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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.267 by root, Tue Aug 9 11:39:17 2016 UTC vs.
Revision 1.302 by root, Wed Apr 3 03:03:53 2019 UTC

… …
171use common::sense; 171use common::sense;
172 172
173use base 'Exporter'; 173use base 'Exporter';
174 174
175BEGIN { 175BEGIN {
176 our $VERSION = 4.34; 176 our $VERSION = 4.72;
177 177
178 our @AIO_REQ = qw(aio_sendfile aio_seek aio_read aio_write aio_open aio_close 178 our @AIO_REQ = qw(aio_sendfile aio_seek aio_read aio_write aio_open aio_close
179 aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx 179 aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx
180 aio_scandir aio_symlink aio_readlink aio_realpath aio_fcntl aio_ioctl 180 aio_scandir aio_symlink aio_readlink aio_realpath aio_fcntl aio_ioctl
181 aio_sync aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range 181 aio_sync aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range
182 aio_pathsync aio_readahead aio_fiemap aio_allocate 182 aio_pathsync aio_readahead aio_fiemap aio_allocate
183 aio_rename aio_link aio_move aio_copy aio_group 183 aio_rename aio_rename2 aio_link aio_move aio_copy aio_group
184 aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown 184 aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown
185 aio_chmod aio_utime aio_truncate 185 aio_chmod aio_utime aio_truncate
186 aio_msync aio_mtouch aio_mlock aio_mlockall 186 aio_msync aio_mtouch aio_mlock aio_mlockall
187 aio_statvfs 187 aio_statvfs
188 aio_slurp
188 aio_wd); 189 aio_wd);
189 190
190 our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice)); 191 our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice));
191 our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush 192 our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush
192 min_parallel max_parallel max_idle idle_timeout 193 min_parallel max_parallel max_idle idle_timeout
193 nreqs nready npending nthreads 194 nreqs nready npending nthreads
194 max_poll_time max_poll_reqs 195 max_poll_time max_poll_reqs
195 sendfile fadvise madvise 196 sendfile fadvise madvise
196 mmap munmap munlock munlockall); 197 mmap munmap mremap munlock munlockall);
197 198
198 push @AIO_REQ, qw(aio_busy); # not exported 199 push @AIO_REQ, qw(aio_busy); # not exported
199 200
200 @IO::AIO::GRP::ISA = 'IO::AIO::REQ'; 201 @IO::AIO::GRP::ISA = 'IO::AIO::REQ';
201 202
… …
233 aio_link $srcpath, $dstpath, $callback->($status) 234 aio_link $srcpath, $dstpath, $callback->($status)
234 aio_symlink $srcpath, $dstpath, $callback->($status) 235 aio_symlink $srcpath, $dstpath, $callback->($status)
235 aio_readlink $pathname, $callback->($link) 236 aio_readlink $pathname, $callback->($link)
236 aio_realpath $pathname, $callback->($path) 237 aio_realpath $pathname, $callback->($path)
237 aio_rename $srcpath, $dstpath, $callback->($status) 238 aio_rename $srcpath, $dstpath, $callback->($status)
239 aio_rename2 $srcpath, $dstpath, $flags, $callback->($status)
238 aio_mkdir $pathname, $mode, $callback->($status) 240 aio_mkdir $pathname, $mode, $callback->($status)
239 aio_rmdir $pathname, $callback->($status) 241 aio_rmdir $pathname, $callback->($status)
240 aio_readdir $pathname, $callback->($entries) 242 aio_readdir $pathname, $callback->($entries)
241 aio_readdirx $pathname, $flags, $callback->($entries, $flags) 243 aio_readdirx $pathname, $flags, $callback->($entries, $flags)
242 IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST 244 IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST
… …
252 aio_syncfs $fh, $callback->($status) 254 aio_syncfs $fh, $callback->($status)
253 aio_fsync $fh, $callback->($status) 255 aio_fsync $fh, $callback->($status)
254 aio_fdatasync $fh, $callback->($status) 256 aio_fdatasync $fh, $callback->($status)
255 aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) 257 aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
256 aio_pathsync $pathname, $callback->($status) 258 aio_pathsync $pathname, $callback->($status)
257 aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) 259 aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status)
258 aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) 260 aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
259 aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) 261 aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
260 aio_mlockall $flags, $callback->($status) 262 aio_mlockall $flags, $callback->($status)
261 aio_group $callback->(...) 263 aio_group $callback->(...)
262 aio_nop $callback->() 264 aio_nop $callback->()
… …
276 IO::AIO::idle_timeout $seconds 278 IO::AIO::idle_timeout $seconds
277 IO::AIO::max_outstanding $maxreqs 279 IO::AIO::max_outstanding $maxreqs
278 IO::AIO::nreqs 280 IO::AIO::nreqs
279 IO::AIO::nready 281 IO::AIO::nready
280 IO::AIO::npending 282 IO::AIO::npending
283 IO::AIO::reinit
284
285 $nfd = IO::AIO::get_fdlimit [EXPERIMENTAL]
286 IO::AIO::min_fdlimit $nfd [EXPERIMENTAL]
281 287
282 IO::AIO::sendfile $ofh, $ifh, $offset, $count 288 IO::AIO::sendfile $ofh, $ifh, $offset, $count
283 IO::AIO::fadvise $fh, $offset, $len, $advice 289 IO::AIO::fadvise $fh, $offset, $len, $advice
290
284 IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]] 291 IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]]
285 IO::AIO::munmap $scalar 292 IO::AIO::munmap $scalar
293 IO::AIO::mremap $scalar, $new_length, $flags[, $new_address]
286 IO::AIO::madvise $scalar, $offset, $length, $advice 294 IO::AIO::madvise $scalar, $offset, $length, $advice
287 IO::AIO::mprotect $scalar, $offset, $length, $protect 295 IO::AIO::mprotect $scalar, $offset, $length, $protect
288 IO::AIO::munlock $scalar, $offset = 0, $length = undef 296 IO::AIO::munlock $scalar, $offset = 0, $length = undef
289 IO::AIO::munlockall 297 IO::AIO::munlockall
298
299 # stat extensions
300 $counter = IO::AIO::st_gen
301 $seconds = IO::AIO::st_atime, IO::AIO::st_mtime, IO::AIO::st_ctime, IO::AIO::st_btime
302 ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtime
303 $nanoseconds = IO::AIO::st_atimensec, IO::AIO::st_mtimensec, IO::AIO::st_ctimensec, IO::AIO::st_btimensec
304 $seconds = IO::AIO::st_btimesec
305 ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtimensec
306
307 # very much unportable syscalls
308 IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags
309 IO::AIO::tee $r_fh, $w_fh, $length, $flags
310 $actual_size = IO::AIO::pipesize $r_fh[, $new_size]
311 ($rfh, $wfh) = IO::AIO::pipe2 [$flags]
312 $fh = IO::AIO::memfd_create $pathname[, $flags]
313 $fh = IO::AIO::eventfd [$initval, [$flags]]
314 $fh = IO::AIO::timerfd_create $clockid[, $flags]
315 ($cur_interval, $cur_value) = IO::AIO::timerfd_settime $fh, $flags, $new_interval, $nbw_value
316 ($cur_interval, $cur_value) = IO::AIO::timerfd_gettime $fh
290 317
291=head2 API NOTES 318=head2 API NOTES
292 319
293All the C<aio_*> calls are more or less thin wrappers around the syscall 320All the C<aio_*> calls are more or less thin wrappers around the syscall
294with the same name (sans C<aio_>). The arguments are similar or identical, 321with the same name (sans C<aio_>). The arguments are similar or identical,
… …
400following POSIX and non-POSIX constants are available (missing ones on 427following POSIX and non-POSIX constants are available (missing ones on
401your system are, as usual, C<0>): 428your system are, as usual, C<0>):
402 429
403C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>, 430C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>,
404C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>, 431C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>,
405C<O_RSYNC>, C<O_SYNC>, C<O_PATH>, C<O_TMPFILE>, and C<O_TTY_INIT>. 432C<O_RSYNC>, C<O_SYNC>, C<O_PATH>, C<O_TMPFILE>, C<O_TTY_INIT> and C<O_ACCMODE>.
