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

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.22 by root, Wed Jul 20 21:55:27 2005 UTC vs.
Revision 1.32 by root, Wed Aug 17 05:26:20 2005 UTC

…		…
56		56
57	=cut	57	=cut
58		58
59	package IO::AIO;	59	package IO::AIO;
60		60
		61	no warnings;
		62
61	use base 'Exporter';	63	use base 'Exporter';
62		64
63	use Fcntl ();	65	use Fcntl ();
64		66
65	BEGIN {	67	BEGIN {
66	$VERSION = 0.9;	68	$VERSION = 1.3;
		69
67		70
68	@EXPORT = qw(aio_read aio_write aio_open aio_close aio_stat aio_lstat aio_unlink	71	@EXPORT = qw(aio_read aio_write aio_open aio_close aio_stat aio_lstat aio_unlink
69	aio_fsync aio_fdatasync aio_readahead);	72	aio_rmdir aio_symlink aio_fsync aio_fdatasync aio_readahead);
70	@EXPORT_OK = qw(poll_fileno poll_cb min_parallel max_parallel max_outstanding nreqs);	73	@EXPORT_OK = qw(poll_fileno poll_cb min_parallel max_parallel max_outstanding nreqs);
71		74
72	require XSLoader;	75	require XSLoader;
73	XSLoader::load IO::AIO, $VERSION;	76	XSLoader::load IO::AIO, $VERSION;
74	}	77	}
…		…
83	which must be a code reference. This code reference will get called with	86	which must be a code reference. This code reference will get called with
84	the syscall return code (e.g. most syscalls return C<-1> on error, unlike	87	the syscall return code (e.g. most syscalls return C<-1> on error, unlike
85	perl, which usually delivers "false") as it's sole argument when the given	88	perl, which usually delivers "false") as it's sole argument when the given
86	syscall has been executed asynchronously.	89	syscall has been executed asynchronously.
87		90
88	All functions that expect a filehandle will also accept a file descriptor.	91	All functions expecting a filehandle keep a copy of the filehandle
		92	internally until the request has finished.
89		93
90	The filenames you pass to these routines I<must> be absolute. The reason	94	The pathnames you pass to these routines I<must> be absolute and
91	for this is that at the time the request is being executed, the current	95	encoded in byte form. The reason for the former is that at the time the
92	working directory could have changed. Alternatively, you can make sure	96	request is being executed, the current working directory could have
93	that you never change the current working directory.	97	changed. Alternatively, you can make sure that you never change the
		98	current working directory.
		99
		100	To encode pathnames to byte form, either make sure you either: a)
		101	always pass in filenames you got from outside (command line, readdir
		102	etc.), b) are ASCII or ISO 8859-1, c) use the Encode module and encode
		103	your pathnames to the locale (or other) encoding in effect in the user
		104	environment, d) use Glib::filename_from_unicode on unicode filenames or e)
		105	use something else.
94		106
95	=over 4	107	=over 4
96		108
97	=item aio_open $pathname, $flags, $mode, $callback	109	=item aio_open $pathname, $flags, $mode, $callback
98		110
…		…
139	Reads or writes C<length> bytes from the specified C<fh> and C<offset>	151	Reads or writes C<length> bytes from the specified C<fh> and C<offset>
140	into the scalar given by C<data> and offset C<dataoffset> and calls the	152	into the scalar given by C<data> and offset C<dataoffset> and calls the
141	callback without the actual number of bytes read (or -1 on error, just	153	callback without the actual number of bytes read (or -1 on error, just
142	like the syscall).	154	like the syscall).
143		155
		156	The C<$data> scalar I<MUST NOT> be modified in any way while the request
		157	is outstanding. Modifying it can result in segfaults or WW3 (if the
		158	necessary/optional hardware is installed).
		159
144	Example: Read 15 bytes at offset 7 into scalar C<$buffer>, starting at	160	Example: Read 15 bytes at offset 7 into scalar C<$buffer>, starting at
145	offset C<0> within the scalar:	161	offset C<0> within the scalar:
146		162
147	aio_read $fh, 7, 15, $buffer, 0, sub {	163	aio_read $fh, 7, 15, $buffer, 0, sub {
148	$_[0] > 0 or die "read error: $!";	164	$_[0] > 0 or die "read error: $!";
149	print "read $_[0] bytes: <$buffer>\n";	165	print "read $_[0] bytes: <$buffer>\n";
150	};	166	};
151		167
152	=item aio_readahead $fh,$offset,$length, $callback	168	=item aio_readahead $fh,$offset,$length, $callback
153
154	Asynchronously reads the specified byte range into the page cache, using
155	the C<readahead> syscall. If that syscall doesn't exist (likely if your OS
156	isn't Linux) the status will be C<-1> and C<$!> is set to C<ENOSYS>.
157		169
158	C<aio_readahead> populates the page cache with data from a file so that	170	C<aio_readahead> populates the page cache with data from a file so that
