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

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.237 by root, Thu Oct 11 03:20:52 2012 UTC vs.
Revision 1.262 by root, Thu Jun 9 03:15:37 2016 UTC

…		…
68	=head2 EXAMPLE	68	=head2 EXAMPLE
69		69
70	This is a simple example that uses the EV module and loads	70	This is a simple example that uses the EV module and loads
71	F</etc/passwd> asynchronously:	71	F</etc/passwd> asynchronously:
72		72
73	use Fcntl;
74	use EV;	73	use EV;
75	use IO::AIO;	74	use IO::AIO;
76		75
77	# register the IO::AIO callback with EV	76	# register the IO::AIO callback with EV
78	my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;	77	my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
…		…
95		94
96	# file contents now in $contents	95	# file contents now in $contents
97	print $contents;	96	print $contents;
98		97
99	# exit event loop and program	98	# exit event loop and program
100	EV::unloop;	99	EV::break;
101	};	100	};
102	};	101	};
103		102
104	# possibly queue up other requests, or open GUI windows,	103	# possibly queue up other requests, or open GUI windows,
105	# check for sockets etc. etc.	104	# check for sockets etc. etc.
106		105
107	# process events as long as there are some:	106	# process events as long as there are some:
108	EV::loop;	107	EV::run;
109		108
110	=head1 REQUEST ANATOMY AND LIFETIME	109	=head1 REQUEST ANATOMY AND LIFETIME
111		110
112	Every C<aio_*> function creates a request. which is a C data structure not	111	Every C<aio_*> function creates a request. which is a C data structure not
113	directly visible to Perl.	112	directly visible to Perl.
…		…
168	use common::sense;	167	use common::sense;
169		168
170	use base 'Exporter';	169	use base 'Exporter';
171		170
172	BEGIN {	171	BEGIN {
173	our $VERSION = '4.17';	172	our $VERSION = 4.34;
174		173
175	our @AIO_REQ = qw(aio_sendfile aio_seek aio_read aio_write aio_open aio_close	174	our @AIO_REQ = qw(aio_sendfile aio_seek aio_read aio_write aio_open aio_close
176	aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx	175	aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx
177	aio_scandir aio_symlink aio_readlink aio_realpath aio_sync	176	aio_scandir aio_symlink aio_readlink aio_realpath aio_fcntl aio_ioctl
178	aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range aio_allocate	177	aio_sync aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range
179	aio_pathsync aio_readahead aio_fiemap	178	aio_pathsync aio_readahead aio_fiemap aio_allocate
180	aio_rename aio_link aio_move aio_copy aio_group	179	aio_rename aio_link aio_move aio_copy aio_group
181	aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown	180	aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown
182	aio_chmod aio_utime aio_truncate	181	aio_chmod aio_utime aio_truncate
183	aio_msync aio_mtouch aio_mlock aio_mlockall	182	aio_msync aio_mtouch aio_mlock aio_mlockall
184	aio_statvfs	183	aio_statvfs
…		…
228	aio_unlink $pathname, $callback->($status)	227	aio_unlink $pathname, $callback->($status)
229	aio_mknod $pathname, $mode, $dev, $callback->($status)	228	aio_mknod $pathname, $mode, $dev, $callback->($status)
230	aio_link $srcpath, $dstpath, $callback->($status)	229	aio_link $srcpath, $dstpath, $callback->($status)
231	aio_symlink $srcpath, $dstpath, $callback->($status)	230	aio_symlink $srcpath, $dstpath, $callback->($status)
232	aio_readlink $pathname, $callback->($link)	231	aio_readlink $pathname, $callback->($link)
233	aio_realpath $pathname, $callback->($link)	232	aio_realpath $pathname, $callback->($path)
234	aio_rename $srcpath, $dstpath, $callback->($status)	233	aio_rename $srcpath, $dstpath, $callback->($status)
235	aio_mkdir $pathname, $mode, $callback->($status)	234	aio_mkdir $pathname, $mode, $callback->($status)
236	aio_rmdir $pathname, $callback->($status)	235	aio_rmdir $pathname, $callback->($status)
237	aio_readdir $pathname, $callback->($entries)	236	aio_readdir $pathname, $callback->($entries)
238	aio_readdirx $pathname, $flags, $callback->($entries, $flags)	237	aio_readdirx $pathname, $flags, $callback->($entries, $flags)
