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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 1.304 by root, Wed Apr 3 03:11:45 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];
… …
1252So in general, you should only use these calls for things that do 1308So in general, you should only use these calls for things that do
1253(filesystem) I/O, not for things that wait for other events (network, 1309(filesystem) I/O, not for things that wait for other events (network,
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 and can be used for normal C<ioctl>
1314and C<fcntl> as well (missing ones are, as usual C<0>):
1315
1316C<F_DUPFD_CLOEXEC>,
1317
1318C<F_OFD_GETLK>, C<F_OFD_SETLK>, C<F_OFD_GETLKW>,
1258 1319
1259C<FIFREEZE>, C<FITHAW>, C<FITRIM>, C<FICLONE>, C<FICLONERANGE>, C<FIDEDUPERANGE>. 1320C<FIFREEZE>, C<FITHAW>, C<FITRIM>, C<FICLONE>, C<FICLONERANGE>, C<FIDEDUPERANGE>.
1321
1322C<F_ADD_SEALS>, C<F_GET_SEALS>, C<F_SEAL_SEAL>, C<F_SEAL_SHRINK>, C<F_SEAL_GROW> and
1323C<F_SEAL_WRITE>.
1260 1324
1261C<FS_IOC_GETFLAGS>, C<FS_IOC_SETFLAGS>, C<FS_IOC_GETVERSION>, C<FS_IOC_SETVERSION>, 1325C<FS_IOC_GETFLAGS>, C<FS_IOC_SETFLAGS>, C<FS_IOC_GETVERSION>, C<FS_IOC_SETVERSION>,
1262C<FS_IOC_FIEMAP>. 1326C<FS_IOC_FIEMAP>.
1263 1327
1264C<FS_IOC_FSGETXATTR>, C<FS_IOC_FSSETXATTR>, C<FS_IOC_SET_ENCRYPTION_POLICY>, 1328C<FS_IOC_FSGETXATTR>, C<FS_IOC_FSSETXATTR>, C<FS_IOC_SET_ENCRYPTION_POLICY>,
… …
1350 }; 1414 };
1351 1415
1352 $grp 1416 $grp
1353} 1417}
1354 1418
1355=item aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) 1419=item aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status)
1356 1420
1357This is a rather advanced IO::AIO call, which only works on mmap(2)ed 1421This 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 1422scalars (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 1423scalars 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 1424scalar must only be modified in-place while an aio operation is pending on
… …
1362 1426
1363It calls the C<msync> function of your OS, if available, with the memory 1427It 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 1428area 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> 1429later. 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 1430is 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 1431either C<IO::AIO::MS_ASYNC> or C<IO::AIO::MS_SYNC>, plus an optional
1368C<IO::AIO::MS_SYNC>. 1432C<IO::AIO::MS_INVALIDATE>.
1369 1433
1370=item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) 1434=item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
1371 1435
1372This is a rather advanced IO::AIO call, which works best on mmap(2)ed 1436This is a rather advanced IO::AIO call, which works best on mmap(2)ed
1373scalars. 1437scalars.
… …
1403 IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh; 1467 IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh;
1404 aio_mlock $data; # mlock in background 1468 aio_mlock $data; # mlock in background
1405 1469
1406=item aio_mlockall $flags, $callback->($status) 1470=item aio_mlockall $flags, $callback->($status)
1407 1471
1408Calls the C<mlockall> function with the given C<$flags> (a combination of 1472Calls the C<mlockall> function with the given C<$flags> (a
1409C<IO::AIO::MCL_CURRENT> and C<IO::AIO::MCL_FUTURE>). 1473combination of C<IO::AIO::MCL_CURRENT>, C<IO::AIO::MCL_FUTURE> and
1474C<IO::AIO::MCL_ONFAULT>).
1410 1475
1411On systems that do not implement C<mlockall>, this function returns C<-1> 1476On systems that do not implement C<mlockall>, this function returns C<-1>
1412and sets errno to C<ENOSYS>. 1477and sets errno to C<ENOSYS>. Similarly, flag combinations not supported
1478by the system result in a return value of C<-1> with errno being set to
1479C<EINVAL>.
1413 1480
1414Note that the corresponding C<munlockall> is synchronous and is 1481Note that the corresponding C<munlockall> is synchronous and is
1415documented under L<MISCELLANEOUS FUNCTIONS>. 1482documented under L<MISCELLANEOUS FUNCTIONS>.
