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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.109 by root, Sun Jun 3 09:44:17 2007 UTC vs.
Revision 1.116 by root, Wed Oct 3 21:27:51 2007 UTC

189use strict 'vars'; 189use strict 'vars';
190 190
191use base 'Exporter'; 191use base 'Exporter';
192 192
193BEGIN { 193BEGIN {
194 our $VERSION = '2.4'; 194 our $VERSION = '2.5';
195 195
196 our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close aio_stat 196 our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close aio_stat
197 aio_lstat aio_unlink aio_rmdir aio_readdir aio_scandir aio_symlink 197 aio_lstat aio_unlink aio_rmdir aio_readdir aio_scandir aio_symlink
198 aio_readlink aio_fsync aio_fdatasync aio_readahead aio_rename aio_link 198 aio_readlink aio_fsync aio_fdatasync aio_readahead aio_rename aio_link
199 aio_move aio_copy aio_group aio_nop aio_mknod aio_load aio_rmtree aio_mkdir 199 aio_move aio_copy aio_group aio_nop aio_mknod aio_load aio_rmtree aio_mkdir
200 aio_chown aio_chmod aio_utime); 200 aio_chown aio_chmod aio_utime aio_truncate);
201 our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice aio_block)); 201 our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice aio_block));
202 our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush 202 our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush
203 min_parallel max_parallel max_idle 203 min_parallel max_parallel max_idle
204 nreqs nready npending nthreads 204 nreqs nready npending nthreads
205 max_poll_time max_poll_reqs); 205 max_poll_time max_poll_reqs);
311 311
312 312
313=item aio_close $fh, $callback->($status) 313=item aio_close $fh, $callback->($status)
314 314
315Asynchronously close a file and call the callback with the result 315Asynchronously close a file and call the callback with the result
316code. I<WARNING:> although accepted, you should not pass in a perl 316code.
317filehandle here, as perl will likely close the file descriptor another
318time when the filehandle is destroyed. Normally, you can safely call perls
319C<close> or just let filehandles go out of scope.
320 317
321This is supposed to be a bug in the API, so that might change. It's 318Unlike the other functions operating on files, this function uses the
322therefore best to avoid this function. 319PerlIO layer to close the filehandle. The reason is that the PerlIO API
320insists on closing the underlying fd itself, no matter what, and doesn't
321allow modifications to the fd. Unfortunately, it is not clear that you can
322call PerlIO from different threads (actually, its quite clear that this
323won't work in some cases), so while it likely works perfectly with simple
324file handles (such as the ones created by C<aio_open>) it might fail in
325interesting ways for others.
326
327Having said that, aio_close tries to clean up the filehandle as much as
328possible before handing it to an io thread, and generally does work.
323 329
324 330
325=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) 331=item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
326 332
327=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) 333=item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
329Reads or writes C<$length> bytes from the specified C<$fh> and C<$offset> 335Reads or writes C<$length> bytes from the specified C<$fh> and C<$offset>
330into the scalar given by C<$data> and offset C<$dataoffset> and calls the 336into the scalar given by C<$data> and offset C<$dataoffset> and calls the
331callback without the actual number of bytes read (or -1 on error, just 337callback without the actual number of bytes read (or -1 on error, just
332like the syscall). 338like the syscall).
333 339
334If C<$offset> is undefined, then the current file offset will be used (and 340If C<$offset> is undefined, then the current file descriptor offset will
335updated), otherwise the file offset will not be changed by these calls. 341be used (and updated), otherwise the file descriptor offset will not be
342changed by these calls.
336 343
337If C<$length> is undefined in C<aio_write>, use the remaining length of C<$data>. 344If C<$length> is undefined in C<aio_write>, use the remaining length of C<$data>.
338 345
339If C<$dataoffset> is less than zero, it will be counted from the end of 346If C<$dataoffset> is less than zero, it will be counted from the end of
340C<$data>. 347C<$data>.
341 348
342The C<$data> scalar I<MUST NOT> be modified in any way while the request 349The C<$data> scalar I<MUST NOT> be modified in any way while the request
441 448
442 # same as "chown root path" in the shell: 449 # same as "chown root path" in the shell:
443 aio_chown "path", 0, -1; 450 aio_chown "path", 0, -1;
444 # same as above: 451 # same as above:
445 aio_chown "path", 0, undef; 452 aio_chown "path", 0, undef;
453
454
455=item aio_truncate $fh_or_path, $offset, $callback->($status)
456
457Works like truncate(2) or ftruncate(2).
446 458
447 459
448=item aio_chmod $fh_or_path, $mode, $callback->($status) 460=item aio_chmod $fh_or_path, $mode, $callback->($status)
449 461
450Works like perl's C<chmod> function. 462Works like perl's C<chmod> function.
1201This is a very bad function to use in interactive programs because it 1213This is a very bad function to use in interactive programs because it
1202blocks, and a bad way to reduce concurrency because it is inexact: Better 1214blocks, and a bad way to reduce concurrency because it is inexact: Better
1203use an C<aio_group> together with a feed callback. 1215use an C<aio_group> together with a feed callback.
1204 1216
1205Sets the maximum number of outstanding requests to C<$nreqs>. If you 1217Sets the maximum number of outstanding requests to C<$nreqs>. If you
1206to queue up more than this number of requests, the next call to the 1218do queue up more than this number of requests, the next call to the
1207C<poll_cb> (and C<poll_some> and other functions calling C<poll_cb>) 1219C<poll_cb> (and C<poll_some> and other functions calling C<poll_cb>)
1208function will block until the limit is no longer exceeded. 1220function will block until the limit is no longer exceeded.
1209 1221
1210The default value is very large, so there is no practical limit on the 1222The default value is very large, so there is no practical limit on the
1211number of outstanding requests. 1223number of outstanding requests.
1241but not yet processed by poll_cb). 1253but not yet processed by poll_cb).
1242 1254
1243=back 1255=back
1244 1256
1245=cut 1257=cut
1246
1247# support function to convert a fd into a perl filehandle
1248sub _fd2fh {
1249 return undef if $_[0] < 0;
1250
1251 # try to generate nice filehandles
1252 my $sym = "IO::AIO::fd#$_[0]";
1253 local *$sym;
1254
1255 open *$sym, "+<&=$_[0]" # usually works under any unix
1256 or open *$sym, "<&=$_[0]" # cygwin needs this
1257 or open *$sym, ">&=$_[0]" # or this
1258 or return undef;
1259
1260 *$sym
1261}
1262 1258
1263min_parallel 8; 1259min_parallel 8;
1264 1260
1265END { flush } 1261END { flush }
1266 1262
1290bytes of memory. In addition, stat requests need a stat buffer (possibly 1286bytes of memory. In addition, stat requests need a stat buffer (possibly
1291a few hundred bytes), readdir requires a result buffer and so on. Perl 1287a few hundred bytes), readdir requires a result buffer and so on. Perl
1292scalars and other data passed into aio requests will also be locked and 1288scalars and other data passed into aio requests will also be locked and
1293will consume memory till the request has entered the done state. 1289will consume memory till the request has entered the done state.
1294 1290
1295This is now awfully much, so queuing lots of requests is not usually a 1291This is not awfully much, so queuing lots of requests is not usually a
1296problem. 1292problem.
1297 1293
1298Per-thread usage: 1294Per-thread usage:
1299 1295
1300In the execution phase, some aio requests require more memory for 1296In the execution phase, some aio requests require more memory for

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