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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.27 by root, Tue Aug 16 22:22:18 2005 UTC vs.
Revision 1.33 by root, Wed Aug 17 06:12:10 2005 UTC

63use base 'Exporter'; 63use base 'Exporter';
64 64
65use Fcntl (); 65use Fcntl ();
66 66
67BEGIN { 67BEGIN {
68 $VERSION = 1.1; 68 $VERSION = 1.4;
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
88syscall has been executed asynchronously. 88syscall has been executed asynchronously.
89 89
90All functions expecting a filehandle keep a copy of the filehandle 90All functions expecting a filehandle keep a copy of the filehandle
91internally until the request has finished. 91internally until the request has finished.
92 92
93The filenames you pass to these routines I<must> be absolute. The reason 93The pathnames you pass to these routines I<must> be absolute and
94for this is that at the time the request is being executed, the current 94encoded in byte form. The reason for the former is that at the time the
95working directory could have changed. Alternatively, you can make sure 95request is being executed, the current working directory could have
96that you never change the current working directory. 96changed. Alternatively, you can make sure that you never change the
97current working directory.
98
99To encode pathnames to byte form, either make sure you either: a)
100always pass in filenames you got from outside (command line, readdir
101etc.), b) are ASCII or ISO 8859-1, c) use the Encode module and encode
102your pathnames to the locale (or other) encoding in effect in the user
103environment, d) use Glib::filename_from_unicode on unicode filenames or e)
104use something else.
97 105
98=over 4 106=over 4
99 107
100=item aio_open $pathname, $flags, $mode, $callback 108=item aio_open $pathname, $flags, $mode, $callback
101 109
142Reads or writes C<length> bytes from the specified C<fh> and C<offset> 150Reads or writes C<length> bytes from the specified C<fh> and C<offset>
143into the scalar given by C<data> and offset C<dataoffset> and calls the 151into the scalar given by C<data> and offset C<dataoffset> and calls the
144callback without the actual number of bytes read (or -1 on error, just 152callback without the actual number of bytes read (or -1 on error, just
145like the syscall). 153like the syscall).
146 154
155The C<$data> scalar I<MUST NOT> be modified in any way while the request
156is outstanding. Modifying it can result in segfaults or WW3 (if the
157necessary/optional hardware is installed).
158
147Example: Read 15 bytes at offset 7 into scalar C<$buffer>, starting at 159Example: Read 15 bytes at offset 7 into scalar C<$buffer>, starting at
148offset C<0> within the scalar: 160offset C<0> within the scalar:
149 161
150 aio_read $fh, 7, 15, $buffer, 0, sub { 162 aio_read $fh, 7, 15, $buffer, 0, sub {
151 $_[0] > 0 or die "read error: $!"; 163 $_[0] > 0 or die "read error: $!";
341 353
3421; 3541;
343 355
344=head2 FORK BEHAVIOUR 356=head2 FORK BEHAVIOUR
345 357
346IO::AIO handles all outstanding AIO requests before the fork, destroys all 358Before the fork IO::AIO enters a quiescent state where no requests can be
347AIO threads, and recreates them in both the parent and the child after the 359added in other threads and no results will be processed. After the fork
348fork. 360the parent simply leaves the quiescent state and continues request/result
349 361processing, while the child clears the request/result queue and starts the
362same number of threads as were in use by the parent.
350 363
351=head1 SEE ALSO 364=head1 SEE ALSO
352 365
353L<Coro>, L<Linux::AIO>. 366L<Coro>, L<Linux::AIO>.
354 367

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