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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.34 by root, Thu Aug 18 16:32:10 2005 UTC vs.
Revision 1.36 by root, Tue Aug 23 00:03:14 2005 UTC

63use base 'Exporter'; 63use base 'Exporter';
64 64
65use Fcntl (); 65use Fcntl ();
66 66
67BEGIN { 67BEGIN {
68 $VERSION = 1.5; 68 $VERSION = 1.6;
69 69
70 @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
71 aio_rmdir aio_symlink aio_fsync aio_fdatasync aio_readahead); 71 aio_rmdir aio_symlink aio_fsync aio_fdatasync aio_readahead);
72 @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);
73 73
162 aio_read $fh, 7, 15, $buffer, 0, sub { 162 aio_read $fh, 7, 15, $buffer, 0, sub {
163 $_[0] > 0 or die "read error: $!"; 163 $_[0] > 0 or die "read error: $!";
164 print "read $_[0] bytes: <$buffer>\n"; 164 print "read $_[0] bytes: <$buffer>\n";
165 }; 165 };
166 166
167=item aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback
168
169Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts
170reading at byte offset C<$in_offset>, and starts writing at the current
171file offset of C<$out_fh>. Because of that, it is not safe to issue more
172than one C<aio_sendfile> per C<$out_fh>, as they will interfere with each
173other.
174
175This call tries to make use of a native C<sendfile> syscall to provide
176zero-copy operation. For this to work, C<$out_fh> should refer to a
177socket, and C<$in_fh> should refer to mmap'able file.
178
179If the native sendfile call fails or is not implemented, it will be
180emulated, so you can call C<aio_sendfile> on any type of filehandle
181regardless of the limitations of the operating system.
182
183Please note, however, that C<aio_sendfile> can read more bytes from
184C<$in_fh> than are written, and there is no way to find out how many
185bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only
186provides the number of bytes written to C<$out_fh>. Only if the result
187value equals C<$length> one can assume that C<$length> bytes have been
188read.
189
167=item aio_readahead $fh,$offset,$length, $callback 190=item aio_readahead $fh,$offset,$length, $callback
168 191
169C<aio_readahead> populates the page cache with data from a file so that 192C<aio_readahead> populates the page cache with data from a file so that
170subsequent reads from that file will not block on disk I/O. The C<$offset> 193subsequent reads from that file will not block on disk I/O. The C<$offset>
171argument specifies the starting point from which data is to be read and 194argument specifies the starting point from which data is to be read and

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