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 | |
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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 | |
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63 | In addition to asynchronous I/O, this module also exports some rather |
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64 | arcane interfaces, such as C<madvise> or linux's C<splice> system call, |
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65 | which is why the C<A> in C<AIO> can also mean I<advanced>. |
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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 | |
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94 | |
98 | |
95 | # file contents now in $contents |
99 | # file contents now in $contents |
96 | print $contents; |
100 | print $contents; |
97 | |
101 | |
98 | # exit event loop and program |
102 | # exit event loop and program |
99 | EV::unloop; |
103 | EV::break; |
100 | }; |
104 | }; |
101 | }; |
105 | }; |
102 | |
106 | |
103 | # possibly queue up other requests, or open GUI windows, |
107 | # possibly queue up other requests, or open GUI windows, |
104 | # check for sockets etc. etc. |
108 | # check for sockets etc. etc. |
105 | |
109 | |
106 | # process events as long as there are some: |
110 | # process events as long as there are some: |
107 | EV::loop; |
111 | EV::run; |
108 | |
112 | |
109 | =head1 REQUEST ANATOMY AND LIFETIME |
113 | =head1 REQUEST ANATOMY AND LIFETIME |
110 | |
114 | |
111 | 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 |
112 | directly visible to Perl. |
116 | directly visible to Perl. |
… | |
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167 | use common::sense; |
171 | use common::sense; |
168 | |
172 | |
169 | use base 'Exporter'; |
173 | use base 'Exporter'; |
170 | |
174 | |
171 | BEGIN { |
175 | BEGIN { |
172 | our $VERSION = 4.31; |
176 | our $VERSION = 4.35; |
173 | |
177 | |
174 | 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 |
175 | 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 |
176 | aio_scandir aio_symlink aio_readlink aio_realpath aio_sync |
180 | aio_scandir aio_symlink aio_readlink aio_realpath aio_fcntl aio_ioctl |
177 | 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 |
178 | aio_pathsync aio_readahead aio_fiemap |
182 | aio_pathsync aio_readahead aio_fiemap aio_allocate |
179 | aio_rename aio_link aio_move aio_copy aio_group |
183 | aio_rename aio_rename2 aio_link aio_move aio_copy aio_group |
180 | 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 |
181 | aio_chmod aio_utime aio_truncate |
185 | aio_chmod aio_utime aio_truncate |
182 | aio_msync aio_mtouch aio_mlock aio_mlockall |
186 | aio_msync aio_mtouch aio_mlock aio_mlockall |
183 | aio_statvfs |
187 | aio_statvfs |
184 | aio_wd); |
188 | aio_wd); |
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227 | aio_unlink $pathname, $callback->($status) |
231 | aio_unlink $pathname, $callback->($status) |
228 | aio_mknod $pathname, $mode, $dev, $callback->($status) |
232 | aio_mknod $pathname, $mode, $dev, $callback->($status) |
229 | aio_link $srcpath, $dstpath, $callback->($status) |
233 | aio_link $srcpath, $dstpath, $callback->($status) |
230 | aio_symlink $srcpath, $dstpath, $callback->($status) |
234 | aio_symlink $srcpath, $dstpath, $callback->($status) |
231 | aio_readlink $pathname, $callback->($link) |
235 | aio_readlink $pathname, $callback->($link) |
232 | aio_realpath $pathname, $callback->($link) |
236 | aio_realpath $pathname, $callback->($path) |
233 | 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) |
234 | aio_mkdir $pathname, $mode, $callback->($status) |
239 | aio_mkdir $pathname, $mode, $callback->($status) |
235 | aio_rmdir $pathname, $callback->($status) |
240 | aio_rmdir $pathname, $callback->($status) |
236 | aio_readdir $pathname, $callback->($entries) |
241 | aio_readdir $pathname, $callback->($entries) |
237 | aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
242 | aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
238 | IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST |
243 | IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST |
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240 | aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs) |
245 | aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs) |
241 | aio_load $pathname, $data, $callback->($status) |
246 | aio_load $pathname, $data, $callback->($status) |