…		…
241	aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)	240	aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
242	aio_load $pathname, $data, $callback->($status)	241	aio_load $pathname, $data, $callback->($status)
243	aio_copy $srcpath, $dstpath, $callback->($status)	242	aio_copy $srcpath, $dstpath, $callback->($status)
244	aio_move $srcpath, $dstpath, $callback->($status)	243	aio_move $srcpath, $dstpath, $callback->($status)
245	aio_rmtree $pathname, $callback->($status)	244	aio_rmtree $pathname, $callback->($status)
		245	aio_fcntl $fh, $cmd, $arg, $callback->($status)
		246	aio_ioctl $fh, $request, $buf, $callback->($status)
246	aio_sync $callback->($status)	247	aio_sync $callback->($status)
247	aio_syncfs $fh, $callback->($status)	248	aio_syncfs $fh, $callback->($status)
248	aio_fsync $fh, $callback->($status)	249	aio_fsync $fh, $callback->($status)
249	aio_fdatasync $fh, $callback->($status)	250	aio_fdatasync $fh, $callback->($status)
250	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)	251	aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
…		…
395	following POSIX and non-POSIX constants are available (missing ones on	396	following POSIX and non-POSIX constants are available (missing ones on
396	your system are, as usual, C<0>):	397	your system are, as usual, C<0>):
397		398
398	C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,	399	C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,
399	C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>,	400	C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>,
400	C<O_RSYNC>, C<O_SYNC> and C<O_TTY_INIT>.	401	C<O_RSYNC>, C<O_SYNC>, C<O_PATH>, C<O_TMPFILE>, and C<O_TTY_INIT>.
401		402
402		403
403	=item aio_close $fh, $callback->($status)	404	=item aio_close $fh, $callback->($status)
404		405
405	Asynchronously close a file and call the callback with the result	406	Asynchronously close a file and call the callback with the result
…		…
509	As native sendfile syscalls (as practically any non-POSIX interface hacked	510	As native sendfile syscalls (as practically any non-POSIX interface hacked
510	together in a hurry to improve benchmark numbers) tend to be rather buggy	511	together in a hurry to improve benchmark numbers) tend to be rather buggy
511	on many systems, this implementation tries to work around some known bugs	512	on many systems, this implementation tries to work around some known bugs
512	in Linux and FreeBSD kernels (probably others, too), but that might fail,	513	in Linux and FreeBSD kernels (probably others, too), but that might fail,
513	so you really really should check the return value of C<aio_sendfile> -	514	so you really really should check the return value of C<aio_sendfile> -
514	fewre bytes than expected might have been transferred.	515	fewer bytes than expected might have been transferred.
515		516
516		517
517	=item aio_readahead $fh,$offset,$length, $callback->($retval)	518	=item aio_readahead $fh,$offset,$length, $callback->($retval)
518		519
519	C<aio_readahead> populates the page cache with data from a file so that	520	C<aio_readahead> populates the page cache with data from a file so that
…		…
523	whole pages, so that offset is effectively rounded down to a page boundary	524	whole pages, so that offset is effectively rounded down to a page boundary
524	and bytes are read up to the next page boundary greater than or equal to	525	and bytes are read up to the next page boundary greater than or equal to
525	(off-set+length). C<aio_readahead> does not read beyond the end of the	526	(off-set+length). C<aio_readahead> does not read beyond the end of the
526	file. The current file offset of the file is left unchanged.	527	file. The current file offset of the file is left unchanged.
527		528
528	If that syscall doesn't exist (likely if your OS isn't Linux) it will be	529	If that syscall doesn't exist (likely if your kernel isn't Linux) it will
529	emulated by simply reading the data, which would have a similar effect.	530	be emulated by simply reading the data, which would have a similar effect.