1416 1483
1417Example: asynchronously lock all current and future pages into memory. 1484Example: asynchronously lock all current and future pages into memory.
… …
1456C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>, 1523C<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>, 1524C<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 1525C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or
1459C<IO::AIO::FIEMAP_EXTENT_SHARED>. 1526C<IO::AIO::FIEMAP_EXTENT_SHARED>.
1460 1527
1461At the time of this writing (Linux 3.2), this requets is unreliable unless 1528At the time of this writing (Linux 3.2), this request is unreliable unless
1462C<$count> is C<undef>, as the kernel has all sorts of bugs preventing 1529C<$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 1530it to return all extents of a range for files with a large number of
1464extents. The code works around all these issues if C<$count> is undef. 1531extents. The code (only) works around all these issues if C<$count> is
1532C<undef>.
1465 1533
1466=item aio_group $callback->(...) 1534=item aio_group $callback->(...)
1467 1535
1468This is a very special aio request: Instead of doing something, it is a 1536This 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 1537container for other aio requests, which is useful if you want to bundle
… …
1582There are some caveats: when directories get renamed (or deleted), the 1650There are some caveats: when directories get renamed (or deleted), the
1583pathname string doesn't change, so will point to the new directory (or 1651pathname string doesn't change, so will point to the new directory (or
1584nowhere at all), while the directory fd, if available on the system, 1652nowhere at all), while the directory fd, if available on the system,
1585will still point to the original directory. Most functions accepting a 1653will still point to the original directory. Most functions accepting a
1586pathname will use the directory fd on newer systems, and the string on 1654pathname will use the directory fd on newer systems, and the string on
1587older systems. Some functions (such as realpath) will always rely on the 1655older systems. Some functions (such as C<aio_realpath>) will always rely on
1588string form of the pathname. 1656the string form of the pathname.
1589 1657
1590So this functionality is mainly useful to get some protection against 1658So 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 1659C<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 1660reference, and to speed up doing many operations in the same directory
1593(e.g. when stat'ing all files in a directory). 1661(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 1869The default value for the limit is C<0>, but note that setting a feeder
1802automatically bumps it up to C<2>. 1870automatically bumps it up to C<2>.
1803 1871
1804=back 1872=back
1805 1873
1874
1806=head2 SUPPORT FUNCTIONS 1875=head2 SUPPORT FUNCTIONS
1807 1876
1808=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION 1877=head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION
1809 1878
1810=over 4 1879=over 4
… …
1875Strictly equivalent to: 1944Strictly equivalent to:
1876 1945
1877 IO::AIO::poll_wait, IO::AIO::poll_cb 1946 IO::AIO::poll_wait, IO::AIO::poll_cb
1878 while IO::AIO::nreqs; 1947 while IO::AIO::nreqs;
1879 1948
1949This function can be useful at program aborts, to make sure outstanding
1950I/O has been done (C<IO::AIO> uses an C<END> block which already calls
1951this function on normal exits), or when you are merely using C<IO::AIO>
1952for its more advanced functions, rather than for async I/O, e.g.:
1953
1954 my ($dirs, $nondirs);
1955 IO::AIO::aio_scandir "/tmp", 0, sub { ($dirs, $nondirs) = @_ };
1956 IO::AIO::flush;
1957 # $dirs, $nondirs are now set
1958
1880=item IO::AIO::max_poll_reqs $nreqs 1959=item IO::AIO::max_poll_reqs $nreqs
1881 1960
1882=item IO::AIO::max_poll_time $seconds 1961=item IO::AIO::max_poll_time $seconds
1883 1962
1884These set the maximum number of requests (default C<0>, meaning infinity) 1963These set the maximum number of requests (default C<0>, meaning infinity)
… …
1910 poll => 'r', nice => 1, 1989 poll => 'r', nice => 1,
1911 cb => &IO::AIO::poll_cb); 1990 cb => &IO::AIO::poll_cb);
1912 1991
1913=back 1992=back
1914 1993
1994
1915=head3 CONTROLLING THE NUMBER OF THREADS 1995=head3 CONTROLLING THE NUMBER OF THREADS
1916 1996
1917=over 1997=over
1918 1998
1919=item IO::AIO::min_parallel $nthreads 1999=item IO::AIO::min_parallel $nthreads
… …
1985This is a very bad function to use in interactive programs because it 2065This 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 2066blocks, and a bad way to reduce concurrency because it is inexact: Better
1987use an C<aio_group> together with a feed callback. 2067use an C<aio_group> together with a feed callback.