406 433
407 434
408=item aio_close $fh, $callback->($status) 435=item aio_close $fh, $callback->($status)
409 436
410Asynchronously close a file and call the callback with the result 437Asynchronously close a file and call the callback with the result
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536 563
537=item aio_stat $fh_or_path, $callback->($status) 564=item aio_stat $fh_or_path, $callback->($status)
538 565
539=item aio_lstat $fh, $callback->($status) 566=item aio_lstat $fh, $callback->($status)
540 567
541Works like perl's C<stat> or C<lstat> in void context. The callback will 568Works almost exactly like perl's C<stat> or C<lstat> in void context. The
542be called after the stat and the results will be available using C<stat _> 569callback will be called after the stat and the results will be available
543or C<-s _> etc... 570using C<stat _> or C<-s _> and other tests (with the exception of C<-B>
571and C<-T>).
544 572
545The pathname passed to C<aio_stat> must be absolute. See API NOTES, above, 573The pathname passed to C<aio_stat> must be absolute. See API NOTES, above,
546for an explanation. 574for an explanation.
547 575
548Currently, the stats are always 64-bit-stats, i.e. instead of returning an 576Currently, the stats are always 64-bit-stats, i.e. instead of returning an
… …
555behaviour). 583behaviour).
556 584
557C<S_IFMT>, C<S_IFIFO>, C<S_IFCHR>, C<S_IFBLK>, C<S_IFLNK>, C<S_IFREG>, 585C<S_IFMT>, C<S_IFIFO>, C<S_IFCHR>, C<S_IFBLK>, C<S_IFLNK>, C<S_IFREG>,
558C<S_IFDIR>, C<S_IFWHT>, C<S_IFSOCK>, C<IO::AIO::major $dev_t>, 586C<S_IFDIR>, C<S_IFWHT>, C<S_IFSOCK>, C<IO::AIO::major $dev_t>,
559C<IO::AIO::minor $dev_t>, C<IO::AIO::makedev $major, $minor>. 587C<IO::AIO::minor $dev_t>, C<IO::AIO::makedev $major, $minor>.
588
589To access higher resolution stat timestamps, see L<SUBSECOND STAT TIME
590ACCESS>.
560 591
561Example: Print the length of F</etc/passwd>: 592Example: Print the length of F</etc/passwd>:
562 593
563 aio_stat "/etc/passwd", sub { 594 aio_stat "/etc/passwd", sub {
564 $_[0] and die "stat failed: $!"; 595 $_[0] and die "stat failed: $!";
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608 namemax => 255, 639 namemax => 255,
609 frsize => 1024, 640 frsize => 1024,
610 fsid => 1810 641 fsid => 1810
611 } 642 }
612 643
613Here is a (likely partial - send me updates!) list of fsid values used by
614Linux - it is safe to hardcode these when C<$^O> is C<linux>:
615
616 0x0000adf5 adfs
617 0x0000adff affs
618 0x5346414f afs
619 0x09041934 anon-inode filesystem
620 0x00000187 autofs
621 0x42465331 befs
622 0x1badface bfs
623 0x42494e4d binfmt_misc
624 0x9123683e btrfs
625 0x0027e0eb cgroupfs
626 0xff534d42 cifs
627 0x73757245 coda
628 0x012ff7b7 coh
629 0x28cd3d45 cramfs
630 0x453dcd28 cramfs-wend (wrong endianness)
631 0x64626720 debugfs
632 0x00001373 devfs
633 0x00001cd1 devpts
634 0x0000f15f ecryptfs
635 0x00414a53 efs
636 0x0000137d ext
637 0x0000ef53 ext2/ext3/ext4
638 0x0000ef51 ext2
639 0xf2f52010 f2fs
640 0x00004006 fat
641 0x65735546 fuseblk
642 0x65735543 fusectl
643 0x0bad1dea futexfs
644 0x01161970 gfs2
645 0x47504653 gpfs
646 0x00004244 hfs
647 0xf995e849 hpfs
648 0x00c0ffee hostfs
649 0x958458f6 hugetlbfs
650 0x2bad1dea inotifyfs
651 0x00009660 isofs
652 0x000072b6 jffs2
653 0x3153464a jfs
654 0x6b414653 k-afs
655 0x0bd00bd0 lustre
656 0x0000137f minix
657 0x0000138f minix 30 char names
658 0x00002468 minix v2
659 0x00002478 minix v2 30 char names
660 0x00004d5a minix v3
661 0x19800202 mqueue
662 0x00004d44 msdos
663 0x0000564c novell
664 0x00006969 nfs
665 0x6e667364 nfsd
666 0x00003434 nilfs
667 0x5346544e ntfs
668 0x00009fa1 openprom
669 0x7461636F ocfs2
670 0x00009fa0 proc
671 0x6165676c pstorefs
672 0x0000002f qnx4
673 0x68191122 qnx6
674 0x858458f6 ramfs
675 0x52654973 reiserfs
676 0x00007275 romfs
677 0x67596969 rpc_pipefs
678 0x73636673 securityfs
679 0xf97cff8c selinux
680 0x0000517b smb
681 0x534f434b sockfs
682 0x73717368 squashfs
683 0x62656572 sysfs
684 0x012ff7b6 sysv2
685 0x012ff7b5 sysv4
686 0x01021994 tmpfs
687 0x15013346 udf
688 0x00011954 ufs
689 0x54190100 ufs byteswapped
690 0x00009fa2 usbdevfs
691 0x01021997 v9fs
692 0xa501fcf5 vxfs
693 0xabba1974 xenfs
694 0x012ff7b4 xenix
695 0x58465342 xfs
696 0x012fd16d xia
697
698=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status) 644=item aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
699 645
700Works like perl's C<utime> function (including the special case of $atime 646Works like perl's C<utime> function (including the special case of $atime
701and $mtime being undef). Fractional times are supported if the underlying 647and $mtime being undef). Fractional times are supported if the underlying
702syscalls support them. 648syscalls support them.
703 649
704When called with a pathname, uses utimes(2) if available, otherwise 650When called with a pathname, uses utimensat(2) or utimes(2) if available,
705utime(2). If called on a file descriptor, uses futimes(2) if available, 651otherwise utime(2). If called on a file descriptor, uses futimens(2)
706otherwise returns ENOSYS, so this is not portable. 652or futimes(2) if available, otherwise returns ENOSYS, so this is not
653portable.