530		531
531		532
532	=item aio_stat $fh_or_path, $callback->($status)	533	=item aio_stat $fh_or_path, $callback->($status)
533		534
534	=item aio_lstat $fh, $callback->($status)	535	=item aio_lstat $fh, $callback->($status)
…		…
603	namemax => 255,	604	namemax => 255,
604	frsize => 1024,	605	frsize => 1024,
605	fsid => 1810	606	fsid => 1810
606	}	607	}
607		608
608	Here is a (likely partial) list of fsid values used by Linux - it is safe	609	Here is a (likely partial - send me updates!) list of fsid values used by
609	to hardcode these when the $^O is C<linux>:	610	Linux - it is safe to hardcode these when C<$^O> is C<linux>:
610		611
611	0x0000adf5 adfs	612	0x0000adf5 adfs
612	0x0000adff affs	613	0x0000adff affs
613	0x5346414f afs	614	0x5346414f afs
614	0x09041934 anon-inode filesystem	615	0x09041934 anon-inode filesystem
…		…
627	0x00001373 devfs	628	0x00001373 devfs
628	0x00001cd1 devpts	629	0x00001cd1 devpts
629	0x0000f15f ecryptfs	630	0x0000f15f ecryptfs
630	0x00414a53 efs	631	0x00414a53 efs
631	0x0000137d ext	632	0x0000137d ext
632	0x0000ef53 ext2/ext3	633	0x0000ef53 ext2/ext3/ext4
633	0x0000ef51 ext2	634	0x0000ef51 ext2
		635	0xf2f52010 f2fs
634	0x00004006 fat	636	0x00004006 fat
635	0x65735546 fuseblk	637	0x65735546 fuseblk
636	0x65735543 fusectl	638	0x65735543 fusectl
637	0x0bad1dea futexfs	639	0x0bad1dea futexfs
638	0x01161970 gfs2	640	0x01161970 gfs2
639	0x47504653 gpfs	641	0x47504653 gpfs
640	0x00004244 hfs	642	0x00004244 hfs
641	0xf995e849 hpfs	643	0xf995e849 hpfs
		644	0x00c0ffee hostfs
642	0x958458f6 hugetlbfs	645	0x958458f6 hugetlbfs
643	0x2bad1dea inotifyfs	646	0x2bad1dea inotifyfs
644	0x00009660 isofs	647	0x00009660 isofs
645	0x000072b6 jffs2	648	0x000072b6 jffs2
646	0x3153464a jfs	649	0x3153464a jfs
…		…
661	0x00009fa1 openprom	664	0x00009fa1 openprom
662	0x7461636F ocfs2	665	0x7461636F ocfs2
663	0x00009fa0 proc	666	0x00009fa0 proc
664	0x6165676c pstorefs	667	0x6165676c pstorefs
665	0x0000002f qnx4	668	0x0000002f qnx4
		669	0x68191122 qnx6
666	0x858458f6 ramfs	670	0x858458f6 ramfs
667	0x52654973 reiserfs	671	0x52654973 reiserfs
668	0x00007275 romfs	672	0x00007275 romfs
669	0x67596969 rpc_pipefs	673	0x67596969 rpc_pipefs
670	0x73636673 securityfs	674	0x73636673 securityfs
…		…
723	Works like truncate(2) or ftruncate(2).	727	Works like truncate(2) or ftruncate(2).
724		728
725		729
726	=item aio_allocate $fh, $mode, $offset, $len, $callback->($status)	730	=item aio_allocate $fh, $mode, $offset, $len, $callback->($status)
727		731
728	Allocates or freed disk space according to the C<$mode> argument. See the	732	Allocates or frees disk space according to the C<$mode> argument. See the
729	linux C<fallocate> docuemntation for details.	733	linux C<fallocate> documentation for details.
730		734
731	C<$mode> can currently be C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE>	735	C<$mode> is usually C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> to allocate
732	to allocate space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE \|	736	space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE \| IO::AIO::FALLOC_FL_KEEP_SIZE>,
733	IO::AIO::FALLOC_FL_KEEP_SIZE>, to deallocate a file range.	737	to deallocate a file range.
		738
		739	IO::AIO also supports C<FALLOC_FL_COLLAPSE_RANGE>, to remove a range
		740	(without leaving a hole) and C<FALLOC_FL_ZERO_RANGE>, to zero a range (see
		741	your L<fallocate(2)> manpage).
734		742
735	The file system block size used by C<fallocate> is presumably the	743	The file system block size used by C<fallocate> is presumably the
736	C<f_bsize> returned by C<statvfs>.	744	C<f_bsize> returned by C<statvfs>.
737		745
738	If C<fallocate> isn't available or cannot be emulated (currently no	746	If C<fallocate> isn't available or cannot be emulated (currently no
…		…
783		791
784		792
785	=item aio_realpath $pathname, $callback->($path)	793	=item aio_realpath $pathname, $callback->($path)
786		794
787	Asynchronously make the path absolute and resolve any symlinks in	795	Asynchronously make the path absolute and resolve any symlinks in
788	C<$path>. The resulting path only consists of directories (Same as	796	C<$path>. The resulting path only consists of directories (same as
789	L<Cwd::realpath>).	797	L<Cwd::realpath>).
790		798
791	This request can be used to get the absolute path of the current working	799	This request can be used to get the absolute path of the current working
792	directory by passing it a path of F<.> (a single dot).	800	directory by passing it a path of F<.> (a single dot).
