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2 IO::AIO - Asynchronous Input/Output 2 IO::AIO - Asynchronous Input/Output
3 3
4SYNOPSIS 4SYNOPSIS
5 use IO::AIO; 5 use IO::AIO;
6 6
7 aio_open "/etc/passwd", O_RDONLY, 0, sub { 7 aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub {
8 my $fh = shift 8 my $fh = shift
9 or die "/etc/passwd: $!"; 9 or die "/etc/passwd: $!";
10 ... 10 ...
11 }; 11 };
12 12
24 $req->cancel; # cancel request if still in queue 24 $req->cancel; # cancel request if still in queue
25 25
26 my $grp = aio_group sub { print "all stats done\n" }; 26 my $grp = aio_group sub { print "all stats done\n" };
27 add $grp aio_stat "..." for ...; 27 add $grp aio_stat "..." for ...;
28 28
29 # AnyEvent integration (EV, Event, Glib, Tk, urxvt, pureperl...)
30 open my $fh, "<&=" . IO::AIO::poll_fileno or die "$!";
31 my $w = AnyEvent->io (fh => $fh, poll => 'r', cb => sub { IO::AIO::poll_cb });
32
33 # EV integration
34 my $w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
35
36 # Event integration
37 Event->io (fd => IO::AIO::poll_fileno,
38 poll => 'r',
39 cb => \&IO::AIO::poll_cb);
40
41 # Glib/Gtk2 integration
42 add_watch Glib::IO IO::AIO::poll_fileno,
43 in => sub { IO::AIO::poll_cb; 1 };
44
45 # Tk integration
46 Tk::Event::IO->fileevent (IO::AIO::poll_fileno, "",
47 readable => \&IO::AIO::poll_cb);
48
49 # Danga::Socket integration
50 Danga::Socket->AddOtherFds (IO::AIO::poll_fileno =>
51 \&IO::AIO::poll_cb);
52
53DESCRIPTION 29DESCRIPTION
54 This module implements asynchronous I/O using whatever means your 30 This module implements asynchronous I/O using whatever means your
55 operating system supports. 31 operating system supports. It is implemented as an interface to "libeio"
32 (<http://software.schmorp.de/pkg/libeio.html>).
56 33
57 Asynchronous means that operations that can normally block your program 34 Asynchronous means that operations that can normally block your program
58 (e.g. reading from disk) will be done asynchronously: the operation will 35 (e.g. reading from disk) will be done asynchronously: the operation will
59 still block, but you can do something else in the meantime. This is 36 still block, but you can do something else in the meantime. This is
60 extremely useful for programs that need to stay interactive even when 37 extremely useful for programs that need to stay interactive even when
65 operations concurrently. 42 operations concurrently.
66 43
67 While most of this works on all types of file descriptors (for example 44 While most of this works on all types of file descriptors (for example
68 sockets), using these functions on file descriptors that support 45 sockets), using these functions on file descriptors that support
69 nonblocking operation (again, sockets, pipes etc.) is very inefficient. 46 nonblocking operation (again, sockets, pipes etc.) is very inefficient.
70 Use an event loop for that (such as the Event module): IO::AIO will 47 Use an event loop for that (such as the EV module): IO::AIO will
71 naturally fit into such an event loop itself. 48 naturally fit into such an event loop itself.
72 49
73 In this version, a number of threads are started that execute your 50 In this version, a number of threads are started that execute your
74 requests and signal their completion. You don't need thread support in 51 requests and signal their completion. You don't need thread support in
75 perl, and the threads created by this module will not be visible to 52 perl, and the threads created by this module will not be visible to
84 it is currently not reentrant in any way, so use appropriate locking 61 it is currently not reentrant in any way, so use appropriate locking
85 yourself, always call "poll_cb" from within the same thread, or never 62 yourself, always call "poll_cb" from within the same thread, or never
86 call "poll_cb" (or other "aio_" functions) recursively. 63 call "poll_cb" (or other "aio_" functions) recursively.