242 | aio_copy $srcpath, $dstpath, $callback->($status) |
247 | aio_copy $srcpath, $dstpath, $callback->($status) |
243 | aio_move $srcpath, $dstpath, $callback->($status) |
248 | aio_move $srcpath, $dstpath, $callback->($status) |
244 | aio_rmtree $pathname, $callback->($status) |
249 | aio_rmtree $pathname, $callback->($status) |
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250 | aio_fcntl $fh, $cmd, $arg, $callback->($status) |
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251 | aio_ioctl $fh, $request, $buf, $callback->($status) |
245 | aio_sync $callback->($status) |
252 | aio_sync $callback->($status) |
246 | aio_syncfs $fh, $callback->($status) |
253 | aio_syncfs $fh, $callback->($status) |
247 | aio_fsync $fh, $callback->($status) |
254 | aio_fsync $fh, $callback->($status) |
248 | aio_fdatasync $fh, $callback->($status) |
255 | aio_fdatasync $fh, $callback->($status) |
249 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
256 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
250 | aio_pathsync $pathname, $callback->($status) |
257 | aio_pathsync $pathname, $callback->($status) |
251 | aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
258 | aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status) |
252 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
259 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
253 | aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
260 | aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
254 | aio_mlockall $flags, $callback->($status) |
261 | aio_mlockall $flags, $callback->($status) |
255 | aio_group $callback->(...) |
262 | aio_group $callback->(...) |
256 | aio_nop $callback->() |
263 | aio_nop $callback->() |
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270 | IO::AIO::idle_timeout $seconds |
277 | IO::AIO::idle_timeout $seconds |
271 | IO::AIO::max_outstanding $maxreqs |
278 | IO::AIO::max_outstanding $maxreqs |
272 | IO::AIO::nreqs |
279 | IO::AIO::nreqs |
273 | IO::AIO::nready |
280 | IO::AIO::nready |
274 | IO::AIO::npending |
281 | IO::AIO::npending |
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282 | $nfd = IO::AIO::get_fdlimit [EXPERIMENTAL] |
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283 | IO::AIO::min_fdlimit $nfd [EXPERIMENTAL] |
275 | |
284 | |
276 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
285 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
277 | IO::AIO::fadvise $fh, $offset, $len, $advice |
286 | IO::AIO::fadvise $fh, $offset, $len, $advice |
278 | IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]] |
287 | IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]] |
279 | IO::AIO::munmap $scalar |
288 | IO::AIO::munmap $scalar |
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394 | following POSIX and non-POSIX constants are available (missing ones on |
403 | following POSIX and non-POSIX constants are available (missing ones on |
395 | your system are, as usual, C<0>): |
404 | your system are, as usual, C<0>): |
396 | |
405 | |
397 | 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>, |
398 | 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>, |
399 | 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>. |
400 | |
409 | |
401 | |
410 | |
402 | =item aio_close $fh, $callback->($status) |
411 | =item aio_close $fh, $callback->($status) |
403 | |
412 | |
404 | Asynchronously close a file and call the callback with the result |
413 | Asynchronously close a file and call the callback with the result |
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439 | =item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
448 | =item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
440 | |
449 | |
441 | =item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
450 | =item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
442 | |
451 | |
443 | 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 |
444 | 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 |
445 | 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 |
446 | error, just like the syscall). |
455 | error, just like the syscall). |
447 | |
456 | |
448 | 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 |
449 | offset plus the actual number of bytes read. |
458 | offset plus the actual number of bytes read. |
450 | |
459 | |
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508 | As native sendfile syscalls (as practically any non-POSIX interface hacked |
517 | As native sendfile syscalls (as practically any non-POSIX interface hacked |