707 654
708Examples: 655Examples:
709 656
710 # set atime and mtime to current time (basically touch(1)): 657 # set atime and mtime to current time (basically touch(1)):
711 aio_utime "path", undef, undef; 658 aio_utime "path", undef, undef;
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739C<$mode> is usually C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> to allocate 686C<$mode> is usually C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> to allocate
740space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE | IO::AIO::FALLOC_FL_KEEP_SIZE>, 687space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE | IO::AIO::FALLOC_FL_KEEP_SIZE>,
741to deallocate a file range. 688to deallocate a file range.
742 689
743IO::AIO also supports C<FALLOC_FL_COLLAPSE_RANGE>, to remove a range 690IO::AIO also supports C<FALLOC_FL_COLLAPSE_RANGE>, to remove a range
744(without leaving a hole) and C<FALLOC_FL_ZERO_RANGE>, to zero a range (see 691(without leaving a hole), C<FALLOC_FL_ZERO_RANGE>, to zero a range,
745your L<fallocate(2)> manpage). 692C<FALLOC_FL_INSERT_RANGE> to insert a range and C<FALLOC_FL_UNSHARE_RANGE>
693to unshare shared blocks (see your L<fallocate(2)> manpage).
746 694
747The file system block size used by C<fallocate> is presumably the 695The file system block size used by C<fallocate> is presumably the
748C<f_bsize> returned by C<statvfs>. 696C<f_bsize> returned by C<statvfs>, but different filesystems and filetypes
697can dictate other limitations.
749 698
750If C<fallocate> isn't available or cannot be emulated (currently no 699If C<fallocate> isn't available or cannot be emulated (currently no
751emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>. 700emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>.
752 701
753 702
… …
812On systems that support the AIO::WD working directory abstraction 761On systems that support the AIO::WD working directory abstraction
813natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead 762natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead
814of failing, C<rename> is called on the absolute path of C<$wd>. 763of failing, C<rename> is called on the absolute path of C<$wd>.
815 764
816 765
766=item aio_rename2 $srcpath, $dstpath, $flags, $callback->($status)
767
768Basically a version of C<aio_rename> with an additional C<$flags>
769argument. Calling this with C<$flags=0> is the same as calling
770C<aio_rename>.
771
772Non-zero flags are currently only supported on GNU/Linux systems that
773support renameat2. Other systems fail with C<ENOSYS> in this case.
774
775The following constants are available (missing ones are, as usual C<0>),
776see renameat2(2) for details:
777
778C<IO::AIO::RENAME_NOREPLACE>, C<IO::AIO::RENAME_EXCHANGE>
779and C<IO::AIO::RENAME_WHITEOUT>.
780
781
817=item aio_mkdir $pathname, $mode, $callback->($status) 782=item aio_mkdir $pathname, $mode, $callback->($status)
818 783
819Asynchronously mkdir (create) a directory and call the callback with 784Asynchronously mkdir (create) a directory and call the callback with
820the result code. C<$mode> will be modified by the umask at the time the 785the result code. C<$mode> will be modified by the umask at the time the
821request is executed, so do not change your umask. 786request is executed, so do not change your umask.
… …
852 817
853=over 4 818=over 4
854 819
855=item IO::AIO::READDIR_DENTS 820=item IO::AIO::READDIR_DENTS
856 821
857When this flag is off, then the callback gets an arrayref consisting of 822Normally the callback gets an arrayref consisting of names only (as
858names only (as with C<aio_readdir>), otherwise it gets an arrayref with 823with C<aio_readdir>). If this flag is set, then the callback gets an
859C<[$name, $type, $inode]> arrayrefs, each describing a single directory 824arrayref with C<[$name, $type, $inode]> arrayrefs, each describing a
860entry in more detail. 825single directory entry in more detail:
861 826
862C<$name> is the name of the entry. 827C<$name> is the name of the entry.
863 828
864C<$type> is one of the C<IO::AIO::DT_xxx> constants: 829C<$type> is one of the C<IO::AIO::DT_xxx> constants:
865 830
866C<IO::AIO::DT_UNKNOWN>, C<IO::AIO::DT_FIFO>, C<IO::AIO::DT_CHR>, C<IO::AIO::DT_DIR>, 831C<IO::AIO::DT_UNKNOWN>, C<IO::AIO::DT_FIFO>, C<IO::AIO::DT_CHR>, C<IO::AIO::DT_DIR>,
867C<IO::AIO::DT_BLK>, C<IO::AIO::DT_REG>, C<IO::AIO::DT_LNK>, C<IO::AIO::DT_SOCK>, 832C<IO::AIO::DT_BLK>, C<IO::AIO::DT_REG>, C<IO::AIO::DT_LNK>, C<IO::AIO::DT_SOCK>,
868C<IO::AIO::DT_WHT>. 833C<IO::AIO::DT_WHT>.
869 834
870C<IO::AIO::DT_UNKNOWN> means just that: readdir does not know. If you need to 835C<IO::AIO::DT_UNKNOWN> means just that: readdir does not know. If you need
871know, you have to run stat yourself. Also, for speed reasons, the C<$type> 836to know, you have to run stat yourself. Also, for speed/memory reasons,
872scalars are read-only: you can not modify them. 837the C<$type> scalars are read-only: you must not modify them.
873 838
874C<$inode> is the inode number (which might not be exact on systems with 64 839C<$inode> is the inode number (which might not be exact on systems with 64
875bit inode numbers and 32 bit perls). This field has unspecified content on 840bit inode numbers and 32 bit perls). This field has unspecified content on
876systems that do not deliver the inode information. 841systems that do not deliver the inode information.
877 842
… …
888short names are tried first. 853short names are tried first.
889 854
890=item IO::AIO::READDIR_STAT_ORDER 855=item IO::AIO::READDIR_STAT_ORDER
891 856
892When this flag is set, then the names will be returned in an order 857When this flag is set, then the names will be returned in an order
893suitable for stat()'ing each one. That is, when you plan to stat() 858suitable for stat()'ing each one. That is, when you plan to stat() most or
894all files in the given directory, then the returned order will likely 859all files in the given directory, then the returned order will likely be
895be fastest. 860faster.
896 861
897If both this flag and C<IO::AIO::READDIR_DIRS_FIRST> are specified, then 862If both this flag and C<IO::AIO::READDIR_DIRS_FIRST> are specified,
898the likely dirs come first, resulting in a less optimal stat order. 863then the likely dirs come first, resulting in a less optimal stat order
864for stat'ing all entries, but likely a more optimal order for finding
865subdirectories.
899 866
900=item IO::AIO::READDIR_FOUND_UNKNOWN 867=item IO::AIO::READDIR_FOUND_UNKNOWN
901 868
902This flag should not be set when calling C<aio_readdirx>. Instead, it 869This flag should not be set when calling C<aio_readdirx>. Instead, it
903is being set by C<aio_readdirx>, when any of the C<$type>'s found were 870is being set by C<aio_readdirx>, when any of the C<$type>'s found were
… …
905C<$type>'s are known, which can be used to speed up some algorithms. 872C<$type>'s are known, which can be used to speed up some algorithms.
906 873
907=back 874=back
908 875
909 876
877=item aio_slurp $pathname, $offset, $length, $data, $callback->($status)
878
879Opens, reads and closes the given file. The data is put into C<$data>,
880which is resized as required.
881
882If C<$offset> is negative, then it is counted from the end of the file.
883
884If C<$length> is zero, then the remaining length of the file is
885used. Also, in this case, the same limitations to modifying C<$data> apply
886as when IO::AIO::mmap is used, i.e. it must only be modified in-place
887with C<substr>. If the size of the file is known, specifying a non-zero
888C<$length> results in a performance advantage.
