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Revision 1.7 by root, Sun Jul 10 22:19:54 2005 UTC vs.
Revision 1.21 by root, Wed Jul 13 00:13:09 2005 UTC

… …
12 }; 12 };
13 13
14 aio_unlink "/tmp/file", sub { }; 14 aio_unlink "/tmp/file", sub { };
15 15
16 aio_read $fh, 30000, 1024, $buffer, 0, sub { 16 aio_read $fh, 30000, 1024, $buffer, 0, sub {
17 $_[0] >= 0 or die "read error: $!"; 17 $_[0] > 0 or die "read error: $!";
18 }; 18 };
19 19
20 # Event 20 # Event
21 Event->io (fd => IO::AIO::poll_fileno, 21 Event->io (fd => IO::AIO::poll_fileno,
22 poll => 'r', 22 poll => 'r',
23 cb => \&IO::AIO::poll_cb); 23 cb => \&IO::AIO::poll_cb);
24 24
25 # Glib/Gtk2 25 # Glib/Gtk2
26 add_watch Glib::IO IO::AIO::poll_fileno, 26 add_watch Glib::IO IO::AIO::poll_fileno,
27 \&IO::AIO::poll_cb; 27 in => sub { IO::AIO::poll_cb, 1 };
28 28
29 # Tk 29 # Tk
30 Tk::Event::IO->fileevent (IO::AIO::poll_fileno, "", 30 Tk::Event::IO->fileevent (IO::AIO::poll_fileno, "",
31 readable => \&IO::AIO::poll_cb); 31 readable => \&IO::AIO::poll_cb);
32
33 # Danga::Socket
34 Danga::Socket->AddOtherFds (IO::AIO::poll_fileno =>
35 \&IO::AIO::poll_cb);
36
32 37
33=head1 DESCRIPTION 38=head1 DESCRIPTION
34 39
35This module implements asynchronous I/O using whatever means your 40This module implements asynchronous I/O using whatever means your
36operating system supports. 41operating system supports.
… …
54use base 'Exporter'; 59use base 'Exporter';
55 60
56use Fcntl (); 61use Fcntl ();
57 62
58BEGIN { 63BEGIN {
59 $VERSION = 0.2; 64 $VERSION = 0.9;
60 65
61 @EXPORT = qw(aio_read aio_write aio_open aio_close aio_stat aio_lstat aio_unlink 66 @EXPORT = qw(aio_read aio_write aio_open aio_close aio_stat aio_lstat aio_unlink
62 aio_fsync aio_fdatasync aio_readahead); 67 aio_fsync aio_fdatasync aio_readahead);
63 @EXPORT_OK = qw(poll_fileno poll_cb min_parallel max_parallel max_outstanding nreqs); 68 @EXPORT_OK = qw(poll_fileno poll_cb min_parallel max_parallel max_outstanding nreqs);
64 69
… …
70 75
71=head2 AIO FUNCTIONS 76=head2 AIO FUNCTIONS
72 77
73All the C<aio_*> calls are more or less thin wrappers around the syscall 78All the C<aio_*> calls are more or less thin wrappers around the syscall
74with the same name (sans C<aio_>). The arguments are similar or identical, 79with the same name (sans C<aio_>). The arguments are similar or identical,
75and they all accept an additional C<$callback> argument which must be 80and they all accept an additional (and optional) C<$callback> argument
76a code reference. This code reference will get called with the syscall 81which must be a code reference. This code reference will get called with
77return code (e.g. most syscalls return C<-1> on error, unlike perl, which 82the syscall return code (e.g. most syscalls return C<-1> on error, unlike
78usually delivers "false") as it's sole argument when the given syscall has 83perl, which usually delivers "false") as it's sole argument when the given
79been executed asynchronously. 84syscall has been executed asynchronously.
80 85
81All functions that expect a filehandle will also accept a file descriptor. 86All functions that expect a filehandle will also accept a file descriptor.
82 87
83The filenames you pass to these routines I<must> be absolute. The reason 88The filenames you pass to these routines I<must> be absolute. The reason
84is that at the time the request is being executed, the current working 89for this is that at the time the request is being executed, the current
85directory could have changed. Alternatively, you can make sure that you 90working directory could have changed. Alternatively, you can make sure
86never change the current working directory. 91that you never change the current working directory.
87 92
88=over 4 93=over 4
89 94
90=item aio_open $pathname, $flags, $mode, $callback 95=item aio_open $pathname, $flags, $mode, $callback
91 96
… …
93created filehandle for the file. 98created filehandle for the file.
