| 1 | =head1 NAME |
1 | =head1 NAME |
| 2 | |
2 | |
| 3 | IO::AIO - Asynchronous Input/Output |
3 | IO::AIO - Asynchronous/Advanced Input/Output |
| 4 | |
4 | |
| 5 | =head1 SYNOPSIS |
5 | =head1 SYNOPSIS |
| 6 | |
6 | |
| 7 | use IO::AIO; |
7 | use IO::AIO; |
| 8 | |
8 | |
| … | |
… | |
| 58 | not well-supported or restricted (GNU/Linux doesn't allow them on normal |
58 | not well-supported or restricted (GNU/Linux doesn't allow them on normal |
| 59 | files currently, for example), and they would only support aio_read and |
59 | files currently, for example), and they would only support aio_read and |
| 60 | aio_write, so the remaining functionality would have to be implemented |
60 | aio_write, so the remaining functionality would have to be implemented |
| 61 | using threads anyway. |
61 | using threads anyway. |
| 62 | |
62 | |
|
|
63 | In addition to asynchronous I/O, this module also exports some rather |
|
|
64 | arcane interfaces, such as C<madvise> or linux's C<splice> system call, |
|
|
65 | which is why the C<A> in C<AIO> can also mean I<advanced>. |
|
|
66 | |
| 63 | Although the module will work in the presence of other (Perl-) threads, |
67 | Although the module will work in the presence of other (Perl-) threads, |
| 64 | it is currently not reentrant in any way, so use appropriate locking |
68 | it is currently not reentrant in any way, so use appropriate locking |
| 65 | yourself, always call C<poll_cb> from within the same thread, or never |
69 | yourself, always call C<poll_cb> from within the same thread, or never |
| 66 | call C<poll_cb> (or other C<aio_> functions) recursively. |
70 | call C<poll_cb> (or other C<aio_> functions) recursively. |
| 67 | |
71 | |
| 68 | =head2 EXAMPLE |
72 | =head2 EXAMPLE |
| 69 | |
73 | |
| 70 | This is a simple example that uses the EV module and loads |
74 | This is a simple example that uses the EV module and loads |
| 71 | F</etc/passwd> asynchronously: |
75 | F</etc/passwd> asynchronously: |
| 72 | |
76 | |
| 73 | use Fcntl; |
|
|
| 74 | use EV; |
77 | use EV; |
| 75 | use IO::AIO; |
78 | use IO::AIO; |
| 76 | |
79 | |
| 77 | # register the IO::AIO callback with EV |
80 | # register the IO::AIO callback with EV |
| 78 | my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb; |
81 | my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb; |
| … | |
… | |
| 95 | |
98 | |
| 96 | # file contents now in $contents |
99 | # file contents now in $contents |
| 97 | print $contents; |
100 | print $contents; |
| 98 | |
101 | |
| 99 | # exit event loop and program |
102 | # exit event loop and program |
| 100 | EV::unloop; |
103 | EV::break; |
| 101 | }; |
104 | }; |
| 102 | }; |
105 | }; |
| 103 | |
106 | |
| 104 | # possibly queue up other requests, or open GUI windows, |
107 | # possibly queue up other requests, or open GUI windows, |
| 105 | # check for sockets etc. etc. |
108 | # check for sockets etc. etc. |
| 106 | |
109 | |
| 107 | # process events as long as there are some: |
110 | # process events as long as there are some: |
| 108 | EV::loop; |
111 | EV::run; |
| 109 | |
112 | |
| 110 | =head1 REQUEST ANATOMY AND LIFETIME |
113 | =head1 REQUEST ANATOMY AND LIFETIME |
| 111 | |
114 | |
| 112 | Every C<aio_*> function creates a request. which is a C data structure not |
115 | Every C<aio_*> function creates a request. which is a C data structure not |
| 113 | directly visible to Perl. |
116 | directly visible to Perl. |
| … | |
… | |
| 168 | use common::sense; |
171 | use common::sense; |
| 169 | |
172 | |
| 170 | use base 'Exporter'; |
173 | use base 'Exporter'; |
| 171 | |
174 | |
| 172 | BEGIN { |
175 | BEGIN { |
| 173 | our $VERSION = '4.16'; |
176 | our $VERSION = 4.35; |
| 174 | |
177 | |
| 175 | our @AIO_REQ = qw(aio_sendfile aio_seek aio_read aio_write aio_open aio_close |
178 | our @AIO_REQ = qw(aio_sendfile aio_seek aio_read aio_write aio_open aio_close |
| 176 | aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx |
179 | aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx |
| 177 | aio_scandir aio_symlink aio_readlink aio_realpath aio_sync |
180 | aio_scandir aio_symlink aio_readlink aio_realpath aio_fcntl aio_ioctl |
| 178 | aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range aio_allocate |
181 | aio_sync aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range |
| 179 | aio_pathsync aio_readahead aio_fiemap |
182 | aio_pathsync aio_readahead aio_fiemap aio_allocate |
| 180 | aio_rename aio_link aio_move aio_copy aio_group |
183 | aio_rename aio_rename2 aio_link aio_move aio_copy aio_group |
| 181 | aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown |
184 | aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown |
| 182 | aio_chmod aio_utime aio_truncate |
185 | aio_chmod aio_utime aio_truncate |
| 183 | aio_msync aio_mtouch aio_mlock aio_mlockall |
186 | aio_msync aio_mtouch aio_mlock aio_mlockall |
| 184 | aio_statvfs |
187 | aio_statvfs |
| 185 | aio_wd); |
188 | aio_wd); |
| … | |
… | |
| 228 | aio_unlink $pathname, $callback->($status) |
231 | aio_unlink $pathname, $callback->($status) |
| 229 | aio_mknod $pathname, $mode, $dev, $callback->($status) |
232 | aio_mknod $pathname, $mode, $dev, $callback->($status) |
| 230 | aio_link $srcpath, $dstpath, $callback->($status) |
233 | aio_link $srcpath, $dstpath, $callback->($status) |
| 231 | aio_symlink $srcpath, $dstpath, $callback->($status) |
234 | aio_symlink $srcpath, $dstpath, $callback->($status) |
| 232 | aio_readlink $pathname, $callback->($link) |
235 | aio_readlink $pathname, $callback->($link) |
| 233 | aio_realpath $pathname, $callback->($link) |
236 | aio_realpath $pathname, $callback->($path) |
| 234 | aio_rename $srcpath, $dstpath, $callback->($status) |
237 | aio_rename $srcpath, $dstpath, $callback->($status) |
|
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238 | aio_rename2 $srcpath, $dstpath, $flags, $callback->($status) |
| 235 | aio_mkdir $pathname, $mode, $callback->($status) |
239 | aio_mkdir $pathname, $mode, $callback->($status) |
| 236 | aio_rmdir $pathname, $callback->($status) |
240 | aio_rmdir $pathname, $callback->($status) |
| 237 | aio_readdir $pathname, $callback->($entries) |
241 | aio_readdir $pathname, $callback->($entries) |
| 238 | aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
242 | aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
| 239 | IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST |
243 | IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST |
| … | |
… | |
| 241 | aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs) |
245 | aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs) |
| 242 | aio_load $pathname, $data, $callback->($status) |
246 | aio_load $pathname, $data, $callback->($status) |
| 243 | aio_copy $srcpath, $dstpath, $callback->($status) |
247 | aio_copy $srcpath, $dstpath, $callback->($status) |
