| … | |
… | |
| 64 | |
64 | |
| 65 | EXAMPLE |
65 | EXAMPLE |
| 66 | This is a simple example that uses the EV module and loads /etc/passwd |
66 | This is a simple example that uses the EV module and loads /etc/passwd |
| 67 | asynchronously: |
67 | asynchronously: |
| 68 | |
68 | |
| 69 | use Fcntl; |
|
|
| 70 | use EV; |
69 | use EV; |
| 71 | use IO::AIO; |
70 | use IO::AIO; |
| 72 | |
71 | |
| 73 | # register the IO::AIO callback with EV |
72 | # register the IO::AIO callback with EV |
| 74 | my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb; |
73 | my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb; |
| … | |
… | |
| 146 | the actual aio request is severed and calling its methods will |
145 | the actual aio request is severed and calling its methods will |
| 147 | either do nothing or result in a runtime error). |
146 | either do nothing or result in a runtime error). |
| 148 | |
147 | |
| 149 | FUNCTIONS |
148 | FUNCTIONS |
| 150 | QUICK OVERVIEW |
149 | QUICK OVERVIEW |
| 151 | This section simply lists the prototypes of the most important functions |
150 | This section simply lists the prototypes most of the functions for quick |
| 152 | for quick reference. See the following sections for function-by-function |
151 | reference. See the following sections for function-by-function |
| 153 | documentation. |
152 | documentation. |
| 154 | |
153 | |
| 155 | aio_wd $pathname, $callback->($wd) |
154 | aio_wd $pathname, $callback->($wd) |
| 156 | aio_open $pathname, $flags, $mode, $callback->($fh) |
155 | aio_open $pathname, $flags, $mode, $callback->($fh) |
| 157 | aio_close $fh, $callback->($status) |
156 | aio_close $fh, $callback->($status) |
|
|
157 | aio_seek $fh,$offset,$whence, $callback->($offs) |
| 158 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
158 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
| 159 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
159 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
| 160 | aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval) |
160 | aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval) |
| 161 | aio_readahead $fh,$offset,$length, $callback->($retval) |
161 | aio_readahead $fh,$offset,$length, $callback->($retval) |
| 162 | aio_stat $fh_or_path, $callback->($status) |
162 | aio_stat $fh_or_path, $callback->($status) |
| 163 | aio_lstat $fh, $callback->($status) |
163 | aio_lstat $fh, $callback->($status) |
| 164 | aio_statvfs $fh_or_path, $callback->($statvfs) |
164 | aio_statvfs $fh_or_path, $callback->($statvfs) |
| 165 | aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
165 | aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
| 166 | aio_chown $fh_or_path, $uid, $gid, $callback->($status) |
166 | aio_chown $fh_or_path, $uid, $gid, $callback->($status) |
|
|
167 | aio_chmod $fh_or_path, $mode, $callback->($status) |
| 167 | aio_truncate $fh_or_path, $offset, $callback->($status) |
168 | aio_truncate $fh_or_path, $offset, $callback->($status) |
| 168 | aio_chmod $fh_or_path, $mode, $callback->($status) |
169 | aio_allocate $fh, $mode, $offset, $len, $callback->($status) |
|
|
170 | aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents) |
| 169 | aio_unlink $pathname, $callback->($status) |
171 | aio_unlink $pathname, $callback->($status) |
| 170 | aio_mknod $pathname, $mode, $dev, $callback->($status) |
172 | aio_mknod $pathname, $mode, $dev, $callback->($status) |
| 171 | aio_link $srcpath, $dstpath, $callback->($status) |
173 | aio_link $srcpath, $dstpath, $callback->($status) |
| 172 | aio_symlink $srcpath, $dstpath, $callback->($status) |
174 | aio_symlink $srcpath, $dstpath, $callback->($status) |
| 173 | aio_readlink $pathname, $callback->($link) |
175 | aio_readlink $pathname, $callback->($link) |
| 174 | aio_realpath $pathname, $callback->($link) |
176 | aio_realpath $pathname, $callback->($path) |
| 175 | aio_rename $srcpath, $dstpath, $callback->($status) |
177 | aio_rename $srcpath, $dstpath, $callback->($status) |
| 176 | aio_mkdir $pathname, $mode, $callback->($status) |
178 | aio_mkdir $pathname, $mode, $callback->($status) |
| 177 | aio_rmdir $pathname, $callback->($status) |
179 | aio_rmdir $pathname, $callback->($status) |
| 178 | aio_readdir $pathname, $callback->($entries) |
180 | aio_readdir $pathname, $callback->($entries) |
| 179 | aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
181 | aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
| … | |
… | |
| 215 | IO::AIO::nready |
217 | IO::AIO::nready |
| 216 | IO::AIO::npending |
218 | IO::AIO::npending |
| 217 | |
219 | |
| 218 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
220 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
