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Revision 1.62 by root, Sat Aug 25 19:59:18 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
233 IO::AIO::mremap $scalar, $new_length, $flags[, $new_address] 236 IO::AIO::mremap $scalar, $new_length, $flags[, $new_address]
234 IO::AIO::madvise $scalar, $offset, $length, $advice 237 IO::AIO::madvise $scalar, $offset, $length, $advice
235 IO::AIO::mprotect $scalar, $offset, $length, $protect 238 IO::AIO::mprotect $scalar, $offset, $length, $protect
236 IO::AIO::munlock $scalar, $offset = 0, $length = undef 239 IO::AIO::munlock $scalar, $offset = 0, $length = undef
237 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
238 261
239 API NOTES 262 API NOTES
240 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
241 with the same name (sans "aio_"). The arguments are similar or 264 with the same name (sans "aio_"). The arguments are similar or
242 identical, and they all accept an additional (and optional) $callback 265 identical, and they all accept an additional (and optional) $callback
887 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
888 (filesystem) I/O, not for things that wait for other events 911 (filesystem) I/O, not for things that wait for other events
889 (network, other processes), although if you are careful and know 912 (network, other processes), although if you are careful and know
890 what you are doing, you still can. 913 what you are doing, you still can.
891 914
892 The following constants are available (missing ones are, as usual 915 The following constants are available and can be used for normal
893 0): 916 "ioctl" and "fcntl" as well (missing ones are, as usual 0):
894 917
895 "F_DUPFD_CLOEXEC", 918 "F_DUPFD_CLOEXEC",
896 919
897 "F_OFD_GETLK", "F_OFD_SETLK", "F_OFD_GETLKW", 920 "F_OFD_GETLK", "F_OFD_SETLK", "F_OFD_GETLKW",
898 921
899 "FIFREEZE", "FITHAW", "FITRIM", "FICLONE", "FICLONERANGE", 922 "FIFREEZE", "FITHAW", "FITRIM", "FICLONE", "FICLONERANGE",
900 "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".
901 927
902 "FS_IOC_GETFLAGS", "FS_IOC_SETFLAGS", "FS_IOC_GETVERSION", 928 "FS_IOC_GETFLAGS", "FS_IOC_SETFLAGS", "FS_IOC_GETVERSION",
903 "FS_IOC_SETVERSION", "FS_IOC_FIEMAP". 929 "FS_IOC_SETVERSION", "FS_IOC_FIEMAP".
904 930
905 "FS_IOC_FSGETXATTR", "FS_IOC_FSSETXATTR", 931 "FS_IOC_FSGETXATTR", "FS_IOC_FSSETXATTR",
1016 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;
1017 aio_mlock $data; # mlock in background 1043 aio_mlock $data; # mlock in background
1018 1044
1019 aio_mlockall $flags, $callback->($status) 1045 aio_mlockall $flags, $callback->($status)
1020 Calls the "mlockall" function with the given $flags (a combination 1046 Calls the "mlockall" function with the given $flags (a combination
1021 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").
1022 1049
1023 On systems that do not implement "mlockall", this function returns 1050 On systems that do not implement "mlockall", this function returns
1024 -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".
1025 1054
1026 Note that the corresponding "munlockall" is synchronous and is 1055 Note that the corresponding "munlockall" is synchronous and is
1027 documented under "MISCELLANEOUS FUNCTIONS". 1056 documented under "MISCELLANEOUS FUNCTIONS".
1028 1057
1029 Example: asynchronously lock all current and future pages into 1058 Example: asynchronously lock all current and future pages into
1218 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
1219 checking in the "aio_wd" callback, as future requests using the 1248 checking in the "aio_wd" callback, as future requests using the
1220 value will fail in the expected way. 1249 value will fail in the expected way.
1221 1250
1222 IO::AIO::CWD 1251 IO::AIO::CWD
1223 This is a compiletime constant (object) that represents the process 1252 This is a compile time constant (object) that represents the process
1224 current working directory. 1253 current working directory.
1225 1254
1226 Specifying this object as working directory object for a pathname is 1255 Specifying this object as working directory object for a pathname is
1227 as if the pathname would be specified directly, without a directory 1256 as if the pathname would be specified directly, without a directory
1228 object. For example, these calls are functionally identical: 1257 object. For example, these calls are functionally identical:
1638 below, for full accuracy. 1667 below, for full accuracy.