| 244 | aio_move $srcpath, $dstpath, $callback->($status) |
248 | aio_move $srcpath, $dstpath, $callback->($status) |
| 245 | aio_rmtree $pathname, $callback->($status) |
249 | aio_rmtree $pathname, $callback->($status) |
|
|
250 | aio_fcntl $fh, $cmd, $arg, $callback->($status) |
|
|
251 | aio_ioctl $fh, $request, $buf, $callback->($status) |
| 246 | aio_sync $callback->($status) |
252 | aio_sync $callback->($status) |
| 247 | aio_syncfs $fh, $callback->($status) |
253 | aio_syncfs $fh, $callback->($status) |
| 248 | aio_fsync $fh, $callback->($status) |
254 | aio_fsync $fh, $callback->($status) |
| 249 | aio_fdatasync $fh, $callback->($status) |
255 | aio_fdatasync $fh, $callback->($status) |
| 250 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
256 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
| 251 | aio_pathsync $pathname, $callback->($status) |
257 | aio_pathsync $pathname, $callback->($status) |
| 252 | aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
258 | aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status) |
| 253 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
259 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
| 254 | aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
260 | aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
| 255 | aio_mlockall $flags, $callback->($status) |
261 | aio_mlockall $flags, $callback->($status) |
| 256 | aio_group $callback->(...) |
262 | aio_group $callback->(...) |
| 257 | aio_nop $callback->() |
263 | aio_nop $callback->() |
| … | |
… | |
| 271 | IO::AIO::idle_timeout $seconds |
277 | IO::AIO::idle_timeout $seconds |
| 272 | IO::AIO::max_outstanding $maxreqs |
278 | IO::AIO::max_outstanding $maxreqs |
| 273 | IO::AIO::nreqs |
279 | IO::AIO::nreqs |
| 274 | IO::AIO::nready |
280 | IO::AIO::nready |
| 275 | IO::AIO::npending |
281 | IO::AIO::npending |
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|
282 | $nfd = IO::AIO::get_fdlimit [EXPERIMENTAL] |
|
|
283 | IO::AIO::min_fdlimit $nfd [EXPERIMENTAL] |
| 276 | |
284 | |
| 277 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
285 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
| 278 | IO::AIO::fadvise $fh, $offset, $len, $advice |
286 | IO::AIO::fadvise $fh, $offset, $len, $advice |
| 279 | IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]] |
287 | IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]] |
| 280 | IO::AIO::munmap $scalar |
288 | IO::AIO::munmap $scalar |
| … | |
… | |
| 395 | following POSIX and non-POSIX constants are available (missing ones on |
403 | following POSIX and non-POSIX constants are available (missing ones on |
| 396 | your system are, as usual, C<0>): |
404 | your system are, as usual, C<0>): |
| 397 | |
405 | |
| 398 | C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>, |
406 | C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>, |
| 399 | C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>, |
407 | C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>, |
| 400 | C<O_RSYNC>, C<O_SYNC> and C<O_TTY_INIT>. |
408 | C<O_RSYNC>, C<O_SYNC>, C<O_PATH>, C<O_TMPFILE>, and C<O_TTY_INIT>. |
| 401 | |
409 | |
| 402 | |
410 | |
| 403 | =item aio_close $fh, $callback->($status) |
411 | =item aio_close $fh, $callback->($status) |
| 404 | |
412 | |
| 405 | Asynchronously close a file and call the callback with the result |
413 | Asynchronously close a file and call the callback with the result |
| … | |
… | |
| 440 | =item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
448 | =item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
| 441 | |
449 | |
| 442 | =item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
450 | =item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
| 443 | |
451 | |
| 444 | Reads or writes C<$length> bytes from or to the specified C<$fh> and |
452 | Reads or writes C<$length> bytes from or to the specified C<$fh> and |
| 445 | C<$offset> into the scalar given by C<$data> and offset C<$dataoffset> |
453 | C<$offset> into the scalar given by C<$data> and offset C<$dataoffset> and |
| 446 | and calls the callback without the actual number of bytes read (or -1 on |
454 | calls the callback with the actual number of bytes transferred (or -1 on |
| 447 | error, just like the syscall). |
455 | error, just like the syscall). |
| 448 | |
456 | |
| 449 | C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to |
457 | C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to |
| 450 | offset plus the actual number of bytes read. |
458 | offset plus the actual number of bytes read. |
| 451 | |
459 | |
| … | |
… | |
| 509 | As native sendfile syscalls (as practically any non-POSIX interface hacked |
517 | As native sendfile syscalls (as practically any non-POSIX interface hacked |
| 510 | together in a hurry to improve benchmark numbers) tend to be rather buggy |
518 | together in a hurry to improve benchmark numbers) tend to be rather buggy |
| 511 | on many systems, this implementation tries to work around some known bugs |
519 | on many systems, this implementation tries to work around some known bugs |
| 512 | in Linux and FreeBSD kernels (probably others, too), but that might fail, |
520 | in Linux and FreeBSD kernels (probably others, too), but that might fail, |
| 513 | so you really really should check the return value of C<aio_sendfile> - |
521 | so you really really should check the return value of C<aio_sendfile> - |
| 514 | fewre bytes than expected might have been transferred. |
522 | fewer bytes than expected might have been transferred. |
| 515 | |
523 | |
| 516 | |
524 | |
| 517 | =item aio_readahead $fh,$offset,$length, $callback->($retval) |
525 | =item aio_readahead $fh,$offset,$length, $callback->($retval) |
| 518 | |
526 | |
| 519 | C<aio_readahead> populates the page cache with data from a file so that |
527 | C<aio_readahead> populates the page cache with data from a file so that |
| … | |
… | |
| 523 | whole pages, so that offset is effectively rounded down to a page boundary |
531 | whole pages, so that offset is effectively rounded down to a page boundary |
| 524 | and bytes are read up to the next page boundary greater than or equal to |
532 | and bytes are read up to the next page boundary greater than or equal to |
| 525 | (off-set+length). C<aio_readahead> does not read beyond the end of the |
533 | (off-set+length). C<aio_readahead> does not read beyond the end of the |
| 526 | file. The current file offset of the file is left unchanged. |
534 | file. The current file offset of the file is left unchanged. |
| 527 | |
535 | |
| 528 | If that syscall doesn't exist (likely if your OS isn't Linux) it will be |
536 | If that syscall doesn't exist (likely if your kernel isn't Linux) it will |
| 529 | emulated by simply reading the data, which would have a similar effect. |
537 | be emulated by simply reading the data, which would have a similar effect. |