| 219 | IO::AIO::fadvise $fh, $offset, $len, $advice |
221 | IO::AIO::fadvise $fh, $offset, $len, $advice |
|
|
222 | IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]] |
|
|
223 | IO::AIO::munmap $scalar |
| 220 | IO::AIO::madvise $scalar, $offset, $length, $advice |
224 | IO::AIO::madvise $scalar, $offset, $length, $advice |
| 221 | IO::AIO::mprotect $scalar, $offset, $length, $protect |
225 | IO::AIO::mprotect $scalar, $offset, $length, $protect |
| 222 | IO::AIO::munlock $scalar, $offset = 0, $length = undef |
226 | IO::AIO::munlock $scalar, $offset = 0, $length = undef |
| 223 | IO::AIO::munlockall |
227 | IO::AIO::munlockall |
| 224 | |
228 | |
| 225 | AIO REQUEST FUNCTIONS |
229 | API NOTES |
| 226 | All the "aio_*" calls are more or less thin wrappers around the syscall |
230 | All the "aio_*" calls are more or less thin wrappers around the syscall |
| 227 | with the same name (sans "aio_"). The arguments are similar or |
231 | with the same name (sans "aio_"). The arguments are similar or |
| 228 | identical, and they all accept an additional (and optional) $callback |
232 | identical, and they all accept an additional (and optional) $callback |
| 229 | argument which must be a code reference. This code reference will be |
233 | argument which must be a code reference. This code reference will be |
| 230 | called after the syscall has been executed in an asynchronous fashion. |
234 | called after the syscall has been executed in an asynchronous fashion. |
| … | |
… | |
| 260 | else to ensure your scalar has the correct contents. |
264 | else to ensure your scalar has the correct contents. |
| 261 | |
265 | |
| 262 | This works, btw. independent of the internal UTF-8 bit, which IO::AIO |
266 | This works, btw. independent of the internal UTF-8 bit, which IO::AIO |
| 263 | handles correctly whether it is set or not. |
267 | handles correctly whether it is set or not. |
| 264 | |
268 | |
|
|
269 | AIO REQUEST FUNCTIONS |
| 265 | $prev_pri = aioreq_pri [$pri] |
270 | $prev_pri = aioreq_pri [$pri] |
| 266 | Returns the priority value that would be used for the next request |
271 | Returns the priority value that would be used for the next request |
| 267 | and, if $pri is given, sets the priority for the next aio request. |
272 | and, if $pri is given, sets the priority for the next aio request. |
| 268 | |
273 | |
| 269 | The default priority is 0, the minimum and maximum priorities are -4 |
274 | The default priority is 0, the minimum and maximum priorities are -4 |
| … | |
… | |
| 291 | Similar to "aioreq_pri", but subtracts the given value from the |
296 | Similar to "aioreq_pri", but subtracts the given value from the |
| 292 | current priority, so the effect is cumulative. |
297 | current priority, so the effect is cumulative. |
| 293 | |
298 | |
| 294 | aio_open $pathname, $flags, $mode, $callback->($fh) |
299 | aio_open $pathname, $flags, $mode, $callback->($fh) |
| 295 | Asynchronously open or create a file and call the callback with a |
300 | Asynchronously open or create a file and call the callback with a |
| 296 | newly created filehandle for the file. |
301 | newly created filehandle for the file (or "undef" in case of an |
|
|
302 | error). |
| 297 | |
303 | |
| 298 | The pathname passed to "aio_open" must be absolute. See API NOTES, |
304 | The pathname passed to "aio_open" must be absolute. See API NOTES, |
| 299 | above, for an explanation. |
305 | above, for an explanation. |
| 300 | |
306 | |
| 301 | The $flags argument is a bitmask. See the "Fcntl" module for a list. |
307 | The $flags argument is a bitmask. See the "Fcntl" module for a list. |
| … | |
… | |
| 340 | will use dup2 to overwrite the file descriptor with the write-end of |
346 | will use dup2 to overwrite the file descriptor with the write-end of |
| 341 | a pipe (the pipe fd will be created on demand and will be cached). |
347 | a pipe (the pipe fd will be created on demand and will be cached). |
| 342 | |
348 | |
| 343 | Or in other words: the file descriptor will be closed, but it will |
349 | Or in other words: the file descriptor will be closed, but it will |
| 344 | not be free for reuse until the perl filehandle is closed. |
350 | not be free for reuse until the perl filehandle is closed. |
|
|
351 | |
|
|
352 | aio_seek $fh, $offset, $whence, $callback->($offs) |
|
|
353 | Seeks the filehandle to the new $offset, similarly to perl's |
|
|
354 | "sysseek". The $whence can use the traditional values (0 for |
|
|
355 | "IO::AIO::SEEK_SET", 1 for "IO::AIO::SEEK_CUR" or 2 for |
|
|
356 | "IO::AIO::SEEK_END"). |
|
|
357 | |
|
|
358 | The resulting absolute offset will be passed to the callback, or -1 |
|
|
359 | in case of an error. |
