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Revision 1.59 by root, Tue Feb 20 06:54:47 2018 UTC vs.
Revision 1.67 by root, Tue Jul 27 07:58:38 2021 UTC

221 IO::AIO::idle_timeout $seconds 221 IO::AIO::idle_timeout $seconds
222 IO::AIO::max_outstanding $maxreqs 222 IO::AIO::max_outstanding $maxreqs
223 IO::AIO::nreqs 223 IO::AIO::nreqs
224 IO::AIO::nready 224 IO::AIO::nready
225 IO::AIO::npending 225 IO::AIO::npending
226 IO::AIO::reinit
227
226 $nfd = IO::AIO::get_fdlimit [EXPERIMENTAL] 228 $nfd = IO::AIO::get_fdlimit
227 IO::AIO::min_fdlimit $nfd [EXPERIMENTAL] 229 IO::AIO::min_fdlimit $nfd
228 230
229 IO::AIO::sendfile $ofh, $ifh, $offset, $count 231 IO::AIO::sendfile $ofh, $ifh, $offset, $count
230 IO::AIO::fadvise $fh, $offset, $len, $advice 232 IO::AIO::fadvise $fh, $offset, $len, $advice
233
231 IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]] 234 IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]]
232 IO::AIO::munmap $scalar 235 IO::AIO::munmap $scalar
236 IO::AIO::mremap $scalar, $new_length, $flags[, $new_address]
233 IO::AIO::madvise $scalar, $offset, $length, $advice 237 IO::AIO::madvise $scalar, $offset, $length, $advice
234 IO::AIO::mprotect $scalar, $offset, $length, $protect 238 IO::AIO::mprotect $scalar, $offset, $length, $protect
235 IO::AIO::munlock $scalar, $offset = 0, $length = undef 239 IO::AIO::munlock $scalar, $offset = 0, $length = undef
236 IO::AIO::munlockall 240 IO::AIO::munlockall
241
242 # stat extensions
243 $counter = IO::AIO::st_gen
244 $seconds = IO::AIO::st_atime, IO::AIO::st_mtime, IO::AIO::st_ctime, IO::AIO::st_btime
245 ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtime
246 $nanoseconds = IO::AIO::st_atimensec, IO::AIO::st_mtimensec, IO::AIO::st_ctimensec, IO::AIO::st_btimensec
247 $seconds = IO::AIO::st_btimesec
248 ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtimensec
249
250 # very much unportable syscalls
251 IO::AIO::accept4 $r_fh, $sockaddr, $sockaddr_len, $flags
252 IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags
253 IO::AIO::tee $r_fh, $w_fh, $length, $flags
254 $actual_size = IO::AIO::pipesize $r_fh[, $new_size]
255 ($rfh, $wfh) = IO::AIO::pipe2 [$flags]
256 $fh = IO::AIO::memfd_create $pathname[, $flags]
257 $fh = IO::AIO::eventfd [$initval, [$flags]]
258 $fh = IO::AIO::timerfd_create $clockid[, $flags]
259 ($cur_interval, $cur_value) = IO::AIO::timerfd_settime $fh, $flags, $new_interval, $nbw_value
260 ($cur_interval, $cur_value) = IO::AIO::timerfd_gettime $fh
237 261
238 API NOTES 262 API NOTES
239 All the "aio_*" calls are more or less thin wrappers around the syscall 263 All the "aio_*" calls are more or less thin wrappers around the syscall
240 with the same name (sans "aio_"). The arguments are similar or 264 with the same name (sans "aio_"). The arguments are similar or
241 identical, and they all accept an additional (and optional) $callback 265 identical, and they all accept an additional (and optional) $callback
339 "O_APPEND"), the following POSIX and non-POSIX constants are 363 "O_APPEND"), the following POSIX and non-POSIX constants are
340 available (missing ones on your system are, as usual, 0): 364 available (missing ones on your system are, as usual, 0):
341 365
342 "O_ASYNC", "O_DIRECT", "O_NOATIME", "O_CLOEXEC", "O_NOCTTY", 366 "O_ASYNC", "O_DIRECT", "O_NOATIME", "O_CLOEXEC", "O_NOCTTY",
343 "O_NOFOLLOW", "O_NONBLOCK", "O_EXEC", "O_SEARCH", "O_DIRECTORY", 367 "O_NOFOLLOW", "O_NONBLOCK", "O_EXEC", "O_SEARCH", "O_DIRECTORY",
344 "O_DSYNC", "O_RSYNC", "O_SYNC", "O_PATH", "O_TMPFILE", and 368 "O_DSYNC", "O_RSYNC", "O_SYNC", "O_PATH", "O_TMPFILE", "O_TTY_INIT"
345 "O_TTY_INIT". 369 and "O_ACCMODE".
