… | |
… | |
175 | All the "aio_*" calls are more or less thin wrappers around the syscall |
175 | All the "aio_*" calls are more or less thin wrappers around the syscall |
176 | with the same name (sans "aio_"). The arguments are similar or |
176 | with the same name (sans "aio_"). The arguments are similar or |
177 | identical, and they all accept an additional (and optional) $callback |
177 | identical, and they all accept an additional (and optional) $callback |
178 | argument which must be a code reference. This code reference will get |
178 | argument which must be a code reference. This code reference will get |
179 | called with the syscall return code (e.g. most syscalls return -1 on |
179 | called with the syscall return code (e.g. most syscalls return -1 on |
180 | error, unlike perl, which usually delivers "false") as it's sole |
180 | error, unlike perl, which usually delivers "false") as its sole argument |
181 | argument when the given syscall has been executed asynchronously. |
181 | after the given syscall has been executed asynchronously. |
182 | |
182 | |
183 | All functions expecting a filehandle keep a copy of the filehandle |
183 | All functions expecting a filehandle keep a copy of the filehandle |
184 | internally until the request has finished. |
184 | internally until the request has finished. |
185 | |
185 | |
186 | All functions return request objects of type IO::AIO::REQ that allow |
186 | All functions return request objects of type IO::AIO::REQ that allow |
… | |
… | |
199 | the user environment, d) use Glib::filename_from_unicode on unicode |
199 | the user environment, d) use Glib::filename_from_unicode on unicode |
200 | filenames or e) use something else to ensure your scalar has the correct |
200 | filenames or e) use something else to ensure your scalar has the correct |
201 | contents. |
201 | contents. |
202 | |
202 | |
203 | This works, btw. independent of the internal UTF-8 bit, which IO::AIO |
203 | This works, btw. independent of the internal UTF-8 bit, which IO::AIO |
204 | handles correctly wether it is set or not. |
204 | handles correctly whether it is set or not. |
205 | |
205 | |
206 | $prev_pri = aioreq_pri [$pri] |
206 | $prev_pri = aioreq_pri [$pri] |
207 | Returns the priority value that would be used for the next request |
207 | Returns the priority value that would be used for the next request |
208 | and, if $pri is given, sets the priority for the next aio request. |
208 | and, if $pri is given, sets the priority for the next aio request. |
209 | |
209 | |
… | |
… | |
275 | Or in other words: the file descriptor will be closed, but it will |
275 | Or in other words: the file descriptor will be closed, but it will |
276 | not be free for reuse until the perl filehandle is closed. |
276 | not be free for reuse until the perl filehandle is closed. |
277 | |
277 | |
278 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
278 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
279 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
279 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
280 | Reads or writes $length bytes from the specified $fh and $offset |
280 | Reads or writes $length bytes from or to the specified $fh and |
281 | into the scalar given by $data and offset $dataoffset and calls the |
281 | $offset into the scalar given by $data and offset $dataoffset and |
282 | callback without the actual number of bytes read (or -1 on error, |
282 | calls the callback without the actual number of bytes read (or -1 on |
283 | just like the syscall). |
283 | error, just like the syscall). |
|
|
284 | |
|
|
285 | "aio_read" will, like "sysread", shrink or grow the $data scalar to |
|
|
286 | offset plus the actual number of bytes read. |
284 | |
287 | |
285 | If $offset is undefined, then the current file descriptor offset |
288 | If $offset is undefined, then the current file descriptor offset |
286 | will be used (and updated), otherwise the file descriptor offset |
289 | will be used (and updated), otherwise the file descriptor offset |
287 | will not be changed by these calls. |
290 | will not be changed by these calls. |
288 | |
291 | |
… | |
… | |
439 | aio_readdir $pathname, $callback->($entries) |
442 | aio_readdir $pathname, $callback->($entries) |
440 | Unlike the POSIX call of the same name, "aio_readdir" reads an |
443 | Unlike the POSIX call of the same name, "aio_readdir" reads an |
441 | entire directory (i.e. opendir + readdir + closedir). The entries |
444 | entire directory (i.e. opendir + readdir + closedir). The entries |
442 | will not be sorted, and will NOT include the "." and ".." entries. |
445 | will not be sorted, and will NOT include the "." and ".." entries. |
443 | |
446 | |
444 | The callback a single argument which is either "undef" or an |
447 | The callback is passed a single argument which is either "undef" or |
445 | array-ref with the filenames. |
448 | an array-ref with the filenames. |