87 64
88 EXAMPLE 65 EXAMPLE
89 This is a simple example that uses the Event module and loads 66 This is a simple example that uses the EV module and loads /etc/passwd
90 /etc/passwd asynchronously: 67 asynchronously:
91 68
92 use Fcntl; 69 use Fcntl;
93 use Event; 70 use EV;
94 use IO::AIO; 71 use IO::AIO;
95 72
96 # register the IO::AIO callback with Event 73 # register the IO::AIO callback with EV
97 Event->io (fd => IO::AIO::poll_fileno, 74 my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
98 poll => 'r',
99 cb => \&IO::AIO::poll_cb);
100 75
101 # queue the request to open /etc/passwd 76 # queue the request to open /etc/passwd
102 aio_open "/etc/passwd", O_RDONLY, 0, sub { 77 aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub {
103 my $fh = shift 78 my $fh = shift
104 or die "error while opening: $!"; 79 or die "error while opening: $!";
105 80
106 # stat'ing filehandles is generally non-blocking 81 # stat'ing filehandles is generally non-blocking
107 my $size = -s $fh; 82 my $size = -s $fh;
116 91
117 # file contents now in $contents 92 # file contents now in $contents
118 print $contents; 93 print $contents;
119 94
120 # exit event loop and program 95 # exit event loop and program
121 Event::unloop; 96 EV::unloop;
122 }; 97 };
123 }; 98 };
124 99
125 # possibly queue up other requests, or open GUI windows, 100 # possibly queue up other requests, or open GUI windows,
126 # check for sockets etc. etc. 101 # check for sockets etc. etc.
127 102
128 # process events as long as there are some: 103 # process events as long as there are some:
129 Event::loop; 104 EV::loop;
130 105
131REQUEST ANATOMY AND LIFETIME 106REQUEST ANATOMY AND LIFETIME
132 Every "aio_*" function creates a request. which is a C data structure 107 Every "aio_*" function creates a request. which is a C data structure
133 not directly visible to Perl. 108 not directly visible to Perl.
134 109
170 anymore (except possibly for the Perl object, but its connection to 145 anymore (except possibly for the Perl object, but its connection to
171 the actual aio request is severed and calling its methods will 146 the actual aio request is severed and calling its methods will
172 either do nothing or result in a runtime error). 147 either do nothing or result in a runtime error).
173 148
174FUNCTIONS 149FUNCTIONS
150 QUICK OVERVIEW
151 This section simply lists the prototypes of the most important functions
152 for quick reference. See the following sections for function-by-function
153 documentation.
154
155 aio_open $pathname, $flags, $mode, $callback->($fh)
156 aio_close $fh, $callback->($status)
157 aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
158 aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
159 aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval)
160 aio_readahead $fh,$offset,$length, $callback->($retval)
161 aio_stat $fh_or_path, $callback->($status)
162 aio_lstat $fh, $callback->($status)
163 aio_statvfs $fh_or_path, $callback->($statvfs)
164 aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
165 aio_chown $fh_or_path, $uid, $gid, $callback->($status)
166 aio_truncate $fh_or_path, $offset, $callback->($status)
167 aio_chmod $fh_or_path, $mode, $callback->($status)
168 aio_unlink $pathname, $callback->($status)
169 aio_mknod $path, $mode, $dev, $callback->($status)
170 aio_link $srcpath, $dstpath, $callback->($status)
171 aio_symlink $srcpath, $dstpath, $callback->($status)
172 aio_readlink $path, $callback->($link)
173 aio_rename $srcpath, $dstpath, $callback->($status)
174 aio_mkdir $pathname, $mode, $callback->($status)
175 aio_rmdir $pathname, $callback->($status)
176 aio_readdir $pathname, $callback->($entries)
177 aio_readdirx $pathname, $flags, $callback->($entries, $flags)
178 IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST
179 IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN
180 aio_load $path, $data, $callback->($status)
181 aio_copy $srcpath, $dstpath, $callback->($status)
182 aio_move $srcpath, $dstpath, $callback->($status)
183 aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
184 aio_rmtree $path, $callback->($status)
185 aio_sync $callback->($status)
186 aio_fsync $fh, $callback->($status)
187 aio_fdatasync $fh, $callback->($status)
188 aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
189 aio_pathsync $path, $callback->($status)
190 aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
191 aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
192 aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
193 aio_mlockall $flags, $callback->($status)
194 aio_group $callback->(...)
