| … | |
… | |
| 442 | aio_readdir $pathname, $callback->($entries) |
442 | aio_readdir $pathname, $callback->($entries) |
| 443 | 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 |
| 444 | entire directory (i.e. opendir + readdir + closedir). The entries |
444 | entire directory (i.e. opendir + readdir + closedir). The entries |
| 445 | will not be sorted, and will NOT include the "." and ".." entries. |
445 | will not be sorted, and will NOT include the "." and ".." entries. |
| 446 | |
446 | |
| 447 | The callback a single argument which is either "undef" or an |
447 | The callback is passed a single argument which is either "undef" or |
| 448 | array-ref with the filenames. |
448 | an array-ref with the filenames. |
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449 | |
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450 | aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
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451 | Quite similar to "aio_readdir", but the $flags argument allows to |
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452 | tune behaviour and output format. In case of an error, $entries will |
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453 | be "undef". |
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454 | |
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455 | The flags are a combination of the following constants, ORed |
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456 | together (the flags will also be passed to the callback, possibly |
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457 | modified): |
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458 | |
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459 | IO::AIO::READDIR_DENTS |
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460 | When this flag is off, then the callback gets an arrayref with |
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461 | of names only (as with "aio_readdir"), otherwise it gets an |
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462 | arrayref with "[$name, $type, $inode]" arrayrefs, each |
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463 | describing a single directory entry in more detail. |
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464 | |
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465 | $name is the name of the entry. |
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466 | |
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467 | $type is one of the "IO::AIO::DT_xxx" constants: |
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468 | |
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469 | "IO::AIO::DT_UNKNOWN", "IO::AIO::DT_FIFO", "IO::AIO::DT_CHR", |
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470 | "IO::AIO::DT_DIR", "IO::AIO::DT_BLK", "IO::AIO::DT_REG", |
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471 | "IO::AIO::DT_LNK", "IO::AIO::DT_SOCK", "IO::AIO::DT_WHT". |
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472 | |
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473 | "IO::AIO::DT_UNKNOWN" means just that: readdir does not know. If |
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474 | you need to know, you have to run stat yourself. Also, for speed |
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475 | reasons, the $type scalars are read-only: you can not modify |
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476 | them. |
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477 | |
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478 | $inode is the inode number (which might not be exact on systems |
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479 | with 64 bit inode numbers and 32 bit perls). On systems that do |
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480 | not deliver the inode information, this will always be zero. |
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481 | |
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482 | IO::AIO::READDIR_DIRS_FIRST |
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483 | When this flag is set, then the names will be returned in an |
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484 | order where likely directories come first. This is useful when |
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485 | you need to quickly find directories, or you want to find all |
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486 | directories while avoiding to stat() each entry. |
|
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487 | |
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488 | If the system returns type information in readdir, then this is |
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489 | used to find directories directly. Otherwise, likely directories |
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490 | are files beginning with ".", or otherwise files with no dots, |
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491 | of which files with short names are tried first. |
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492 | |
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493 | IO::AIO::READDIR_STAT_ORDER |
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494 | When this flag is set, then the names will be returned in an |
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495 | order suitable for stat()'ing each one. That is, when you plan |
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496 | to stat() all files in the given directory, then the returned |
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497 | order will likely be fastest. |
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498 | |
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499 | If both this flag and "IO::AIO::READDIR_DIRS_FIRST" are |
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500 | specified, then the likely dirs come first, resulting in a less |
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501 | optimal stat order. |
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502 | |
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503 | IO::AIO::READDIR_FOUND_UNKNOWN |
|
|
504 | This flag should not be set when calling "aio_readdirx". |
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505 | Instead, it is being set by "aio_readdirx", when any of the |
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506 | $type's found were "IO::AIO::DT_UNKNOWN". The absense of this |
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507 | flag therefore indicates that all $type's are known, which can |
|
|
508 | be used to speed up some algorithms. |
| 449 | |
509 | |
| 450 | aio_load $path, $data, $callback->($status) |
510 | aio_load $path, $data, $callback->($status) |
| 451 | 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 |
| 452 | into memory. Status is the same as with aio_read. |
512 | into memory. Status is the same as with aio_read. |
| 453 | |
513 | |
| … | |
… | |
| 500 | Implementation notes. |
560 | Implementation notes. |
| 501 | |
561 | |
| 502 | The "aio_readdir" cannot be avoided, but "stat()"'ing every entry |
562 | The "aio_readdir" cannot be avoided, but "stat()"'ing every entry |
| 503 | can. |
563 | can. |
| 504 | |
564 | |
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565 | If readdir returns file type information, then this is used directly |
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566 | to find directories. |
|
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567 | |
| 505 | After reading the directory, the modification time, size etc. of the |
568 | Otherwise, after reading the directory, the modification time, size |
| 506 | 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 |
| 507 | (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 |
| 508 | how many entries are directories (if >= 2). Otherwise, no knowledge |
571 | used to decide how many entries are directories (if >= 2). |
| 509 | of the number of subdirectories will be assumed. |
572 | Otherwise, no knowledge of the number of subdirectories will be |
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|
573 | assumed. |
| 510 | |
574 | |
| 511 | Then entries will be sorted into likely directories (everything |
575 | Then entries will be sorted into likely directories a non-initial |
| 512 | without a non-initial dot currently) and likely non-directories |
576 | dot currently) and likely non-directories (see "aio_readdirx"). Then |
| 513 | (everything else). Then every entry plus an appended "/." will be |
577 | every entry plus an appended "/." will be "stat"'ed, likely |
| 514 | "stat"'ed, likely directories first. If that succeeds, it assumes |
578 | directories first, in order of their inode numbers. If that |
| 515 | 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 |
| 516 | be checked seperately). This is often faster than stat'ing the entry |
580 | directory (which will be checked seperately). This is often faster |
| 517 | itself because filesystems might detect the type of the entry |
581 | than stat'ing the entry itself because filesystems might detect the |
| 518 | without reading the inode data (e.g. ext2fs filetype feature). |
582 | type of the entry without reading the inode data (e.g. ext2fs |
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|
583 | filetype feature), even on systems that cannot return the filetype |
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|
584 | information on readdir. |
| 519 | |
585 | |
| 520 | If the known number of directories (link count - 2) has been |
586 | If the known number of directories (link count - 2) has been |
| 521 | 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. |
| 522 | |
588 | |
| 523 | This only works with certainty on POSIX (= UNIX) filesystems, which |
589 | This only works with certainty on POSIX (= UNIX) filesystems, which |
