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Revision 1.26 by root, Thu Oct 4 12:50:35 2007 UTC vs.
Revision 1.29 by root, Wed Apr 16 16:45:30 2008 UTC

24 $req->cancel; # cancel request if still in queue 24 $req->cancel; # cancel request if still in queue
25 25
26 my $grp = aio_group sub { print "all stats done\n" }; 26 my $grp = aio_group sub { print "all stats done\n" };
27 add $grp aio_stat "..." for ...; 27 add $grp aio_stat "..." for ...;
28 28
29 # AnyEvent integration 29 # AnyEvent integration (EV, Event, Glib, Tk, urxvt, pureperl...)
30 open my $fh, "<&=" . IO::AIO::poll_fileno or die "$!"; 30 open my $fh, "<&=" . IO::AIO::poll_fileno or die "$!";
31 my $w = AnyEvent->io (fh => $fh, poll => 'r', cb => sub { IO::AIO::poll_cb }); 31 my $w = AnyEvent->io (fh => $fh, poll => 'r', cb => sub { IO::AIO::poll_cb });
32
33 # EV integration
34 my $w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
32 35
33 # Event integration 36 # Event integration
34 Event->io (fd => IO::AIO::poll_fileno, 37 Event->io (fd => IO::AIO::poll_fileno,
35 poll => 'r', 38 poll => 'r',
36 cb => \&IO::AIO::poll_cb); 39 cb => \&IO::AIO::poll_cb);
260 263
261 aio_close $fh, $callback->($status) 264 aio_close $fh, $callback->($status)
262 Asynchronously close a file and call the callback with the result 265 Asynchronously close a file and call the callback with the result
263 code. 266 code.
264 267
265 Unlike the other functions operating on files, this function uses 268 Unfortunately, you can't do this to perl. Perl *insists* very
266 the PerlIO layer to close the filehandle. The reason is that the 269 strongly on closing the file descriptor associated with the
267 PerlIO API insists on closing the underlying fd itself, no matter 270 filehandle itself.
268 what, and doesn't allow modifications to the fd. Unfortunately, it
269 is not clear that you can call PerlIO from different threads
270 (actually, its quite clear that this won't work in some cases), so
271 while it likely works perfectly with simple file handles (such as
272 the ones created by "aio_open") it might fail in interesting ways
273 for others.
274 271
275 Having said that, aio_close tries to clean up the filehandle as much 272 Therefore, "aio_close" will not close the filehandle - instead it
276 as possible before handing it to an io thread, and generally does 273 will use dup2 to overwrite the file descriptor with the write-end of
277 work. 274 a pipe (the pipe fd will be created on demand and will be cached).
275
276 Or in other words: the file descriptor will be closed, but it will
277 not be free for reuse until the perl filehandle is closed.
278 278
279 aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) 279 aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
280 aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) 280 aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
281 Reads or writes $length bytes from the specified $fh and $offset 281 Reads or writes $length bytes from the specified $fh and $offset
282 into the scalar given by $data and offset $dataoffset and calls the 282 into the scalar given by $data and offset $dataoffset and calls the
529 Delete a directory tree starting (and including) $path, return the 529 Delete a directory tree starting (and including) $path, return the
530 status of the final "rmdir" only. This is a composite request that 530 status of the final "rmdir" only. This is a composite request that
531 uses "aio_scandir" to recurse into and rmdir directories, and unlink 531 uses "aio_scandir" to recurse into and rmdir directories, and unlink
532 everything else. 532 everything else.
533 533
534 aio_sync $callback->($status)
535 Asynchronously call sync and call the callback when finished.
536
534 aio_fsync $fh, $callback->($status) 537 aio_fsync $fh, $callback->($status)
535 Asynchronously call fsync on the given filehandle and call the 538 Asynchronously call fsync on the given filehandle and call the
536 callback with the fsync result code. 539 callback with the fsync result code.
537 540
538 aio_fdatasync $fh, $callback->($status) 541 aio_fdatasync $fh, $callback->($status)
539 Asynchronously call fdatasync on the given filehandle and call the 542 Asynchronously call fdatasync on the given filehandle and call the
540 callback with the fdatasync result code. 543 callback with the fdatasync result code.
541 544
542 If this call isn't available because your OS lacks it or it couldn't 545 If this call isn't available because your OS lacks it or it couldn't
543 be detected, it will be emulated by calling "fsync" instead. 546 be detected, it will be emulated by calling "fsync" instead.
547
548 aio_pathsync $path, $callback->($status)
549 This request tries to open, fsync and close the given path. This is
550 a composite request intended tosync directories after directory
551 operations (E.g. rename). This might not work on all operating
552 systems or have any specific effect, but usually it makes sure that
553 directory changes get written to disc. It works for anything that
554 can be opened for read-only, not just directories.
555
556 Passes 0 when everything went ok, and -1 on error.
544 557
545 aio_group $callback->(...) 558 aio_group $callback->(...)
546 This is a very special aio request: Instead of doing something, it 559 This is a very special aio request: Instead of doing something, it
547 is a container for other aio requests, which is useful if you want 560 is a container for other aio requests, which is useful if you want
548 to bundle many requests into a single, composite, request with a 561 to bundle many requests into a single, composite, request with a
630 }; 643 };
631 644
632 This makes it very easy to create composite requests (see the source of 645 This makes it very easy to create composite requests (see the source of
633 "aio_move" for an application) that work and feel like simple requests. 646 "aio_move" for an application) that work and feel like simple requests.
634 647
635 * The IO::AIO::GRP objects will be cleaned up during calls to 648 * The IO::AIO::GRP objects will be cleaned up during calls to
636 "IO::AIO::poll_cb", just like any other request. 649 "IO::AIO::poll_cb", just like any other request.
650
637 * They can be canceled like any other request. Canceling will cancel not 651 * They can be canceled like any other request. Canceling will cancel
638 only the request itself, but also all requests it contains. 652 not only the request itself, but also all requests it contains.
653
639 * They can also can also be added to other IO::AIO::GRP objects. 654 * They can also can also be added to other IO::AIO::GRP objects.
655
640 * You must not add requests to a group from within the group callback 656 * You must not add requests to a group from within the group callback
641 (or any later time). 657 (or any later time).
642 658
643 Their lifetime, simplified, looks like this: when they are empty, they 659 Their lifetime, simplified, looks like this: when they are empty, they
644 will finish very quickly. If they contain only requests that are in the 660 will finish very quickly. If they contain only requests that are in the
645 "done" state, they will also finish. Otherwise they will continue to 661 "done" state, they will also finish. Otherwise they will continue to
646 exist. 662 exist.
663 request itself. Useful when you queued a lot of events but got a 679 request itself. Useful when you queued a lot of events but got a
664 result early. 680 result early.
665 681
666 $grp->result (...) 682 $grp->result (...)
667 Set the result value(s) that will be passed to the group callback 683 Set the result value(s) that will be passed to the group callback
668 when all subrequests have finished and set thre groups errno to the 684 when all subrequests have finished and set the groups errno to the
669 current value of errno (just like calling "errno" without an error 685 current value of errno (just like calling "errno" without an error
670 number). By default, no argument will be passed and errno is zero. 686 number). By default, no argument will be passed and errno is zero.
671 687
672 $grp->errno ([$errno]) 688 $grp->errno ([$errno])
673 Sets the group errno value to $errno, or the current value of errno 689 Sets the group errno value to $errno, or the current value of errno

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