195 aio_nop $callback->()
196
197 $prev_pri = aioreq_pri [$pri]
198 aioreq_nice $pri_adjust
199
200 IO::AIO::poll_wait
201 IO::AIO::poll_cb
202 IO::AIO::poll
203 IO::AIO::flush
204 IO::AIO::max_poll_reqs $nreqs
205 IO::AIO::max_poll_time $seconds
206 IO::AIO::min_parallel $nthreads
207 IO::AIO::max_parallel $nthreads
208 IO::AIO::max_idle $nthreads
209 IO::AIO::max_outstanding $maxreqs
210 IO::AIO::nreqs
211 IO::AIO::nready
212 IO::AIO::npending
213
214 IO::AIO::sendfile $ofh, $ifh, $offset, $count
215 IO::AIO::fadvise $fh, $offset, $len, $advice
216 IO::AIO::madvise $scalar, $offset, $length, $advice
217 IO::AIO::mprotect $scalar, $offset, $length, $protect
218 IO::AIO::munlock $scalar, $offset = 0, $length = undef
219 IO::AIO::munlockall
220
175 AIO REQUEST FUNCTIONS 221 AIO REQUEST FUNCTIONS
176 All the "aio_*" calls are more or less thin wrappers around the syscall 222 All the "aio_*" calls are more or less thin wrappers around the syscall
177 with the same name (sans "aio_"). The arguments are similar or 223 with the same name (sans "aio_"). The arguments are similar or
178 identical, and they all accept an additional (and optional) $callback 224 identical, and they all accept an additional (and optional) $callback
179 argument which must be a code reference. This code reference will get 225 argument which must be a code reference. This code reference will get
180 called with the syscall return code (e.g. most syscalls return -1 on 226 called with the syscall return code (e.g. most syscalls return -1 on
181 error, unlike perl, which usually delivers "false") as it's sole 227 error, unlike perl, which usually delivers "false") as its sole argument
182 argument when the given syscall has been executed asynchronously. 228 after the given syscall has been executed asynchronously.
183 229
184 All functions expecting a filehandle keep a copy of the filehandle 230 All functions expecting a filehandle keep a copy of the filehandle
185 internally until the request has finished. 231 internally until the request has finished.
186 232
187 All functions return request objects of type IO::AIO::REQ that allow 233 All functions return request objects of type IO::AIO::REQ that allow
200 the user environment, d) use Glib::filename_from_unicode on unicode 246 the user environment, d) use Glib::filename_from_unicode on unicode
201 filenames or e) use something else to ensure your scalar has the correct 247 filenames or e) use something else to ensure your scalar has the correct
202 contents. 248 contents.
203 249
204 This works, btw. independent of the internal UTF-8 bit, which IO::AIO 250 This works, btw. independent of the internal UTF-8 bit, which IO::AIO
205 handles correctly wether it is set or not. 251 handles correctly whether it is set or not.
206 252
207 $prev_pri = aioreq_pri [$pri] 253 $prev_pri = aioreq_pri [$pri]
208 Returns the priority value that would be used for the next request 254 Returns the priority value that would be used for the next request
209 and, if $pri is given, sets the priority for the next aio request. 255 and, if $pri is given, sets the priority for the next aio request.
210 256
250 will be modified by the umask in effect then the request is being 296 will be modified by the umask in effect then the request is being
251 executed, so better never change the umask. 297 executed, so better never change the umask.
252 298
253 Example: 299 Example:
254 300
255 aio_open "/etc/passwd", O_RDONLY, 0, sub { 301 aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub {
256 if ($_[0]) { 302 if ($_[0]) {
257 print "open successful, fh is $_[0]\n"; 303 print "open successful, fh is $_[0]\n";
258 ... 304 ...
259 } else { 305 } else {
260 die "open failed: $!\n"; 306 die "open failed: $!\n";
276 Or in other words: the file descriptor will be closed, but it will 322 Or in other words: the file descriptor will be closed, but it will
277 not be free for reuse until the perl filehandle is closed. 323 not be free for reuse until the perl filehandle is closed.