159	subsequent reads from that file will not block on disk I/O. The C<$offset>	171	subsequent reads from that file will not block on disk I/O. The C<$offset>
160	argument specifies the starting point from which data is to be read and	172	argument specifies the starting point from which data is to be read and
161	C<$length> specifies the number of bytes to be read. I/O is performed in	173	C<$length> specifies the number of bytes to be read. I/O is performed in
162	whole pages, so that offset is effectively rounded down to a page boundary	174	whole pages, so that offset is effectively rounded down to a page boundary
163	and bytes are read up to the next page boundary greater than or equal to	175	and bytes are read up to the next page boundary greater than or equal to
164	(off-set+length). C<aio_readahead> does not read beyond the end of the	176	(off-set+length). C<aio_readahead> does not read beyond the end of the
165	file. The current file offset of the file is left unchanged.	177	file. The current file offset of the file is left unchanged.
166		178
		179	If that syscall doesn't exist (likely if your OS isn't Linux) it will be
		180	emulated by simply reading the data, which would have a similar effect.
		181
167	=item aio_stat $fh_or_path, $callback	182	=item aio_stat $fh_or_path, $callback
168		183
169	=item aio_lstat $fh, $callback	184	=item aio_lstat $fh, $callback
170		185
171	Works like perl's C<stat> or C<lstat> in void context. The callback will	186	Works like perl's C<stat> or C<lstat> in void context. The callback will
…		…
189	=item aio_unlink $pathname, $callback	204	=item aio_unlink $pathname, $callback
190		205
191	Asynchronously unlink (delete) a file and call the callback with the	206	Asynchronously unlink (delete) a file and call the callback with the
192	result code.	207	result code.
193		208
		209	=item aio_rmdir $pathname, $callback
		210
		211	Asynchronously rmdir (delete) a directory and call the callback with the
		212	result code.
		213
194	=item aio_fsync $fh, $callback	214	=item aio_fsync $fh, $callback
195		215
196	Asynchronously call fsync on the given filehandle and call the callback	216	Asynchronously call fsync on the given filehandle and call the callback
197	with the fsync result code.	217	with the fsync result code.
198		218
199	=item aio_fdatasync $fh, $callback	219	=item aio_fdatasync $fh, $callback
200		220
201	Asynchronously call fdatasync on the given filehandle and call the	221	Asynchronously call fdatasync on the given filehandle and call the
202	callback with the fdatasync result code. Might set C<$!> to C<ENOSYS> if	222	callback with the fdatasync result code.
203	C<fdatasync> is not available.	223
		224	If this call isn't available because your OS lacks it or it couldn't be
		225	detected, it will be emulated by calling C<fsync> instead.
204		226
205	=back	227	=back
206		228
207	=head2 SUPPORT FUNCTIONS	229	=head2 SUPPORT FUNCTIONS
208		230
…		…
310		332
311	# support function to convert a fd into a perl filehandle	333	# support function to convert a fd into a perl filehandle
312	sub _fd2fh {	334	sub _fd2fh {
313	return undef if $_[0] < 0;	335	return undef if $_[0] < 0;
314		336
315	# try to be perl5.6-compatible	337	# try to generate nice filehandles
316	local *AIO_FH;	338	my $sym = "IO::AIO::fd#$_[0]";
317	open AIO_FH, "+<&=$_[0]"	339	local *$sym;
		340
		341	open *$sym, "+<&=$_[0]" # usually works under any unix
		342	or open *$sym, "<&=$_[0]" # cygwin needs this
		343	or open *$sym, ">&=$_[0]" # or this
318	or return undef;	344	or return undef;
319		345
320	*AIO_FH	346	*$sym
321	}	347	}
322		348
323	min_parallel 4;	349	min_parallel 4;
324		350
325	END {	351	END {
326	max_parallel 0;	352	max_parallel 0;
327	}	353	}
328		354
329	1;	355	1;
330		356
		357	=head2 FORK BEHAVIOUR
		358
		359	Before the fork IO::AIO enters a quiescent state where no requests can be
		360	added in other threads and no results will be processed. After the fork
		361	the parent simply leaves the quiescent state and continues request/result
		362	processing, while the child clears the request/result queue and starts the
		363	same number of threads as were in use by the parent.
		364
331	=head1 SEE ALSO	365	=head1 SEE ALSO
332		366
333	L<Coro>, L<Linux::AIO>.	367	L<Coro>, L<Linux::AIO>.
334		368
335	=head1 AUTHOR	369	=head1 AUTHOR

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Comparing IO-AIO/AIO.pm (file contents): Revision 1.22 by root, Wed Jul 20 21:55:27 2005 UTC vs. Revision 1.32 by root, Wed Aug 17 05:26:20 2005 UTC

Diff Legend

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.22 by root, Wed Jul 20 21:55:27 2005 UTC vs.
Revision 1.32 by root, Wed Aug 17 05:26:20 2005 UTC