346 370
347 aio_close $fh, $callback->($status) 371 aio_close $fh, $callback->($status)
348 Asynchronously close a file and call the callback with the result 372 Asynchronously close a file and call the callback with the result
349 code. 373 code.
350 374
468 will be emulated by simply reading the data, which would have a 492 will be emulated by simply reading the data, which would have a
469 similar effect. 493 similar effect.
470 494
471 aio_stat $fh_or_path, $callback->($status) 495 aio_stat $fh_or_path, $callback->($status)
472 aio_lstat $fh, $callback->($status) 496 aio_lstat $fh, $callback->($status)
473 Works like perl's "stat" or "lstat" in void context. The callback 497 Works almost exactly like perl's "stat" or "lstat" in void context.
474 will be called after the stat and the results will be available 498 The callback will be called after the stat and the results will be
475 using "stat _" or "-s _" etc... 499 available using "stat _" or "-s _" and other tests (with the
500 exception of "-B" and "-T").
476 501
477 The pathname passed to "aio_stat" must be absolute. See API NOTES, 502 The pathname passed to "aio_stat" must be absolute. See API NOTES,
478 above, for an explanation. 503 above, for an explanation.
479 504
480 Currently, the stats are always 64-bit-stats, i.e. instead of 505 Currently, the stats are always 64-bit-stats, i.e. instead of
488 back on traditional behaviour). 513 back on traditional behaviour).
489 514
490 "S_IFMT", "S_IFIFO", "S_IFCHR", "S_IFBLK", "S_IFLNK", "S_IFREG", 515 "S_IFMT", "S_IFIFO", "S_IFCHR", "S_IFBLK", "S_IFLNK", "S_IFREG",
491 "S_IFDIR", "S_IFWHT", "S_IFSOCK", "IO::AIO::major $dev_t", 516 "S_IFDIR", "S_IFWHT", "S_IFSOCK", "IO::AIO::major $dev_t",
492 "IO::AIO::minor $dev_t", "IO::AIO::makedev $major, $minor". 517 "IO::AIO::minor $dev_t", "IO::AIO::makedev $major, $minor".
518
519 To access higher resolution stat timestamps, see "SUBSECOND STAT
520 TIME ACCESS".
493 521
494 Example: Print the length of /etc/passwd: 522 Example: Print the length of /etc/passwd:
495 523
496 aio_stat "/etc/passwd", sub { 524 aio_stat "/etc/passwd", sub {
497 $_[0] and die "stat failed: $!"; 525 $_[0] and die "stat failed: $!";
544 aio_utime $fh_or_path, $atime, $mtime, $callback->($status) 572 aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
545 Works like perl's "utime" function (including the special case of 573 Works like perl's "utime" function (including the special case of
546 $atime and $mtime being undef). Fractional times are supported if 574 $atime and $mtime being undef). Fractional times are supported if
547 the underlying syscalls support them. 575 the underlying syscalls support them.
548 576
549 When called with a pathname, uses utimes(2) if available, otherwise 577 When called with a pathname, uses utimensat(2) or utimes(2) if
550 utime(2). If called on a file descriptor, uses futimes(2) if 578 available, otherwise utime(2). If called on a file descriptor, uses
551 available, otherwise returns ENOSYS, so this is not portable. 579 futimens(2) or futimes(2) if available, otherwise returns ENOSYS, so
580 this is not portable.
552 581
553 Examples: 582 Examples:
554 583
555 # set atime and mtime to current time (basically touch(1)): 584 # set atime and mtime to current time (basically touch(1)):
556 aio_utime "path", undef, undef; 585 aio_utime "path", undef, undef;
686 The flags are a combination of the following constants, ORed 715 The flags are a combination of the following constants, ORed
687 together (the flags will also be passed to the callback, possibly 716 together (the flags will also be passed to the callback, possibly
688 modified): 717 modified):
689 718
690 IO::AIO::READDIR_DENTS 719 IO::AIO::READDIR_DENTS
691 When this flag is off, then the callback gets an arrayref 720 Normally the callback gets an arrayref consisting of names only
692 consisting of names only (as with "aio_readdir"), otherwise it 721 (as with "aio_readdir"). If this flag is set, then the callback
693 gets an arrayref with "[$name, $type, $inode]" arrayrefs, each 722 gets an arrayref with "[$name, $type, $inode]" arrayrefs, each
694 describing a single directory entry in more detail. 723 describing a single directory entry in more detail:
695 724
696 $name is the name of the entry. 725 $name is the name of the entry.