889
890This request is similar to the older C<aio_load> request, but since it is
891a single request, it might be more efficient to use.
892
893Example: load F</etc/passwd> into C<$passwd>.
894
895 my $passwd;
896 aio_slurp "/etc/passwd", 0, 0, $passwd, sub {
897 $_[0] >= 0
898 or die "/etc/passwd: $!\n";
899
900 printf "/etc/passwd is %d bytes long, and contains:\n", length $passwd;
901 print $passwd;
902 };
903 IO::AIO::flush;
904
905
910=item aio_load $pathname, $data, $callback->($status) 906=item aio_load $pathname, $data, $callback->($status)
911 907
912This is a composite request that tries to fully load the given file into 908This is a composite request that tries to fully load the given file into
913memory. Status is the same as with aio_read. 909memory. Status is the same as with aio_read.
910
911Using C<aio_slurp> might be more efficient, as it is a single request.
914 912
915=cut 913=cut
916 914
917sub aio_load($$;$) { 915sub aio_load($$;$) {
918 my ($path, undef, $cb) = @_; 916 my ($path, undef, $cb) = @_;
… …
938=item aio_copy $srcpath, $dstpath, $callback->($status) 936=item aio_copy $srcpath, $dstpath, $callback->($status)
939 937
940Try to copy the I<file> (directories not supported as either source or 938Try to copy the I<file> (directories not supported as either source or
941destination) from C<$srcpath> to C<$dstpath> and call the callback with 939destination) from C<$srcpath> to C<$dstpath> and call the callback with
942a status of C<0> (ok) or C<-1> (error, see C<$!>). 940a status of C<0> (ok) or C<-1> (error, see C<$!>).
941
942Existing destination files will be truncated.
943 943
944This is a composite request that creates the destination file with 944This is a composite request that creates the destination file with
945mode 0200 and copies the contents of the source file into it using 945mode 0200 and copies the contents of the source file into it using
946C<aio_sendfile>, followed by restoring atime, mtime, access mode and 946C<aio_sendfile>, followed by restoring atime, mtime, access mode and
947uid/gid, in that order. 947uid/gid, in that order.
… …
1057Scans a directory (similar to C<aio_readdir>) but additionally tries to 1057Scans a directory (similar to C<aio_readdir>) but additionally tries to
1058efficiently separate the entries of directory C<$path> into two sets of 1058efficiently separate the entries of directory C<$path> into two sets of
1059names, directories you can recurse into (directories), and ones you cannot 1059names, directories you can recurse into (directories), and ones you cannot
1060recurse into (everything else, including symlinks to directories). 1060recurse into (everything else, including symlinks to directories).
1061 1061
1062C<aio_scandir> is a composite request that creates of many sub requests_ 1062C<aio_scandir> is a composite request that generates many sub requests.
1063C<$maxreq> specifies the maximum number of outstanding aio requests that 1063C<$maxreq> specifies the maximum number of outstanding aio requests that
1064this function generates. If it is C<< <= 0 >>, then a suitable default 1064this function generates. If it is C<< <= 0 >>, then a suitable default
1065will be chosen (currently 4). 1065will be chosen (currently 4).
1066 1066
1067On error, the callback is called without arguments, otherwise it receives 1067On error, the callback is called without arguments, otherwise it receives
… …
1131 aioreq_pri $pri; 1131 aioreq_pri $pri;
1132 add $grp aio_stat $wd, sub { 1132 add $grp aio_stat $wd, sub {
1133 return $grp->result () if $_[0]; 1133 return $grp->result () if $_[0];
1134 my $now = time; 1134 my $now = time;
1135 my $hash1 = join ":", (stat _)[0,1,3,7,9]; 1135 my $hash1 = join ":", (stat _)[0,1,3,7,9];
1136 my $rdxflags = READDIR_DIRS_FIRST;
1137
1138 if ((stat _)[3] < 2) {
1139 # at least one non-POSIX filesystem exists
1140 # that returns useful DT_type values: btrfs,
1141 # so optimise for this here by requesting dents
1142 $rdxflags |= READDIR_DENTS;
1143 }
1136 1144
1137 # read the directory entries 1145 # read the directory entries
1138 aioreq_pri $pri; 1146 aioreq_pri $pri;
1139 add $grp aio_readdirx $wd, READDIR_DIRS_FIRST, sub { 1147 add $grp aio_readdirx $wd, $rdxflags, sub {
1140 my $entries = shift 1148 my ($entries, $flags) = @_
1141 or return $grp->result (); 1149 or return $grp->result ();
1150
1151 if ($rdxflags & READDIR_DENTS) {
1152 # if we requested type values, see if we can use them directly.
1153
1154 # if there were any DT_UNKNOWN entries then we assume we
1155 # don't know. alternatively, we could assume that if we get
1156 # one DT_DIR, then all directories are indeed marked with
1157 # DT_DIR, but this seems not required for btrfs, and this
1158 # is basically the "btrfs can't get it's act together" code
1159 # branch.
1160 unless ($flags & READDIR_FOUND_UNKNOWN) {
1161 # now we have valid DT_ information for all entries,
1162 # so use it as an optimisation without further stat's.
1163 # they must also all be at the beginning of @$entries
1164 # by now.
1165
1166 my $dirs;
1167
1168 if (@$entries) {
1169 for (0 .. $#$entries) {
1170 if ($entries->[$_][1] != DT_DIR) {
1171 # splice out directories
1172 $dirs = [splice @$entries, 0, $_];
1173 last;
1174 }
1175 }
1176
1177 # if we didn't find any non-dir, then all entries are dirs
1178 unless ($dirs) {
1179 ($dirs, $entries) = ($entries, []);
1180 }
1181 } else {
1182 # directory is empty, so there are no sbdirs
1183 $dirs = [];
1184 }
1185
1186 # either splice'd the directories out or the dir was empty.
1187 # convert dents to filenames
1188 $_ = $_->[0] for @$dirs;
1189 $_ = $_->[0] for @$entries;
1190
1191 return $grp->result ($dirs, $entries);
1192 }
1193
1194 # cannot use, so return to our old ways
1195 # by pretending we only scanned for names.
1196 $_ = $_->[0] for @$entries;
1197 }
1142 1198
1143 # stat the dir another time 1199 # stat the dir another time
1144 aioreq_pri $pri; 1200 aioreq_pri $pri;
1145 add $grp aio_stat $wd, sub { 1201 add $grp aio_stat $wd, sub {
1146 my $hash2 = join ":", (stat _)[0,1,3,7,9]; 1202 my $hash2 = join ":", (stat _)[0,1,3,7,9];
… …
1254other processes), although if you are careful and know what you are doing, 1310other processes), although if you are careful and know what you are doing,
1255you still can. 1311you still can.
1256 1312
1257The following constants are available (missing ones are, as usual C<0>): 1313The following constants are available (missing ones are, as usual C<0>):
1258 1314
1315C<F_DUPFD_CLOEXEC>,
1316
1317C<F_OFD_GETLK>, C<F_OFD_SETLK>, C<F_OFD_GETLKW>,
1318
1259C<FIFREEZE>, C<FITHAW>, C<FITRIM>, C<FICLONE>, C<FICLONERANGE>, C<FIDEDUPERANGE>. 1319C<FIFREEZE>, C<FITHAW>, C<FITRIM>, C<FICLONE>, C<FICLONERANGE>, C<FIDEDUPERANGE>.