1639 1668
1640 File birth time is only available when the OS and perl support it 1669 File birth time is only available when the OS and perl support it
1641 (on FreeBSD and NetBSD at the time of this writing, although support 1670 (on FreeBSD and NetBSD at the time of this writing, although support
1642 is adaptive, so if your OS/perl gains support, IO::AIO can take 1671 is adaptive, so if your OS/perl gains support, IO::AIO can take
1643 avdantage of it). On systems where it isn't available, 0 is 1672 advantage of it). On systems where it isn't available, 0 is
1644 currently returned, but this might change to "undef" in a future 1673 currently returned, but this might change to "undef" in a future
1645 version. 1674 version.
1646 1675
1647 ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtime 1676 ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtime
1648 Returns access, modification, change and birth time all in one go, 1677 Returns access, modification, change and birth time all in one go,
1664 ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtimensec 1693 ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtimensec
1665 Like the functions above, but returns all four times in one go (and 1694 Like the functions above, but returns all four times in one go (and
1666 maybe more in future versions). 1695 maybe more in future versions).
1667 1696
1668 $counter = IO::AIO::st_gen 1697 $counter = IO::AIO::st_gen
1669 Returns the generation counter of the file. This is only available 1698 Returns the generation counter (in practice this is just a random
1670 on platforms which have this member in their "struct stat" (most 1699 number) of the file. This is only available on platforms which have
1671 BSDs at the time of this writing) and generally only to the root 1700 this member in their "struct stat" (most BSDs at the time of this
1672 usert. If unsupported, 0 is returned, but this might change to 1701 writing) and generally only to the root usert. If unsupported, 0 is
1673 "undef" in a future version. 1702 returned, but this might change to "undef" in a future version.
1674 1703
1675 Example: print the high resolution modification time of /etc, using 1704 Example: print the high resolution modification time of /etc, using
1676 "stat", and "IO::AIO::aio_stat". 1705 "stat", and "IO::AIO::aio_stat".
1677 1706
1678 if (stat "/etc") { 1707 if (stat "/etc") {
1698 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
1699 "Asynchronous I/O" route. Many of these have an asynchronous "aio_*" 1728 "Asynchronous I/O" route. Many of these have an asynchronous "aio_*"
1700 counterpart. 1729 counterpart.
1701 1730
1702 $numfd = IO::AIO::get_fdlimit 1731 $numfd = IO::AIO::get_fdlimit
1703 This function is *EXPERIMENTAL* and subject to change.
1704
1705 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
1706 "undef" and sets $! in case of an error. The limit is one larger 1733 "undef" and sets $! in case of an error. The limit is one larger
1707 than the highest valid file descriptor number. 1734 than the highest valid file descriptor number.
1708 1735
1709 IO::AIO::min_fdlimit [$numfd] 1736 IO::AIO::min_fdlimit [$numfd]
1710 This function is *EXPERIMENTAL* and subject to change.
1711
1712 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
1713 $numfd by changing the soft or hard file descriptor resource limit. 1738 $numfd by changing the soft or hard file descriptor resource limit.
1714 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
1715 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
1716 require. 1741 require.
1803 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
1804 "MAP_ANON" if your system only provides this constant), 1829 "MAP_ANON" if your system only provides this constant),
1805 "IO::AIO::MAP_LOCKED", "IO::AIO::MAP_NORESERVE", 1830 "IO::AIO::MAP_LOCKED", "IO::AIO::MAP_NORESERVE",
1806 "IO::AIO::MAP_POPULATE", "IO::AIO::MAP_NONBLOCK", 1831 "IO::AIO::MAP_POPULATE", "IO::AIO::MAP_NONBLOCK",
1807 "IO::AIO::MAP_FIXED", "IO::AIO::MAP_GROWSDOWN", 1832 "IO::AIO::MAP_FIXED", "IO::AIO::MAP_GROWSDOWN",
1808 "IO::AIO::MAP_32BIT", "IO::AIO::MAP_HUGETLB" or 1833 "IO::AIO::MAP_32BIT", "IO::AIO::MAP_HUGETLB", "IO::AIO::MAP_STACK",
1809 "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".
1810 1836
1811 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.
1812 1838
1813 $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
1814 be a multiple of "IO::AIO::PAGESIZE" and defaults to 0. 1840 be a multiple of "IO::AIO::PAGESIZE" and defaults to 0.
1851 version. 1877 version.