| 530 | |
538 | |
| 531 | |
539 | |
| 532 | =item aio_stat $fh_or_path, $callback->($status) |
540 | =item aio_stat $fh_or_path, $callback->($status) |
| 533 | |
541 | |
| 534 | =item aio_lstat $fh, $callback->($status) |
542 | =item aio_lstat $fh, $callback->($status) |
| … | |
… | |
| 603 | namemax => 255, |
611 | namemax => 255, |
| 604 | frsize => 1024, |
612 | frsize => 1024, |
| 605 | fsid => 1810 |
613 | fsid => 1810 |
| 606 | } |
614 | } |
| 607 | |
615 | |
| 608 | Here is a (likely partial) list of fsid values used by Linux - it is safe |
616 | Here is a (likely partial - send me updates!) list of fsid values used by |
| 609 | to hardcode these when the $^O is C<linux>: |
617 | Linux - it is safe to hardcode these when C<$^O> is C<linux>: |
| 610 | |
618 | |
| 611 | 0x0000adf5 adfs |
619 | 0x0000adf5 adfs |
| 612 | 0x0000adff affs |
620 | 0x0000adff affs |
| 613 | 0x5346414f afs |
621 | 0x5346414f afs |
| 614 | 0x09041934 anon-inode filesystem |
622 | 0x09041934 anon-inode filesystem |
| … | |
… | |
| 627 | 0x00001373 devfs |
635 | 0x00001373 devfs |
| 628 | 0x00001cd1 devpts |
636 | 0x00001cd1 devpts |
| 629 | 0x0000f15f ecryptfs |
637 | 0x0000f15f ecryptfs |
| 630 | 0x00414a53 efs |
638 | 0x00414a53 efs |
| 631 | 0x0000137d ext |
639 | 0x0000137d ext |
| 632 | 0x0000ef53 ext2/ext3 |
640 | 0x0000ef53 ext2/ext3/ext4 |
| 633 | 0x0000ef51 ext2 |
641 | 0x0000ef51 ext2 |
|
|
642 | 0xf2f52010 f2fs |
| 634 | 0x00004006 fat |
643 | 0x00004006 fat |
| 635 | 0x65735546 fuseblk |
644 | 0x65735546 fuseblk |
| 636 | 0x65735543 fusectl |
645 | 0x65735543 fusectl |
| 637 | 0x0bad1dea futexfs |
646 | 0x0bad1dea futexfs |
| 638 | 0x01161970 gfs2 |
647 | 0x01161970 gfs2 |
| 639 | 0x47504653 gpfs |
648 | 0x47504653 gpfs |
| 640 | 0x00004244 hfs |
649 | 0x00004244 hfs |
| 641 | 0xf995e849 hpfs |
650 | 0xf995e849 hpfs |
|
|
651 | 0x00c0ffee hostfs |
| 642 | 0x958458f6 hugetlbfs |
652 | 0x958458f6 hugetlbfs |
| 643 | 0x2bad1dea inotifyfs |
653 | 0x2bad1dea inotifyfs |
| 644 | 0x00009660 isofs |
654 | 0x00009660 isofs |
| 645 | 0x000072b6 jffs2 |
655 | 0x000072b6 jffs2 |
| 646 | 0x3153464a jfs |
656 | 0x3153464a jfs |
| … | |
… | |
| 661 | 0x00009fa1 openprom |
671 | 0x00009fa1 openprom |
| 662 | 0x7461636F ocfs2 |
672 | 0x7461636F ocfs2 |
| 663 | 0x00009fa0 proc |
673 | 0x00009fa0 proc |
| 664 | 0x6165676c pstorefs |
674 | 0x6165676c pstorefs |
| 665 | 0x0000002f qnx4 |
675 | 0x0000002f qnx4 |
|
|
676 | 0x68191122 qnx6 |
| 666 | 0x858458f6 ramfs |
677 | 0x858458f6 ramfs |
| 667 | 0x52654973 reiserfs |
678 | 0x52654973 reiserfs |
| 668 | 0x00007275 romfs |
679 | 0x00007275 romfs |
| 669 | 0x67596969 rpc_pipefs |
680 | 0x67596969 rpc_pipefs |
| 670 | 0x73636673 securityfs |
681 | 0x73636673 securityfs |
| … | |
… | |
| 723 | Works like truncate(2) or ftruncate(2). |
734 | Works like truncate(2) or ftruncate(2). |
| 724 | |
735 | |
| 725 | |
736 | |
| 726 | =item aio_allocate $fh, $mode, $offset, $len, $callback->($status) |
737 | =item aio_allocate $fh, $mode, $offset, $len, $callback->($status) |
| 727 | |
738 | |
| 728 | Allocates or freed disk space according to the C<$mode> argument. See the |
739 | Allocates or frees disk space according to the C<$mode> argument. See the |
| 729 | linux C<fallocate> docuemntation for details. |
740 | linux C<fallocate> documentation for details. |
| 730 | |
741 | |
| 731 | C<$mode> can currently be C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> |
742 | C<$mode> is usually C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> to allocate |
| 732 | to allocate space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE | |
743 | space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE | IO::AIO::FALLOC_FL_KEEP_SIZE>, |
| 733 | IO::AIO::FALLOC_FL_KEEP_SIZE>, to deallocate a file range. |
744 | to deallocate a file range. |
|
|
745 | |
|
|
746 | IO::AIO also supports C<FALLOC_FL_COLLAPSE_RANGE>, to remove a range |
|
|
747 | (without leaving a hole), C<FALLOC_FL_ZERO_RANGE>, to zero a range, |
|
|
748 | C<FALLOC_FL_INSERT_RANGE> to insert a range and C<FALLOC_FL_UNSHARE_RANGE> |
|
|
749 | to unshare shared blocks (see your L<fallocate(2)> manpage). |
| 734 | |
750 | |
| 735 | The file system block size used by C<fallocate> is presumably the |
751 | The file system block size used by C<fallocate> is presumably the |
| 736 | C<f_bsize> returned by C<statvfs>. |
752 | C<f_bsize> returned by C<statvfs>, but different filesystems and filetypes |
|
|
753 | can dictate other limitations. |
| 737 | |
754 | |
| 738 | If C<fallocate> isn't available or cannot be emulated (currently no |
755 | If C<fallocate> isn't available or cannot be emulated (currently no |
| 739 | emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>. |
756 | emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>. |
| 740 | |
757 | |
| 741 | |
758 | |
| … | |
… | |
| 783 | |
800 | |
| 784 | |
801 | |
| 785 | =item aio_realpath $pathname, $callback->($path) |
802 | =item aio_realpath $pathname, $callback->($path) |
| 786 | |
803 | |
| 787 | Asynchronously make the path absolute and resolve any symlinks in |
804 | Asynchronously make the path absolute and resolve any symlinks in |
| 788 | C<$path>. The resulting path only consists of directories (Same as |
805 | C<$path>. The resulting path only consists of directories (same as |
| 789 | L<Cwd::realpath>). |
806 | L<Cwd::realpath>). |
| 790 | |
807 | |
| 791 | This request can be used to get the absolute path of the current working |
808 | This request can be used to get the absolute path of the current working |
| 792 | directory by passing it a path of F<.> (a single dot). |
809 | directory by passing it a path of F<.> (a single dot). |
| 793 | |
810 | |
| 794 | |
811 | |
| 795 | =item aio_rename $srcpath, $dstpath, $callback->($status) |
812 | =item aio_rename $srcpath, $dstpath, $callback->($status) |
| 796 | |
813 | |
| 797 | Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as |
814 | Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as |
| 798 | rename(2) and call the callback with the result code. |
815 | rename(2) and call the callback with the result code. |
|
|
816 | |
|
|
817 | On systems that support the AIO::WD working directory abstraction |
|
|
818 | natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead |
|
|
819 | of failing, C<rename> is called on the absolute path of C<$wd>. |
|
|
820 | |
|
|
821 | |
|
|
822 | =item aio_rename2 $srcpath, $dstpath, $flags, $callback->($status) |
|
|
823 | |
|
|
824 | Basically a version of C<aio_rename> with an additional C<$flags> |
|
|
825 | argument. Calling this with C<$flags=0> is the same as calling |
|
|
826 | C<aio_rename>. |
|
|
827 | |
|
|
828 | Non-zero flags are currently only supported on GNU/Linux systems that |
|
|
829 | support renameat2. Other systems fail with C<ENOSYS> in this case. |
|
|
830 | |
|
|