697 726
698 $type is one of the "IO::AIO::DT_xxx" constants: 727 $type is one of the "IO::AIO::DT_xxx" constants:
699 728
700 "IO::AIO::DT_UNKNOWN", "IO::AIO::DT_FIFO", "IO::AIO::DT_CHR", 729 "IO::AIO::DT_UNKNOWN", "IO::AIO::DT_FIFO", "IO::AIO::DT_CHR",
701 "IO::AIO::DT_DIR", "IO::AIO::DT_BLK", "IO::AIO::DT_REG", 730 "IO::AIO::DT_DIR", "IO::AIO::DT_BLK", "IO::AIO::DT_REG",
702 "IO::AIO::DT_LNK", "IO::AIO::DT_SOCK", "IO::AIO::DT_WHT". 731 "IO::AIO::DT_LNK", "IO::AIO::DT_SOCK", "IO::AIO::DT_WHT".
703 732
704 "IO::AIO::DT_UNKNOWN" means just that: readdir does not know. If 733 "IO::AIO::DT_UNKNOWN" means just that: readdir does not know. If
705 you need to know, you have to run stat yourself. Also, for speed 734 you need to know, you have to run stat yourself. Also, for
706 reasons, the $type scalars are read-only: you can not modify 735 speed/memory reasons, the $type scalars are read-only: you must
707 them. 736 not modify them.
708 737
709 $inode is the inode number (which might not be exact on systems 738 $inode is the inode number (which might not be exact on systems
710 with 64 bit inode numbers and 32 bit perls). This field has 739 with 64 bit inode numbers and 32 bit perls). This field has
711 unspecified content on systems that do not deliver the inode 740 unspecified content on systems that do not deliver the inode
712 information. 741 information.
724 of which names with short names are tried first. 753 of which names with short names are tried first.
725 754
726 IO::AIO::READDIR_STAT_ORDER 755 IO::AIO::READDIR_STAT_ORDER
727 When this flag is set, then the names will be returned in an 756 When this flag is set, then the names will be returned in an
728 order suitable for stat()'ing each one. That is, when you plan 757 order suitable for stat()'ing each one. That is, when you plan
729 to stat() all files in the given directory, then the returned 758 to stat() most or all files in the given directory, then the
730 order will likely be fastest. 759 returned order will likely be faster.
731 760
732 If both this flag and "IO::AIO::READDIR_DIRS_FIRST" are 761 If both this flag and "IO::AIO::READDIR_DIRS_FIRST" are
733 specified, then the likely dirs come first, resulting in a less 762 specified, then the likely dirs come first, resulting in a less
734 optimal stat order. 763 optimal stat order for stat'ing all entries, but likely a more
764 optimal order for finding subdirectories.
735 765
736 IO::AIO::READDIR_FOUND_UNKNOWN 766 IO::AIO::READDIR_FOUND_UNKNOWN
737 This flag should not be set when calling "aio_readdirx". 767 This flag should not be set when calling "aio_readdirx".
738 Instead, it is being set by "aio_readdirx", when any of the 768 Instead, it is being set by "aio_readdirx", when any of the
739 $type's found were "IO::AIO::DT_UNKNOWN". The absence of this 769 $type's found were "IO::AIO::DT_UNKNOWN". The absence of this
880 So in general, you should only use these calls for things that do 910 So in general, you should only use these calls for things that do
881 (filesystem) I/O, not for things that wait for other events 911 (filesystem) I/O, not for things that wait for other events
882 (network, other processes), although if you are careful and know 912 (network, other processes), although if you are careful and know
883 what you are doing, you still can. 913 what you are doing, you still can.
884 914
885 The following constants are available (missing ones are, as usual 915 The following constants are available and can be used for normal
886 0): 916 "ioctl" and "fcntl" as well (missing ones are, as usual 0):
887 917
888 "F_DUPFD_CLOEXEC", 918 "F_DUPFD_CLOEXEC",
889 919
890 "F_OFD_GETLK", "F_OFD_SETLK", "F_OFD_GETLKW", 920 "F_OFD_GETLK", "F_OFD_SETLK", "F_OFD_GETLKW",
891 921
892 "FIFREEZE", "FITHAW", "FITRIM", "FICLONE", "FICLONERANGE", 922 "FIFREEZE", "FITHAW", "FITRIM", "FICLONE", "FICLONERANGE",
893 "FIDEDUPERANGE". 923 "FIDEDUPERANGE".
924
925 "F_ADD_SEALS", "F_GET_SEALS", "F_SEAL_SEAL", "F_SEAL_SHRINK",
926 "F_SEAL_GROW" and "F_SEAL_WRITE".