|
|
360 | |
|
|
361 | In theory, the $whence constants could be different than the |
|
|
362 | corresponding values from Fcntl, but perl guarantees they are the |
|
|
363 | same, so don't panic. |
|
|
364 | |
|
|
365 | As a GNU/Linux (and maybe Solaris) extension, also the constants |
|
|
366 | "IO::AIO::SEEK_DATA" and "IO::AIO::SEEK_HOLE" are available, if they |
|
|
367 | could be found. No guarantees about suitability for use in |
|
|
368 | "aio_seek" or Perl's "sysseek" can be made though, although I would |
|
|
369 | naively assume they "just work". |
| 345 | |
370 | |
| 346 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
371 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
| 347 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
372 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
| 348 | Reads or writes $length bytes from or to the specified $fh and |
373 | Reads or writes $length bytes from or to the specified $fh and |
| 349 | $offset into the scalar given by $data and offset $dataoffset and |
374 | $offset into the scalar given by $data and offset $dataoffset and |
| … | |
… | |
| 504 | namemax => 255, |
529 | namemax => 255, |
| 505 | frsize => 1024, |
530 | frsize => 1024, |
| 506 | fsid => 1810 |
531 | fsid => 1810 |
| 507 | } |
532 | } |
| 508 | |
533 | |
|
|
534 | Here is a (likely partial - send me updates!) list of fsid values |
|
|
535 | used by Linux - it is safe to hardcode these when $^O is "linux": |
|
|
536 | |
|
|
537 | 0x0000adf5 adfs |
|
|
538 | 0x0000adff affs |
|
|
539 | 0x5346414f afs |
|
|
540 | 0x09041934 anon-inode filesystem |
|
|
541 | 0x00000187 autofs |
|
|
542 | 0x42465331 befs |
|
|
543 | 0x1badface bfs |
|
|
544 | 0x42494e4d binfmt_misc |
|
|
545 | 0x9123683e btrfs |
|
|
546 | 0x0027e0eb cgroupfs |
|
|
547 | 0xff534d42 cifs |
|
|
548 | 0x73757245 coda |
|
|
549 | 0x012ff7b7 coh |
|
|
550 | 0x28cd3d45 cramfs |
|
|
551 | 0x453dcd28 cramfs-wend (wrong endianness) |
|
|
552 | 0x64626720 debugfs |
|
|
553 | 0x00001373 devfs |
|
|
554 | 0x00001cd1 devpts |
|
|
555 | 0x0000f15f ecryptfs |
|
|
556 | 0x00414a53 efs |
|
|
557 | 0x0000137d ext |
|
|
558 | 0x0000ef53 ext2/ext3 |
|
|
559 | 0x0000ef51 ext2 |
|
|
560 | 0x00004006 fat |
|
|
561 | 0x65735546 fuseblk |
|
|
562 | 0x65735543 fusectl |
|
|
563 | 0x0bad1dea futexfs |
|
|
564 | 0x01161970 gfs2 |
|
|
565 | 0x47504653 gpfs |
|
|
566 | 0x00004244 hfs |
|
|
567 | 0xf995e849 hpfs |
|
|
568 | 0x958458f6 hugetlbfs |
|
|
569 | 0x2bad1dea inotifyfs |
|
|
570 | 0x00009660 isofs |
|
|
571 | 0x000072b6 jffs2 |
|
|
572 | 0x3153464a jfs |
|
|
573 | 0x6b414653 k-afs |
|
|
574 | 0x0bd00bd0 lustre |
|
|
575 | 0x0000137f minix |
|
|
576 | 0x0000138f minix 30 char names |
|
|
577 | 0x00002468 minix v2 |
|
|
578 | 0x00002478 minix v2 30 char names |
|
|
579 | 0x00004d5a minix v3 |
|
|
580 | 0x19800202 mqueue |
|
|
581 | 0x00004d44 msdos |
|
|
582 | 0x0000564c novell |
|
|
583 | 0x00006969 nfs |
|
|
584 | 0x6e667364 nfsd |
|
|
585 | 0x00003434 nilfs |
|
|
586 | 0x5346544e ntfs |
|
|
587 | 0x00009fa1 openprom |
|
|
588 | 0x7461636F ocfs2 |
|
|
589 | 0x00009fa0 proc |
|
|
590 | 0x6165676c pstorefs |
|
|
591 | 0x0000002f qnx4 |
|
|
592 | 0x858458f6 ramfs |
|
|
593 | 0x52654973 reiserfs |
|
|
594 | 0x00007275 romfs |
|
|
595 | 0x67596969 rpc_pipefs |
|
|
596 | 0x73636673 securityfs |
|
|
597 | 0xf97cff8c selinux |
|
|
598 | 0x0000517b smb |
|
|
599 | 0x534f434b sockfs |
|
|
600 | 0x73717368 squashfs |
|
|
601 | 0x62656572 sysfs |
|
|
602 | 0x012ff7b6 sysv2 |
|
|
603 | 0x012ff7b5 sysv4 |
|
|
604 | 0x01021994 tmpfs |
|
|
605 | 0x15013346 udf |
|
|
606 | 0x00011954 ufs |
|
|
607 | 0x54190100 ufs byteswapped |
|
|
608 | 0x00009fa2 usbdevfs |
|
|
609 | 0x01021997 v9fs |
|
|
610 | 0xa501fcf5 vxfs |
|
|
611 | 0xabba1974 xenfs |
|
|
612 | 0x012ff7b4 xenix |
|
|
613 | 0x58465342 xfs |
|
|
614 | 0x012fd16d xia |
|
|
615 | |
| 509 | aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
616 | aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
| 510 | Works like perl's "utime" function (including the special case of |
617 | Works like perl's "utime" function (including the special case of |
| 511 | $atime and $mtime being undef). Fractional times are supported if |
618 | $atime and $mtime being undef). Fractional times are supported if |
| 512 | the underlying syscalls support them. |
619 | the underlying syscalls support them. |
| 513 | |
620 | |
| … | |
… | |
| 535 | aio_chown "path", 0, undef; |
642 | aio_chown "path", 0, undef; |
| 536 | |
643 | |
| 537 | aio_truncate $fh_or_path, $offset, $callback->($status) |
644 | aio_truncate $fh_or_path, $offset, $callback->($status) |
| 538 | Works like truncate(2) or ftruncate(2). |
645 | Works like truncate(2) or ftruncate(2). |