|
|
449 | |
|
|
450 | aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
|
|
451 | Quite similar to "aio_readdir", but the $flags argument allows to |
|
|
452 | tune behaviour and output format. In case of an error, $entries will |
|
|
453 | be "undef". |
|
|
454 | |
|
|
455 | The flags are a combination of the following constants, ORed |
|
|
456 | together (the flags will also be passed to the callback, possibly |
|
|
457 | modified): |
|
|
458 | |
|
|
459 | IO::AIO::READDIR_DENTS |
|
|
460 | When this flag is off, then the callback gets an arrayref with |
|
|
461 | of names only (as with "aio_readdir"), otherwise it gets an |
|
|
462 | arrayref with "[$name, $type, $inode]" arrayrefs, each |
|
|
463 | describing a single directory entry in more detail. |
|
|
464 | |
|
|
465 | $name is the name of the entry. |
|
|
466 | |
|
|
467 | $type is one of the "IO::AIO::DT_xxx" constants: |
|
|
468 | |
|
|
469 | "IO::AIO::DT_UNKNOWN", "IO::AIO::DT_FIFO", "IO::AIO::DT_CHR", |
|
|
470 | "IO::AIO::DT_DIR", "IO::AIO::DT_BLK", "IO::AIO::DT_REG", |
|
|
471 | "IO::AIO::DT_LNK", "IO::AIO::DT_SOCK", "IO::AIO::DT_WHT". |
|
|
472 | |
|
|
473 | "IO::AIO::DT_UNKNOWN" means just that: readdir does not know. If |
|
|
474 | you need to know, you have to run stat yourself. Also, for speed |
|
|
475 | reasons, the $type scalars are read-only: you can not modify |
|
|
476 | them. |
|
|
477 | |
|
|
478 | $inode is the inode number (which might not be exact on systems |
|
|
479 | with 64 bit inode numbers and 32 bit perls). On systems that do |
|
|
480 | not deliver the inode information, this will always be zero. |
|
|
481 | |
|
|
482 | IO::AIO::READDIR_DIRS_FIRST |
|
|
483 | When this flag is set, then the names will be returned in an |
|
|
484 | order where likely directories come first. This is useful when |
|
|
485 | you need to quickly find directories, or you want to find all |
|
|
486 | directories while avoiding to stat() each entry. |
|
|
487 | |
|
|
488 | If the system returns type information in readdir, then this is |
|
|
489 | used to find directories directly. Otherwise, likely directories |
|
|
490 | are files beginning with ".", or otherwise files with no dots, |
|
|
491 | of which files with short names are tried first. |
|
|
492 | |
|
|
493 | IO::AIO::READDIR_STAT_ORDER |
|
|
494 | When this flag is set, then the names will be returned in an |
|
|
495 | order suitable for stat()'ing each one. That is, when you plan |
|
|
496 | to stat() all files in the given directory, then the returned |
|
|
497 | order will likely be fastest. |
|
|
498 | |
|
|
499 | If both this flag and "IO::AIO::READDIR_DIRS_FIRST" are |
|
|
500 | specified, then the likely dirs come first, resulting in a less |
|
|
501 | optimal stat order. |
|
|
502 | |
|
|
503 | IO::AIO::READDIR_FOUND_UNKNOWN |
|
|
504 | This flag should not be set when calling "aio_readdirx". |
|
|
505 | Instead, it is being set by "aio_readdirx", when any of the |
|
|
506 | $type's found were "IO::AIO::DT_UNKNOWN". The absense of this |
|
|
507 | flag therefore indicates that all $type's are known, which can |
|
|
508 | be used to speed up some algorithms. |
446 | |
509 | |
447 | aio_load $path, $data, $callback->($status) |
510 | aio_load $path, $data, $callback->($status) |
448 | This is a composite request that tries to fully load the given file |
511 | This is a composite request that tries to fully load the given file |
449 | into memory. Status is the same as with aio_read. |
512 | into memory. Status is the same as with aio_read. |
450 | |
513 | |
451 | aio_copy $srcpath, $dstpath, $callback->($status) |
514 | aio_copy $srcpath, $dstpath, $callback->($status) |
452 | Try to copy the *file* (directories not supported as either source |
515 | Try to copy the *file* (directories not supported as either source |
453 | or destination) from $srcpath to $dstpath and call the callback with |
516 | or destination) from $srcpath to $dstpath and call the callback with |
454 | the 0 (error) or -1 ok. |
517 | the 0 (error) or -1 ok. |
455 | |
518 | |
456 | This is a composite request that it creates the destination file |
519 | This is a composite request that creates the destination file with |
457 | with mode 0200 and copies the contents of the source file into it |
520 | mode 0200 and copies the contents of the source file into it using |
458 | using "aio_sendfile", followed by restoring atime, mtime, access |
521 | "aio_sendfile", followed by restoring atime, mtime, access mode and |
459 | mode and uid/gid, in that order. |
522 | uid/gid, in that order. |
460 | |
523 | |
461 | If an error occurs, the partial destination file will be unlinked, |
524 | If an error occurs, the partial destination file will be unlinked, |
462 | if possible, except when setting atime, mtime, access mode and |
525 | if possible, except when setting atime, mtime, access mode and |
463 | uid/gid, where errors are being ignored. |
