[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 1.31 by root, Wed Aug 17 05:06:59 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 = 1.2;
67		69
68	@EXPORT = qw(aio_read aio_write aio_open aio_close aio_stat aio_lstat aio_unlink	70	@EXPORT = qw(aio_read aio_write aio_open aio_close aio_stat aio_lstat aio_unlink
69	aio_fsync aio_fdatasync aio_readahead);	71	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);	72	@EXPORT_OK = qw(poll_fileno poll_cb min_parallel max_parallel max_outstanding nreqs);
71		73
72	require XSLoader;	74	require XSLoader;
73	XSLoader::load IO::AIO, $VERSION;	75	XSLoader::load IO::AIO, $VERSION;
74	}	76	}
…		…
83	which must be a code reference. This code reference will get called with	85	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	86	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	87	perl, which usually delivers "false") as it's sole argument when the given
86	syscall has been executed asynchronously.	88	syscall has been executed asynchronously.
87		89
88	All functions that expect a filehandle will also accept a file descriptor.	90	All functions expecting a filehandle keep a copy of the filehandle
		91	internally until the request has finished.
89		92
90	The filenames you pass to these routines I<must> be absolute. The reason	93	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	94	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	95	request is being executed, the current working directory could have
93	that you never change the current working directory.	96	changed. Alternatively, you can make sure that you never change the
		97	current working directory.
		98
		99	To encode pathnames to byte form, either make sure you either: a)
		100	always pass in filenames you got from outside (command line, readdir
		101	etc.), b) are ASCII or ISO 8859-1, c) use the Encode module and encode
		102	your pathnames to the locale (or other) encoding in effect in the user
		103	environment, d) use Glib::filename_from_unicode on unicode filenames or e)
		104	use something else.
94		105
95	=over 4	106	=over 4
96		107
97	=item aio_open $pathname, $flags, $mode, $callback	108	=item aio_open $pathname, $flags, $mode, $callback
98		109
…		…
139	Reads or writes C<length> bytes from the specified C<fh> and C<offset>	150	Reads or writes C<length> bytes from the specified C<fh> and C<offset>
140	into the scalar given by C<data> and offset C<dataoffset> and calls the	151	into the scalar given by C<data> and offset C<dataoffset> and calls the
141	callback without the actual number of bytes read (or -1 on error, just	152	callback without the actual number of bytes read (or -1 on error, just
142	like the syscall).	153	like the syscall).
143		154
		155	The C<$data> scalar I<MUST NOT> be modified in any way while the request
		156	is outstanding. Modifying it can result in segfaults or WW3 (if the
		157	necessary/optional hardware is installed).
		158
144	Example: Read 15 bytes at offset 7 into scalar C<$buffer>, starting at	159	Example: Read 15 bytes at offset 7 into scalar C<$buffer>, starting at
145	offset C<0> within the scalar:	160	offset C<0> within the scalar:
146		161
147	aio_read $fh, 7, 15, $buffer, 0, sub {	162	aio_read $fh, 7, 15, $buffer, 0, sub {
148	$_[0] > 0 or die "read error: $!";	163	$_[0] > 0 or die "read error: $!";
149	print "read $_[0] bytes: <$buffer>\n";	164	print "read $_[0] bytes: <$buffer>\n";
150	};	165	};
151		166
152	=item aio_readahead $fh,$offset,$length, $callback	167	=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		168
158	C<aio_readahead> populates the page cache with data from a file so that	169	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<$offset>	170	subsequent reads from that file will not block on disk I/O. The C<$offset>
160	argument specifies the starting point from which data is to be read and	171	argument specifies the starting point from which data is to be read and
161	C<$length> specifies the number of bytes to be read. I/O is performed in	172	C<$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	173	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	174	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	175	(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.	176	file. The current file offset of the file is left unchanged.
166		177
		178	If that syscall doesn't exist (likely if your OS isn't Linux) it will be
		179	emulated by simply reading the data, which would have a similar effect.
		180
167	=item aio_stat $fh_or_path, $callback	181	=item aio_stat $fh_or_path, $callback
168		182
169	=item aio_lstat $fh, $callback	183	=item aio_lstat $fh, $callback
170		184
171	Works like perl's C<stat> or C<lstat> in void context. The callback will	185	Works like perl's C<stat> or C<lstat> in void context. The callback will
…		…
189	=item aio_unlink $pathname, $callback	203	=item aio_unlink $pathname, $callback
190		204
191	Asynchronously unlink (delete) a file and call the callback with the	205	Asynchronously unlink (delete) a file and call the callback with the
192	result code.	206	result code.
193		207
		208	=item aio_rmdir $pathname, $callback
		209
		210	Asynchronously rmdir (delete) a directory and call the callback with the
		211	result code.
		212
194	=item aio_fsync $fh, $callback	213	=item aio_fsync $fh, $callback
195		214
196	Asynchronously call fsync on the given filehandle and call the callback	215	Asynchronously call fsync on the given filehandle and call the callback
197	with the fsync result code.	216	with the fsync result code.
198		217
199	=item aio_fdatasync $fh, $callback	218	=item aio_fdatasync $fh, $callback
200		219
201	Asynchronously call fdatasync on the given filehandle and call the	220	Asynchronously call fdatasync on the given filehandle and call the
202	callback with the fdatasync result code. Might set C<$!> to C<ENOSYS> if	221	callback with the fdatasync result code.
203	C<fdatasync> is not available.	222
		223	If this call isn't available because your OS lacks it or it couldn't be
		224	detected, it will be emulated by calling C<fsync> instead.
204		225
205	=back	226	=back
206		227
207	=head2 SUPPORT FUNCTIONS	228	=head2 SUPPORT FUNCTIONS
208		229
…		…
310		331
311	# support function to convert a fd into a perl filehandle	332	# support function to convert a fd into a perl filehandle
312	sub _fd2fh {	333	sub _fd2fh {
313	return undef if $_[0] < 0;	334	return undef if $_[0] < 0;
314		335
315	# try to be perl5.6-compatible	336	# try to generate nice filehandles
316	local *AIO_FH;	337	my $sym = "IO::AIO::fd#$_[0]";
317	open AIO_FH, "+<&=$_[0]"	338	local *$sym;
		339
		340	open *$sym, "+<&=$_[0]" # usually works under any unix
		341	or open *$sym, "<&=$_[0]" # cygwin needs this
		342	or open *$sym, ">&=$_[0]" # or this
318	or return undef;	343	or return undef;
319		344
320	*AIO_FH	345	*$sym
321	}	346	}
322		347
323	min_parallel 4;	348	min_parallel 4;
324		349
325	END {	350	END {
326	max_parallel 0;	351	max_parallel 0;
327	}	352	}
328		353
329	1;	354	1;
330		355
		356	=head2 FORK BEHAVIOUR
		357
		358	Before the fork IO::AIO enters a quiescent state where no requests can be
		359	added in other threads and no results will be processed. After the fork
		360	the parent simply leaves the quiescent state and continues request/result
		361	processing, while the child clears the request/result queue and starts the
		362	same number of threads as were in use by the parent.
		363
331	=head1 SEE ALSO	364	=head1 SEE ALSO
332		365
333	L<Coro>, L<Linux::AIO>.	366	L<Coro>, L<Linux::AIO>.
334		367
335	=head1 AUTHOR	368	=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 1.31 by root, Wed Aug 17 05:06:59 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 1.31 by root, Wed Aug 17 05:06:59 2005 UTC