1260 1320
1261C<FS_IOC_GETFLAGS>, C<FS_IOC_SETFLAGS>, C<FS_IOC_GETVERSION>, C<FS_IOC_SETVERSION>, 1321C<FS_IOC_GETFLAGS>, C<FS_IOC_SETFLAGS>, C<FS_IOC_GETVERSION>, C<FS_IOC_SETVERSION>,
1262C<FS_IOC_FIEMAP>. 1322C<FS_IOC_FIEMAP>.
1263 1323
… …
1350 }; 1410 };
1351 1411
1352 $grp 1412 $grp
1353} 1413}
1354 1414
1355=item aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) 1415=item aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status)
1356 1416
1357This is a rather advanced IO::AIO call, which only works on mmap(2)ed 1417This is a rather advanced IO::AIO call, which only works on mmap(2)ed
1358scalars (see the C<IO::AIO::mmap> function, although it also works on data 1418scalars (see the C<IO::AIO::mmap> function, although it also works on data
1359scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the 1419scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the
1360scalar must only be modified in-place while an aio operation is pending on 1420scalar must only be modified in-place while an aio operation is pending on
… …
1362 1422
1363It calls the C<msync> function of your OS, if available, with the memory 1423It calls the C<msync> function of your OS, if available, with the memory
1364area starting at C<$offset> in the string and ending C<$length> bytes 1424area starting at C<$offset> in the string and ending C<$length> bytes
1365later. If C<$length> is negative, counts from the end, and if C<$length> 1425later. If C<$length> is negative, counts from the end, and if C<$length>
1366is C<undef>, then it goes till the end of the string. The flags can be 1426is C<undef>, then it goes till the end of the string. The flags can be
1367a combination of C<IO::AIO::MS_ASYNC>, C<IO::AIO::MS_INVALIDATE> and 1427either C<IO::AIO::MS_ASYNC> or C<IO::AIO::MS_SYNC>, plus an optional
1368C<IO::AIO::MS_SYNC>. 1428C<IO::AIO::MS_INVALIDATE>.
1369 1429
1370=item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) 1430=item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
1371 1431
1372This is a rather advanced IO::AIO call, which works best on mmap(2)ed 1432This is a rather advanced IO::AIO call, which works best on mmap(2)ed
1373scalars. 1433scalars.
… …
1403 IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh; 1463 IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh;
1404 aio_mlock $data; # mlock in background 1464 aio_mlock $data; # mlock in background
1405 1465
1406=item aio_mlockall $flags, $callback->($status) 1466=item aio_mlockall $flags, $callback->($status)
1407 1467
1408Calls the C<mlockall> function with the given C<$flags> (a combination of 1468Calls the C<mlockall> function with the given C<$flags> (a
1409C<IO::AIO::MCL_CURRENT> and C<IO::AIO::MCL_FUTURE>). 1469combination of C<IO::AIO::MCL_CURRENT>, C<IO::AIO::MCL_FUTURE> and
1470C<IO::AIO::MCL_ONFAULT>).
1410 1471
1411On systems that do not implement C<mlockall>, this function returns C<-1> 1472On systems that do not implement C<mlockall>, this function returns C<-1>
1412and sets errno to C<ENOSYS>. 1473and sets errno to C<ENOSYS>. Similarly, flag combinations not supported
1474by the system result in a return value of C<-1> with errno being set to
1475C<EINVAL>.
1413 1476
1414Note that the corresponding C<munlockall> is synchronous and is 1477Note that the corresponding C<munlockall> is synchronous and is
1415documented under L<MISCELLANEOUS FUNCTIONS>. 1478documented under L<MISCELLANEOUS FUNCTIONS>.
1416 1479
1417Example: asynchronously lock all current and future pages into memory. 1480Example: asynchronously lock all current and future pages into memory.
… …
1456C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>, 1519C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>,
1457C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>, 1520C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>,
1458C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or 1521C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or
1459C<IO::AIO::FIEMAP_EXTENT_SHARED>. 1522C<IO::AIO::FIEMAP_EXTENT_SHARED>.
1460 1523
1461At the time of this writing (Linux 3.2), this requets is unreliable unless 1524At the time of this writing (Linux 3.2), this request is unreliable unless
1462C<$count> is C<undef>, as the kernel has all sorts of bugs preventing 1525C<$count> is C<undef>, as the kernel has all sorts of bugs preventing
1463it to return all extents of a range for files with large number of 1526it to return all extents of a range for files with a large number of
1464extents. The code works around all these issues if C<$count> is undef. 1527extents. The code (only) works around all these issues if C<$count> is
1528C<undef>.
1465 1529
1466=item aio_group $callback->(...) 1530=item aio_group $callback->(...)
1467 1531
1468This is a very special aio request: Instead of doing something, it is a 1532This is a very special aio request: Instead of doing something, it is a
1469container for other aio requests, which is useful if you want to bundle 1533container for other aio requests, which is useful if you want to bundle
… …
1582There are some caveats: when directories get renamed (or deleted), the 1646There are some caveats: when directories get renamed (or deleted), the
1583pathname string doesn't change, so will point to the new directory (or 1647pathname string doesn't change, so will point to the new directory (or
1584nowhere at all), while the directory fd, if available on the system, 1648nowhere at all), while the directory fd, if available on the system,
1585will still point to the original directory. Most functions accepting a 1649will still point to the original directory. Most functions accepting a
1586pathname will use the directory fd on newer systems, and the string on 1650pathname will use the directory fd on newer systems, and the string on
1587older systems. Some functions (such as realpath) will always rely on the 1651older systems. Some functions (such as C<aio_realpath>) will always rely on
1588string form of the pathname. 1652the string form of the pathname.
1589 1653
1590So this functionality is mainly useful to get some protection against 1654So this functionality is mainly useful to get some protection against
1591C<chdir>, to easily get an absolute path out of a relative path for future 1655C<chdir>, to easily get an absolute path out of a relative path for future
1592reference, and to speed up doing many operations in the same directory 1656reference, and to speed up doing many operations in the same directory
1593(e.g. when stat'ing all files in a directory). 1657(e.g. when stat'ing all files in a directory).
… …
1801The default value for the limit is C<0>, but note that setting a feeder 1865The default value for the limit is C<0>, but note that setting a feeder
1802automatically bumps it up to C<2>. 1866automatically bumps it up to C<2>.