526 | uid/gid, where errors are being ignored. |
464 | |
527 | |
465 | aio_move $srcpath, $dstpath, $callback->($status) |
528 | aio_move $srcpath, $dstpath, $callback->($status) |
466 | Try to move the *file* (directories not supported as either source |
529 | Try to move the *file* (directories not supported as either source |
467 | or destination) from $srcpath to $dstpath and call the callback with |
530 | or destination) from $srcpath to $dstpath and call the callback with |
468 | the 0 (error) or -1 ok. |
531 | the 0 (error) or -1 ok. |
469 | |
532 | |
470 | This is a composite request that tries to rename(2) the file first. |
533 | This is a composite request that tries to rename(2) the file first; |
471 | If rename files with "EXDEV", it copies the file with "aio_copy" |
534 | if rename fails with "EXDEV", it copies the file with "aio_copy" |
472 | and, if that is successful, unlinking the $srcpath. |
535 | and, if that is successful, unlinks the $srcpath. |
473 | |
536 | |
474 | aio_scandir $path, $maxreq, $callback->($dirs, $nondirs) |
537 | aio_scandir $path, $maxreq, $callback->($dirs, $nondirs) |
475 | Scans a directory (similar to "aio_readdir") but additionally tries |
538 | Scans a directory (similar to "aio_readdir") but additionally tries |
476 | to efficiently separate the entries of directory $path into two sets |
539 | to efficiently separate the entries of directory $path into two sets |
477 | of names, directories you can recurse into (directories), and ones |
540 | of names, directories you can recurse into (directories), and ones |
… | |
… | |
497 | Implementation notes. |
560 | Implementation notes. |
498 | |
561 | |
499 | The "aio_readdir" cannot be avoided, but "stat()"'ing every entry |
562 | The "aio_readdir" cannot be avoided, but "stat()"'ing every entry |
500 | can. |
563 | can. |
501 | |
564 | |
|
|
565 | If readdir returns file type information, then this is used directly |
|
|
566 | to find directories. |
|
|
567 | |
502 | After reading the directory, the modification time, size etc. of the |
568 | Otherwise, after reading the directory, the modification time, size |
503 | directory before and after the readdir is checked, and if they match |
569 | etc. of the directory before and after the readdir is checked, and |
504 | (and isn't the current time), the link count will be used to decide |
570 | if they match (and isn't the current time), the link count will be |
505 | how many entries are directories (if >= 2). Otherwise, no knowledge |
571 | used to decide how many entries are directories (if >= 2). |
506 | of the number of subdirectories will be assumed. |
572 | Otherwise, no knowledge of the number of subdirectories will be |
|
|
573 | assumed. |
507 | |
574 | |
508 | Then entries will be sorted into likely directories (everything |
575 | Then entries will be sorted into likely directories a non-initial |
509 | without a non-initial dot currently) and likely non-directories |
576 | dot currently) and likely non-directories (see "aio_readdirx"). Then |
510 | (everything else). Then every entry plus an appended "/." will be |
577 | every entry plus an appended "/." will be "stat"'ed, likely |
511 | "stat"'ed, likely directories first. If that succeeds, it assumes |
578 | directories first, in order of their inode numbers. If that |
512 | that the entry is a directory or a symlink to directory (which will |
579 | succeeds, it assumes that the entry is a directory or a symlink to |
513 | be checked seperately). This is often faster than stat'ing the entry |
580 | directory (which will be checked seperately). This is often faster |
514 | itself because filesystems might detect the type of the entry |
581 | than stat'ing the entry itself because filesystems might detect the |
515 | without reading the inode data (e.g. ext2fs filetype feature). |
582 | type of the entry without reading the inode data (e.g. ext2fs |
|
|
583 | filetype feature), even on systems that cannot return the filetype |
|
|
584 | information on readdir. |
516 | |
585 | |
517 | If the known number of directories (link count - 2) has been |
586 | If the known number of directories (link count - 2) has been |
518 | reached, the rest of the entries is assumed to be non-directories. |
587 | reached, the rest of the entries is assumed to be non-directories. |
519 | |
588 | |
520 | This only works with certainty on POSIX (= UNIX) filesystems, which |
589 | This only works with certainty on POSIX (= UNIX) filesystems, which |
… | |
… | |
542 | callback with the fdatasync result code. |
611 | callback with the fdatasync result code. |
543 | |
612 | |
544 | If this call isn't available because your OS lacks it or it couldn't |
613 | If this call isn't available because your OS lacks it or it couldn't |
545 | be detected, it will be emulated by calling "fsync" instead. |
614 | be detected, it will be emulated by calling "fsync" instead. |
546 | |
615 | |
|
|
616 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