| 539 | |
646 | |
|
|
647 | aio_allocate $fh, $mode, $offset, $len, $callback->($status) |
|
|
648 | Allocates or frees disk space according to the $mode argument. See |
|
|
649 | the linux "fallocate" documentation for details. |
|
|
650 | |
|
|
651 | $mode can currently be 0 or "IO::AIO::FALLOC_FL_KEEP_SIZE" to |
|
|
652 | allocate space, or "IO::AIO::FALLOC_FL_PUNCH_HOLE | |
|
|
653 | IO::AIO::FALLOC_FL_KEEP_SIZE", to deallocate a file range. |
|
|
654 | |
|
|
655 | The file system block size used by "fallocate" is presumably the |
|
|
656 | "f_bsize" returned by "statvfs". |
|
|
657 | |
|
|
658 | If "fallocate" isn't available or cannot be emulated (currently no |
|
|
659 | emulation will be attempted), passes -1 and sets $! to "ENOSYS". |
|
|
660 | |
| 540 | aio_chmod $fh_or_path, $mode, $callback->($status) |
661 | aio_chmod $fh_or_path, $mode, $callback->($status) |
| 541 | Works like perl's "chmod" function. |
662 | Works like perl's "chmod" function. |
| 542 | |
663 | |
| 543 | aio_unlink $pathname, $callback->($status) |
664 | aio_unlink $pathname, $callback->($status) |
| 544 | Asynchronously unlink (delete) a file and call the callback with the |
665 | Asynchronously unlink (delete) a file and call the callback with the |
| … | |
… | |
| 570 | the callback. If an error occurs, nothing or undef gets passed to |
691 | the callback. If an error occurs, nothing or undef gets passed to |
| 571 | the callback. |
692 | the callback. |
| 572 | |
693 | |
| 573 | aio_realpath $pathname, $callback->($path) |
694 | aio_realpath $pathname, $callback->($path) |
| 574 | Asynchronously make the path absolute and resolve any symlinks in |
695 | Asynchronously make the path absolute and resolve any symlinks in |
| 575 | $path. The resulting path only consists of directories (Same as |
696 | $path. The resulting path only consists of directories (same as |
| 576 | Cwd::realpath). |
697 | Cwd::realpath). |
| 577 | |
698 | |
| 578 | This request can be used to get the absolute path of the current |
699 | This request can be used to get the absolute path of the current |
| 579 | working directory by passing it a path of . (a single dot). |
700 | working directory by passing it a path of . (a single dot). |
| 580 | |
701 | |
| 581 | aio_rename $srcpath, $dstpath, $callback->($status) |
702 | aio_rename $srcpath, $dstpath, $callback->($status) |
| 582 | Asynchronously rename the object at $srcpath to $dstpath, just as |
703 | Asynchronously rename the object at $srcpath to $dstpath, just as |
| 583 | rename(2) and call the callback with the result code. |
704 | rename(2) and call the callback with the result code. |
|
|
705 | |
|
|
706 | On systems that support the AIO::WD working directory abstraction |
|
|
707 | natively, the case "[$wd, "."]" as $srcpath is specialcased - |
|
|
708 | instead of failing, "rename" is called on the absolute path of $wd. |
| 584 | |
709 | |
| 585 | aio_mkdir $pathname, $mode, $callback->($status) |
710 | aio_mkdir $pathname, $mode, $callback->($status) |
| 586 | Asynchronously mkdir (create) a directory and call the callback with |
711 | Asynchronously mkdir (create) a directory and call the callback with |
| 587 | the result code. $mode will be modified by the umask at the time the |
712 | the result code. $mode will be modified by the umask at the time the |
| 588 | request is executed, so do not change your umask. |
713 | request is executed, so do not change your umask. |
| 589 | |
714 | |
| 590 | aio_rmdir $pathname, $callback->($status) |
715 | aio_rmdir $pathname, $callback->($status) |
| 591 | Asynchronously rmdir (delete) a directory and call the callback with |
716 | Asynchronously rmdir (delete) a directory and call the callback with |
| 592 | the result code. |
717 | the result code. |
|
|
718 | |
|
|
719 | On systems that support the AIO::WD working directory abstraction |
|
|
720 | natively, the case "[$wd, "."]" is specialcased - instead of |
|
|
721 | failing, "rmdir" is called on the absolute path of $wd. |
| 593 | |
722 | |
| 594 | aio_readdir $pathname, $callback->($entries) |
723 | aio_readdir $pathname, $callback->($entries) |
| 595 | Unlike the POSIX call of the same name, "aio_readdir" reads an |
724 | Unlike the POSIX call of the same name, "aio_readdir" reads an |
| 596 | entire directory (i.e. opendir + readdir + closedir). The entries |
725 | entire directory (i.e. opendir + readdir + closedir). The entries |
| 597 | will not be sorted, and will NOT include the "." and ".." entries. |
726 | will not be sorted, and will NOT include the "." and ".." entries. |
| … | |
… | |
| 820 | |
949 | |
| 821 | It touches (reads or writes) all memory pages in the specified range |