793		801
794		802
795	=item aio_rename $srcpath, $dstpath, $callback->($status)	803	=item aio_rename $srcpath, $dstpath, $callback->($status)
796		804
797	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as	805	Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as
798	rename(2) and call the callback with the result code.	806	rename(2) and call the callback with the result code.
		807
		808	On systems that support the AIO::WD working directory abstraction
		809	natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead
		810	of failing, C<rename> is called on the absolute path of C<$wd>.
799		811
800		812
801	=item aio_mkdir $pathname, $mode, $callback->($status)	813	=item aio_mkdir $pathname, $mode, $callback->($status)
802		814
803	Asynchronously mkdir (create) a directory and call the callback with	815	Asynchronously mkdir (create) a directory and call the callback with
…		…
807		819
808	=item aio_rmdir $pathname, $callback->($status)	820	=item aio_rmdir $pathname, $callback->($status)
809		821
810	Asynchronously rmdir (delete) a directory and call the callback with the	822	Asynchronously rmdir (delete) a directory and call the callback with the
811	result code.	823	result code.
		824
		825	On systems that support the AIO::WD working directory abstraction
		826	natively, the case C<[$wd, "."]> is specialcased - instead of failing,
		827	C<rmdir> is called on the absolute path of C<$wd>.
812		828
813		829
814	=item aio_readdir $pathname, $callback->($entries)	830	=item aio_readdir $pathname, $callback->($entries)
815		831
816	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire	832	Unlike the POSIX call of the same name, C<aio_readdir> reads an entire
…		…
1181	}	1197	}
1182		1198
1183	=item aio_rmtree $pathname, $callback->($status)	1199	=item aio_rmtree $pathname, $callback->($status)
1184		1200
1185	Delete a directory tree starting (and including) C<$path>, return the	1201	Delete a directory tree starting (and including) C<$path>, return the
1186	status of the final C<rmdir> only. This is a composite request that	1202	status of the final C<rmdir> only. This is a composite request that
1187	uses C<aio_scandir> to recurse into and rmdir directories, and unlink	1203	uses C<aio_scandir> to recurse into and rmdir directories, and unlink
1188	everything else.	1204	everything else.
1189		1205
1190	=cut	1206	=cut
1191		1207
…		…
1212	add $grp $dirgrp;	1228	add $grp $dirgrp;
1213	};	1229	};
1214		1230
1215	$grp	1231	$grp
1216	}	1232	}
		1233
		1234	=item aio_fcntl $fh, $cmd, $arg, $callback->($status)
		1235
		1236	=item aio_ioctl $fh, $request, $buf, $callback->($status)
		1237
		1238	These work just like the C<fcntl> and C<ioctl> built-in functions, except
		1239	they execute asynchronously and pass the return value to the callback.
		1240
		1241	Both calls can be used for a lot of things, some of which make more sense
		1242	to run asynchronously in their own thread, while some others make less
		1243	sense. For example, calls that block waiting for external events, such
		1244	as locking, will also lock down an I/O thread while it is waiting, which
		1245	can deadlock the whole I/O system. At the same time, there might be no
		1246	alternative to using a thread to wait.
		1247
		1248	So in general, you should only use these calls for things that do
		1249	(filesystem) I/O, not for things that wait for other events (network,
		1250	other processes), although if you are careful and know what you are doing,
		1251	you still can.
1217		1252
1218	=item aio_sync $callback->($status)	1253	=item aio_sync $callback->($status)
1219		1254
1220	Asynchronously call sync and call the callback when finished.	1255	Asynchronously call sync and call the callback when finished.
1221		1256
…		…
1311		1346
1312	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1347	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
1313	scalars.	1348	scalars.
