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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 1.26 by root, Sun Aug 7 03:34:07 2005 UTC

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56 56
57=cut 57=cut
58 58
59package IO::AIO; 59package IO::AIO;
60 60
61no warnings;
62
61use base 'Exporter'; 63use base 'Exporter';
62 64
63use Fcntl (); 65use Fcntl ();
64 66
65BEGIN { 67BEGIN {
66 $VERSION = 0.9; 68 $VERSION = 1.1;
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_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
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83which must be a code reference. This code reference will get called with 85which must be a code reference. This code reference will get called with
84the syscall return code (e.g. most syscalls return C<-1> on error, unlike 86the syscall return code (e.g. most syscalls return C<-1> on error, unlike
85perl, which usually delivers "false") as it's sole argument when the given 87perl, which usually delivers "false") as it's sole argument when the given
86syscall has been executed asynchronously. 88syscall has been executed asynchronously.
87 89
88All functions that expect a filehandle will also accept a file descriptor. 90All functions expecting a filehandle keep a copy of the filehandle
91internally until the request has finished.
89 92
90The filenames you pass to these routines I<must> be absolute. The reason 93The filenames you pass to these routines I<must> be absolute. The reason
91for this is that at the time the request is being executed, the current 94for this is that at the time the request is being executed, the current
92working directory could have changed. Alternatively, you can make sure 95working directory could have changed. Alternatively, you can make sure
93that you never change the current working directory. 96that you never change the current working directory.
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149 print "read $_[0] bytes: <$buffer>\n"; 152 print "read $_[0] bytes: <$buffer>\n";
150 }; 153 };
151 154
152=item aio_readahead $fh,$offset,$length, $callback 155=item aio_readahead $fh,$offset,$length, $callback
153 156
154Asynchronously reads the specified byte range into the page cache, using
155the C<readahead> syscall. If that syscall doesn't exist (likely if your OS
156isn't Linux) the status will be C<-1> and C<$!> is set to C<ENOSYS>.
157
158C<aio_readahead> populates the page cache with data from a file so that 157C<aio_readahead> populates the page cache with data from a file so that
159subsequent reads from that file will not block on disk I/O. The C<$offset> 158subsequent reads from that file will not block on disk I/O. The C<$offset>
160argument specifies the starting point from which data is to be read and 159argument specifies the starting point from which data is to be read and
161C<$length> specifies the number of bytes to be read. I/O is performed in 160C<$length> specifies the number of bytes to be read. I/O is performed in
162whole pages, so that offset is effectively rounded down to a page boundary 161whole pages, so that offset is effectively rounded down to a page boundary
163and bytes are read up to the next page boundary greater than or equal to 162and 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 163(off-set+length). C<aio_readahead> does not read beyond the end of the
165file. The current file offset of the file is left unchanged. 164file. The current file offset of the file is left unchanged.
166 165
166If that syscall doesn't exist (likely if your OS isn't Linux) it will be
167emulated by simply reading the data, which would have a similar effect.
168
167=item aio_stat $fh_or_path, $callback 169=item aio_stat $fh_or_path, $callback
168 170
169=item aio_lstat $fh, $callback 171=item aio_lstat $fh, $callback
170 172
171Works like perl's C<stat> or C<lstat> in void context. The callback will 173Works like perl's C<stat> or C<lstat> in void context. The callback will
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197with the fsync result code. 199with the fsync result code.
198 200
199=item aio_fdatasync $fh, $callback 201=item aio_fdatasync $fh, $callback
200 202
201Asynchronously call fdatasync on the given filehandle and call the 203Asynchronously call fdatasync on the given filehandle and call the
202callback with the fdatasync result code. Might set C<$!> to C<ENOSYS> if 204callback with the fdatasync result code.
203C<fdatasync> is not available. 205
206If this call isn't available because your OS lacks it or it couldn't be
207detected, it will be emulated by calling C<fsync> instead.
204 208
205=back 209=back
206 210
207=head2 SUPPORT FUNCTIONS 211=head2 SUPPORT FUNCTIONS
208 212
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310 314
311# support function to convert a fd into a perl filehandle 315# support function to convert a fd into a perl filehandle
312sub _fd2fh { 316sub _fd2fh {
313 return undef if $_[0] < 0; 317 return undef if $_[0] < 0;
314 318
315 # try to be perl5.6-compatible 319 # try to generate nice filehandles
316 local *AIO_FH; 320 my $sym = "IO::AIO::fd#$_[0]";
317 open AIO_FH, "+<&=$_[0]" 321 local *$sym;
322
323 open *$sym, "+<&$_[0]" # usually under any unix
324 or open *$sym, "<&$_[0]" # cygwin needs this
325 or open *$sym, ">&$_[0]" # cygwin needs this
318 or return undef; 326 or return undef;
319 327
320 *AIO_FH 328 *$sym
321} 329}
322 330
323min_parallel 4; 331min_parallel 4;
324 332
325END { 333END {

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