… | |
… | |
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); |
… | |
… | |
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 | Unfortunately, you can't do this to perl. Perl *insists* very |
268 | Unfortunately, you can't do this to perl. Perl *insists* very |
266 | strongly on closing the file descriptor associated with the |
269 | strongly on closing the file descriptor associated with the |
267 | filehandle itself. Here is what aio_close will try: |
270 | filehandle itself. |
268 | |
271 | |
269 | 1. dup()licate the fd |
272 | Therefore, "aio_close" will not close the filehandle - instead it |
270 | 2. asynchronously close() the duplicated fd |
273 | will use dup2 to overwrite the file descriptor with the write-end of |
271 | 3. dup()licate the fd once more |
274 | a pipe (the pipe fd will be created on demand and will be cached). |
272 | 4. let perl close() the filehandle |
|
|
273 | 5. asynchronously close the duplicated fd |
|
|
274 | |
275 | |
275 | The idea is that the first close() flushes stuff to disk that |
276 | Or in other words: the file descriptor will be closed, but it will |
276 | closing an fd will flush, so when perl closes the fd, nothing much |
277 | not be free for reuse until the perl filehandle is closed. |
277 | will need to be flushed. The second async. close() will then flush |
|
|
278 | stuff to disk that closing the last fd to the file will flush. |
|
|
279 | |
|
|
280 | Just FYI, SuSv3 has this to say on close: |
|
|
281 | |
|
|
282 | All outstanding record locks owned by the process on the file |
|
|
283 | associated with the file descriptor shall be removed. |
|
|
284 | |
|
|
285 | If fildes refers to a socket, close() shall cause the socket to be |
|
|
286 | destroyed. ... close() shall block for up to the current linger |
|
|
287 | interval until all data is transmitted. |
|
|
288 | [this actually sounds like a specification bug, but who knows] |
|
|
289 | |
|
|
290 | And at least Linux additionally actually flushes stuff on every |
|
|
291 | close, even when the file itself is still open. |
|
|
292 | |
|
|
293 | Sounds enourmously inefficient and complicated? Yes... please show |
|
|
294 | me how to nuke perl's fd out of existence... |
|
|
295 | |
278 | |
296 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
279 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
297 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
280 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
298 | Reads or writes $length bytes from the specified $fh and $offset |
281 | Reads or writes $length bytes from the specified $fh and $offset |
299 | 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 |
… | |
… | |
546 | Delete a directory tree starting (and including) $path, return the |
529 | Delete a directory tree starting (and including) $path, return the |
547 | 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 |
548 | uses "aio_scandir" to recurse into and rmdir directories, and unlink |
531 | uses "aio_scandir" to recurse into and rmdir directories, and unlink |
549 | everything else. |
532 | everything else. |
550 | |
533 | |
|
|
534 | aio_sync $callback->($status) |
|
|
535 | Asynchronously call sync and call the callback when finished. |
|
|
536 | |
551 | aio_fsync $fh, $callback->($status) |
537 | aio_fsync $fh, $callback->($status) |
552 | Asynchronously call fsync on the given filehandle and call the |
538 | Asynchronously call fsync on the given filehandle and call the |
553 | callback with the fsync result code. |
539 | callback with the fsync result code. |
554 | |
540 | |
555 | aio_fdatasync $fh, $callback->($status) |
541 | aio_fdatasync $fh, $callback->($status) |
556 | Asynchronously call fdatasync on the given filehandle and call the |
542 | Asynchronously call fdatasync on the given filehandle and call the |
557 | callback with the fdatasync result code. |
543 | callback with the fdatasync result code. |
558 | |
544 | |
559 | 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 |
560 | 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. |
561 | |
557 | |
562 | aio_group $callback->(...) |
558 | aio_group $callback->(...) |
563 | 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 |
564 | 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 |
565 | to bundle many requests into a single, composite, request with a |
561 | to bundle many requests into a single, composite, request with a |
… | |
… | |
647 | }; |
643 | }; |
648 | |
644 | |
649 | 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 |
650 | "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. |
651 | |
647 | |
652 | * 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 |
653 | "IO::AIO::poll_cb", just like any other request. |
649 | "IO::AIO::poll_cb", just like any other request. |
|
|
650 | |
654 | * They can be canceled like any other request. Canceling will cancel not |
651 | * They can be canceled like any other request. Canceling will cancel |
655 | only the request itself, but also all requests it contains. |
652 | not only the request itself, but also all requests it contains. |
|
|
653 | |
656 | * 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 | |
657 | * 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 |
658 | (or any later time). |
657 | (or any later time). |
659 | |
658 | |
660 | Their lifetime, simplified, looks like this: when they are empty, they |
659 | Their lifetime, simplified, looks like this: when they are empty, they |
661 | 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 |
662 | "done" state, they will also finish. Otherwise they will continue to |
661 | "done" state, they will also finish. Otherwise they will continue to |
663 | exist. |
662 | exist. |
… | |
… | |
680 | 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 |
681 | result early. |
680 | result early. |
682 | |
681 | |
683 | $grp->result (...) |
682 | $grp->result (...) |
684 | 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 |
685 | 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 |
686 | current value of errno (just like calling "errno" without an error |
685 | current value of errno (just like calling "errno" without an error |
687 | 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. |
688 | |
687 | |
689 | $grp->errno ([$errno]) |
688 | $grp->errno ([$errno]) |
690 | 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 |