894 927
895 "FS_IOC_GETFLAGS", "FS_IOC_SETFLAGS", "FS_IOC_GETVERSION", 928 "FS_IOC_GETFLAGS", "FS_IOC_SETFLAGS", "FS_IOC_GETVERSION",
896 "FS_IOC_SETVERSION", "FS_IOC_FIEMAP". 929 "FS_IOC_SETVERSION", "FS_IOC_FIEMAP".
897 930
898 "FS_IOC_FSGETXATTR", "FS_IOC_FSSETXATTR", 931 "FS_IOC_FSGETXATTR", "FS_IOC_FSSETXATTR",
1009 IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh; 1042 IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh;
1010 aio_mlock $data; # mlock in background 1043 aio_mlock $data; # mlock in background
1011 1044
1012 aio_mlockall $flags, $callback->($status) 1045 aio_mlockall $flags, $callback->($status)
1013 Calls the "mlockall" function with the given $flags (a combination 1046 Calls the "mlockall" function with the given $flags (a combination
1014 of "IO::AIO::MCL_CURRENT" and "IO::AIO::MCL_FUTURE"). 1047 of "IO::AIO::MCL_CURRENT", "IO::AIO::MCL_FUTURE" and
1048 "IO::AIO::MCL_ONFAULT").
1015 1049
1016 On systems that do not implement "mlockall", this function returns 1050 On systems that do not implement "mlockall", this function returns
1017 -1 and sets errno to "ENOSYS". 1051 -1 and sets errno to "ENOSYS". Similarly, flag combinations not
1052 supported by the system result in a return value of -1 with errno
1053 being set to "EINVAL".
1018 1054
1019 Note that the corresponding "munlockall" is synchronous and is 1055 Note that the corresponding "munlockall" is synchronous and is
1020 documented under "MISCELLANEOUS FUNCTIONS". 1056 documented under "MISCELLANEOUS FUNCTIONS".
1021 1057
1022 Example: asynchronously lock all current and future pages into 1058 Example: asynchronously lock all current and future pages into
1211 fails the request with "ENOENT", there is often no need for error 1247 fails the request with "ENOENT", there is often no need for error
1212 checking in the "aio_wd" callback, as future requests using the 1248 checking in the "aio_wd" callback, as future requests using the
1213 value will fail in the expected way. 1249 value will fail in the expected way.
1214 1250
1215 IO::AIO::CWD 1251 IO::AIO::CWD
1216 This is a compiletime constant (object) that represents the process 1252 This is a compile time constant (object) that represents the process
1217 current working directory. 1253 current working directory.
1218 1254
1219 Specifying this object as working directory object for a pathname is 1255 Specifying this object as working directory object for a pathname is
1220 as if the pathname would be specified directly, without a directory 1256 as if the pathname would be specified directly, without a directory
1221 object. For example, these calls are functionally identical: 1257 object. For example, these calls are functionally identical:
1446 Strictly equivalent to: 1482 Strictly equivalent to:
1447 1483
1448 IO::AIO::poll_wait, IO::AIO::poll_cb 1484 IO::AIO::poll_wait, IO::AIO::poll_cb
1449 while IO::AIO::nreqs; 1485 while IO::AIO::nreqs;
1450 1486
1487 This function can be useful at program aborts, to make sure
1488 outstanding I/O has been done ("IO::AIO" uses an "END" block which
1489 already calls this function on normal exits), or when you are merely
1490 using "IO::AIO" for its more advanced functions, rather than for
1491 async I/O, e.g.:
1492
1493 my ($dirs, $nondirs);
1494 IO::AIO::aio_scandir "/tmp", 0, sub { ($dirs, $nondirs) = @_ };
1495 IO::AIO::flush;
1496 # $dirs, $nondirs are now set
1497
1451 IO::AIO::max_poll_reqs $nreqs 1498 IO::AIO::max_poll_reqs $nreqs
1452 IO::AIO::max_poll_time $seconds 1499 IO::AIO::max_poll_time $seconds
1453 These set the maximum number of requests (default 0, meaning 1500 These set the maximum number of requests (default 0, meaning
1454 infinity) that are being processed by "IO::AIO::poll_cb" in one 1501 infinity) that are being processed by "IO::AIO::poll_cb" in one
1455 call, respectively the maximum amount of time (default 0, meaning 1502 call, respectively the maximum amount of time (default 0, meaning
1588 1635
1589 IO::AIO::npending 1636 IO::AIO::npending
1590 Returns the number of requests currently in the pending state 1637 Returns the number of requests currently in the pending state
1591 (executed, but not yet processed by poll_cb). 1638 (executed, but not yet processed by poll_cb).