1852 1878
1853 On systems where this call is not supported or is not emulated, this 1879 On systems where this call is not supported or is not emulated, this
1854 call returns falls and sets $! to "ENOSYS". 1880 call returns falls and sets $! to "ENOSYS".
1855 1881
1882 IO::AIO::mlockall $flags
1883 Calls the "eio_mlockall_sync" function, which is like
1884 "aio_mlockall", but is blocking.
1885
1856 IO::AIO::munlock $scalar, $offset = 0, $length = undef 1886 IO::AIO::munlock $scalar, $offset = 0, $length = undef
1857 Calls the "munlock" function, undoing the effects of a previous 1887 Calls the "munlock" function, undoing the effects of a previous
1858 "aio_mlock" call (see its description for details). 1888 "aio_mlock" call (see its description for details).
1859 1889
1860 IO::AIO::munlockall 1890 IO::AIO::munlockall
1861 Calls the "munlockall" function. 1891 Calls the "munlockall" function.
1862 1892
1863 On systems that do not implement "munlockall", this function returns 1893 On systems that do not implement "munlockall", this function returns
1864 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".
1865 1915
1866 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
1867 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
1868 $w_off are "undef", then "NULL" is passed for these, otherwise they 1918 $w_off are "undef", then "NULL" is passed for these, otherwise they
1869 should be the file offset. 1919 should be the file offset.
1910 Example: create a pipe race-free w.r.t. threads and fork: 1960 Example: create a pipe race-free w.r.t. threads and fork:
1911 1961
1912 my ($rfh, $wfh) = IO::AIO::pipe2 IO::AIO::O_CLOEXEC 1962 my ($rfh, $wfh) = IO::AIO::pipe2 IO::AIO::O_CLOEXEC
1913 or die "pipe2: $!\n"; 1963 or die "pipe2: $!\n";
1914 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
1915 $fh = IO::AIO::eventfd [$initval, [$flags]] 2040 $fh = IO::AIO::eventfd [$initval, [$flags]]
1916 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
1917 (unhelpful) defaults for $initval and $flags are 0 for both. 2042 (unhelpful) defaults for $initval and $flags are 0 for both.
1918 2043
1919 On success, the new eventfd filehandle is returned, otherwise 2044 On success, the new eventfd filehandle is returned, otherwise
1926 "IO::AIO::EFD_CLOEXEC", "IO::AIO::EFD_NONBLOCK" and 2051 "IO::AIO::EFD_CLOEXEC", "IO::AIO::EFD_NONBLOCK" and
1927 "IO::AIO::EFD_SEMAPHORE" (Linux 2.6.30). 2052 "IO::AIO::EFD_SEMAPHORE" (Linux 2.6.30).
1928 2053
1929 Example: create a new eventfd filehandle: 2054 Example: create a new eventfd filehandle:
1930 2055
1931 $fh = IO::AIO::eventfd 0, IO::AIO::O_CLOEXEC 2056 $fh = IO::AIO::eventfd 0, IO::AIO::EFD_CLOEXEC
1932 or die "eventfd: $!\n"; 2057 or die "eventfd: $!\n";
1933 2058
1934 $fh = IO::AIO::timerfd_create $clockid[, $flags] 2059 $fh = IO::AIO::timerfd_create $clockid[, $flags]
1935 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
1936 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".
1937 2063
1938 On success, the new timerfd filehandle is returned, otherwise 2064 On success, the new timerfd filehandle is returned, otherwise
1939 returns "undef". If the eventfd syscall is missing, fails with 2065 returns "undef". If the timerfd_create syscall is missing, fails
1940 "ENOSYS". 2066 with "ENOSYS".
1941 2067
1942 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.
1943 2069
1944 The following $clockid values are available: 2070 The following $clockid values are available:
1945 "IO::AIO::CLOCK_REALTIME", "IO::AIO::CLOCK_MONOTONIC" 2071 "IO::AIO::CLOCK_REALTIME", "IO::AIO::CLOCK_MONOTONIC"
2088 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
2089 known issue, rather than a bug. 2215 known issue, rather than a bug.
2090 2216
2091SEE ALSO 2217SEE ALSO
2092 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
2093 more natural syntax. 2219 more natural syntax and IO::FDPass for file descriptor passing.
2094 2220
2095AUTHOR 2221AUTHOR
2096 Marc Lehmann <schmorp@schmorp.de> 2222 Marc Lehmann <schmorp@schmorp.de>
2097 http://home.schmorp.de/ 2223 http://home.schmorp.de/
2098 2224

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