1803 1867
1804=back 1868=back
1805 1869
1870
1806=head2 SUPPORT FUNCTIONS 1871=head2 SUPPORT FUNCTIONS
1807 1872
1808=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION 1873=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION
1809 1874
1810=over 4 1875=over 4
… …
1875Strictly equivalent to: 1940Strictly equivalent to:
1876 1941
1877 IO::AIO::poll_wait, IO::AIO::poll_cb 1942 IO::AIO::poll_wait, IO::AIO::poll_cb
1878 while IO::AIO::nreqs; 1943 while IO::AIO::nreqs;
1879 1944
1945This function can be useful at program aborts, to make sure outstanding
1946I/O has been done (C<IO::AIO> uses an C<END> block which already calls
1947this function on normal exits), or when you are merely using C<IO::AIO>
1948for its more advanced functions, rather than for async I/O, e.g.:
1949
1950 my ($dirs, $nondirs);
1951 IO::AIO::aio_scandir "/tmp", 0, sub { ($dirs, $nondirs) = @_ };
1952 IO::AIO::flush;
1953 # $dirs, $nondirs are now set
1954
1880=item IO::AIO::max_poll_reqs $nreqs 1955=item IO::AIO::max_poll_reqs $nreqs
1881 1956
1882=item IO::AIO::max_poll_time $seconds 1957=item IO::AIO::max_poll_time $seconds
1883 1958
1884These set the maximum number of requests (default C<0>, meaning infinity) 1959These set the maximum number of requests (default C<0>, meaning infinity)
… …
1910 poll => 'r', nice => 1, 1985 poll => 'r', nice => 1,
1911 cb => &IO::AIO::poll_cb); 1986 cb => &IO::AIO::poll_cb);
1912 1987
1913=back 1988=back
1914 1989
1990
1915=head3 CONTROLLING THE NUMBER OF THREADS 1991=head3 CONTROLLING THE NUMBER OF THREADS
1916 1992
1917=over 1993=over
1918 1994
1919=item IO::AIO::min_parallel $nthreads 1995=item IO::AIO::min_parallel $nthreads
… …
1985This is a very bad function to use in interactive programs because it 2061This is a very bad function to use in interactive programs because it
1986blocks, and a bad way to reduce concurrency because it is inexact: Better 2062blocks, and a bad way to reduce concurrency because it is inexact: Better
1987use an C<aio_group> together with a feed callback. 2063use an C<aio_group> together with a feed callback.
1988 2064
1989Its main use is in scripts without an event loop - when you want to stat 2065Its main use is in scripts without an event loop - when you want to stat
1990a lot of files, you can write somehting like this: 2066a lot of files, you can write something like this:
1991 2067
1992 IO::AIO::max_outstanding 32; 2068 IO::AIO::max_outstanding 32;
1993 2069
1994 for my $path (...) { 2070 for my $path (...) {
1995 aio_stat $path , ...; 2071 aio_stat $path , ...;
… …
2006The default value for C<max_outstanding> is very large, so there is no 2082The default value for C<max_outstanding> is very large, so there is no
2007practical limit on the number of outstanding requests. 2083practical limit on the number of outstanding requests.
2008 2084
2009=back 2085=back
2010 2086
2087
2011=head3 STATISTICAL INFORMATION 2088=head3 STATISTICAL INFORMATION
2012 2089
2013=over 2090=over
2014 2091
2015=item IO::AIO::nreqs 2092=item IO::AIO::nreqs
… …
2031 2108
2032Returns the number of requests currently in the pending state (executed, 2109Returns the number of requests currently in the pending state (executed,
2033but not yet processed by poll_cb). 2110but not yet processed by poll_cb).
2034 2111
2035=back 2112=back
2113
2114
2115=head3 SUBSECOND STAT TIME ACCESS
2116
2117Both C<aio_stat>/C<aio_lstat> and perl's C<stat>/C<lstat> functions can
2118generally find access/modification and change times with subsecond time
2119accuracy of the system supports it, but perl's built-in functions only
2120return the integer part.
2121
2122The following functions return the timestamps of the most recent
2123stat with subsecond precision on most systems and work both after
2124C<aio_stat>/C<aio_lstat> and perl's C<stat>/C<lstat> calls. Their return
2125value is only meaningful after a successful C<stat>/C<lstat> call, or
2126during/after a successful C<aio_stat>/C<aio_lstat> callback.
2127
2128This is similar to the L<Time::HiRes> C<stat> functions, but can return
2129full resolution without rounding and work with standard perl C<stat>,
2130alleviating the need to call the special C<Time::HiRes> functions, which
2131do not act like their perl counterparts.
2132
2133On operating systems or file systems where subsecond time resolution is
2134not supported or could not be detected, a fractional part of C<0> is
2135returned, so it is always safe to call these functions.
2136
2137=over 4
2138
2139=item $seconds = IO::AIO::st_atime, IO::AIO::st_mtime, IO::AIO::st_ctime, IO::AIO::st_btime
2140
2141Return the access, modication, change or birth time, respectively,
2142including fractional part. Due to the limited precision of floating point,
2143the accuracy on most platforms is only a bit better than milliseconds
2144for times around now - see the I<nsec> function family, below, for full
2145accuracy.
2146
2147File birth time is only available when the OS and perl support it (on
2148FreeBSD and NetBSD at the time of this writing, although support is
2149adaptive, so if your OS/perl gains support, IO::AIO can take advantage of
2150it). On systems where it isn't available, C<0> is currently returned, but
2151this might change to C<undef> in a future version.
2152
2153=item ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtime
2154
2155Returns access, modification, change and birth time all in one go, and
2156maybe more times in the future version.
2157
2158=item $nanoseconds = IO::AIO::st_atimensec, IO::AIO::st_mtimensec, IO::AIO::st_ctimensec, IO::AIO::st_btimensec
2159
2160Return the fractional access, modifcation, change or birth time, in nanoseconds,
2161as an integer in the range C<0> to C<999999999>.
2162
2163Note that no accessors are provided for access, modification and
2164change times - you need to get those from C<stat _> if required (C<int
2165IO::AIO::st_atime> and so on will I<not> generally give you the correct
2166value).
2167
2168=item $seconds = IO::AIO::st_btimesec
2169
2170The (integral) seconds part of the file birth time, if available.
2171
2172=item ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtimensec
2173
2174Like the functions above, but returns all four times in one go (and maybe
2175more in future versions).
2176
2177=item $counter = IO::AIO::st_gen
2178
2179Returns the generation counter (in practice this is just a random number)
2180of the file. This is only available on platforms which have this member in
2181their C<struct stat> (most BSDs at the time of this writing) and generally
2182only to the root usert. If unsupported, C<0> is returned, but this might
2183change to C<undef> in a future version.
2184
2185=back
2186
2187Example: print the high resolution modification time of F</etc>, using
2188C<stat>, and C<IO::AIO::aio_stat>.
2189
2190 if (stat "/etc") {
2191 printf "stat(/etc) mtime: %f\n", IO::AIO::st_mtime;
2192 }
2193
2194 IO::AIO::aio_stat "/etc", sub {
2195 $_[0]
2196 and return;
2197
2198 printf "aio_stat(/etc) mtime: %d.%09d\n", (stat _)[9], IO::AIO::st_mtimensec;
2199 };
2200
2201 IO::AIO::flush;
2202
2203Output of the awbove on my system, showing reduced and full accuracy:
2204
2205 stat(/etc) mtime: 1534043702.020808
2206 aio_stat(/etc) mtime: 1534043702.020807792
2207
2036 2208
2037=head3 MISCELLANEOUS FUNCTIONS 2209=head3 MISCELLANEOUS FUNCTIONS
2038 2210
2039IO::AIO implements some functions that are useful when you want to use 2211IO::AIO implements some functions that are useful when you want to use
2040some "Advanced I/O" function not available to in Perl, without going the 2212some "Advanced I/O" function not available to in Perl, without going the
2041"Asynchronous I/O" route. Many of these have an asynchronous C<aio_*> 2213"Asynchronous I/O" route. Many of these have an asynchronous C<aio_*>
2042counterpart. 2214counterpart.
2043 2215
2044=over 4 2216=over 4
2217
2218=item $numfd = IO::AIO::get_fdlimit
2219
2220This function is I<EXPERIMENTAL> and subject to change.