1314		1349
1315	It touches (reads or writes) all memory pages in the specified	1350	It touches (reads or writes) all memory pages in the specified
1316	range inside the scalar. All caveats and parameters are the same	1351	range inside the scalar. All caveats and parameters are the same
1317	as for C<aio_msync>, above, except for flags, which must be either	1352	as for C<aio_msync>, above, except for flags, which must be either
1318	C<0> (which reads all pages and ensures they are instantiated) or	1353	C<0> (which reads all pages and ensures they are instantiated) or
1319	C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and	1354	C<IO::AIO::MT_MODIFY>, which modifies the memory pages (by reading and
1320	writing an octet from it, which dirties the page).	1355	writing an octet from it, which dirties the page).
1321		1356
1322	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)	1357	=item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
1323		1358
1324	This is a rather advanced IO::AIO call, which works best on mmap(2)ed	1359	This is a rather advanced IO::AIO call, which works best on mmap(2)ed
…		…
1493	aio_stat [$etcdir, "passwd"], sub {	1528	aio_stat [$etcdir, "passwd"], sub {
1494	# yay	1529	# yay
1495	};	1530	};
1496	};	1531	};
1497		1532
1498	That C<aio_wd> is a request and not a normal function shows that creating	1533	The fact that C<aio_wd> is a request and not a normal function shows that
1499	an IO::AIO::WD object is itself a potentially blocking operation, which is	1534	creating an IO::AIO::WD object is itself a potentially blocking operation,
1500	why it is done asynchronously.	1535	which is why it is done asynchronously.
1501		1536
1502	To stat the directory obtained with C<aio_wd> above, one could write	1537	To stat the directory obtained with C<aio_wd> above, one could write
1503	either of the following three request calls:	1538	either of the following three request calls:
1504		1539
1505	aio_lstat "/etc" , sub { ... # pathname as normal string	1540	aio_lstat "/etc" , sub { ... # pathname as normal string
…		…
1525	will still point to the original directory. Most functions accepting a	1560	will still point to the original directory. Most functions accepting a
1526	pathname will use the directory fd on newer systems, and the string on	1561	pathname will use the directory fd on newer systems, and the string on
1527	older systems. Some functions (such as realpath) will always rely on the	1562	older systems. Some functions (such as realpath) will always rely on the
1528	string form of the pathname.	1563	string form of the pathname.
1529		1564
1530	So this fucntionality is mainly useful to get some protection against	1565	So this functionality is mainly useful to get some protection against
1531	C<chdir>, to easily get an absolute path out of a relative path for future	1566	C<chdir>, to easily get an absolute path out of a relative path for future
1532	reference, and to speed up doing many operations in the same directory	1567	reference, and to speed up doing many operations in the same directory
1533	(e.g. when stat'ing all files in a directory).	1568	(e.g. when stat'ing all files in a directory).
1534		1569
1535	The following functions implement this working directory abstraction:	1570	The following functions implement this working directory abstraction:
…		…
1548	passing C<undef> as working directory component of a pathname fails the	1583	passing C<undef> as working directory component of a pathname fails the
1549	request with C<ENOENT>, there is often no need for error checking in the	1584	request with C<ENOENT>, there is often no need for error checking in the
1550	C<aio_wd> callback, as future requests using the value will fail in the	1585	C<aio_wd> callback, as future requests using the value will fail in the
1551	expected way.	1586	expected way.
1552		1587
1553	If this call isn't available because your OS lacks it or it couldn't be
1554	detected, it will be emulated by calling C<fsync> instead.
1555
1556	=item IO::AIO::CWD	1588	=item IO::AIO::CWD
1557		1589
1558	This is a compiletime constant (object) that represents the process	1590	This is a compiletime constant (object) that represents the process
1559	current working directory.	1591	current working directory.
1560		1592
1561	Specifying this object as working directory object for a pathname is as	1593	Specifying this object as working directory object for a pathname is as if
1562	if the pathname would be specified directly, without a directory object,	1594	the pathname would be specified directly, without a directory object. For
1563	e.g., these calls are functionally identical:	1595	example, these calls are functionally identical:
1564		1596
1565	aio_stat "somefile", sub { ... };	1597	aio_stat "somefile", sub { ... };
1566	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };	1598	aio_stat [IO::AIO::CWD, "somefile"], sub { ... };
1567		1599
1568	=back	1600	=back
1569		1601
		1602	To recover the path associated with an IO::AIO::WD object, you can use
		1603	C<aio_realpath>:
		1604
		1605	aio_realpath $wd, sub {
		1606	warn "path is $_[0]\n";
		1607	};
		1608
		1609	Currently, C<aio_statvfs> always, and C<aio_rename> and C<aio_rmdir>
		1610	sometimes, fall back to using an absolue path.