509 | 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 |
510 | 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 |
511 | 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, |
512 | 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> - |
513 | fewre bytes than expected might have been transferred. |
522 | fewer bytes than expected might have been transferred. |
514 | |
523 | |
515 | |
524 | |
516 | =item aio_readahead $fh,$offset,$length, $callback->($retval) |
525 | =item aio_readahead $fh,$offset,$length, $callback->($retval) |
517 | |
526 | |
518 | 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 |
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522 | 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 |
523 | 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 |
524 | (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 |
525 | file. The current file offset of the file is left unchanged. |
534 | file. The current file offset of the file is left unchanged. |
526 | |
535 | |
527 | 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 |
528 | 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. |
529 | |
538 | |
530 | |
539 | |
531 | =item aio_stat $fh_or_path, $callback->($status) |
540 | =item aio_stat $fh_or_path, $callback->($status) |
532 | |
541 | |
533 | =item aio_lstat $fh, $callback->($status) |
542 | =item aio_lstat $fh, $callback->($status) |
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626 | 0x00001373 devfs |
635 | 0x00001373 devfs |
627 | 0x00001cd1 devpts |
636 | 0x00001cd1 devpts |
628 | 0x0000f15f ecryptfs |
637 | 0x0000f15f ecryptfs |
629 | 0x00414a53 efs |
638 | 0x00414a53 efs |
630 | 0x0000137d ext |
639 | 0x0000137d ext |
631 | 0x0000ef53 ext2/ext3 |
640 | 0x0000ef53 ext2/ext3/ext4 |
632 | 0x0000ef51 ext2 |
641 | 0x0000ef51 ext2 |
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642 | 0xf2f52010 f2fs |
633 | 0x00004006 fat |
643 | 0x00004006 fat |
634 | 0x65735546 fuseblk |
644 | 0x65735546 fuseblk |
635 | 0x65735543 fusectl |
645 | 0x65735543 fusectl |
636 | 0x0bad1dea futexfs |
646 | 0x0bad1dea futexfs |
637 | 0x01161970 gfs2 |
647 | 0x01161970 gfs2 |
638 | 0x47504653 gpfs |
648 | 0x47504653 gpfs |
639 | 0x00004244 hfs |
649 | 0x00004244 hfs |
640 | 0xf995e849 hpfs |
650 | 0xf995e849 hpfs |
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651 | 0x00c0ffee hostfs |
641 | 0x958458f6 hugetlbfs |
652 | 0x958458f6 hugetlbfs |
642 | 0x2bad1dea inotifyfs |
653 | 0x2bad1dea inotifyfs |
643 | 0x00009660 isofs |
654 | 0x00009660 isofs |
644 | 0x000072b6 jffs2 |
655 | 0x000072b6 jffs2 |
645 | 0x3153464a jfs |
656 | 0x3153464a jfs |
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… | |
660 | 0x00009fa1 openprom |
671 | 0x00009fa1 openprom |
661 | 0x7461636F ocfs2 |
672 | 0x7461636F ocfs2 |
662 | 0x00009fa0 proc |
673 | 0x00009fa0 proc |
663 | 0x6165676c pstorefs |
674 | 0x6165676c pstorefs |
664 | 0x0000002f qnx4 |
675 | 0x0000002f qnx4 |
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676 | 0x68191122 qnx6 |
665 | 0x858458f6 ramfs |
677 | 0x858458f6 ramfs |
666 | 0x52654973 reiserfs |
678 | 0x52654973 reiserfs |
667 | 0x00007275 romfs |
679 | 0x00007275 romfs |
668 | 0x67596969 rpc_pipefs |
680 | 0x67596969 rpc_pipefs |
669 | 0x73636673 securityfs |
681 | 0x73636673 securityfs |
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722 | Works like truncate(2) or ftruncate(2). |
734 | Works like truncate(2) or ftruncate(2). |
723 | |
735 | |
724 | |
736 | |
725 | =item aio_allocate $fh, $mode, $offset, $len, $callback->($status) |
737 | =item aio_allocate $fh, $mode, $offset, $len, $callback->($status) |
726 | |
738 | |
727 | 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 |
728 | linux C<fallocate> docuemntation for details. |
740 | linux C<fallocate> documentation for details. |
729 | |
741 | |
730 | 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 |
731 | 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>, |
732 | IO::AIO::FALLOC_FL_KEEP_SIZE>, to deallocate a file range. |
744 | to deallocate a file range. |
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745 | |
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746 | IO::AIO also supports C<FALLOC_FL_COLLAPSE_RANGE>, to remove a range |
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747 | (without leaving a hole), C<FALLOC_FL_ZERO_RANGE>, to zero a range, |
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748 | C<FALLOC_FL_INSERT_RANGE> to insert a range and C<FALLOC_FL_UNSHARE_RANGE> |