1988 2068
1989Its main use is in scripts without an event loop - when you want to stat 2069Its main use is in scripts without an event loop - when you want to stat
1990a lot of files, you can write somehting like this: 2070a lot of files, you can write something like this:
1991 2071
1992 IO::AIO::max_outstanding 32; 2072 IO::AIO::max_outstanding 32;
1993 2073
1994 for my $path (...) { 2074 for my $path (...) {
1995 aio_stat $path , ...; 2075 aio_stat $path , ...;
… …
2006The default value for C<max_outstanding> is very large, so there is no 2086The default value for C<max_outstanding> is very large, so there is no
2007practical limit on the number of outstanding requests. 2087practical limit on the number of outstanding requests.
2008 2088
2009=back 2089=back
2010 2090
2091
2011=head3 STATISTICAL INFORMATION 2092=head3 STATISTICAL INFORMATION
2012 2093
2013=over 2094=over
2014 2095
2015=item IO::AIO::nreqs 2096=item IO::AIO::nreqs
… …
2031 2112
2032Returns the number of requests currently in the pending state (executed, 2113Returns the number of requests currently in the pending state (executed,
2033but not yet processed by poll_cb). 2114but not yet processed by poll_cb).
2034 2115
2035=back 2116=back
2117
2118
2119=head3 SUBSECOND STAT TIME ACCESS
2120
2121Both C<aio_stat>/C<aio_lstat> and perl's C<stat>/C<lstat> functions can
2122generally find access/modification and change times with subsecond time
2123accuracy of the system supports it, but perl's built-in functions only
2124return the integer part.
2125
2126The following functions return the timestamps of the most recent
2127stat with subsecond precision on most systems and work both after
2128C<aio_stat>/C<aio_lstat> and perl's C<stat>/C<lstat> calls. Their return
2129value is only meaningful after a successful C<stat>/C<lstat> call, or
2130during/after a successful C<aio_stat>/C<aio_lstat> callback.
2131
2132This is similar to the L<Time::HiRes> C<stat> functions, but can return
2133full resolution without rounding and work with standard perl C<stat>,
2134alleviating the need to call the special C<Time::HiRes> functions, which
2135do not act like their perl counterparts.
2136
2137On operating systems or file systems where subsecond time resolution is
2138not supported or could not be detected, a fractional part of C<0> is
2139returned, so it is always safe to call these functions.
2140
2141=over 4
2142
2143=item $seconds = IO::AIO::st_atime, IO::AIO::st_mtime, IO::AIO::st_ctime, IO::AIO::st_btime
2144
2145Return the access, modication, change or birth time, respectively,
2146including fractional part. Due to the limited precision of floating point,
2147the accuracy on most platforms is only a bit better than milliseconds
2148for times around now - see the I<nsec> function family, below, for full
2149accuracy.
2150
2151File birth time is only available when the OS and perl support it (on
2152FreeBSD and NetBSD at the time of this writing, although support is
2153adaptive, so if your OS/perl gains support, IO::AIO can take advantage of
2154it). On systems where it isn't available, C<0> is currently returned, but
2155this might change to C<undef> in a future version.
2156
2157=item ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtime
2158
2159Returns access, modification, change and birth time all in one go, and
2160maybe more times in the future version.
2161
2162=item $nanoseconds = IO::AIO::st_atimensec, IO::AIO::st_mtimensec, IO::AIO::st_ctimensec, IO::AIO::st_btimensec
2163
2164Return the fractional access, modifcation, change or birth time, in nanoseconds,
2165as an integer in the range C<0> to C<999999999>.
2166
2167Note that no accessors are provided for access, modification and
2168change times - you need to get those from C<stat _> if required (C<int
2169IO::AIO::st_atime> and so on will I<not> generally give you the correct
2170value).
2171
2172=item $seconds = IO::AIO::st_btimesec
2173
2174The (integral) seconds part of the file birth time, if available.