1570		1611
1571	=head2 IO::AIO::REQ CLASS	1612	=head2 IO::AIO::REQ CLASS
1572		1613
1573	All non-aggregate C<aio_*> functions return an object of this class when	1614	All non-aggregate C<aio_*> functions return an object of this class when
1574	called in non-void context.	1615	called in non-void context.
…		…
1752		1793
1753	See C<poll_cb> for an example.	1794	See C<poll_cb> for an example.
1754		1795
1755	=item IO::AIO::poll_cb	1796	=item IO::AIO::poll_cb
1756		1797
1757	Process some outstanding events on the result pipe. You have to call	1798	Process some requests that have reached the result phase (i.e. they have
		1799	been executed but the results are not yet reported). You have to call
		1800	this "regularly" to finish outstanding requests.
		1801
1758	this regularly. Returns C<0> if all events could be processed (or there	1802	Returns C<0> if all events could be processed (or there were no
1759	were no events to process), or C<-1> if it returned earlier for whatever	1803	events to process), or C<-1> if it returned earlier for whatever
1760	reason. Returns immediately when no events are outstanding. The amount of	1804	reason. Returns immediately when no events are outstanding. The amount
1761	events processed depends on the settings of C<IO::AIO::max_poll_req> and	1805	of events processed depends on the settings of C<IO::AIO::max_poll_req>,
1762	C<IO::AIO::max_poll_time>.	1806	C<IO::AIO::max_poll_time> and C<IO::AIO::max_outstanding>.
1763		1807
1764	If not all requests were processed for whatever reason, the filehandle	1808	If not all requests were processed for whatever reason, the poll file
1765	will still be ready when C<poll_cb> returns, so normally you don't have to	1809	descriptor will still be ready when C<poll_cb> returns, so normally you
1766	do anything special to have it called later.	1810	don't have to do anything special to have it called later.
1767		1811
1768	Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes	1812	Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes
1769	ready, it can be beneficial to call this function from loops which submit	1813	ready, it can be beneficial to call this function from loops which submit
1770	a lot of requests, to make sure the results get processed when they become	1814	a lot of requests, to make sure the results get processed when they become
1771	available and not just when the loop is finished and the event loop takes	1815	available and not just when the loop is finished and the event loop takes
…		…
1780	poll => 'r', async => 1,	1824	poll => 'r', async => 1,
1781	cb => \&IO::AIO::poll_cb);	1825	cb => \&IO::AIO::poll_cb);
1782		1826
1783	=item IO::AIO::poll_wait	1827	=item IO::AIO::poll_wait
1784		1828
1785	If there are any outstanding requests and none of them in the result	1829	Wait until either at least one request is in the result phase or no
1786	phase, wait till the result filehandle becomes ready for reading (simply	1830	requests are outstanding anymore.
1787	does a C<select> on the filehandle. This is useful if you want to	1831
1788	synchronously wait for some requests to finish).	1832	This is useful if you want to synchronously wait for some requests to
		1833	become ready, without actually handling them.
1789		1834
1790	See C<nreqs> for an example.	1835	See C<nreqs> for an example.
1791		1836
1792	=item IO::AIO::poll	1837	=item IO::AIO::poll
1793		1838
…		…
1914		1959
1915	This is a very bad function to use in interactive programs because it	1960	This is a very bad function to use in interactive programs because it
1916	blocks, and a bad way to reduce concurrency because it is inexact: Better	1961	blocks, and a bad way to reduce concurrency because it is inexact: Better
1917	use an C<aio_group> together with a feed callback.	1962	use an C<aio_group> together with a feed callback.
1918		1963
1919	It's main use is in scripts without an event loop - when you want to stat	1964	Its main use is in scripts without an event loop - when you want to stat
1920	a lot of files, you can write somehting like this:	1965	a lot of files, you can write somehting like this:
1921		1966
1922	IO::AIO::max_outstanding 32;	1967	IO::AIO::max_outstanding 32;
1923		1968
1924	for my $path (...) {	1969	for my $path (...) {
…		…
1964		2009
1965	=back	2010	=back
1966		2011
1967	=head3 MISCELLANEOUS FUNCTIONS	2012	=head3 MISCELLANEOUS FUNCTIONS
1968		2013
1969	IO::AIO implements some functions that might be useful, but are not	2014	IO::AIO implements some functions that are useful when you want to use
1970	asynchronous.	2015	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_*>
		2017	counterpart.