2221
2222Tries to find the current file descriptor limit and returns it, or
2223C<undef> and sets C<$!> in case of an error. The limit is one larger than
2224the highest valid file descriptor number.
2225
2226=item IO::AIO::min_fdlimit [$numfd]
2227
2228This function is I<EXPERIMENTAL> and subject to change.
2229
2230Try to increase the current file descriptor limit(s) to at least C<$numfd>
2231by changing the soft or hard file descriptor resource limit. If C<$numfd>
2232is missing, it will try to set a very high limit, although this is not
2233recommended when you know the actual minimum that you require.
2234
2235If the limit cannot be raised enough, the function makes a best-effort
2236attempt to increase the limit as much as possible, using various
2237tricks, while still failing. You can query the resulting limit using
2238C<IO::AIO::get_fdlimit>.
2239
2240If an error occurs, returns C<undef> and sets C<$!>, otherwise returns
2241true.
2045 2242
2046=item IO::AIO::sendfile $ofh, $ifh, $offset, $count 2243=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
2047 2244
2048Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>, 2245Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>,
2049but is blocking (this makes most sense if you know the input data is 2246but is blocking (this makes most sense if you know the input data is
… …
2066=item IO::AIO::madvise $scalar, $offset, $len, $advice 2263=item IO::AIO::madvise $scalar, $offset, $len, $advice
2067 2264
2068Simply calls the C<posix_madvise> function (see its 2265Simply calls the C<posix_madvise> function (see its
2069manpage for details). The following advice constants are 2266manpage for details). The following advice constants are
2070available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>, 2267available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,
2071C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>, 2268C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>,
2072C<IO::AIO::MADV_FREE>. 2269C<IO::AIO::MADV_DONTNEED>.
2270
2271If C<$offset> is negative, counts from the end. If C<$length> is negative,
2272the remaining length of the C<$scalar> is used. If possible, C<$length>
2273will be reduced to fit into the C<$scalar>.
2073 2274
2074On systems that do not implement C<posix_madvise>, this function returns 2275On systems that do not implement C<posix_madvise>, this function returns
2075ENOSYS, otherwise the return value of C<posix_madvise>. 2276ENOSYS, otherwise the return value of C<posix_madvise>.
2076 2277
2077=item IO::AIO::mprotect $scalar, $offset, $len, $protect 2278=item IO::AIO::mprotect $scalar, $offset, $len, $protect
… …
2079Simply calls the C<mprotect> function on the preferably AIO::mmap'ed 2280Simply calls the C<mprotect> function on the preferably AIO::mmap'ed
2080$scalar (see its manpage for details). The following protect 2281$scalar (see its manpage for details). The following protect
2081constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>, 2282constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,
2082C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>. 2283C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.
2083 2284
2285If C<$offset> is negative, counts from the end. If C<$length> is negative,
2286the remaining length of the C<$scalar> is used. If possible, C<$length>
2287will be reduced to fit into the C<$scalar>.
2288
2084On systems that do not implement C<mprotect>, this function returns 2289On systems that do not implement C<mprotect>, this function returns
2085ENOSYS, otherwise the return value of C<mprotect>. 2290ENOSYS, otherwise the return value of C<mprotect>.
2086 2291
2087=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] 2292=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]
2088 2293
2089Memory-maps a file (or anonymous memory range) and attaches it to the 2294Memory-maps a file (or anonymous memory range) and attaches it to the
2090given C<$scalar>, which will act like a string scalar. Returns true on 2295given C<$scalar>, which will act like a string scalar. Returns true on
2091success, and false otherwise. 2296success, and false otherwise.
2092 2297
2298The scalar must exist, but its contents do not matter - this means you
2299cannot use a nonexistant array or hash element. When in doubt, C<undef>
2300the scalar first.
2301
2093The only operations allowed on the scalar are C<substr>/C<vec> that don't 2302The only operations allowed on the mmapped scalar are C<substr>/C<vec>,
2094change the string length, and most read-only operations such as copying it 2303which don't change the string length, and most read-only operations such
2095or searching it with regexes and so on. 2304as copying it or searching it with regexes and so on.
2096 2305
2097Anything else is unsafe and will, at best, result in memory leaks. 2306Anything else is unsafe and will, at best, result in memory leaks.
2098 2307
2099The memory map associated with the C<$scalar> is automatically removed 2308The memory map associated with the C<$scalar> is automatically removed
2100when the C<$scalar> is destroyed, or when the C<IO::AIO::mmap> or 2309when the C<$scalar> is undef'd or destroyed, or when the C<IO::AIO::mmap>
2101C<IO::AIO::munmap> functions are called. 2310or C<IO::AIO::munmap> functions are called on it.
2102 2311
2103This calls the C<mmap>(2) function internally. See your system's manual 2312This calls the C<mmap>(2) function internally. See your system's manual
2104page for details on the C<$length>, C<$prot> and C<$flags> parameters. 2313page for details on the C<$length>, C<$prot> and C<$flags> parameters.
2105 2314
2106The C<$length> must be larger than zero and smaller than the actual 2315The C<$length> must be larger than zero and smaller than the actual
… …
2144 2353
2145=item IO::AIO::munmap $scalar 2354=item IO::AIO::munmap $scalar
2146 2355
2147Removes a previous mmap and undefines the C<$scalar>. 2356Removes a previous mmap and undefines the C<$scalar>.
2148 2357
2358=item IO::AIO::mremap $scalar, $new_length, $flags = MREMAP_MAYMOVE[, $new_address = 0]
2359
2360Calls the Linux-specific mremap(2) system call. The C<$scalar> must have
2361been mapped by C<IO::AIO::mmap>, and C<$flags> must currently either be
2362C<0> or C<IO::AIO::MREMAP_MAYMOVE>.
2363
2364Returns true if successful, and false otherwise. If the underlying mmapped
2365region has changed address, then the true value has the numerical value
2366C<1>, otherwise it has the numerical value C<0>:
2367
2368 my $success = IO::AIO::mremap $mmapped, 8192, IO::AIO::MREMAP_MAYMOVE
2369 or die "mremap: $!";
2370
2371 if ($success*1) {
2372 warn "scalar has chanegd address in memory\n";
2373 }
2374
2375C<IO::AIO::MREMAP_FIXED> and the C<$new_address> argument are currently
2376implemented, but not supported and might go away in a future version.
2377
2378On systems where this call is not supported or is not emulated, this call
2379returns falls and sets C<$!> to C<ENOSYS>.
2380
2381=item IO::AIO::mlockall $flags
2382
2383Calls the C<eio_mlockall_sync> function, which is like C<aio_mlockall>,
2384but is blocking.
2385
2149=item IO::AIO::munlock $scalar, $offset = 0, $length = undef 2386=item IO::AIO::munlock $scalar, $offset = 0, $length = undef
2150 2387
2151Calls the C<munlock> function, undoing the effects of a previous 2388Calls the C<munlock> function, undoing the effects of a previous
2152C<aio_mlock> call (see its description for details). 2389C<aio_mlock> call (see its description for details).
2153 2390
… …
2202C<$flags> is non-zero, fails with C<ENOSYS>. 2439C<$flags> is non-zero, fails with C<ENOSYS>.
2203 2440
2204Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the 2441Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the
2205time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and 2442time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and
2206C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported. 2443C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported.