950 | It touches (reads or writes) all memory pages in the specified range |
| 822 | inside the scalar. All caveats and parameters are the same as for |
951 | inside the scalar. All caveats and parameters are the same as for |
| 823 | "aio_msync", above, except for flags, which must be either 0 (which |
952 | "aio_msync", above, except for flags, which must be either 0 (which |
| 824 | reads all pages and ensures they are instantiated) or |
953 | reads all pages and ensures they are instantiated) or |
| 825 | "IO::AIO::MT_MODIFY", which modifies the memory page s(by reading |
954 | "IO::AIO::MT_MODIFY", which modifies the memory pages (by reading |
| 826 | and writing an octet from it, which dirties the page). |
955 | and writing an octet from it, which dirties the page). |
| 827 | |
956 | |
| 828 | aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
957 | aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
| 829 | This is a rather advanced IO::AIO call, which works best on |
958 | This is a rather advanced IO::AIO call, which works best on |
| 830 | mmap(2)ed scalars. |
959 | mmap(2)ed scalars. |
| … | |
… | |
| 862 | |
991 | |
| 863 | Example: asynchronously lock all current and future pages into |
992 | Example: asynchronously lock all current and future pages into |
| 864 | memory. |
993 | memory. |
| 865 | |
994 | |
| 866 | aio_mlockall IO::AIO::MCL_FUTURE; |
995 | aio_mlockall IO::AIO::MCL_FUTURE; |
|
|
996 | |
|
|
997 | aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents) |
|
|
998 | Queries the extents of the given file (by calling the Linux "FIEMAP" |
|
|
999 | ioctl, see <http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for |
|
|
1000 | details). If the ioctl is not available on your OS, then this |
|
|
1001 | request will fail with "ENOSYS". |
|
|
1002 | |
|
|
1003 | $start is the starting offset to query extents for, $length is the |
|
|
1004 | size of the range to query - if it is "undef", then the whole file |
|
|
1005 | will be queried. |
|
|
1006 | |
|
|
1007 | $flags is a combination of flags ("IO::AIO::FIEMAP_FLAG_SYNC" or |
|
|
1008 | "IO::AIO::FIEMAP_FLAG_XATTR" - "IO::AIO::FIEMAP_FLAGS_COMPAT" is |
|
|
1009 | also exported), and is normally 0 or "IO::AIO::FIEMAP_FLAG_SYNC" to |
|
|
1010 | query the data portion. |
|
|
1011 | |
|
|
1012 | $count is the maximum number of extent records to return. If it is |
|
|
1013 | "undef", then IO::AIO queries all extents of the range. As a very |
|
|
1014 | special case, if it is 0, then the callback receives the number of |
|
|
1015 | extents instead of the extents themselves (which is unreliable, see |
|
|
1016 | below). |
|
|
1017 | |
|
|
1018 | If an error occurs, the callback receives no arguments. The special |
|
|
1019 | "errno" value "IO::AIO::EBADR" is available to test for flag errors. |
|
|
1020 | |
|
|
1021 | Otherwise, the callback receives an array reference with extent |
|
|
1022 | structures. Each extent structure is an array reference itself, with |
|
|
1023 | the following members: |
|
|
1024 | |
|
|
1025 | [$logical, $physical, $length, $flags] |
|
|
1026 | |
|
|
1027 | Flags is any combination of the following flag values (typically |
|
|
1028 | either 0 or "IO::AIO::FIEMAP_EXTENT_LAST" (1)): |
|
|
1029 | |
|
|
1030 | "IO::AIO::FIEMAP_EXTENT_LAST", "IO::AIO::FIEMAP_EXTENT_UNKNOWN", |
|
|
1031 | "IO::AIO::FIEMAP_EXTENT_DELALLOC", "IO::AIO::FIEMAP_EXTENT_ENCODED", |
|
|
1032 | "IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED", |
|
|
1033 | "IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED", |
|
|
1034 | "IO::AIO::FIEMAP_EXTENT_DATA_INLINE", |
|
|
1035 | "IO::AIO::FIEMAP_EXTENT_DATA_TAIL", |
|
|
1036 | "IO::AIO::FIEMAP_EXTENT_UNWRITTEN", "IO::AIO::FIEMAP_EXTENT_MERGED" |
|
|
1037 | or "IO::AIO::FIEMAP_EXTENT_SHARED". |
|
|
1038 | |
|
|
1039 | At the time of this writing (Linux 3.2), this requets is unreliable |
|
|
1040 | unless $count is "undef", as the kernel has all sorts of bugs |
|
|
1041 | preventing it to return all extents of a range for files with large |
|
|
1042 | number of extents. The code works around all these issues if $count |
|
|
1043 | is undef. |
| 867 | |
1044 | |
| 868 | aio_group $callback->(...) |
1045 | aio_group $callback->(...) |
| 869 | This is a very special aio request: Instead of doing something, it |
1046 | This is a very special aio request: Instead of doing something, it |
| 870 | is a container for other aio requests, which is useful if you want |
1047 | is a container for other aio requests, which is useful if you want |
| 871 | to bundle many requests into a single, composite, request with a |
1048 | to bundle many requests into a single, composite, request with a |