278 324
279 aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) 325 aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
280 aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) 326 aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval)
281 Reads or writes $length bytes from the specified $fh and $offset 327 Reads or writes $length bytes from or to the specified $fh and
282 into the scalar given by $data and offset $dataoffset and calls the 328 $offset into the scalar given by $data and offset $dataoffset and
283 callback without the actual number of bytes read (or -1 on error, 329 calls the callback without the actual number of bytes read (or -1 on
284 just like the syscall). 330 error, just like the syscall).
331
332 "aio_read" will, like "sysread", shrink or grow the $data scalar to
333 offset plus the actual number of bytes read.
285 334
286 If $offset is undefined, then the current file descriptor offset 335 If $offset is undefined, then the current file descriptor offset
287 will be used (and updated), otherwise the file descriptor offset 336 will be used (and updated), otherwise the file descriptor offset
288 will not be changed by these calls. 337 will not be changed by these calls.
289 338
312 more than one "aio_sendfile" per $out_fh, as they will interfere 361 more than one "aio_sendfile" per $out_fh, as they will interfere
313 with each other. 362 with each other.
314 363
315 This call tries to make use of a native "sendfile" syscall to 364 This call tries to make use of a native "sendfile" syscall to
316 provide zero-copy operation. For this to work, $out_fh should refer 365 provide zero-copy operation. For this to work, $out_fh should refer
317 to a socket, and $in_fh should refer to mmap'able file. 366 to a socket, and $in_fh should refer to an mmap'able file.
318 367
319 If the native sendfile call fails or is not implemented, it will be 368 If a native sendfile cannot be found or it fails with "ENOSYS",
369 "ENOTSUP", "EOPNOTSUPP", "EAFNOSUPPORT", "EPROTOTYPE" or "ENOTSOCK",
320 emulated, so you can call "aio_sendfile" on any type of filehandle 370 it will be emulated, so you can call "aio_sendfile" on any type of
321 regardless of the limitations of the operating system. 371 filehandle regardless of the limitations of the operating system.
322 372
323 Please note, however, that "aio_sendfile" can read more bytes from 373 Please note, however, that "aio_sendfile" can read more bytes from
324 $in_fh than are written, and there is no way to find out how many 374 $in_fh than are written, and there is no way to find out how many
325 bytes have been read from "aio_sendfile" alone, as "aio_sendfile" 375 bytes have been read from "aio_sendfile" alone, as "aio_sendfile"
326 only provides the number of bytes written to $out_fh. Only if the 376 only provides the number of bytes written to $out_fh. Only if the
361 aio_stat "/etc/passwd", sub { 411 aio_stat "/etc/passwd", sub {
362 $_[0] and die "stat failed: $!"; 412 $_[0] and die "stat failed: $!";
363 print "size is ", -s _, "\n"; 413 print "size is ", -s _, "\n";
364 }; 414 };
365 415
416 aio_statvfs $fh_or_path, $callback->($statvfs)
417 Works like the POSIX "statvfs" or "fstatvfs" syscalls, depending on
418 whether a file handle or path was passed.
419
420 On success, the callback is passed a hash reference with the
421 following members: "bsize", "frsize", "blocks", "bfree", "bavail",
422 "files", "ffree", "favail", "fsid", "flag" and "namemax". On
423 failure, "undef" is passed.
424
425 The following POSIX IO::AIO::ST_* constants are defined: "ST_RDONLY"
426 and "ST_NOSUID".
427
428 The following non-POSIX IO::AIO::ST_* flag masks are defined to
429 their correct value when available, or to 0 on systems that do not
430 support them: "ST_NODEV", "ST_NOEXEC", "ST_SYNCHRONOUS",
431 "ST_MANDLOCK", "ST_WRITE", "ST_APPEND", "ST_IMMUTABLE",
432 "ST_NOATIME", "ST_NODIRATIME" and "ST_RELATIME".