1592 1639
1640 SUBSECOND STAT TIME ACCESS
1641 Both "aio_stat"/"aio_lstat" and perl's "stat"/"lstat" functions can
1642 generally find access/modification and change times with subsecond time
1643 accuracy of the system supports it, but perl's built-in functions only
1644 return the integer part.
1645
1646 The following functions return the timestamps of the most recent stat
1647 with subsecond precision on most systems and work both after
1648 "aio_stat"/"aio_lstat" and perl's "stat"/"lstat" calls. Their return
1649 value is only meaningful after a successful "stat"/"lstat" call, or
1650 during/after a successful "aio_stat"/"aio_lstat" callback.
1651
1652 This is similar to the Time::HiRes "stat" functions, but can return full
1653 resolution without rounding and work with standard perl "stat",
1654 alleviating the need to call the special "Time::HiRes" functions, which
1655 do not act like their perl counterparts.
1656
1657 On operating systems or file systems where subsecond time resolution is
1658 not supported or could not be detected, a fractional part of 0 is
1659 returned, so it is always safe to call these functions.
1660
1661 $seconds = IO::AIO::st_atime, IO::AIO::st_mtime, IO::AIO::st_ctime,
1662 IO::AIO::st_btime
1663 Return the access, modication, change or birth time, respectively,
1664 including fractional part. Due to the limited precision of floating
1665 point, the accuracy on most platforms is only a bit better than
1666 milliseconds for times around now - see the *nsec* function family,
1667 below, for full accuracy.
1668
1669 File birth time is only available when the OS and perl support it
1670 (on FreeBSD and NetBSD at the time of this writing, although support
1671 is adaptive, so if your OS/perl gains support, IO::AIO can take
1672 advantage of it). On systems where it isn't available, 0 is
1673 currently returned, but this might change to "undef" in a future
1674 version.
1675
1676 ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtime
1677 Returns access, modification, change and birth time all in one go,
1678 and maybe more times in the future version.
1679
1680 $nanoseconds = IO::AIO::st_atimensec, IO::AIO::st_mtimensec,
1681 IO::AIO::st_ctimensec, IO::AIO::st_btimensec
1682 Return the fractional access, modifcation, change or birth time, in
1683 nanoseconds, as an integer in the range 0 to 999999999.
1684
1685 Note that no accessors are provided for access, modification and
1686 change times - you need to get those from "stat _" if required ("int
1687 IO::AIO::st_atime" and so on will *not* generally give you the
1688 correct value).
1689
1690 $seconds = IO::AIO::st_btimesec
1691 The (integral) seconds part of the file birth time, if available.
1692
1693 ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtimensec
1694 Like the functions above, but returns all four times in one go (and
1695 maybe more in future versions).
1696
1697 $counter = IO::AIO::st_gen
1698 Returns the generation counter (in practice this is just a random
1699 number) of the file. This is only available on platforms which have
1700 this member in their "struct stat" (most BSDs at the time of this
1701 writing) and generally only to the root usert. If unsupported, 0 is
1702 returned, but this might change to "undef" in a future version.
1703
1704 Example: print the high resolution modification time of /etc, using
1705 "stat", and "IO::AIO::aio_stat".
1706
1707 if (stat "/etc") {
1708 printf "stat(/etc) mtime: %f\n", IO::AIO::st_mtime;
1709 }
1710
1711 IO::AIO::aio_stat "/etc", sub {
1712 $_[0]
1713 and return;
1714
1715 printf "aio_stat(/etc) mtime: %d.%09d\n", (stat _)[9], IO::AIO::st_mtimensec;
1716 };
1717
1718 IO::AIO::flush;
1719
1720 Output of the awbove on my system, showing reduced and full accuracy:
1721
1722 stat(/etc) mtime: 1534043702.020808
1723 aio_stat(/etc) mtime: 1534043702.020807792
1724
1593 MISCELLANEOUS FUNCTIONS 1725 MISCELLANEOUS FUNCTIONS
1594 IO::AIO implements some functions that are useful when you want to use 1726 IO::AIO implements some functions that are useful when you want to use
1595 some "Advanced I/O" function not available to in Perl, without going the 1727 some "Advanced I/O" function not available to in Perl, without going the
1596 "Asynchronous I/O" route. Many of these have an asynchronous "aio_*" 1728 "Asynchronous I/O" route. Many of these have an asynchronous "aio_*"
1597 counterpart. 1729 counterpart.
1598 1730
1599 $numfd = IO::AIO::get_fdlimit 1731 $numfd = IO::AIO::get_fdlimit
1600 This function is *EXPERIMENTAL* and subject to change.
1601
1602 Tries to find the current file descriptor limit and returns it, or 1732 Tries to find the current file descriptor limit and returns it, or
1603 "undef" and sets $! in case of an error. The limit is one larger 1733 "undef" and sets $! in case of an error. The limit is one larger
1604 than the highest valid file descriptor number. 1734 than the highest valid file descriptor number.