|
|
617 | Sync the data portion of the file specified by $offset and $length |
|
|
618 | to disk (but NOT the metadata), by calling the Linux-specific |
|
|
619 | sync_file_range call. If sync_file_range is not available or it |
|
|
620 | returns ENOSYS, then fdatasync or fsync is being substituted. |
|
|
621 | |
|
|
622 | $flags can be a combination of |
|
|
623 | "IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE", |
|
|
624 | "IO::AIO::SYNC_FILE_RANGE_WRITE" and |
|
|
625 | "IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER": refer to the sync_file_range |
|
|
626 | manpage for details. |
|
|
627 | |
547 | aio_pathsync $path, $callback->($status) |
628 | aio_pathsync $path, $callback->($status) |
548 | This request tries to open, fsync and close the given path. This is |
629 | This request tries to open, fsync and close the given path. This is |
549 | a composite request intended tosync directories after directory |
630 | a composite request intended to sync directories after directory |
550 | operations (E.g. rename). This might not work on all operating |
631 | operations (E.g. rename). This might not work on all operating |
551 | systems or have any specific effect, but usually it makes sure that |
632 | systems or have any specific effect, but usually it makes sure that |
552 | directory changes get written to disc. It works for anything that |
633 | directory changes get written to disc. It works for anything that |
553 | can be opened for read-only, not just directories. |
634 | can be opened for read-only, not just directories. |
554 | |
635 | |
… | |
… | |
658 | Their lifetime, simplified, looks like this: when they are empty, they |
739 | Their lifetime, simplified, looks like this: when they are empty, they |
659 | will finish very quickly. If they contain only requests that are in the |
740 | will finish very quickly. If they contain only requests that are in the |
660 | "done" state, they will also finish. Otherwise they will continue to |
741 | "done" state, they will also finish. Otherwise they will continue to |
661 | exist. |
742 | exist. |
662 | |
743 | |
663 | That means after creating a group you have some time to add requests. |
744 | That means after creating a group you have some time to add requests |
664 | And in the callbacks of those requests, you can add further requests to |
745 | (precisely before the callback has been invoked, which is only done |
665 | the group. And only when all those requests have finished will the the |
746 | within the "poll_cb"). And in the callbacks of those requests, you can |
666 | group itself finish. |
747 | add further requests to the group. And only when all those requests have |
|
|
748 | finished will the the group itself finish. |
667 | |
749 | |
668 | add $grp ... |
750 | add $grp ... |
669 | $grp->add (...) |
751 | $grp->add (...) |
670 | Add one or more requests to the group. Any type of IO::AIO::REQ can |
752 | Add one or more requests to the group. Any type of IO::AIO::REQ can |
671 | be added, including other groups, as long as you do not create |
753 | be added, including other groups, as long as you do not create |
… | |
… | |
714 | does not impose any limits). |
796 | does not impose any limits). |
715 | |
797 | |
716 | If the feed does not queue more requests when called, it will be |
798 | If the feed does not queue more requests when called, it will be |
717 | automatically removed from the group. |
799 | automatically removed from the group. |
718 | |
800 | |
719 | If the feed limit is 0, it will be set to 2 automatically. |
801 | If the feed limit is 0 when this method is called, it will be set to |
|
|
802 | 2 automatically. |
720 | |
803 | |
721 | Example: |
804 | Example: |
722 | |
805 | |
723 | # stat all files in @files, but only ever use four aio requests concurrently: |
806 | # stat all files in @files, but only ever use four aio requests concurrently: |
724 | |
807 | |
… | |
… | |
734 | limit $grp $num |
817 | limit $grp $num |
735 | Sets the feeder limit for the group: The feeder will be called |
818 | Sets the feeder limit for the group: The feeder will be called |
736 | whenever the group contains less than this many requests. |
819 | whenever the group contains less than this many requests. |
737 | |
820 | |
738 | Setting the limit to 0 will pause the feeding process. |
821 | Setting the limit to 0 will pause the feeding process. |
|
|
822 | |
|
|
823 | The default value for the limit is 0, but note that setting a feeder |
|
|
824 | automatically bumps it up to 2. |
739 | |
825 | |
740 | SUPPORT FUNCTIONS |
826 | SUPPORT FUNCTIONS |
741 | EVENT PROCESSING AND EVENT LOOP INTEGRATION |
827 | EVENT PROCESSING AND EVENT LOOP INTEGRATION |
742 | $fileno = IO::AIO::poll_fileno |
828 | $fileno = IO::AIO::poll_fileno |
743 | Return the *request result pipe file descriptor*. This filehandle |
829 | Return the *request result pipe file descriptor*. This filehandle |