831 | The following constants are available (missing ones are, as usual C<0>), |
|
|
832 | see renameat2(2) for details: |
|
|
833 | |
|
|
834 | C<IO::AIO::RENAME_NOREPLACE>, C<IO::AIO::RENAME_EXCHANGE> |
|
|
835 | and C<IO::AIO::RENAME_WHITEOUT>. |
| 799 | |
836 | |
| 800 | |
837 | |
| 801 | =item aio_mkdir $pathname, $mode, $callback->($status) |
838 | =item aio_mkdir $pathname, $mode, $callback->($status) |
| 802 | |
839 | |
| 803 | Asynchronously mkdir (create) a directory and call the callback with |
840 | Asynchronously mkdir (create) a directory and call the callback with |
| … | |
… | |
| 807 | |
844 | |
| 808 | =item aio_rmdir $pathname, $callback->($status) |
845 | =item aio_rmdir $pathname, $callback->($status) |
| 809 | |
846 | |
| 810 | Asynchronously rmdir (delete) a directory and call the callback with the |
847 | Asynchronously rmdir (delete) a directory and call the callback with the |
| 811 | result code. |
848 | result code. |
|
|
849 | |
|
|
850 | On systems that support the AIO::WD working directory abstraction |
|
|
851 | natively, the case C<[$wd, "."]> is specialcased - instead of failing, |
|
|
852 | C<rmdir> is called on the absolute path of C<$wd>. |
| 812 | |
853 | |
| 813 | |
854 | |
| 814 | =item aio_readdir $pathname, $callback->($entries) |
855 | =item aio_readdir $pathname, $callback->($entries) |
| 815 | |
856 | |
| 816 | Unlike the POSIX call of the same name, C<aio_readdir> reads an entire |
857 | Unlike the POSIX call of the same name, C<aio_readdir> reads an entire |
| … | |
… | |
| 918 | =item aio_copy $srcpath, $dstpath, $callback->($status) |
959 | =item aio_copy $srcpath, $dstpath, $callback->($status) |
| 919 | |
960 | |
| 920 | Try to copy the I<file> (directories not supported as either source or |
961 | Try to copy the I<file> (directories not supported as either source or |
| 921 | destination) from C<$srcpath> to C<$dstpath> and call the callback with |
962 | destination) from C<$srcpath> to C<$dstpath> and call the callback with |
| 922 | a status of C<0> (ok) or C<-1> (error, see C<$!>). |
963 | a status of C<0> (ok) or C<-1> (error, see C<$!>). |
|
|
964 | |
|
|
965 | Existing destination files will be truncated. |
| 923 | |
966 | |
| 924 | This is a composite request that creates the destination file with |
967 | This is a composite request that creates the destination file with |
| 925 | mode 0200 and copies the contents of the source file into it using |
968 | mode 0200 and copies the contents of the source file into it using |
| 926 | C<aio_sendfile>, followed by restoring atime, mtime, access mode and |
969 | C<aio_sendfile>, followed by restoring atime, mtime, access mode and |
| 927 | uid/gid, in that order. |
970 | uid/gid, in that order. |
| … | |
… | |
| 1037 | Scans a directory (similar to C<aio_readdir>) but additionally tries to |
1080 | Scans a directory (similar to C<aio_readdir>) but additionally tries to |
| 1038 | efficiently separate the entries of directory C<$path> into two sets of |
1081 | efficiently separate the entries of directory C<$path> into two sets of |
| 1039 | names, directories you can recurse into (directories), and ones you cannot |
1082 | names, directories you can recurse into (directories), and ones you cannot |
| 1040 | recurse into (everything else, including symlinks to directories). |
1083 | recurse into (everything else, including symlinks to directories). |
| 1041 | |
1084 | |
| 1042 | C<aio_scandir> is a composite request that creates of many sub requests_ |
1085 | C<aio_scandir> is a composite request that generates many sub requests. |
| 1043 | C<$maxreq> specifies the maximum number of outstanding aio requests that |
1086 | C<$maxreq> specifies the maximum number of outstanding aio requests that |
| 1044 | this function generates. If it is C<< <= 0 >>, then a suitable default |
1087 | this function generates. If it is C<< <= 0 >>, then a suitable default |
| 1045 | will be chosen (currently 4). |
1088 | will be chosen (currently 4). |
| 1046 | |
1089 | |
| 1047 | On error, the callback is called without arguments, otherwise it receives |
1090 | On error, the callback is called without arguments, otherwise it receives |
| … | |
… | |
| 1181 | } |
1224 | } |
| 1182 | |
1225 | |
| 1183 | =item aio_rmtree $pathname, $callback->($status) |
1226 | =item aio_rmtree $pathname, $callback->($status) |
| 1184 | |
1227 | |
| 1185 | Delete a directory tree starting (and including) C<$path>, return the |
1228 | Delete a directory tree starting (and including) C<$path>, return the |
| 1186 | status of the final C<rmdir> only. This is a composite request that |
1229 | status of the final C<rmdir> only. This is a composite request that |
| 1187 | uses C<aio_scandir> to recurse into and rmdir directories, and unlink |
1230 | uses C<aio_scandir> to recurse into and rmdir directories, and unlink |
| 1188 | everything else. |
1231 | everything else. |
| 1189 | |
1232 | |
| 1190 | =cut |
1233 | =cut |
| 1191 | |
1234 | |
| … | |
… | |
| 1212 | add $grp $dirgrp; |
1255 | add $grp $dirgrp; |
| 1213 | }; |
1256 | }; |
| 1214 | |
1257 | |
| 1215 | $grp |
1258 | $grp |
| 1216 | } |
1259 | } |
|
|
1260 | |
|
|
1261 | =item aio_fcntl $fh, $cmd, $arg, $callback->($status) |
|
|
1262 | |
|
|
1263 | =item aio_ioctl $fh, $request, $buf, $callback->($status) |
|
|
1264 | |
|
|
1265 | These work just like the C<fcntl> and C<ioctl> built-in functions, except |
|
|
1266 | they execute asynchronously and pass the return value to the callback. |
|
|
1267 | |
|
|
1268 | Both calls can be used for a lot of things, some of which make more sense |
|
|
1269 | to run asynchronously in their own thread, while some others make less |
|
|
1270 | sense. For example, calls that block waiting for external events, such |
|
|
1271 | as locking, will also lock down an I/O thread while it is waiting, which |
|
|
1272 | can deadlock the whole I/O system. At the same time, there might be no |
|
|
1273 | alternative to using a thread to wait. |
|
|
1274 | |
|
|
1275 | So in general, you should only use these calls for things that do |
|
|
1276 | (filesystem) I/O, not for things that wait for other events (network, |
|
|
1277 | other processes), although if you are careful and know what you are doing, |
|
|
1278 | you still can. |
|
|
1279 | |
|
|
1280 | The following constants are available (missing ones are, as usual C<0>): |
|
|
1281 | |
|
|
1282 | C<F_DUPFD_CLOEXEC>, |
|
|
1283 | |
|
|
1284 | C<F_OFD_GETLK>, C<F_OFD_SETLK>, C<F_OFD_GETLKW>, |
|
|
1285 | |
|
|
1286 | C<FIFREEZE>, C<FITHAW>, C<FITRIM>, C<FICLONE>, C<FICLONERANGE>, C<FIDEDUPERANGE>. |
|
|
1287 | |
|
|
1288 | C<FS_IOC_GETFLAGS>, C<FS_IOC_SETFLAGS>, C<FS_IOC_GETVERSION>, C<FS_IOC_SETVERSION>, |
|
|
1289 | C<FS_IOC_FIEMAP>. |
|
|
1290 | |
|
|
1291 | C<FS_IOC_FSGETXATTR>, C<FS_IOC_FSSETXATTR>, C<FS_IOC_SET_ENCRYPTION_POLICY>, |
|
|
1292 | C<FS_IOC_GET_ENCRYPTION_PWSALT>, C<FS_IOC_GET_ENCRYPTION_POLICY>, C<FS_KEY_DESCRIPTOR_SIZE>. |