1605 1735
1606 IO::AIO::min_fdlimit [$numfd] 1736 IO::AIO::min_fdlimit [$numfd]
1607 This function is *EXPERIMENTAL* and subject to change.
1608
1609 Try to increase the current file descriptor limit(s) to at least 1737 Try to increase the current file descriptor limit(s) to at least
1610 $numfd by changing the soft or hard file descriptor resource limit. 1738 $numfd by changing the soft or hard file descriptor resource limit.
1611 If $numfd is missing, it will try to set a very high limit, although 1739 If $numfd is missing, it will try to set a very high limit, although
1612 this is not recommended when you know the actual minimum that you 1740 this is not recommended when you know the actual minimum that you
1613 require. 1741 require.
1700 not available, the are 0): "IO::AIO::MAP_ANONYMOUS" (which is set to 1828 not available, the are 0): "IO::AIO::MAP_ANONYMOUS" (which is set to
1701 "MAP_ANON" if your system only provides this constant), 1829 "MAP_ANON" if your system only provides this constant),
1702 "IO::AIO::MAP_LOCKED", "IO::AIO::MAP_NORESERVE", 1830 "IO::AIO::MAP_LOCKED", "IO::AIO::MAP_NORESERVE",
1703 "IO::AIO::MAP_POPULATE", "IO::AIO::MAP_NONBLOCK", 1831 "IO::AIO::MAP_POPULATE", "IO::AIO::MAP_NONBLOCK",
1704 "IO::AIO::MAP_FIXED", "IO::AIO::MAP_GROWSDOWN", 1832 "IO::AIO::MAP_FIXED", "IO::AIO::MAP_GROWSDOWN",
1705 "IO::AIO::MAP_32BIT", "IO::AIO::MAP_HUGETLB" or 1833 "IO::AIO::MAP_32BIT", "IO::AIO::MAP_HUGETLB", "IO::AIO::MAP_STACK",
1706 "IO::AIO::MAP_STACK". 1834 "IO::AIO::MAP_FIXED_NOREPLACE", "IO::AIO::MAP_SHARED_VALIDATE",
1835 "IO::AIO::MAP_SYNC" or "IO::AIO::MAP_UNINITIALIZED".
1707 1836
1708 If $fh is "undef", then a file descriptor of -1 is passed. 1837 If $fh is "undef", then a file descriptor of -1 is passed.
1709 1838
1710 $offset is the offset from the start of the file - it generally must 1839 $offset is the offset from the start of the file - it generally must
1711 be a multiple of "IO::AIO::PAGESIZE" and defaults to 0. 1840 be a multiple of "IO::AIO::PAGESIZE" and defaults to 0.
1723 1852
1724 my $fast_md5 = md5 $data; 1853 my $fast_md5 = md5 $data;
1725 1854
1726 IO::AIO::munmap $scalar 1855 IO::AIO::munmap $scalar
1727 Removes a previous mmap and undefines the $scalar. 1856 Removes a previous mmap and undefines the $scalar.
1857
1858 IO::AIO::mremap $scalar, $new_length, $flags = MREMAP_MAYMOVE[,
1859 $new_address = 0]
1860 Calls the Linux-specific mremap(2) system call. The $scalar must
1861 have been mapped by "IO::AIO::mmap", and $flags must currently
1862 either be 0 or "IO::AIO::MREMAP_MAYMOVE".
1863
1864 Returns true if successful, and false otherwise. If the underlying
1865 mmapped region has changed address, then the true value has the
1866 numerical value 1, otherwise it has the numerical value 0:
1867
1868 my $success = IO::AIO::mremap $mmapped, 8192, IO::AIO::MREMAP_MAYMOVE
1869 or die "mremap: $!";
1870
1871 if ($success*1) {
1872 warn "scalar has chanegd address in memory\n";
1873 }
1874
1875 "IO::AIO::MREMAP_FIXED" and the $new_address argument are currently
1876 implemented, but not supported and might go away in a future
1877 version.
1878
1879 On systems where this call is not supported or is not emulated, this
1880 call returns falls and sets $! to "ENOSYS".
1881
1882 IO::AIO::mlockall $flags
1883 Calls the "eio_mlockall_sync" function, which is like
1884 "aio_mlockall", but is blocking.
1728 1885
1729 IO::AIO::munlock $scalar, $offset = 0, $length = undef 1886 IO::AIO::munlock $scalar, $offset = 0, $length = undef
1730 Calls the "munlock" function, undoing the effects of a previous 1887 Calls the "munlock" function, undoing the effects of a previous
1731 "aio_mlock" call (see its description for details). 1888 "aio_mlock" call (see its description for details).