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749 | to unshare shared blocks (see your L<fallocate(2)> manpage). |
733 | |
750 | |
734 | 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 |
735 | C<f_bsize> returned by C<statvfs>. |
752 | C<f_bsize> returned by C<statvfs>, but different filesystems and filetypes |
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753 | can dictate other limitations. |
736 | |
754 | |
737 | 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 |
738 | 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>. |
739 | |
757 | |
740 | |
758 | |
… | |
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797 | rename(2) and call the callback with the result code. |
815 | rename(2) and call the callback with the result code. |
798 | |
816 | |
799 | On systems that support the AIO::WD working directory abstraction |
817 | On systems that support the AIO::WD working directory abstraction |
800 | natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead |
818 | natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead |
801 | of failing, C<rename> is called on the absolute path of C<$wd>. |
819 | of failing, C<rename> is called on the absolute path of C<$wd>. |
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820 | |
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821 | |
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822 | =item aio_rename2 $srcpath, $dstpath, $flags, $callback->($status) |
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823 | |
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824 | Basically a version of C<aio_rename> with an additional C<$flags> |
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825 | argument. Calling this with C<$flags=0> is the same as calling |
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826 | C<aio_rename>. |
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827 | |
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828 | Non-zero flags are currently only supported on GNU/Linux systems that |
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829 | support renameat2. Other systems fail with C<ENOSYS> in this case. |
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830 | |
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831 | The following constants are available (missing ones are, as usual C<0>), |
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832 | see renameat2(2) for details: |
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833 | |
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834 | C<IO::AIO::RENAME_NOREPLACE>, C<IO::AIO::RENAME_EXCHANGE> |
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835 | and C<IO::AIO::RENAME_WHITEOUT>. |
802 | |
836 | |
803 | |
837 | |
804 | =item aio_mkdir $pathname, $mode, $callback->($status) |
838 | =item aio_mkdir $pathname, $mode, $callback->($status) |
805 | |
839 | |
806 | Asynchronously mkdir (create) a directory and call the callback with |
840 | Asynchronously mkdir (create) a directory and call the callback with |
… | |
… | |
925 | =item aio_copy $srcpath, $dstpath, $callback->($status) |
959 | =item aio_copy $srcpath, $dstpath, $callback->($status) |
926 | |
960 | |
927 | 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 |
928 | 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 |
929 | a status of C<0> (ok) or C<-1> (error, see C<$!>). |
963 | a status of C<0> (ok) or C<-1> (error, see C<$!>). |
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964 | |
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965 | Existing destination files will be truncated. |
930 | |
966 | |
931 | This is a composite request that creates the destination file with |
967 | This is a composite request that creates the destination file with |
932 | 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 |
933 | C<aio_sendfile>, followed by restoring atime, mtime, access mode and |
969 | C<aio_sendfile>, followed by restoring atime, mtime, access mode and |
934 | uid/gid, in that order. |
970 | uid/gid, in that order. |
… | |
… | |
1044 | 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 |
1045 | 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 |
1046 | names, directories you can recurse into (directories), and ones you cannot |
1082 | names, directories you can recurse into (directories), and ones you cannot |
1047 | recurse into (everything else, including symlinks to directories). |
1083 | recurse into (everything else, including symlinks to directories). |
