returns the current values of interval and value for the given
		2505	timerfd (as potentially fractional second values). On failure, the empty
		2506	list is returned.
2237		2507
2238	=back	2508	=back
2239		2509
2240	=cut	2510	=cut
2241		2511
…		…
2307	the process will result in undefined behaviour. Calling it at any time	2577	the process will result in undefined behaviour. Calling it at any time
2308	will also result in any undefined (by POSIX) behaviour.	2578	will also result in any undefined (by POSIX) behaviour.
2309		2579
2310	=back	2580	=back
2311		2581
		2582	=head2 LINUX-SPECIFIC CALLS
		2583
		2584	When a call is documented as "linux-specific" then this means it
		2585	originated on GNU/Linux. C<IO::AIO> will usually try to autodetect the
		2586	availability and compatibility of such calls regardless of the platform
		2587	it is compiled on, so platforms such as FreeBSD which often implement
		2588	these calls will work. When in doubt, call them and see if they fail wth
		2589	C<ENOSYS>.
		2590
2312	=head2 MEMORY USAGE	2591	=head2 MEMORY USAGE
2313		2592
2314	Per-request usage:	2593	Per-request usage:
2315		2594
2316	Each aio request uses - depending on your architecture - around 100-200	2595	Each aio request uses - depending on your architecture - around 100-200
…		…
2328	temporary buffers, and each thread requires a stack and other data	2607	temporary buffers, and each thread requires a stack and other data
2329	structures (usually around 16k-128k, depending on the OS).	2608	structures (usually around 16k-128k, depending on the OS).
2330		2609
2331	=head1 KNOWN BUGS	2610	=head1 KNOWN BUGS
2332		2611
2333	Known bugs will be fixed in the next release.	2612	Known bugs will be fixed in the next release :)
		2613
		2614	=head1 KNOWN ISSUES
		2615
		2616	Calls that try to "import" foreign memory areas (such as C<IO::AIO::mmap>
		2617	or C<IO::AIO::aio_slurp>) do not work with generic lvalues, such as
		2618	non-created hash slots or other scalars I didn't think of. It's best to
		2619	avoid such and either use scalar variables or making sure that the scalar
		2620	exists (e.g. by storing C<undef>) and isn't "funny" (e.g. tied).
		2621
		2622	I am not sure anything can be done about this, so this is considered a
		2623	known issue, rather than a bug.
2334		2624
2335	=head1 SEE ALSO	2625	=head1 SEE ALSO
2336		2626
2337	L<AnyEvent::AIO> for easy integration into event loops, L<Coro::AIO> for a	2627	L<AnyEvent::AIO> for easy integration into event loops, L<Coro::AIO> for a
2338	more natural syntax.	2628	more natural syntax.

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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 1.300 by root, Sun Mar 10 12:11:46 2019 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 1.300 by root, Sun Mar 10 12:11:46 2019 UTC