|
|
1293 | |
|
|
1294 | C<FS_SECRM_FL>, C<FS_UNRM_FL>, C<FS_COMPR_FL>, C<FS_SYNC_FL>, C<FS_IMMUTABLE_FL>, |
|
|
1295 | C<FS_APPEND_FL>, C<FS_NODUMP_FL>, C<FS_NOATIME_FL>, C<FS_DIRTY_FL>, |
|
|
1296 | C<FS_COMPRBLK_FL>, C<FS_NOCOMP_FL>, C<FS_ENCRYPT_FL>, C<FS_BTREE_FL>, |
|
|
1297 | C<FS_INDEX_FL>, C<FS_JOURNAL_DATA_FL>, C<FS_NOTAIL_FL>, C<FS_DIRSYNC_FL>, C<FS_TOPDIR_FL>, |
|
|
1298 | C<FS_FL_USER_MODIFIABLE>. |
|
|
1299 | |
|
|
1300 | C<FS_XFLAG_REALTIME>, C<FS_XFLAG_PREALLOC>, C<FS_XFLAG_IMMUTABLE>, C<FS_XFLAG_APPEND>, |
|
|
1301 | C<FS_XFLAG_SYNC>, C<FS_XFLAG_NOATIME>, C<FS_XFLAG_NODUMP>, C<FS_XFLAG_RTINHERIT>, |
|
|
1302 | C<FS_XFLAG_PROJINHERIT>, C<FS_XFLAG_NOSYMLINKS>, C<FS_XFLAG_EXTSIZE>, C<FS_XFLAG_EXTSZINHERIT>, |
|
|
1303 | C<FS_XFLAG_NODEFRAG>, C<FS_XFLAG_FILESTREAM>, C<FS_XFLAG_DAX>, C<FS_XFLAG_HASATTR>, |
| 1217 | |
1304 | |
| 1218 | =item aio_sync $callback->($status) |
1305 | =item aio_sync $callback->($status) |
| 1219 | |
1306 | |
| 1220 | Asynchronously call sync and call the callback when finished. |
1307 | Asynchronously call sync and call the callback when finished. |
| 1221 | |
1308 | |
| … | |
… | |
| 1290 | }; |
1377 | }; |
| 1291 | |
1378 | |
| 1292 | $grp |
1379 | $grp |
| 1293 | } |
1380 | } |
| 1294 | |
1381 | |
| 1295 | =item aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
1382 | =item aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status) |
| 1296 | |
1383 | |
| 1297 | This is a rather advanced IO::AIO call, which only works on mmap(2)ed |
1384 | This is a rather advanced IO::AIO call, which only works on mmap(2)ed |
| 1298 | scalars (see the C<IO::AIO::mmap> function, although it also works on data |
1385 | scalars (see the C<IO::AIO::mmap> function, although it also works on data |
| 1299 | scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the |
1386 | scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the |
| 1300 | scalar must only be modified in-place while an aio operation is pending on |
1387 | scalar must only be modified in-place while an aio operation is pending on |
| … | |
… | |
| 1302 | |
1389 | |
| 1303 | It calls the C<msync> function of your OS, if available, with the memory |
1390 | It calls the C<msync> function of your OS, if available, with the memory |
| 1304 | area starting at C<$offset> in the string and ending C<$length> bytes |
1391 | area starting at C<$offset> in the string and ending C<$length> bytes |
| 1305 | later. If C<$length> is negative, counts from the end, and if C<$length> |
1392 | later. If C<$length> is negative, counts from the end, and if C<$length> |
| 1306 | is C<undef>, then it goes till the end of the string. The flags can be |
1393 | is C<undef>, then it goes till the end of the string. The flags can be |
| 1307 | a combination of C<IO::AIO::MS_ASYNC>, C<IO::AIO::MS_INVALIDATE> and |
1394 | either C<IO::AIO::MS_ASYNC> or C<IO::AIO::MS_SYNC>, plus an optional |
| 1308 | C<IO::AIO::MS_SYNC>. |
1395 | C<IO::AIO::MS_INVALIDATE>. |
| 1309 | |
1396 | |
| 1310 | =item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
1397 | =item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
| 1311 | |
1398 | |
| 1312 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
1399 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
| 1313 | scalars. |
1400 | scalars. |
| 1314 | |
1401 | |
| 1315 | It touches (reads or writes) all memory pages in the specified |
1402 | It touches (reads or writes) all memory pages in the specified |
| 1316 | range inside the scalar. All caveats and parameters are the same |
1403 | range inside the scalar. All caveats and parameters are the same |
| 1317 | as for C<aio_msync>, above, except for flags, which must be either |
1404 | as for C<aio_msync>, above, except for flags, which must be either |
| 1318 | C<0> (which reads all pages and ensures they are instantiated) or |
1405 | C<0> (which reads all pages and ensures they are instantiated) or |
| 1319 | C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and |
1406 | C<IO::AIO::MT_MODIFY>, which modifies the memory pages (by reading and |
| 1320 | writing an octet from it, which dirties the page). |
1407 | writing an octet from it, which dirties the page). |
| 1321 | |
1408 | |
| 1322 | =item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
1409 | =item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
| 1323 | |
1410 | |
| 1324 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
1411 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
| … | |
… | |
| 1396 | C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>, |
1483 | C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>, |
| 1397 | C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>, |
1484 | C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>, |
| 1398 | C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or |
1485 | C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or |
| 1399 | C<IO::AIO::FIEMAP_EXTENT_SHARED>. |
1486 | C<IO::AIO::FIEMAP_EXTENT_SHARED>. |
| 1400 | |
1487 | |
| 1401 | At the time of this writing (Linux 3.2), this requets is unreliable unless |
1488 | At the time of this writing (Linux 3.2), this request is unreliable unless |
| 1402 | C<$count> is C<undef>, as the kernel has all sorts of bugs preventing |
1489 | C<$count> is C<undef>, as the kernel has all sorts of bugs preventing |
| 1403 | it to return all extents of a range for files with large number of |
1490 | it to return all extents of a range for files with a large number of |
| 1404 | extents. The code works around all these issues if C<$count> is undef. |
1491 | extents. The code (only) works around all these issues if C<$count> is |
|
|
1492 | C<undef>. |
| 1405 | |
1493 | |
| 1406 | =item aio_group $callback->(...) |
1494 | =item aio_group $callback->(...) |
| 1407 | |
1495 | |
| 1408 | This is a very special aio request: Instead of doing something, it is a |
1496 | This is a very special aio request: Instead of doing something, it is a |
| 1409 | container for other aio requests, which is useful if you want to bundle |
1497 | container for other aio requests, which is useful if you want to bundle |
| … | |
… | |
| 1493 | aio_stat [$etcdir, "passwd"], sub { |
1581 | aio_stat [$etcdir, "passwd"], sub { |
| 1494 | # yay |
1582 | # yay |
| 1495 | }; |
1583 | }; |
| 1496 | }; |
1584 | }; |
| 1497 | |
1585 | |
| 1498 | That C<aio_wd> is a request and not a normal function shows that creating |
1586 | The fact that C<aio_wd> is a request and not a normal function shows that |
| 1499 | an IO::AIO::WD object is itself a potentially blocking operation, which is |
1587 | creating an IO::AIO::WD object is itself a potentially blocking operation, |
| 1500 | why it is done asynchronously. |
1588 | which is why it is done asynchronously. |
| 1501 | |
1589 | |
| 1502 | To stat the directory obtained with C<aio_wd> above, one could write |