1732 1889
1733 IO::AIO::munlockall 1890 IO::AIO::munlockall
1734 Calls the "munlockall" function. 1891 Calls the "munlockall" function.
1735 1892
1736 On systems that do not implement "munlockall", this function returns 1893 On systems that do not implement "munlockall", this function returns
1737 ENOSYS, otherwise the return value of "munlockall". 1894 ENOSYS, otherwise the return value of "munlockall".
1895
1896 $fh = IO::AIO::accept4 $r_fh, $sockaddr, $sockaddr_maxlen, $flags
1897 Uses the GNU/Linux accept4(2) syscall, if available, to accept a
1898 socket and return the new file handle on success, or sets $! and
1899 returns "undef" on error.
1900
1901 The remote name of the new socket will be stored in $sockaddr, which
1902 will be extended to allow for at least $sockaddr_maxlen octets. If
1903 the socket name does not fit into $sockaddr_maxlen octets, this is
1904 signaled by returning a longer string in $sockaddr, which might or
1905 might not be truncated.
1906
1907 To accept name-less sockets, use "undef" for $sockaddr and 0 for
1908 $sockaddr_maxlen.
1909
1910 The main reasons to use this syscall rather than portable accept(2)
1911 are that you can specify "SOCK_NONBLOCK" and/or "SOCK_CLOEXEC" flags
1912 and you can accept name-less sockets by specifying 0 for
1913 $sockaddr_maxlen, which is sadly not possible with perl's interface
1914 to "accept".
1738 1915
1739 IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags 1916 IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags
1740 Calls the GNU/Linux splice(2) syscall, if available. If $r_off or 1917 Calls the GNU/Linux splice(2) syscall, if available. If $r_off or
1741 $w_off are "undef", then "NULL" is passed for these, otherwise they 1918 $w_off are "undef", then "NULL" is passed for these, otherwise they
1742 should be the file offset. 1919 should be the file offset.
1783 Example: create a pipe race-free w.r.t. threads and fork: 1960 Example: create a pipe race-free w.r.t. threads and fork:
1784 1961
1785 my ($rfh, $wfh) = IO::AIO::pipe2 IO::AIO::O_CLOEXEC 1962 my ($rfh, $wfh) = IO::AIO::pipe2 IO::AIO::O_CLOEXEC
1786 or die "pipe2: $!\n"; 1963 or die "pipe2: $!\n";
1787 1964
1965 $fh = IO::AIO::memfd_create $pathname[, $flags]
1966 This is a direct interface to the Linux memfd_create(2) system call.
1967 The (unhelpful) default for $flags is 0, but your default should be
1968 "IO::AIO::MFD_CLOEXEC".
1969
1970 On success, the new memfd filehandle is returned, otherwise returns
1971 "undef". If the memfd_create syscall is missing, fails with
1972 "ENOSYS".
1973
1974 Please refer to memfd_create(2) for more info on this call.
1975
1976 The following $flags values are available: "IO::AIO::MFD_CLOEXEC",
1977 "IO::AIO::MFD_ALLOW_SEALING" and "IO::AIO::MFD_HUGETLB".
1978
1979 Example: create a new memfd.
1980
1981 my $fh = IO::AIO::memfd_create "somenameforprocfd", IO::AIO::MFD_CLOEXEC
1982 or die "memfd_create: $!\n";
1983
1984 $fh = IO::AIO::pidfd_open $pid[, $flags]
1985 This is an interface to the Linux pidfd_open(2) system call. The
1986 default for $flags is 0.
1987
1988 On success, a new pidfd filehandle is returned (that is already set
1989 to close-on-exec), otherwise returns "undef". If the syscall is
1990 missing, fails with "ENOSYS".
1991
1992 Example: open pid 6341 as pidfd.
1993
1994 my $fh = IO::AIO::pidfd_open 6341
1995 or die "pidfd_open: $!\n";
1996
1997 $status = IO::AIO::pidfd_send_signal $pidfh, $signal[, $siginfo[,
1998 $flags]]
1999 This is an interface to the Linux pidfd_send_signal system call. The
2000 default for $siginfo is "undef" and the default for $flags is 0.
2001
2002 Returns the system call status. If the syscall is missing, fails
2003 with "ENOSYS".