1971		2018
1972	=over 4	2019	=over 4
1973		2020
1974	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count	2021	=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
1975		2022
…		…
2034	filesize.	2081	filesize.
2035		2082
2036	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,	2083	C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>,
2037	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,	2084	C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>,
2038		2085
2039	C<$flags> can be a combination of C<IO::AIO::MAP_SHARED> or	2086	C<$flags> can be a combination of
2040	C<IO::AIO::MAP_PRIVATE>, or a number of system-specific flags (when	2087	C<IO::AIO::MAP_SHARED> or
2041	not available, the are defined as 0): C<IO::AIO::MAP_ANONYMOUS>	2088	C<IO::AIO::MAP_PRIVATE>,
		2089	or a number of system-specific flags (when not available, the are C<0>):
2042	(which is set to C<MAP_ANON> if your system only provides this	2090	C<IO::AIO::MAP_ANONYMOUS> (which is set to C<MAP_ANON> if your system only provides this constant),
2043	constant), C<IO::AIO::MAP_HUGETLB>, C<IO::AIO::MAP_LOCKED>,	2091	C<IO::AIO::MAP_LOCKED>,
2044	C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or	2092	C<IO::AIO::MAP_NORESERVE>,
		2093	C<IO::AIO::MAP_POPULATE>,
2045	C<IO::AIO::MAP_NONBLOCK>	2094	C<IO::AIO::MAP_NONBLOCK>,
		2095	C<IO::AIO::MAP_FIXED>,
		2096	C<IO::AIO::MAP_GROWSDOWN>,
		2097	C<IO::AIO::MAP_32BIT>,
		2098	C<IO::AIO::MAP_HUGETLB> or
		2099	C<IO::AIO::MAP_STACK>.
2046		2100
2047	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.	2101	If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed.
2048		2102
2049	C<$offset> is the offset from the start of the file - it generally must be	2103	C<$offset> is the offset from the start of the file - it generally must be
2050	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.	2104	a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>.
…		…
2093		2147
2094	See the C<splice(2)> manpage for details.	2148	See the C<splice(2)> manpage for details.
2095		2149
2096	=item IO::AIO::tee $r_fh, $w_fh, $length, $flags	2150	=item IO::AIO::tee $r_fh, $w_fh, $length, $flags
2097		2151
2098	Calls the GNU/Linux C<tee(2)> syscall, see it's manpage and the	2152	Calls the GNU/Linux C<tee(2)> syscall, see its manpage and the
2099	description for C<IO::AIO::splice> above for details.	2153	description for C<IO::AIO::splice> above for details.
		2154
		2155	=item $actual_size = IO::AIO::pipesize $r_fh[, $new_size]
		2156
		2157	Attempts to query or change the pipe buffer size. Obviously works only
		2158	on pipes, and currently works only on GNU/Linux systems, and fails with
		2159	C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer
		2160	size on other systems, drop me a note.
		2161
		2162	=item ($rfh, $wfh) = IO::AIO::pipe2 [$flags]
		2163
		2164	This is a direct interface to the Linux L<pipe2(2)> system call. If
		2165	C<$flags> is missing or C<0>, then this should be the same as a call to
		2166	perl's built-in C<pipe> function and create a new pipe, and works on
		2167	systems that lack the pipe2 syscall. On win32, this case invokes C<_pipe
		2168	(..., 4096, O_BINARY)>.
		2169
		2170	If C<$flags> is non-zero, it tries to invoke the pipe2 system call with
		2171	the given flags (Linux 2.6.27, glibc 2.9).
		2172
		2173	On success, the read and write file handles are returned.
		2174
		2175	On error, nothing will be returned. If the pipe2 syscall is missing and
		2176	C<$flags> is non-zero, fails with C<ENOSYS>.
		2177
		2178	Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the
		2179	time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and
		2180	C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported.
2100		2181
2101	=back	2182	=back
2102		2183
2103	=cut	2184	=cut
2104		2185

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Comparing IO-AIO/AIO.pm (file contents): Revision 1.237 by root, Thu Oct 11 03:20:52 2012 UTC vs. Revision 1.262 by root, Thu Jun 9 03:15:37 2016 UTC

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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.237 by root, Thu Oct 11 03:20:52 2012 UTC vs.
Revision 1.262 by root, Thu Jun 9 03:15:37 2016 UTC