2175
2176=item ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtimensec
2177
2178Like the functions above, but returns all four times in one go (and maybe
2179more in future versions).
2180
2181=item $counter = IO::AIO::st_gen
2182
2183Returns the generation counter (in practice this is just a random number)
2184of the file. This is only available on platforms which have this member in
2185their C<struct stat> (most BSDs at the time of this writing) and generally
2186only to the root usert. If unsupported, C<0> is returned, but this might
2187change to C<undef> in a future version.
2188
2189=back
2190
2191Example: print the high resolution modification time of F</etc>, using
2192C<stat>, and C<IO::AIO::aio_stat>.
2193
2194 if (stat "/etc") {
2195 printf "stat(/etc) mtime: %f\n", IO::AIO::st_mtime;
2196 }
2197
2198 IO::AIO::aio_stat "/etc", sub {
2199 $_[0]
2200 and return;
2201
2202 printf "aio_stat(/etc) mtime: %d.%09d\n", (stat _)[9], IO::AIO::st_mtimensec;
2203 };
2204
2205 IO::AIO::flush;
2206
2207Output of the awbove on my system, showing reduced and full accuracy:
2208
2209 stat(/etc) mtime: 1534043702.020808
2210 aio_stat(/etc) mtime: 1534043702.020807792
2211
2036 2212
2037=head3 MISCELLANEOUS FUNCTIONS 2213=head3 MISCELLANEOUS FUNCTIONS
2038 2214
2039IO::AIO implements some functions that are useful when you want to use 2215IO::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 2216some "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_*> 2217"Asynchronous I/O" route. Many of these have an asynchronous C<aio_*>
2042counterpart. 2218counterpart.
2043 2219
2044=over 4 2220=over 4
2221
2222=item $numfd = IO::AIO::get_fdlimit
2223
2224This function is I<EXPERIMENTAL> and subject to change.
2225
2226Tries to find the current file descriptor limit and returns it, or
2227C<undef> and sets C<$!> in case of an error. The limit is one larger than
2228the highest valid file descriptor number.
2229
2230=item IO::AIO::min_fdlimit [$numfd]
2231
2232This function is I<EXPERIMENTAL> and subject to change.
2233
2234Try to increase the current file descriptor limit(s) to at least C<$numfd>
2235by changing the soft or hard file descriptor resource limit. If C<$numfd>
2236is missing, it will try to set a very high limit, although this is not
2237recommended when you know the actual minimum that you require.
2238
2239If the limit cannot be raised enough, the function makes a best-effort
2240attempt to increase the limit as much as possible, using various
2241tricks, while still failing. You can query the resulting limit using
2242C<IO::AIO::get_fdlimit>.
2243
2244If an error occurs, returns C<undef> and sets C<$!>, otherwise returns
2245true.
2045 2246
2046=item IO::AIO::sendfile $ofh, $ifh, $offset, $count 2247=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
2047 2248
2048Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>, 2249Calls 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 2250but is blocking (this makes most sense if you know the input data is
… …
2066=item IO::AIO::madvise $scalar, $offset, $len, $advice 2267=item IO::AIO::madvise $scalar, $offset, $len, $advice
2067 2268
2068Simply calls the C<posix_madvise> function (see its 2269Simply calls the C<posix_madvise> function (see its
2069manpage for details). The following advice constants are 2270manpage for details). The following advice constants are
2070available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>, 2271available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>,
2071C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>, 2272C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>,
2072C<IO::AIO::MADV_FREE>. 2273C<IO::AIO::MADV_DONTNEED>.
2274
2275If C<$offset> is negative, counts from the end. If C<$length> is negative,
2276the remaining length of the C<$scalar> is used. If possible, C<$length>
2277will be reduced to fit into the C<$scalar>.
2073 2278
2074On systems that do not implement C<posix_madvise>, this function returns 2279On systems that do not implement C<posix_madvise>, this function returns
2075ENOSYS, otherwise the return value of C<posix_madvise>. 2280ENOSYS, otherwise the return value of C<posix_madvise>.
2076 2281
2077=item IO::AIO::mprotect $scalar, $offset, $len, $protect 2282=item IO::AIO::mprotect $scalar, $offset, $len, $protect
… …
2079Simply calls the C<mprotect> function on the preferably AIO::mmap'ed 2284Simply calls the C<mprotect> function on the preferably AIO::mmap'ed
2080$scalar (see its manpage for details). The following protect 2285$scalar (see its manpage for details). The following protect
2081constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>, 2286constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>,
2082C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>. 2287C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>.