1048 | |
1084 | |
1049 | 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. |
1050 | C<$maxreq> specifies the maximum number of outstanding aio requests that |
1086 | C<$maxreq> specifies the maximum number of outstanding aio requests that |
1051 | 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 |
1052 | will be chosen (currently 4). |
1088 | will be chosen (currently 4). |
1053 | |
1089 | |
1054 | On error, the callback is called without arguments, otherwise it receives |
1090 | On error, the callback is called without arguments, otherwise it receives |
… | |
… | |
1220 | }; |
1256 | }; |
1221 | |
1257 | |
1222 | $grp |
1258 | $grp |
1223 | } |
1259 | } |
1224 | |
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>, |
|
|
1304 | |
1225 | =item aio_sync $callback->($status) |
1305 | =item aio_sync $callback->($status) |
1226 | |
1306 | |
1227 | Asynchronously call sync and call the callback when finished. |
1307 | Asynchronously call sync and call the callback when finished. |
1228 | |
1308 | |
1229 | =item aio_fsync $fh, $callback->($status) |
1309 | =item aio_fsync $fh, $callback->($status) |
… | |
… | |
1297 | }; |
1377 | }; |
1298 | |
1378 | |
1299 | $grp |
1379 | $grp |
1300 | } |
1380 | } |
1301 | |
1381 | |
1302 | =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) |
1303 | |
1383 | |
1304 | 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 |
1305 | 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 |
1306 | 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 |
1307 | 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 |
… | |
… | |
1309 | |
1389 | |
1310 | 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 |
1311 | 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 |
1312 | 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> |
1313 | 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 |
1314 | 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 |
1315 | C<IO::AIO::MS_SYNC>. |
1395 | C<IO::AIO::MS_INVALIDATE>. |
1316 | |
1396 | |
1317 | =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) |
1318 | |
1398 | |
1319 | 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 |
1320 | scalars. |
1400 | scalars. |
… | |
… | |
1403 | 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>, |
1404 | 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>, |
1405 | 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 |
1406 | C<IO::AIO::FIEMAP_EXTENT_SHARED>. |
1486 | C<IO::AIO::FIEMAP_EXTENT_SHARED>. |
1407 | |
1487 | |
1408 | 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 |
1409 | 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 |
1410 | 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 |
1411 | 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>. |
1412 | |
1493 | |
1413 | =item aio_group $callback->(...) |
1494 | =item aio_group $callback->(...) |
1414 | |
1495 | |
1415 | This is a very special aio request: Instead of doing something, it is a |
1496 | This is a very special aio request: Instead of doing something, it is a |
1416 | container for other aio requests, which is useful if you want to bundle |
1497 | container for other aio requests, which is useful if you want to bundle |
… | |
… | |
1500 | aio_stat [$etcdir, "passwd"], sub { |
1581 | aio_stat [$etcdir, "passwd"], sub { |
1501 | # yay |
1582 | # yay |
1502 | }; |
1583 | }; |
1503 | }; |
1584 | }; |
1504 | |
1585 | |
1505 | 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 |
1506 | 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, |
1507 | why it is done asynchronously. |
1588 | which is why it is done asynchronously. |
1508 | |
1589 | |
1509 | 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 |
1510 | either of the following three request calls: |
1591 | either of the following three request calls: |
1511 | |
1592 | |
1512 | aio_lstat "/etc" , sub { ... # pathname as normal string |
1593 | aio_lstat "/etc" , sub { ... # pathname as normal string |
… | |
… | |
1529 | There are some caveats: when directories get renamed (or deleted), the |
1610 | There are some caveats: when directories get renamed (or deleted), the |
1530 | 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 |
1531 | 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, |
1532 | will still point to the original directory. Most functions accepting a |
1613 | will still point to the original directory. Most functions accepting a |
1533 | 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 |
1534 | 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 |