2444
2445Example: create a pipe race-free w.r.t. threads and fork:
2446
2447 my ($rfh, $wfh) = IO::AIO::pipe2 IO::AIO::O_CLOEXEC
2448 or die "pipe2: $!\n";
2449
2450=item $fh = IO::AIO::memfd_create $pathname[, $flags]
2451
2452This is a direct interface to the Linux L<memfd_create(2)> system
2453call. The (unhelpful) default for C<$flags> is C<0>, but your default
2454should be C<IO::AIO::MFD_CLOEXEC>.
2455
2456On success, the new memfd filehandle is returned, otherwise returns
2457C<undef>. If the memfd_create syscall is missing, fails with C<ENOSYS>.
2458
2459Please refer to L<memfd_create(2)> for more info on this call.
2460
2461The following C<$flags> values are available: C<IO::AIO::MFD_CLOEXEC>,
2462C<IO::AIO::MFD_ALLOW_SEALING> and C<IO::AIO::MFD_HUGETLB>.
2463
2464Example: create a new memfd.
2465
2466 my $fh = IO::AIO::memfd_create "somenameforprocfd", IO::AIO::MFD_CLOEXEC
2467 or die "m,emfd_create: $!\n";
2468=item $fh = IO::AIO::eventfd [$initval, [$flags]]
2469
2470This is a direct interface to the Linux L<eventfd(2)> system call. The
2471(unhelpful) defaults for C<$initval> and C<$flags> are C<0> for both.
2472
2473On success, the new eventfd filehandle is returned, otherwise returns
2474C<undef>. If the eventfd syscall is missing, fails with C<ENOSYS>.
2475
2476Please refer to L<eventfd(2)> for more info on this call.
2477
2478The following symbol flag values are available: C<IO::AIO::EFD_CLOEXEC>,
2479C<IO::AIO::EFD_NONBLOCK> and C<IO::AIO::EFD_SEMAPHORE> (Linux 2.6.30).
2480
2481Example: create a new eventfd filehandle:
2482
2483 $fh = IO::AIO::eventfd 0, IO::AIO::EFD_CLOEXEC
2484 or die "eventfd: $!\n";
2485
2486=item $fh = IO::AIO::timerfd_create $clockid[, $flags]
2487
2488This is a direct interface to the Linux L<timerfd_create(2)> system
2489call. The (unhelpful) default for C<$flags> is C<0>, but your default
2490should be C<IO::AIO::TFD_CLOEXEC>.
2491
2492On success, the new timerfd filehandle is returned, otherwise returns
2493C<undef>. If the timerfd_create syscall is missing, fails with C<ENOSYS>.
2494
2495Please refer to L<timerfd_create(2)> for more info on this call.
2496
2497The following C<$clockid> values are
2498available: C<IO::AIO::CLOCK_REALTIME>, C<IO::AIO::CLOCK_MONOTONIC>
2499C<IO::AIO::CLOCK_CLOCK_BOOTTIME> (Linux 3.15)
2500C<IO::AIO::CLOCK_CLOCK_REALTIME_ALARM> (Linux 3.11) and
2501C<IO::AIO::CLOCK_CLOCK_BOOTTIME_ALARM> (Linux 3.11).
2502
2503The following C<$flags> values are available (Linux
25042.6.27): C<IO::AIO::TFD_NONBLOCK> and C<IO::AIO::TFD_CLOEXEC>.
2505
2506Example: create a new timerfd and set it to one-second repeated alarms,
2507then wait for two alarms:
2508
2509 my $fh = IO::AIO::timerfd_create IO::AIO::CLOCK_BOOTTIME, IO::AIO::TFD_CLOEXEC
2510 or die "timerfd_create: $!\n";
2511
2512 defined IO::AIO::timerfd_settime $fh, 0, 1, 1
2513 or die "timerfd_settime: $!\n";
2514
2515 for (1..2) {
2516 8 == sysread $fh, my $buf, 8
2517 or die "timerfd read failure\n";
2518
2519 printf "number of expirations (likely 1): %d\n",
2520 unpack "Q", $buf;
2521 }
2522
2523=item ($cur_interval, $cur_value) = IO::AIO::timerfd_settime $fh, $flags, $new_interval, $nbw_value
2524
2525This is a direct interface to the Linux L<timerfd_settime(2)> system
2526call. Please refer to its manpage for more info on this call.
2527
2528The new itimerspec is specified using two (possibly fractional) second
2529values, C<$new_interval> and C<$new_value>).
2530
2531On success, the current interval and value are returned (as per
2532C<timerfd_gettime>). On failure, the empty list is returned.
2533
2534The following C<$flags> values are
2535available: C<IO::AIO::TFD_TIMER_ABSTIME> and
2536C<IO::AIO::TFD_TIMER_CANCEL_ON_SET>.
2537
2538See C<IO::AIO::timerfd_create> for a full example.
2539
2540=item ($cur_interval, $cur_value) = IO::AIO::timerfd_gettime $fh
2541
2542This is a direct interface to the Linux L<timerfd_gettime(2)> system
2543call. Please refer to its manpage for more info on this call.
2544
2545On success, returns the current values of interval and value for the given
2546timerfd (as potentially fractional second values). On failure, the empty
2547list is returned.
2207 2548
2208=back 2549=back
2209 2550
2210=cut 2551=cut
2211 2552
… …
2277the process will result in undefined behaviour. Calling it at any time 2618the process will result in undefined behaviour. Calling it at any time
2278will also result in any undefined (by POSIX) behaviour. 2619will also result in any undefined (by POSIX) behaviour.
2279 2620
2280=back 2621=back
2281 2622
2623=head2 LINUX-SPECIFIC CALLS
2624
2625When a call is documented as "linux-specific" then this means it
2626originated on GNU/Linux. C<IO::AIO> will usually try to autodetect the
2627availability and compatibility of such calls regardless of the platform
2628it is compiled on, so platforms such as FreeBSD which often implement
2629these calls will work. When in doubt, call them and see if they fail wth
2630C<ENOSYS>.
2631
2282=head2 MEMORY USAGE 2632=head2 MEMORY USAGE
2283 2633
2284Per-request usage: 2634Per-request usage:
2285 2635
2286Each aio request uses - depending on your architecture - around 100-200 2636Each aio request uses - depending on your architecture - around 100-200
… …
2298temporary buffers, and each thread requires a stack and other data 2648temporary buffers, and each thread requires a stack and other data
2299structures (usually around 16k-128k, depending on the OS). 2649structures (usually around 16k-128k, depending on the OS).
2300 2650
2301=head1 KNOWN BUGS 2651=head1 KNOWN BUGS
2302 2652
2303Known bugs will be fixed in the next release. 2653Known bugs will be fixed in the next release :)
2654
2655=head1 KNOWN ISSUES
2656
2657Calls that try to "import" foreign memory areas (such as C<IO::AIO::mmap>
2658or C<IO::AIO::aio_slurp>) do not work with generic lvalues, such as
2659non-created hash slots or other scalars I didn't think of. It's best to
2660avoid such and either use scalar variables or making sure that the scalar
2661exists (e.g. by storing C<undef>) and isn't "funny" (e.g. tied).
2662
2663I am not sure anything can be done about this, so this is considered a
2664known issue, rather than a bug.
2304 2665
2305=head1 SEE ALSO 2666=head1 SEE ALSO
2306 2667
2307L<AnyEvent::AIO> for easy integration into event loops, L<Coro::AIO> for a 2668L<AnyEvent::AIO> for easy integration into event loops, L<Coro::AIO> for a
2308more natural syntax. 2669more natural syntax.

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