| … | |
… | |
| 951 | aio_stat [$etcdir, "passwd"], sub { |
1128 | aio_stat [$etcdir, "passwd"], sub { |
| 952 | # yay |
1129 | # yay |
| 953 | }; |
1130 | }; |
| 954 | }; |
1131 | }; |
| 955 | |
1132 | |
| 956 | That "aio_wd" is a request and not a normal function shows that creating |
1133 | The fact that "aio_wd" is a request and not a normal function shows that |
| 957 | an IO::AIO::WD object is itself a potentially blocking operation, which |
1134 | creating an IO::AIO::WD object is itself a potentially blocking |
| 958 | is why it is done asynchronously. |
1135 | operation, which is why it is done asynchronously. |
| 959 | |
1136 | |
| 960 | To stat the directory obtained with "aio_wd" above, one could write |
1137 | To stat the directory obtained with "aio_wd" above, one could write |
| 961 | either of the following three request calls: |
1138 | either of the following three request calls: |
| 962 | |
1139 | |
| 963 | aio_lstat "/etc" , sub { ... # pathname as normal string |
1140 | aio_lstat "/etc" , sub { ... # pathname as normal string |
| … | |
… | |
| 983 | will still point to the original directory. Most functions accepting a |
1160 | will still point to the original directory. Most functions accepting a |
| 984 | pathname will use the directory fd on newer systems, and the string on |
1161 | pathname will use the directory fd on newer systems, and the string on |
| 985 | older systems. Some functions (such as realpath) will always rely on the |
1162 | older systems. Some functions (such as realpath) will always rely on the |
| 986 | string form of the pathname. |
1163 | string form of the pathname. |
| 987 | |
1164 | |
| 988 | So this fucntionality is mainly useful to get some protection against |
1165 | So this functionality is mainly useful to get some protection against |
| 989 | "chdir", to easily get an absolute path out of a relative path for |
1166 | "chdir", to easily get an absolute path out of a relative path for |
| 990 | future reference, and to speed up doing many operations in the same |
1167 | future reference, and to speed up doing many operations in the same |
| 991 | directory (e.g. when stat'ing all files in a directory). |
1168 | directory (e.g. when stat'ing all files in a directory). |
| 992 | |
1169 | |
| 993 | The following functions implement this working directory abstraction: |
1170 | The following functions implement this working directory abstraction: |
| … | |
… | |
| 1003 | Since passing "undef" as working directory component of a pathname |
1180 | Since passing "undef" as working directory component of a pathname |
| 1004 | fails the request with "ENOENT", there is often no need for error |
1181 | fails the request with "ENOENT", there is often no need for error |
| 1005 | checking in the "aio_wd" callback, as future requests using the |
1182 | checking in the "aio_wd" callback, as future requests using the |
| 1006 | value will fail in the expected way. |
1183 | value will fail in the expected way. |
| 1007 | |
1184 | |
| 1008 | If this call isn't available because your OS lacks it or it couldn't |
|
|
| 1009 | be detected, it will be emulated by calling "fsync" instead. |
|
|
| 1010 | |
|
|
| 1011 | IO::AIO::CWD |
1185 | IO::AIO::CWD |
| 1012 | This is a compiletime constant (object) that represents the process |
1186 | This is a compiletime constant (object) that represents the process |
| 1013 | current working directory. |
1187 | current working directory. |
| 1014 | |
1188 | |
| 1015 | Specifying this object as working directory object for a pathname is |
1189 | Specifying this object as working directory object for a pathname is |
| 1016 | as if the pathname would be specified directly, without a directory |
1190 | as if the pathname would be specified directly, without a directory |
| 1017 | object, e.g., these calls are functionally identical: |
1191 | object. For example, these calls are functionally identical: |
| 1018 | |
1192 | |
| 1019 | aio_stat "somefile", sub { ... }; |
1193 | aio_stat "somefile", sub { ... }; |
| 1020 | aio_stat [IO::AIO::CWD, "somefile"], sub { ... }; |
1194 | aio_stat [IO::AIO::CWD, "somefile"], sub { ... }; |
|
|
1195 | |
|
|
1196 | To recover the path associated with an IO::AIO::WD object, you can use |
|
|
1197 | "aio_realpath": |
|
|
1198 | |
|
|
1199 | aio_realpath $wd, sub { |
|
|
1200 | warn "path is $_[0]\n"; |
|
|
1201 | }; |
|
|
1202 | |
|
|
1203 | Currently, "aio_statvfs" always, and "aio_rename" and "aio_rmdir" |
|
|
1204 | sometimes, fall back to using an absolue path. |
| 1021 | |
1205 | |
| 1022 | IO::AIO::REQ CLASS |
1206 | IO::AIO::REQ CLASS |
| 1023 | All non-aggregate "aio_*" functions return an object of this class when |