94 99
95The pathname passed to C<aio_open> must be absolute. See API NOTES, above, 100The pathname passed to C<aio_open> must be absolute. See API NOTES, above,
96for an explanation. 101for an explanation.
97 102
98The C<$mode> argument is a bitmask. See the C<Fcntl> module for a 103The C<$flags> argument is a bitmask. See the C<Fcntl> module for a
99list. They are the same as used in C<sysopen>. 104list. They are the same as used by C<sysopen>.
105
106Likewise, C<$mode> specifies the mode of the newly created file, if it
107didn't exist and C<O_CREAT> has been given, just like perl's C<sysopen>,
108except that it is mandatory (i.e. use C<0> if you don't create new files,
109and C<0666> or C<0777> if you do).
100 110
101Example: 111Example:
102 112
103 aio_open "/etc/passwd", O_RDONLY, 0, sub { 113 aio_open "/etc/passwd", O_RDONLY, 0, sub {
104 if ($_[0]) { 114 if ($_[0]) {
… …
111 121
112=item aio_close $fh, $callback 122=item aio_close $fh, $callback
113 123
114Asynchronously close a file and call the callback with the result 124Asynchronously close a file and call the callback with the result
115code. I<WARNING:> although accepted, you should not pass in a perl 125code. I<WARNING:> although accepted, you should not pass in a perl
116filehandle here, as perl will likely close the file descriptor itself when 126filehandle here, as perl will likely close the file descriptor another
117the filehandle is destroyed. Normally, you can safely call perls C<close> 127time when the filehandle is destroyed. Normally, you can safely call perls
118or just let filehandles go out of scope. 128C<close> or just let filehandles go out of scope.
129
130This is supposed to be a bug in the API, so that might change. It's
131therefore best to avoid this function.
119 132
120=item aio_read $fh,$offset,$length, $data,$dataoffset,$callback 133=item aio_read $fh,$offset,$length, $data,$dataoffset,$callback
121 134
122=item aio_write $fh,$offset,$length, $data,$dataoffset,$callback 135=item aio_write $fh,$offset,$length, $data,$dataoffset,$callback
123 136
124Reads or writes C<length> bytes from the specified C<fh> and C<offset> 137Reads or writes C<length> bytes from the specified C<fh> and C<offset>
125into the scalar given by C<data> and offset C<dataoffset> and calls the 138into the scalar given by C<data> and offset C<dataoffset> and calls the
126callback without the actual number of bytes read (or -1 on error, just 139callback without the actual number of bytes read (or -1 on error, just
127like the syscall). 140like the syscall).
128 141
129Example: Read 15 bytes at offset 7 into scalar C<$buffer>, strating at 142Example: Read 15 bytes at offset 7 into scalar C<$buffer>, starting at
130offset C<0> within the scalar: 143offset C<0> within the scalar:
131 144
132 aio_read $fh, 7, 15, $buffer, 0, sub { 145 aio_read $fh, 7, 15, $buffer, 0, sub {
133 $_[0] >= 0 or die "read error: $!"; 146 $_[0] > 0 or die "read error: $!";
134 print "read <$buffer>\n"; 147 print "read $_[0] bytes: <$buffer>\n";
135 }; 148 };
136 149
137=item aio_readahead $fh,$offset,$length, $callback 150=item aio_readahead $fh,$offset,$length, $callback
138 151
139Asynchronously reads the specified byte range into the page cache, using 152Asynchronously reads the specified byte range into the page cache, using
140the C<readahead> syscall. If that syscall doesn't exist the status will be 153the C<readahead> syscall. If that syscall doesn't exist (likely if your OS
141C<-1> and C<$!> is set to ENOSYS. 154isn't Linux) the status will be C<-1> and C<$!> is set to C<ENOSYS>.
142 155
143readahead() populates the page cache with data from a file so that 156C<aio_readahead> populates the page cache with data from a file so that
144subsequent reads from that file will not block on disk I/O. The C<$offset> 157subsequent reads from that file will not block on disk I/O. The C<$offset>
145argument specifies the starting point from which data is to be read and 158argument specifies the starting point from which data is to be read and
146C<$length> specifies the number of bytes to be read. I/O is performed in 159C<$length> specifies the number of bytes to be read. I/O is performed in
147whole pages, so that offset is effectively rounded down to a page boundary 160whole pages, so that offset is effectively rounded down to a page boundary
148and bytes are read up to the next page boundary greater than or equal to 161and bytes are read up to the next page boundary greater than or equal to
149(off-set+length). aio_readahead() does not read beyond the end of the 162(off-set+length). C<aio_readahead> does not read beyond the end of the
150file. The current file offset of the file is left unchanged. 163file. The current file offset of the file is left unchanged.