2083 2288
2289If C<$offset> is negative, counts from the end. If C<$length> is negative,
2290the remaining length of the C<$scalar> is used. If possible, C<$length>
2291will be reduced to fit into the C<$scalar>.
2292
2084On systems that do not implement C<mprotect>, this function returns 2293On systems that do not implement C<mprotect>, this function returns
2085ENOSYS, otherwise the return value of C<mprotect>. 2294ENOSYS, otherwise the return value of C<mprotect>.
2086 2295
2087=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] 2296=item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]
2088 2297
2089Memory-maps a file (or anonymous memory range) and attaches it to the 2298Memory-maps a file (or anonymous memory range) and attaches it to the
2090given C<$scalar>, which will act like a string scalar. Returns true on 2299given C<$scalar>, which will act like a string scalar. Returns true on
2091success, and false otherwise. 2300success, and false otherwise.
2092 2301
2302The scalar must exist, but its contents do not matter - this means you
2303cannot use a nonexistant array or hash element. When in doubt, C<undef>
2304the scalar first.
2305
2093The only operations allowed on the scalar are C<substr>/C<vec> that don't 2306The only operations allowed on the mmapped scalar are C<substr>/C<vec>,
2094change the string length, and most read-only operations such as copying it 2307which don't change the string length, and most read-only operations such
2095or searching it with regexes and so on. 2308as copying it or searching it with regexes and so on.
2096 2309
2097Anything else is unsafe and will, at best, result in memory leaks. 2310Anything else is unsafe and will, at best, result in memory leaks.
2098 2311
2099The memory map associated with the C<$scalar> is automatically removed 2312The memory map associated with the C<$scalar> is automatically removed
2100when the C<$scalar> is destroyed, or when the C<IO::AIO::mmap> or 2313when the C<$scalar> is undef'd or destroyed, or when the C<IO::AIO::mmap>
2101C<IO::AIO::munmap> functions are called. 2314or C<IO::AIO::munmap> functions are called on it.
2102 2315
2103This calls the C<mmap>(2) function internally. See your system's manual 2316This calls the C<mmap>(2) function internally. See your system's manual
2104page for details on the C<$length>, C<$prot> and C<$flags> parameters. 2317page for details on the C<$length>, C<$prot> and C<$flags> parameters.
2105 2318
2106The C<$length> must be larger than zero and smaller than the actual 2319The C<$length> must be larger than zero and smaller than the actual
… …
2144 2357
2145=item IO::AIO::munmap $scalar 2358=item IO::AIO::munmap $scalar
2146 2359
2147Removes a previous mmap and undefines the C<$scalar>. 2360Removes a previous mmap and undefines the C<$scalar>.
2148 2361
2362=item IO::AIO::mremap $scalar, $new_length, $flags = MREMAP_MAYMOVE[, $new_address = 0]
2363
2364Calls the Linux-specific mremap(2) system call. The C<$scalar> must have
2365been mapped by C<IO::AIO::mmap>, and C<$flags> must currently either be
2366C<0> or C<IO::AIO::MREMAP_MAYMOVE>.
2367
2368Returns true if successful, and false otherwise. If the underlying mmapped
2369region has changed address, then the true value has the numerical value
2370C<1>, otherwise it has the numerical value C<0>:
2371
2372 my $success = IO::AIO::mremap $mmapped, 8192, IO::AIO::MREMAP_MAYMOVE
2373 or die "mremap: $!";
2374
2375 if ($success*1) {
2376 warn "scalar has chanegd address in memory\n";
2377 }
2378
2379C<IO::AIO::MREMAP_FIXED> and the C<$new_address> argument are currently
2380implemented, but not supported and might go away in a future version.
2381
2382On systems where this call is not supported or is not emulated, this call
2383returns falls and sets C<$!> to C<ENOSYS>.
2384
2385=item IO::AIO::mlockall $flags
2386
2387Calls the C<eio_mlockall_sync> function, which is like C<aio_mlockall>,
2388but is blocking.