1207 | All non-aggregate "aio_*" functions return an object of this class when |
| 1024 | called in non-void context. |
1208 | called in non-void context. |
| 1025 | |
1209 | |
| … | |
… | |
| 1177 | results. |
1361 | results. |
| 1178 | |
1362 | |
| 1179 | See "poll_cb" for an example. |
1363 | See "poll_cb" for an example. |
| 1180 | |
1364 | |
| 1181 | IO::AIO::poll_cb |
1365 | IO::AIO::poll_cb |
| 1182 | Process some outstanding events on the result pipe. You have to call |
1366 | Process some requests that have reached the result phase (i.e. they |
|
|
1367 | have been executed but the results are not yet reported). You have |
|
|
1368 | to call this "regularly" to finish outstanding requests. |
|
|
1369 | |
| 1183 | this regularly. Returns 0 if all events could be processed (or there |
1370 | Returns 0 if all events could be processed (or there were no events |
| 1184 | were no events to process), or -1 if it returned earlier for |
1371 | to process), or -1 if it returned earlier for whatever reason. |
| 1185 | whatever reason. Returns immediately when no events are outstanding. |
1372 | Returns immediately when no events are outstanding. The amount of |
| 1186 | The amount of events processed depends on the settings of |
1373 | events processed depends on the settings of "IO::AIO::max_poll_req", |
| 1187 | "IO::AIO::max_poll_req" and "IO::AIO::max_poll_time". |
1374 | "IO::AIO::max_poll_time" and "IO::AIO::max_outstanding". |
| 1188 | |
1375 | |
| 1189 | If not all requests were processed for whatever reason, the |
1376 | If not all requests were processed for whatever reason, the poll |
| 1190 | filehandle will still be ready when "poll_cb" returns, so normally |
1377 | file descriptor will still be ready when "poll_cb" returns, so |
| 1191 | you don't have to do anything special to have it called later. |
1378 | normally you don't have to do anything special to have it called |
|
|
1379 | later. |
| 1192 | |
1380 | |
| 1193 | Apart from calling "IO::AIO::poll_cb" when the event filehandle |
1381 | Apart from calling "IO::AIO::poll_cb" when the event filehandle |
| 1194 | becomes ready, it can be beneficial to call this function from loops |
1382 | becomes ready, it can be beneficial to call this function from loops |
| 1195 | which submit a lot of requests, to make sure the results get |
1383 | which submit a lot of requests, to make sure the results get |
| 1196 | processed when they become available and not just when the loop is |
1384 | processed when they become available and not just when the loop is |
| … | |
… | |
| 1204 | Event->io (fd => IO::AIO::poll_fileno, |
1392 | Event->io (fd => IO::AIO::poll_fileno, |
| 1205 | poll => 'r', async => 1, |
1393 | poll => 'r', async => 1, |
| 1206 | cb => \&IO::AIO::poll_cb); |
1394 | cb => \&IO::AIO::poll_cb); |
| 1207 | |
1395 | |
| 1208 | IO::AIO::poll_wait |
1396 | IO::AIO::poll_wait |
| 1209 | If there are any outstanding requests and none of them in the result |
1397 | Wait until either at least one request is in the result phase or no |
| 1210 | phase, wait till the result filehandle becomes ready for reading |
1398 | requests are outstanding anymore. |
| 1211 | (simply does a "select" on the filehandle. This is useful if you |
1399 | |
| 1212 | want to synchronously wait for some requests to finish). |
1400 | This is useful if you want to synchronously wait for some requests |
|
|
1401 | to become ready, without actually handling them. |
| 1213 | |
1402 | |
| 1214 | See "nreqs" for an example. |
1403 | See "nreqs" for an example. |
| 1215 | |
1404 | |
| 1216 | IO::AIO::poll |
1405 | IO::AIO::poll |
| 1217 | Waits until some requests have been handled. |
1406 | Waits until some requests have been handled. |
| … | |
… | |
| 1329 | |
1518 | |
| 1330 | This is a very bad function to use in interactive programs because |
1519 | This is a very bad function to use in interactive programs because |
| 1331 | it blocks, and a bad way to reduce concurrency because it is |
1520 | it blocks, and a bad way to reduce concurrency because it is |
| 1332 | inexact: Better use an "aio_group" together with a feed callback. |
1521 | inexact: Better use an "aio_group" together with a feed callback. |
| 1333 | |
1522 | |
| 1334 | It's main use is in scripts without an event loop - when you want to |
1523 | Its main use is in scripts without an event loop - when you want to |
| 1335 | stat a lot of files, you can write somehting like this: |
1524 | stat a lot of files, you can write somehting like this: |
| 1336 | |
1525 | |
| 1337 | IO::AIO::max_outstanding 32; |
1526 | IO::AIO::max_outstanding 32; |
| 1338 | |
1527 | |
| 1339 | for my $path (...) { |
1528 | for my $path (...) { |
| … | |