151 164
152=item aio_stat $fh_or_path, $callback 165=item aio_stat $fh_or_path, $callback
153 166
154=item aio_lstat $fh, $callback 167=item aio_lstat $fh, $callback
… …
182with the fsync result code. 195with the fsync result code.
183 196
184=item aio_fdatasync $fh, $callback 197=item aio_fdatasync $fh, $callback
185 198
186Asynchronously call fdatasync on the given filehandle and call the 199Asynchronously call fdatasync on the given filehandle and call the
187callback with the fdatasync result code. 200callback with the fdatasync result code. Might set C<$!> to C<ENOSYS> if
201C<fdatasync> is not available.
188 202
189=back 203=back
190 204
191=head2 SUPPORT FUNCTIONS 205=head2 SUPPORT FUNCTIONS
192 206
193=over 4 207=over 4
194 208
195=item $fileno = IO::AIO::poll_fileno 209=item $fileno = IO::AIO::poll_fileno
196 210
197Return the I<request result pipe filehandle>. This filehandle must be 211Return the I<request result pipe file descriptor>. This filehandle must be
198polled for reading by some mechanism outside this module (e.g. Event 212polled for reading by some mechanism outside this module (e.g. Event or
199or select, see below). If the pipe becomes readable you have to call 213select, see below or the SYNOPSIS). If the pipe becomes readable you have
200C<poll_cb> to check the results. 214to call C<poll_cb> to check the results.
201 215
202See C<poll_cb> for an example. 216See C<poll_cb> for an example.
203 217
204=item IO::AIO::poll_cb 218=item IO::AIO::poll_cb
205 219
206Process all outstanding events on the result pipe. You have to call this 220Process all outstanding events on the result pipe. You have to call this
207regularly. Returns the number of events processed. Returns immediately 221regularly. Returns the number of events processed. Returns immediately
208when no events are outstanding. 222when no events are outstanding.
209 223
210You can use Event to multiplex, e.g.: 224Example: Install an Event watcher that automatically calls
225IO::AIO::poll_cb with high priority:
211 226
212 Event->io (fd => IO::AIO::poll_fileno, 227 Event->io (fd => IO::AIO::poll_fileno,
213 poll => 'r', async => 1, 228 poll => 'r', async => 1,
214 cb => \&IO::AIO::poll_cb); 229 cb => \&IO::AIO::poll_cb);
215 230
216=item IO::AIO::poll_wait 231=item IO::AIO::poll_wait
217 232
218Wait till the result filehandle becomes ready for reading (simply does a 233Wait till the result filehandle becomes ready for reading (simply does a
219select on the filehandle. This is useful if you want to synchronously wait 234C<select> on the filehandle. This is useful if you want to synchronously wait
220for some requests to finish). 235for some requests to finish).
221 236
222See C<nreqs> for an example. 237See C<nreqs> for an example.
223 238
224=item IO::AIO::nreqs 239=item IO::AIO::nreqs
225 240
226Returns the number of requests currently outstanding. 241Returns the number of requests currently outstanding (i.e. for which their
242callback has not been invoked yet).
227 243
228Example: wait till there are no outstanding requests anymore: 244Example: wait till there are no outstanding requests anymore:
229 245
230 IO::AIO::poll_wait, IO::AIO::poll_cb 246 IO::AIO::poll_wait, IO::AIO::poll_cb
231 while IO::AIO::nreqs; 247 while IO::AIO::nreqs;
248
249=item IO::AIO::flush
250
251Wait till all outstanding AIO requests have been handled.
252
253Strictly equivalent to:
254
255 IO::AIO::poll_wait, IO::AIO::poll_cb
256 while IO::AIO::nreqs;
257
258=item IO::AIO::poll
259
260Waits until some requests have been handled.
261
262Strictly equivalent to:
263
264 IO::AIO::poll_wait, IO::AIO::poll_cb
265 if IO::AIO::nreqs;
232 266
233=item IO::AIO::min_parallel $nthreads 267=item IO::AIO::min_parallel $nthreads
234 268
235Set the minimum number of AIO threads to C<$nthreads>. The default is 269Set the minimum number of AIO threads to C<$nthreads>. The default is
236C<1>, which means a single asynchronous operation can be done at one time 270C<1>, which means a single asynchronous operation can be done at one time

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