1535 | string form of the pathname. |
1616 | the string form of the pathname. |
1536 | |
1617 | |
1537 | So this functionality is mainly useful to get some protection against |
1618 | So this functionality is mainly useful to get some protection against |
1538 | 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 |
1539 | 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 |
1540 | (e.g. when stat'ing all files in a directory). |
1621 | (e.g. when stat'ing all files in a directory). |
… | |
… | |
1932 | 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 |
1933 | 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 |
1934 | use an C<aio_group> together with a feed callback. |
2015 | use an C<aio_group> together with a feed callback. |
1935 | |
2016 | |
1936 | Its 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 |
1937 | a lot of files, you can write somehting like this: |
2018 | a lot of files, you can write something like this: |
1938 | |
2019 | |
1939 | IO::AIO::max_outstanding 32; |
2020 | IO::AIO::max_outstanding 32; |
1940 | |
2021 | |
1941 | for my $path (...) { |
2022 | for my $path (...) { |
1942 | aio_stat $path , ...; |
2023 | aio_stat $path , ...; |
… | |
… | |
1987 | some "Advanced I/O" function not available to in Perl, without going the |
2068 | some "Advanced I/O" function not available to in Perl, without going the |
1988 | "Asynchronous I/O" route. Many of these have an asynchronous C<aio_*> |
2069 | "Asynchronous I/O" route. Many of these have an asynchronous C<aio_*> |
1989 | counterpart. |
2070 | counterpart. |
1990 | |
2071 | |
1991 | =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. |
1992 | |
2098 | |
1993 | =item IO::AIO::sendfile $ofh, $ifh, $offset, $count |
2099 | =item IO::AIO::sendfile $ofh, $ifh, $offset, $count |
1994 | |
2100 | |
1995 | 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>, |
1996 | 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 |
… | |
… | |
2013 | =item IO::AIO::madvise $scalar, $offset, $len, $advice |
2119 | =item IO::AIO::madvise $scalar, $offset, $len, $advice |
2014 | |
2120 | |
2015 | Simply calls the C<posix_madvise> function (see its |
2121 | Simply calls the C<posix_madvise> function (see its |
2016 | manpage for details). The following advice constants are |
2122 | manpage for details). The following advice constants are |
2017 | available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>, |
2123 | available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>, |
2018 | C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>. |
2124 | C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, |
|
|
2125 | C<IO::AIO::MADV_DONTNEED>. |
|
|
2126 | |
|
|
2127 | If C<$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>. |
2019 | |
2130 | |
2020 | 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 |
2021 | ENOSYS, otherwise the return value of C<posix_madvise>. |
2132 | ENOSYS, otherwise the return value of C<posix_madvise>. |
2022 | |
2133 | |
2023 | =item IO::AIO::mprotect $scalar, $offset, $len, $protect |
2134 | =item IO::AIO::mprotect $scalar, $offset, $len, $protect |
… | |
… | |
2025 | 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 |
2026 | $scalar (see its manpage for details). The following protect |
2137 | $scalar (see its manpage for details). The following protect |
2027 | constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>, |
2138 | constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>, |
2028 | C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>. |
2139 | C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>. |
2029 | |
2140 | |
|
|
2141 | If C<$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 | |
2030 | On systems that do not implement C<mprotect>, this function returns |
2145 | On systems that do not implement C<mprotect>, this function returns |
2031 | ENOSYS, otherwise the return value of C<mprotect>. |
2146 | ENOSYS, otherwise the return value of C<mprotect>. |
2032 | |
2147 | |
2033 | =item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
2148 | =item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
2034 | |
2149 | |
2035 | Memory-maps a file (or anonymous memory range) and attaches it to the |
2150 | Memory-maps a file (or anonymous memory range) and attaches it to the |
2036 | given C<$scalar>, which will act like a string scalar. Returns true on |
2151 | given C<$scalar>, which will act like a string scalar. Returns true on |
2037 | success, and false otherwise. |