1590 | To stat the directory obtained with C<aio_wd> above, one could write |
| 1503 | either of the following three request calls: |
1591 | either of the following three request calls: |
| 1504 | |
1592 | |
| 1505 | aio_lstat "/etc" , sub { ... # pathname as normal string |
1593 | aio_lstat "/etc" , sub { ... # pathname as normal string |
| … | |
… | |
| 1522 | There are some caveats: when directories get renamed (or deleted), the |
1610 | There are some caveats: when directories get renamed (or deleted), the |
| 1523 | pathname string doesn't change, so will point to the new directory (or |
1611 | pathname string doesn't change, so will point to the new directory (or |
| 1524 | nowhere at all), while the directory fd, if available on the system, |
1612 | nowhere at all), while the directory fd, if available on the system, |
| 1525 | will still point to the original directory. Most functions accepting a |
1613 | will still point to the original directory. Most functions accepting a |
| 1526 | pathname will use the directory fd on newer systems, and the string on |
1614 | pathname will use the directory fd on newer systems, and the string on |
| 1527 | older systems. Some functions (such as realpath) will always rely on the |
1615 | older systems. Some functions (such as C<aio_realpath>) will always rely on |
| 1528 | string form of the pathname. |
1616 | the string form of the pathname. |
| 1529 | |
1617 | |
| 1530 | So this fucntionality is mainly useful to get some protection against |
1618 | So this functionality is mainly useful to get some protection against |
| 1531 | C<chdir>, to easily get an absolute path out of a relative path for future |
1619 | C<chdir>, to easily get an absolute path out of a relative path for future |
| 1532 | reference, and to speed up doing many operations in the same directory |
1620 | reference, and to speed up doing many operations in the same directory |
| 1533 | (e.g. when stat'ing all files in a directory). |
1621 | (e.g. when stat'ing all files in a directory). |
| 1534 | |
1622 | |
| 1535 | The following functions implement this working directory abstraction: |
1623 | The following functions implement this working directory abstraction: |
| … | |
… | |
| 1548 | passing C<undef> as working directory component of a pathname fails the |
1636 | passing C<undef> as working directory component of a pathname fails the |
| 1549 | request with C<ENOENT>, there is often no need for error checking in the |
1637 | request with C<ENOENT>, there is often no need for error checking in the |
| 1550 | C<aio_wd> callback, as future requests using the value will fail in the |
1638 | C<aio_wd> callback, as future requests using the value will fail in the |
| 1551 | expected way. |
1639 | expected way. |
| 1552 | |
1640 | |
| 1553 | If this call isn't available because your OS lacks it or it couldn't be |
|
|
| 1554 | detected, it will be emulated by calling C<fsync> instead. |
|
|
| 1555 | |
|
|
| 1556 | =item IO::AIO::CWD |
1641 | =item IO::AIO::CWD |
| 1557 | |
1642 | |
| 1558 | This is a compiletime constant (object) that represents the process |
1643 | This is a compiletime constant (object) that represents the process |
| 1559 | current working directory. |
1644 | current working directory. |
| 1560 | |
1645 | |
| 1561 | Specifying this object as working directory object for a pathname is as |
1646 | Specifying this object as working directory object for a pathname is as if |
| 1562 | if the pathname would be specified directly, without a directory object, |
1647 | the pathname would be specified directly, without a directory object. For |
| 1563 | e.g., these calls are functionally identical: |
1648 | example, these calls are functionally identical: |
| 1564 | |
1649 | |
| 1565 | aio_stat "somefile", sub { ... }; |
1650 | aio_stat "somefile", sub { ... }; |
| 1566 | aio_stat [IO::AIO::CWD, "somefile"], sub { ... }; |
1651 | aio_stat [IO::AIO::CWD, "somefile"], sub { ... }; |
| 1567 | |
1652 | |
| 1568 | =back |
1653 | =back |
| 1569 | |
1654 | |
|
|
1655 | To recover the path associated with an IO::AIO::WD object, you can use |
|
|
1656 | C<aio_realpath>: |
|
|
1657 | |
|
|
1658 | aio_realpath $wd, sub { |
|
|
1659 | warn "path is $_[0]\n"; |
|
|
1660 | }; |
|
|
1661 | |
|
|
1662 | Currently, C<aio_statvfs> always, and C<aio_rename> and C<aio_rmdir> |
|
|
1663 | sometimes, fall back to using an absolue path. |
| 1570 | |
1664 | |
| 1571 | =head2 IO::AIO::REQ CLASS |
1665 | =head2 IO::AIO::REQ CLASS |
| 1572 | |
1666 | |
| 1573 | All non-aggregate C<aio_*> functions return an object of this class when |
1667 | All non-aggregate C<aio_*> functions return an object of this class when |
| 1574 | called in non-void context. |
1668 | called in non-void context. |
| … | |
… | |
| 1752 | |
1846 | |
| 1753 | See C<poll_cb> for an example. |
1847 | See C<poll_cb> for an example. |
| 1754 | |
1848 | |
| 1755 | =item IO::AIO::poll_cb |
1849 | =item IO::AIO::poll_cb |
| 1756 | |
1850 | |
| 1757 | Process some outstanding events on the result pipe. You have to call |
1851 | Process some requests that have reached the result phase (i.e. they have |
|
|
1852 | been executed but the results are not yet reported). You have to call |
|
|
1853 | this "regularly" to finish outstanding requests. |
|
|
1854 | |
| 1758 | this regularly. Returns C<0> if all events could be processed (or there |
1855 | Returns C<0> if all events could be processed (or there were no |
| 1759 | were no events to process), or C<-1> if it returned earlier for whatever |
1856 | events to process), or C<-1> if it returned earlier for whatever |
| 1760 | reason. Returns immediately when no events are outstanding. The amount of |
1857 | reason. Returns immediately when no events are outstanding. The amount |
| 1761 | events processed depends on the settings of C<IO::AIO::max_poll_req> and |
1858 | of events processed depends on the settings of C<IO::AIO::max_poll_req>, |
| 1762 | C<IO::AIO::max_poll_time>. |
1859 | C<IO::AIO::max_poll_time> and C<IO::AIO::max_outstanding>. |
| 1763 | |
1860 | |
| 1764 | If not all requests were processed for whatever reason, the filehandle |
1861 | If not all requests were processed for whatever reason, the poll file |
| 1765 | will still be ready when C<poll_cb> returns, so normally you don't have to |
1862 | descriptor will still be ready when C<poll_cb> returns, so normally you |
| 1766 | do anything special to have it called later. |
1863 | don't have to do anything special to have it called later. |
| 1767 | |
1864 | |
| 1768 | Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes |
1865 | Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes |
| 1769 | ready, it can be beneficial to call this function from loops which submit |
1866 | ready, it can be beneficial to call this function from loops which submit |