… | |
| 1370 | IO::AIO::npending |
1559 | IO::AIO::npending |
| 1371 | Returns the number of requests currently in the pending state |
1560 | Returns the number of requests currently in the pending state |
| 1372 | (executed, but not yet processed by poll_cb). |
1561 | (executed, but not yet processed by poll_cb). |
| 1373 | |
1562 | |
| 1374 | MISCELLANEOUS FUNCTIONS |
1563 | MISCELLANEOUS FUNCTIONS |
| 1375 | IO::AIO implements some functions that might be useful, but are not |
1564 | IO::AIO implements some functions that are useful when you want to use |
| 1376 | asynchronous. |
1565 | some "Advanced I/O" function not available to in Perl, without going the |
|
|
1566 | "Asynchronous I/O" route. Many of these have an asynchronous "aio_*" |
|
|
1567 | counterpart. |
| 1377 | |
1568 | |
| 1378 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
1569 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
| 1379 | Calls the "eio_sendfile_sync" function, which is like |
1570 | Calls the "eio_sendfile_sync" function, which is like |
| 1380 | "aio_sendfile", but is blocking (this makes most sense if you know |
1571 | "aio_sendfile", but is blocking (this makes most sense if you know |
| 1381 | the input data is likely cached already and the output filehandle is |
1572 | the input data is likely cached already and the output filehandle is |
| … | |
… | |
| 1412 | On systems that do not implement "mprotect", this function returns |
1603 | On systems that do not implement "mprotect", this function returns |
| 1413 | ENOSYS, otherwise the return value of "mprotect". |
1604 | ENOSYS, otherwise the return value of "mprotect". |
| 1414 | |
1605 | |
| 1415 | IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
1606 | IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
| 1416 | Memory-maps a file (or anonymous memory range) and attaches it to |
1607 | Memory-maps a file (or anonymous memory range) and attaches it to |
| 1417 | the given $scalar, which will act like a string scalar. |
1608 | the given $scalar, which will act like a string scalar. Returns true |
|
|
1609 | on success, and false otherwise. |
| 1418 | |
1610 | |
| 1419 | The only operations allowed on the scalar are "substr"/"vec" that |
1611 | The only operations allowed on the scalar are "substr"/"vec" that |
| 1420 | don't change the string length, and most read-only operations such |
1612 | don't change the string length, and most read-only operations such |
| 1421 | as copying it or searching it with regexes and so on. |
1613 | as copying it or searching it with regexes and so on. |
| 1422 | |
1614 | |
| … | |
… | |
| 1472 | IO::AIO::munlockall |
1664 | IO::AIO::munlockall |
| 1473 | Calls the "munlockall" function. |
1665 | Calls the "munlockall" function. |
| 1474 | |
1666 | |
| 1475 | On systems that do not implement "munlockall", this function returns |
1667 | On systems that do not implement "munlockall", this function returns |
| 1476 | ENOSYS, otherwise the return value of "munlockall". |
1668 | ENOSYS, otherwise the return value of "munlockall". |
|
|
1669 | |
|
|
1670 | IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags |
|
|
1671 | Calls the GNU/Linux splice(2) syscall, if available. If $r_off or |
|
|
1672 | $w_off are "undef", then "NULL" is passed for these, otherwise they |
|
|
1673 | should be the file offset. |
|
|
1674 | |
|
|
1675 | $r_fh and $w_fh should not refer to the same file, as splice might |
|
|
1676 | silently corrupt the data in this case. |
|
|
1677 | |
|
|
1678 | The following symbol flag values are available: |
|
|
1679 | "IO::AIO::SPLICE_F_MOVE", "IO::AIO::SPLICE_F_NONBLOCK", |
|
|
1680 | "IO::AIO::SPLICE_F_MORE" and "IO::AIO::SPLICE_F_GIFT". |
|
|
1681 | |
|
|
1682 | See the splice(2) manpage for details. |
|
|
1683 | |
|
|
1684 | IO::AIO::tee $r_fh, $w_fh, $length, $flags |
|
|
1685 | Calls the GNU/Linux tee(2) syscall, see its manpage and the |
|
|
1686 | description for "IO::AIO::splice" above for details. |
|
|
1687 | |
|
|
1688 | $actual_size = IO::AIO::pipesize $r_fh[, $new_size] |
|
|
1689 | Attempts to query or change the pipe buffer size. Obviously works |
|
|
1690 | only on pipes, and currently works only on GNU/Linux systems, and |
|
|
1691 | fails with -1/"ENOSYS" everywhere else. If anybody knows how to |
|
|
1692 | influence pipe buffer size on other systems, drop me a note. |
| 1477 | |
1693 | |
| 1478 | EVENT LOOP INTEGRATION |
1694 | EVENT LOOP INTEGRATION |
| 1479 | It is recommended to use AnyEvent::AIO to integrate IO::AIO |
1695 | It is recommended to use AnyEvent::AIO to integrate IO::AIO |
| 1480 | automatically into many event loops: |
1696 | automatically into many event loops: |
| 1481 | |
1697 | |