2389
2149=item IO::AIO::munlock $scalar, $offset = 0, $length = undef 2390=item IO::AIO::munlock $scalar, $offset = 0, $length = undef
2150 2391
2151Calls the C<munlock> function, undoing the effects of a previous 2392Calls the C<munlock> function, undoing the effects of a previous
2152C<aio_mlock> call (see its description for details). 2393C<aio_mlock> call (see its description for details).
2153 2394
… …
2202C<$flags> is non-zero, fails with C<ENOSYS>. 2443C<$flags> is non-zero, fails with C<ENOSYS>.
2203 2444
2204Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the 2445Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the
2205time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and 2446time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and
2206C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported. 2447C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported.
2448
2449Example: create a pipe race-free w.r.t. threads and fork:
2450
2451 my ($rfh, $wfh) = IO::AIO::pipe2 IO::AIO::O_CLOEXEC
2452 or die "pipe2: $!\n";
2453
2454=item $fh = IO::AIO::memfd_create $pathname[, $flags]
2455
2456This is a direct interface to the Linux L<memfd_create(2)> system
2457call. The (unhelpful) default for C<$flags> is C<0>, but your default
2458should be C<IO::AIO::MFD_CLOEXEC>.
2459
2460On success, the new memfd filehandle is returned, otherwise returns
2461C<undef>. If the memfd_create syscall is missing, fails with C<ENOSYS>.
2462
2463Please refer to L<memfd_create(2)> for more info on this call.
2464
2465The following C<$flags> values are available: C<IO::AIO::MFD_CLOEXEC>,
2466C<IO::AIO::MFD_ALLOW_SEALING> and C<IO::AIO::MFD_HUGETLB>.
2467
2468Example: create a new memfd.
2469
2470 my $fh = IO::AIO::memfd_create "somenameforprocfd", IO::AIO::MFD_CLOEXEC
2471 or die "m,emfd_create: $!\n";
2472=item $fh = IO::AIO::eventfd [$initval, [$flags]]
2473
2474This is a direct interface to the Linux L<eventfd(2)> system call. The
2475(unhelpful) defaults for C<$initval> and C<$flags> are C<0> for both.
2476
2477On success, the new eventfd filehandle is returned, otherwise returns
2478C<undef>. If the eventfd syscall is missing, fails with C<ENOSYS>.
2479
2480Please refer to L<eventfd(2)> for more info on this call.
2481
2482The following symbol flag values are available: C<IO::AIO::EFD_CLOEXEC>,
2483C<IO::AIO::EFD_NONBLOCK> and C<IO::AIO::EFD_SEMAPHORE> (Linux 2.6.30).
2484
2485Example: create a new eventfd filehandle:
2486
2487 $fh = IO::AIO::eventfd 0, IO::AIO::EFD_CLOEXEC
2488 or die "eventfd: $!\n";
2489
2490=item $fh = IO::AIO::timerfd_create $clockid[, $flags]
2491
2492This is a direct interface to the Linux L<timerfd_create(2)> system
2493call. The (unhelpful) default for C<$flags> is C<0>, but your default
2494should be C<IO::AIO::TFD_CLOEXEC>.
2495
2496On success, the new timerfd filehandle is returned, otherwise returns
2497C<undef>. If the timerfd_create syscall is missing, fails with C<ENOSYS>.
2498
2499Please refer to L<timerfd_create(2)> for more info on this call.
2500
2501The following C<$clockid> values are
2502available: C<IO::AIO::CLOCK_REALTIME>, C<IO::AIO::CLOCK_MONOTONIC>
2503C<IO::AIO::CLOCK_CLOCK_BOOTTIME> (Linux 3.15)
2504C<IO::AIO::CLOCK_CLOCK_REALTIME_ALARM> (Linux 3.11) and
2505C<IO::AIO::CLOCK_CLOCK_BOOTTIME_ALARM> (Linux 3.11).
2506
2507The following C<$flags> values are available (Linux
25082.6.27): C<IO::AIO::TFD_NONBLOCK> and C<IO::AIO::TFD_CLOEXEC>.