| 1770 | a lot of requests, to make sure the results get processed when they become |
1867 | a lot of requests, to make sure the results get processed when they become |
| 1771 | available and not just when the loop is finished and the event loop takes |
1868 | available and not just when the loop is finished and the event loop takes |
| … | |
… | |
| 1780 | poll => 'r', async => 1, |
1877 | poll => 'r', async => 1, |
| 1781 | cb => \&IO::AIO::poll_cb); |
1878 | cb => \&IO::AIO::poll_cb); |
| 1782 | |
1879 | |
| 1783 | =item IO::AIO::poll_wait |
1880 | =item IO::AIO::poll_wait |
| 1784 | |
1881 | |
| 1785 | If there are any outstanding requests and none of them in the result |
1882 | Wait until either at least one request is in the result phase or no |
| 1786 | phase, wait till the result filehandle becomes ready for reading (simply |
1883 | requests are outstanding anymore. |
| 1787 | does a C<select> on the filehandle. This is useful if you want to |
1884 | |
| 1788 | synchronously wait for some requests to finish). |
1885 | This is useful if you want to synchronously wait for some requests to |
|
|
1886 | become ready, without actually handling them. |
| 1789 | |
1887 | |
| 1790 | See C<nreqs> for an example. |
1888 | See C<nreqs> for an example. |
| 1791 | |
1889 | |
| 1792 | =item IO::AIO::poll |
1890 | =item IO::AIO::poll |
| 1793 | |
1891 | |
| … | |
… | |
| 1914 | |
2012 | |
| 1915 | This is a very bad function to use in interactive programs because it |
2013 | This is a very bad function to use in interactive programs because it |
| 1916 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
2014 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
| 1917 | use an C<aio_group> together with a feed callback. |
2015 | use an C<aio_group> together with a feed callback. |
| 1918 | |
2016 | |
| 1919 | It's main use is in scripts without an event loop - when you want to stat |
2017 | Its main use is in scripts without an event loop - when you want to stat |
| 1920 | a lot of files, you can write somehting like this: |
2018 | a lot of files, you can write something like this: |
| 1921 | |
2019 | |
| 1922 | IO::AIO::max_outstanding 32; |
2020 | IO::AIO::max_outstanding 32; |
| 1923 | |
2021 | |
| 1924 | for my $path (...) { |
2022 | for my $path (...) { |
| 1925 | aio_stat $path , ...; |
2023 | aio_stat $path , ...; |
| … | |
… | |
| 1964 | |
2062 | |
| 1965 | =back |
2063 | =back |
| 1966 | |
2064 | |
| 1967 | =head3 MISCELLANEOUS FUNCTIONS |
2065 | =head3 MISCELLANEOUS FUNCTIONS |
| 1968 | |
2066 | |
| 1969 | IO::AIO implements some functions that might be useful, but are not |
2067 | IO::AIO implements some functions that are useful when you want to use |
| 1970 | asynchronous. |
2068 | some "Advanced I/O" function not available to in Perl, without going the |
|
|
2069 | "Asynchronous I/O" route. Many of these have an asynchronous C<aio_*> |
|
|
2070 | counterpart. |
| 1971 | |
2071 | |
| 1972 | =over 4 |
2072 | =over 4 |
|
|
2073 | |
|
|
2074 | =item $numfd = IO::AIO::get_fdlimit |
|
|
2075 | |
|
|
2076 | This function is I<EXPERIMENTAL> and subject to change. |
|
|
2077 | |
|
|
2078 | Tries to find the current file descriptor limit and returns it, or |
|
|
2079 | C<undef> and sets C<$!> in case of an error. The limit is one larger than |
|
|
2080 | the highest valid file descriptor number. |
|
|
2081 | |
|
|
2082 | =item IO::AIO::min_fdlimit [$numfd] |
|
|
2083 | |
|
|
2084 | This function is I<EXPERIMENTAL> and subject to change. |
|
|
2085 | |
|
|
2086 | Try to increase the current file descriptor limit(s) to at least C<$numfd> |
|
|
2087 | by changing the soft or hard file descriptor resource limit. If C<$numfd> |
|
|
2088 | is missing, it will try to set a very high limit, although this is not |
|
|
2089 | recommended when you know the actual minimum that you require. |
|
|
2090 | |
|
|
2091 | If the limit cannot be raised enough, the function makes a best-effort |
|
|
2092 | attempt to increase the limit as much as possible, using various |
|
|
2093 | tricks, while still failing. You can query the resulting limit using |
|
|
2094 | C<IO::AIO::get_fdlimit>. |
|
|
2095 | |
|
|
2096 | If an error occurs, returns C<undef> and sets C<$!>, otherwise returns |
|
|
2097 | true. |
| 1973 | |
2098 | |
| 1974 | =item IO::AIO::sendfile $ofh, $ifh, $offset, $count |
2099 | =item IO::AIO::sendfile $ofh, $ifh, $offset, $count |
| 1975 | |
2100 | |
| 1976 | Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>, |
2101 | Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>, |
| 1977 | but is blocking (this makes most sense if you know the input data is |
2102 | but is blocking (this makes most sense if you know the input data is |
| … | |
… | |
| 1994 | =item IO::AIO::madvise $scalar, $offset, $len, $advice |
2119 | =item IO::AIO::madvise $scalar, $offset, $len, $advice |
| 1995 | |
2120 | |
| 1996 | Simply calls the C<posix_madvise> function (see its |
2121 | Simply calls the C<posix_madvise> function (see its |
| 1997 | manpage for details). The following advice constants are |
2122 | manpage for details). The following advice constants are |
| 1998 | available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>, |
2123 | available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>, |
| 1999 | C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>. |
2124 | C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, |
|
|
2125 | C<IO::AIO::MADV_DONTNEED>. |
|
|
2126 | |
|
|
2127 | If C<$offset> is negative, counts from the end. If C<$length> is negative, |
|
|
2128 | the remaining length of the C<$scalar> is used. If possible, C<$length> |
|
|
2129 | will be reduced to fit into the C<$scalar>. |
| 2000 | |
2130 | |
| 2001 | On systems that do not implement C<posix_madvise>, this function returns |
2131 | On systems that do not implement C<posix_madvise>, this function returns |
| 2002 | ENOSYS, otherwise the return value of C<posix_madvise>. |
2132 | ENOSYS, otherwise the return value of C<posix_madvise>. |
| 2003 | |
2133 | |
| 2004 | =item IO::AIO::mprotect $scalar, $offset, $len, $protect |
2134 | =item IO::AIO::mprotect $scalar, $offset, $len, $protect |
| … | |
… | |
| 2006 | Simply calls the C<mprotect> function on the preferably AIO::mmap'ed |
2136 | Simply calls the C<mprotect> function on the preferably AIO::mmap'ed |
| 2007 | $scalar (see its manpage for details). The following protect |
2137 | $scalar (see its manpage for details). The following protect |
| 2008 | constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>, |
2138 | constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>, |
| 2009 | C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>. |
2139 | C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>. |
| 2010 | |
2140 | |
|
|
2141 | If C<$offset> is negative, counts from the end. If C<$length> is negative, |
|
|
2142 | the remaining length of the C<$scalar> is used. If possible, C<$length> |