2152 | success, and false otherwise. |
2038 | |
2153 | |
|
|
2154 | The scalar must exist, but its contents do not matter - this means you |
|
|
2155 | cannot use a nonexistant array or hash element. When in doubt, C<undef> |
|
|
2156 | the scalar first. |
|
|
2157 | |
2039 | The only operations allowed on the scalar are C<substr>/C<vec> that don't |
2158 | The only operations allowed on the mmapped scalar are C<substr>/C<vec>, |
2040 | change the string length, and most read-only operations such as copying it |
2159 | which don't change the string length, and most read-only operations such |
2041 | or searching it with regexes and so on. |
2160 | as copying it or searching it with regexes and so on. |
2042 | |
2161 | |
2043 | Anything else is unsafe and will, at best, result in memory leaks. |
2162 | Anything else is unsafe and will, at best, result in memory leaks. |
2044 | |
2163 | |
2045 | The memory map associated with the C<$scalar> is automatically removed |
2164 | The memory map associated with the C<$scalar> is automatically removed |
2046 | when the C<$scalar> is destroyed, or when the C<IO::AIO::mmap> or |
2165 | when the C<$scalar> is undef'd or destroyed, or when the C<IO::AIO::mmap> |
2047 | C<IO::AIO::munmap> functions are called. |
2166 | or C<IO::AIO::munmap> functions are called on it. |
2048 | |
2167 | |
2049 | This calls the C<mmap>(2) function internally. See your system's manual |
2168 | This calls the C<mmap>(2) function internally. See your system's manual |
2050 | page for details on the C<$length>, C<$prot> and C<$flags> parameters. |
2169 | page for details on the C<$length>, C<$prot> and C<$flags> parameters. |
2051 | |
2170 | |
2052 | The C<$length> must be larger than zero and smaller than the actual |
2171 | The C<$length> must be larger than zero and smaller than the actual |
2053 | filesize. |
2172 | filesize. |
2054 | |
2173 | |
2055 | C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>, |
2174 | C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>, |
2056 | C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>, |
2175 | C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>, |
2057 | |
2176 | |
2058 | C<$flags> can be a combination of C<IO::AIO::MAP_SHARED> or |
2177 | C<$flags> can be a combination of |
2059 | C<IO::AIO::MAP_PRIVATE>, or a number of system-specific flags (when |
2178 | C<IO::AIO::MAP_SHARED> or |
2060 | not available, the are defined as 0): C<IO::AIO::MAP_ANONYMOUS> |
2179 | C<IO::AIO::MAP_PRIVATE>, |
|
|
2180 | or a number of system-specific flags (when not available, the are C<0>): |
2061 | (which is set to C<MAP_ANON> if your system only provides this |
2181 | C<IO::AIO::MAP_ANONYMOUS> (which is set to C<MAP_ANON> if your system only provides this constant), |
2062 | constant), C<IO::AIO::MAP_HUGETLB>, C<IO::AIO::MAP_LOCKED>, |
2182 | C<IO::AIO::MAP_LOCKED>, |
2063 | C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or |
2183 | C<IO::AIO::MAP_NORESERVE>, |
|
|
2184 | C<IO::AIO::MAP_POPULATE>, |
2064 | C<IO::AIO::MAP_NONBLOCK> |
2185 | C<IO::AIO::MAP_NONBLOCK>, |
|
|
2186 | C<IO::AIO::MAP_FIXED>, |
|
|
2187 | C<IO::AIO::MAP_GROWSDOWN>, |
|
|
2188 | C<IO::AIO::MAP_32BIT>, |
|
|
2189 | C<IO::AIO::MAP_HUGETLB> or |
|
|
2190 | C<IO::AIO::MAP_STACK>. |
2065 | |
2191 | |
2066 | If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed. |
2192 | If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed. |
2067 | |
2193 | |
2068 | C<$offset> is the offset from the start of the file - it generally must be |
2194 | C<$offset> is the offset from the start of the file - it generally must be |
2069 | a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>. |
2195 | a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>. |
… | |
… | |
2121 | |
2247 | |
2122 | Attempts to query or change the pipe buffer size. Obviously works only |
2248 | Attempts to query or change the pipe buffer size. Obviously works only |
2123 | on pipes, and currently works only on GNU/Linux systems, and fails with |
2249 | on pipes, and currently works only on GNU/Linux systems, and fails with |
2124 | C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer |
2250 | C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer |
2125 | size on other systems, drop me a note. |
2251 | size on other systems, drop me a note. |
|
|
2252 | |
|
|
2253 | =item ($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. |
2126 | |
2272 | |
2127 | =back |
2273 | =back |
2128 | |
2274 | |
2129 | =cut |
2275 | =cut |
2130 | |
2276 | |