2509
2510Example: create a new timerfd and set it to one-second repeated alarms,
2511then wait for two alarms:
2512
2513 my $fh = IO::AIO::timerfd_create IO::AIO::CLOCK_BOOTTIME, IO::AIO::TFD_CLOEXEC
2514 or die "timerfd_create: $!\n";
2515
2516 defined IO::AIO::timerfd_settime $fh, 0, 1, 1
2517 or die "timerfd_settime: $!\n";
2518
2519 for (1..2) {
2520 8 == sysread $fh, my $buf, 8
2521 or die "timerfd read failure\n";
2522
2523 printf "number of expirations (likely 1): %d\n",
2524 unpack "Q", $buf;
2525 }
2526
2527=item ($cur_interval, $cur_value) = IO::AIO::timerfd_settime $fh, $flags, $new_interval, $nbw_value
2528
2529This is a direct interface to the Linux L<timerfd_settime(2)> system
2530call. Please refer to its manpage for more info on this call.
2531
2532The new itimerspec is specified using two (possibly fractional) second
2533values, C<$new_interval> and C<$new_value>).
2534
2535On success, the current interval and value are returned (as per
2536C<timerfd_gettime>). On failure, the empty list is returned.
2537
2538The following C<$flags> values are
2539available: C<IO::AIO::TFD_TIMER_ABSTIME> and
2540C<IO::AIO::TFD_TIMER_CANCEL_ON_SET>.
2541
2542See C<IO::AIO::timerfd_create> for a full example.
2543
2544=item ($cur_interval, $cur_value) = IO::AIO::timerfd_gettime $fh
2545
2546This is a direct interface to the Linux L<timerfd_gettime(2)> system
2547call. Please refer to its manpage for more info on this call.
2548
2549On success, returns the current values of interval and value for the given
2550timerfd (as potentially fractional second values). On failure, the empty
2551list is returned.
2207 2552
2208=back 2553=back
2209 2554
2210=cut 2555=cut
2211 2556
… …
2277the process will result in undefined behaviour. Calling it at any time 2622the process will result in undefined behaviour. Calling it at any time
2278will also result in any undefined (by POSIX) behaviour. 2623will also result in any undefined (by POSIX) behaviour.
2279 2624
2280=back 2625=back
2281 2626
2627=head2 LINUX-SPECIFIC CALLS
2628
2629When a call is documented as "linux-specific" then this means it
2630originated on GNU/Linux. C<IO::AIO> will usually try to autodetect the
2631availability and compatibility of such calls regardless of the platform
2632it is compiled on, so platforms such as FreeBSD which often implement
2633these calls will work. When in doubt, call them and see if they fail wth
2634C<ENOSYS>.
2635
2282=head2 MEMORY USAGE 2636=head2 MEMORY USAGE
2283 2637
2284Per-request usage: 2638Per-request usage:
2285 2639
2286Each aio request uses - depending on your architecture - around 100-200 2640Each aio request uses - depending on your architecture - around 100-200
… …
2298temporary buffers, and each thread requires a stack and other data 2652temporary buffers, and each thread requires a stack and other data
2299structures (usually around 16k-128k, depending on the OS). 2653structures (usually around 16k-128k, depending on the OS).
2300 2654
2301=head1 KNOWN BUGS 2655=head1 KNOWN BUGS
2302 2656
2303Known bugs will be fixed in the next release. 2657Known bugs will be fixed in the next release :)
2658
2659=head1 KNOWN ISSUES
2660
2661Calls that try to "import" foreign memory areas (such as C<IO::AIO::mmap>
2662or C<IO::AIO::aio_slurp>) do not work with generic lvalues, such as
2663non-created hash slots or other scalars I didn't think of. It's best to
2664avoid such and either use scalar variables or making sure that the scalar
2665exists (e.g. by storing C<undef>) and isn't "funny" (e.g. tied).
2666
2667I am not sure anything can be done about this, so this is considered a
2668known issue, rather than a bug.
2304 2669
2305=head1 SEE ALSO 2670=head1 SEE ALSO
2306 2671
2307L<AnyEvent::AIO> for easy integration into event loops, L<Coro::AIO> for a 2672L<AnyEvent::AIO> for easy integration into event loops, L<Coro::AIO> for a
2308more natural syntax. 2673more natural syntax and L<IO::FDPass> for file descriptor passing.
2309 2674
2310=head1 AUTHOR 2675=head1 AUTHOR
2311 2676
2312 Marc Lehmann <schmorp@schmorp.de> 2677 Marc Lehmann <schmorp@schmorp.de>
2313 http://home.schmorp.de/ 2678 http://home.schmorp.de/

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