2004
2005 When specified, $siginfo must be a reference to a hash with one or
2006 more of the following members:
2007
2008 code - the "si_code" member
2009 pid - the "si_pid" member
2010 uid - the "si_uid" member
2011 value_int - the "si_value.sival_int" member
2012 value_ptr - the "si_value.sival_ptr" member, specified as an integer
2013
2014 Example: send a SIGKILL to the specified process.
2015
2016 my $status = IO::AIO::pidfd_send_signal $pidfh, 9, undef
2017 and die "pidfd_send_signal: $!\n";
2018
2019 Example: send a SIGKILL to the specified process with extra data.
2020
2021 my $status = IO::AIO::pidfd_send_signal $pidfh, 9, { code => -1, value_int => 7 }
2022 and die "pidfd_send_signal: $!\n";
2023
2024 $fh = IO::AIO::pidfd_getfd $pidfh, $targetfd[, $flags]
2025 This is an interface to the Linux pidfd_getfd system call. The
2026 default for $flags is 0.
2027
2028 On success, returns a dup'ed copy of the target file descriptor
2029 (specified as an integer) returned (that is already set to
2030 close-on-exec), otherwise returns "undef". If the syscall is
2031 missing, fails with "ENOSYS".
2032
2033 Example: get a copy of standard error of another process and print
2034 soemthing to it.
2035
2036 my $errfh = IO::AIO::pidfd_getfd $pidfh, 2
2037 or die "pidfd_getfd: $!\n";
2038 print $errfh "stderr\n";
2039
1788 $fh = IO::AIO::eventfd [$initval, [$flags]] 2040 $fh = IO::AIO::eventfd [$initval, [$flags]]
1789 This is a direct interface to the Linux eventfd(2) system call. The 2041 This is a direct interface to the Linux eventfd(2) system call. The
1790 (unhelpful) defaults for $initval and $flags are 0 for both. 2042 (unhelpful) defaults for $initval and $flags are 0 for both.
1791 2043
1792 On success, the new eventfd filehandle is returned, otherwise 2044 On success, the new eventfd filehandle is returned, otherwise
1799 "IO::AIO::EFD_CLOEXEC", "IO::AIO::EFD_NONBLOCK" and 2051 "IO::AIO::EFD_CLOEXEC", "IO::AIO::EFD_NONBLOCK" and
1800 "IO::AIO::EFD_SEMAPHORE" (Linux 2.6.30). 2052 "IO::AIO::EFD_SEMAPHORE" (Linux 2.6.30).
1801 2053
1802 Example: create a new eventfd filehandle: 2054 Example: create a new eventfd filehandle:
1803 2055
1804 $fh = IO::AIO::eventfd 0, IO::AIO::O_CLOEXEC 2056 $fh = IO::AIO::eventfd 0, IO::AIO::EFD_CLOEXEC
1805 or die "eventfd: $!\n"; 2057 or die "eventfd: $!\n";
1806 2058
1807 $fh = IO::AIO::timerfd_create $clockid[, $flags] 2059 $fh = IO::AIO::timerfd_create $clockid[, $flags]
1808 This is a direct interface to the Linux timerfd_create(2) system 2060 This is a direct interface to the Linux timerfd_create(2) system
1809 call. The (unhelpful) default for $flags is 0. 2061 call. The (unhelpful) default for $flags is 0, but your default
2062 should be "IO::AIO::TFD_CLOEXEC".
1810 2063
1811 On success, the new timerfd filehandle is returned, otherwise 2064 On success, the new timerfd filehandle is returned, otherwise
1812 returns "undef". If the eventfd syscall is missing, fails with 2065 returns "undef". If the timerfd_create syscall is missing, fails
1813 "ENOSYS". 2066 with "ENOSYS".
1814 2067
1815 Please refer to timerfd_create(2) for more info on this call. 2068 Please refer to timerfd_create(2) for more info on this call.
1816 2069
1817 The following $clockid values are available: 2070 The following $clockid values are available:
1818 "IO::AIO::CLOCK_REALTIME", "IO::AIO::CLOCK_MONOTONIC" 2071 "IO::AIO::CLOCK_REALTIME", "IO::AIO::CLOCK_MONOTONIC"
1961 I am not sure anything can be done about this, so this is considered a 2214 I am not sure anything can be done about this, so this is considered a
1962 known issue, rather than a bug. 2215 known issue, rather than a bug.
1963 2216
1964SEE ALSO 2217SEE ALSO
1965 AnyEvent::AIO for easy integration into event loops, Coro::AIO for a 2218 AnyEvent::AIO for easy integration into event loops, Coro::AIO for a
1966 more natural syntax. 2219 more natural syntax and IO::FDPass for file descriptor passing.
1967 2220
1968AUTHOR 2221AUTHOR
1969 Marc Lehmann <schmorp@schmorp.de> 2222 Marc Lehmann <schmorp@schmorp.de>
1970 http://home.schmorp.de/ 2223 http://home.schmorp.de/
1971 2224

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