|
|
2143 | will be reduced to fit into the C<$scalar>. |
|
|
2144 | |
| 2011 | On systems that do not implement C<mprotect>, this function returns |
2145 | On systems that do not implement C<mprotect>, this function returns |
| 2012 | ENOSYS, otherwise the return value of C<mprotect>. |
2146 | ENOSYS, otherwise the return value of C<mprotect>. |
| 2013 | |
2147 | |
| 2014 | =item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
2148 | =item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
| 2015 | |
2149 | |
| 2016 | Memory-maps a file (or anonymous memory range) and attaches it to the |
2150 | Memory-maps a file (or anonymous memory range) and attaches it to the |
| 2017 | given C<$scalar>, which will act like a string scalar. Returns true on |
2151 | given C<$scalar>, which will act like a string scalar. Returns true on |
| 2018 | success, and false otherwise. |
2152 | success, and false otherwise. |
| 2019 | |
2153 | |
|
|
2154 | The scalar must exist, but its contents do not matter - this means you |
|
|
2155 | cannot use a nonexistant array or hash element. When in doubt, C<undef> |
|
|
2156 | the scalar first. |
|
|
2157 | |
| 2020 | The only operations allowed on the scalar are C<substr>/C<vec> that don't |
2158 | The only operations allowed on the mmapped scalar are C<substr>/C<vec>, |
| 2021 | change the string length, and most read-only operations such as copying it |
2159 | which don't change the string length, and most read-only operations such |
| 2022 | or searching it with regexes and so on. |
2160 | as copying it or searching it with regexes and so on. |
| 2023 | |
2161 | |
| 2024 | Anything else is unsafe and will, at best, result in memory leaks. |
2162 | Anything else is unsafe and will, at best, result in memory leaks. |
| 2025 | |
2163 | |
| 2026 | The memory map associated with the C<$scalar> is automatically removed |
2164 | The memory map associated with the C<$scalar> is automatically removed |
| 2027 | when the C<$scalar> is destroyed, or when the C<IO::AIO::mmap> or |
2165 | when the C<$scalar> is undef'd or destroyed, or when the C<IO::AIO::mmap> |
| 2028 | C<IO::AIO::munmap> functions are called. |
2166 | or C<IO::AIO::munmap> functions are called on it. |
| 2029 | |
2167 | |
| 2030 | This calls the C<mmap>(2) function internally. See your system's manual |
2168 | This calls the C<mmap>(2) function internally. See your system's manual |
| 2031 | page for details on the C<$length>, C<$prot> and C<$flags> parameters. |
2169 | page for details on the C<$length>, C<$prot> and C<$flags> parameters. |
| 2032 | |
2170 | |
| 2033 | The C<$length> must be larger than zero and smaller than the actual |
2171 | The C<$length> must be larger than zero and smaller than the actual |
| 2034 | filesize. |
2172 | filesize. |
| 2035 | |
2173 | |
| 2036 | C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>, |
2174 | C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>, |
| 2037 | C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>, |
2175 | C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>, |
| 2038 | |
2176 | |
| 2039 | C<$flags> can be a combination of C<IO::AIO::MAP_SHARED> or |
2177 | C<$flags> can be a combination of |
| 2040 | C<IO::AIO::MAP_PRIVATE>, or a number of system-specific flags (when |
2178 | C<IO::AIO::MAP_SHARED> or |
| 2041 | not available, the are defined as 0): C<IO::AIO::MAP_ANONYMOUS> |
2179 | C<IO::AIO::MAP_PRIVATE>, |
|
|
2180 | or a number of system-specific flags (when not available, the are C<0>): |
| 2042 | (which is set to C<MAP_ANON> if your system only provides this |
2181 | C<IO::AIO::MAP_ANONYMOUS> (which is set to C<MAP_ANON> if your system only provides this constant), |
| 2043 | constant), C<IO::AIO::MAP_HUGETLB>, C<IO::AIO::MAP_LOCKED>, |
2182 | C<IO::AIO::MAP_LOCKED>, |
| 2044 | C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or |
2183 | C<IO::AIO::MAP_NORESERVE>, |
|
|
2184 | C<IO::AIO::MAP_POPULATE>, |
| 2045 | C<IO::AIO::MAP_NONBLOCK> |
2185 | C<IO::AIO::MAP_NONBLOCK>, |
|
|
2186 | C<IO::AIO::MAP_FIXED>, |
|
|
2187 | C<IO::AIO::MAP_GROWSDOWN>, |
|
|
2188 | C<IO::AIO::MAP_32BIT>, |
|
|
2189 | C<IO::AIO::MAP_HUGETLB> or |
|
|
2190 | C<IO::AIO::MAP_STACK>. |
| 2046 | |
2191 | |
| 2047 | If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed. |
2192 | If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed. |
| 2048 | |
2193 | |
| 2049 | C<$offset> is the offset from the start of the file - it generally must be |
2194 | C<$offset> is the offset from the start of the file - it generally must be |
| 2050 | a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>. |
2195 | a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>. |
| … | |
… | |
| 2093 | |
2238 | |
| 2094 | See the C<splice(2)> manpage for details. |
2239 | See the C<splice(2)> manpage for details. |
| 2095 | |
2240 | |
| 2096 | =item IO::AIO::tee $r_fh, $w_fh, $length, $flags |
2241 | =item IO::AIO::tee $r_fh, $w_fh, $length, $flags |
| 2097 | |
2242 | |
| 2098 | Calls the GNU/Linux C<tee(2)> syscall, see it's manpage and the |
2243 | Calls the GNU/Linux C<tee(2)> syscall, see its manpage and the |
| 2099 | description for C<IO::AIO::splice> above for details. |
2244 | description for C<IO::AIO::splice> above for details. |
|
|
2245 | |
|
|
2246 | =item $actual_size = IO::AIO::pipesize $r_fh[, $new_size] |
|
|
2247 | |
|
|
2248 | Attempts to query or change the pipe buffer size. Obviously works only |
|
|
2249 | on pipes, and currently works only on GNU/Linux systems, and fails with |
|
|
2250 | C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer |
|
|
2251 | size on other systems, drop me a note. |
|
|
2252 | |
|
|
2253 | =item ($rfh, $wfh) = IO::AIO::pipe2 [$flags] |
|
|
2254 | |
|
|
2255 | This is a direct interface to the Linux L<pipe2(2)> system call. If |
|
|
2256 | C<$flags> is missing or C<0>, then this should be the same as a call to |
|
|
2257 | perl's built-in C<pipe> function and create a new pipe, and works on |
|
|
2258 | systems that lack the pipe2 syscall. On win32, this case invokes C<_pipe |
|
|
2259 | (..., 4096, O_BINARY)>. |
|
|
2260 | |
|
|
2261 | If C<$flags> is non-zero, it tries to invoke the pipe2 system call with |
|
|
2262 | the given flags (Linux 2.6.27, glibc 2.9). |
|
|
2263 | |
|
|
2264 | On success, the read and write file handles are returned. |
|
|
2265 | |
|
|
2266 | On error, nothing will be returned. If the pipe2 syscall is missing and |
|
|
2267 | C<$flags> is non-zero, fails with C<ENOSYS>. |
|
|
2268 | |
|
|
2269 | Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the |
|
|
2270 | time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and |
|
|
2271 | C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported. |
| 2100 | |
2272 | |
| 2101 | =back |
2273 | =back |
| 2102 | |
2274 | |
| 2103 | =cut |
2275 | =cut |
| 2104 | |
2276 | |