433
434 Example: stat "/wd" and dump out the data if successful.
435
436 aio_statvfs "/wd", sub {
437 my $f = $_[0]
438 or die "statvfs: $!";
439
440 use Data::Dumper;
441 say Dumper $f;
442 };
443
444 # result:
445 {
446 bsize => 1024,
447 bfree => 4333064312,
448 blocks => 10253828096,
449 files => 2050765568,
450 flag => 4096,
451 favail => 2042092649,
452 bavail => 4333064312,
453 ffree => 2042092649,
454 namemax => 255,
455 frsize => 1024,
456 fsid => 1810
457 }
458
366 aio_utime $fh_or_path, $atime, $mtime, $callback->($status) 459 aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
367 Works like perl's "utime" function (including the special case of 460 Works like perl's "utime" function (including the special case of
368 $atime and $mtime being undef). Fractional times are supported if 461 $atime and $mtime being undef). Fractional times are supported if
369 the underlying syscalls support them. 462 the underlying syscalls support them.
370 463
440 aio_readdir $pathname, $callback->($entries) 533 aio_readdir $pathname, $callback->($entries)
441 Unlike the POSIX call of the same name, "aio_readdir" reads an 534 Unlike the POSIX call of the same name, "aio_readdir" reads an
442 entire directory (i.e. opendir + readdir + closedir). The entries 535 entire directory (i.e. opendir + readdir + closedir). The entries
443 will not be sorted, and will NOT include the "." and ".." entries. 536 will not be sorted, and will NOT include the "." and ".." entries.
444 537
445 The callback a single argument which is either "undef" or an 538 The callback is passed a single argument which is either "undef" or
446 array-ref with the filenames. 539 an array-ref with the filenames.
540
541 aio_readdirx $pathname, $flags, $callback->($entries, $flags)
542 Quite similar to "aio_readdir", but the $flags argument allows to
543 tune behaviour and output format. In case of an error, $entries will
544 be "undef".
545
546 The flags are a combination of the following constants, ORed
547 together (the flags will also be passed to the callback, possibly
548 modified):
549
550 IO::AIO::READDIR_DENTS
551 When this flag is off, then the callback gets an arrayref with
552 of names only (as with "aio_readdir"), otherwise it gets an
553 arrayref with "[$name, $type, $inode]" arrayrefs, each
554 describing a single directory entry in more detail.
555
556 $name is the name of the entry.
557
558 $type is one of the "IO::AIO::DT_xxx" constants:
559
560 "IO::AIO::DT_UNKNOWN", "IO::AIO::DT_FIFO", "IO::AIO::DT_CHR",
561 "IO::AIO::DT_DIR", "IO::AIO::DT_BLK", "IO::AIO::DT_REG",
562 "IO::AIO::DT_LNK", "IO::AIO::DT_SOCK", "IO::AIO::DT_WHT".
563
564 "IO::AIO::DT_UNKNOWN" means just that: readdir does not know. If
565 you need to know, you have to run stat yourself. Also, for speed
566 reasons, the $type scalars are read-only: you can not modify
567 them.
568
569 $inode is the inode number (which might not be exact on systems
570 with 64 bit inode numbers and 32 bit perls). This field has
571 unspecified content on systems that do not deliver the inode
572 information.
573
574 IO::AIO::READDIR_DIRS_FIRST
575 When this flag is set, then the names will be returned in an
576 order where likely directories come first. This is useful when
577 you need to quickly find directories, or you want to find all
578 directories while avoiding to stat() each entry.
579
580 If the system returns type information in readdir, then this is
581 used to find directories directly. Otherwise, likely directories
582 are files beginning with ".", or otherwise files with no dots,
583 of which files with short names are tried first.
584
585 IO::AIO::READDIR_STAT_ORDER
586 When this flag is set, then the names will be returned in an
587 order suitable for stat()'ing each one. That is, when you plan
588 to stat() all files in the given directory, then the returned
589 order will likely be fastest.
590
591 If both this flag and "IO::AIO::READDIR_DIRS_FIRST" are
592 specified, then the likely dirs come first, resulting in a less
593 optimal stat order.
594
595 IO::AIO::READDIR_FOUND_UNKNOWN
596 This flag should not be set when calling "aio_readdirx".
597 Instead, it is being set by "aio_readdirx", when any of the
598 $type's found were "IO::AIO::DT_UNKNOWN". The absense of this
599 flag therefore indicates that all $type's are known, which can
600 be used to speed up some algorithms.
447 601
448 aio_load $path, $data, $callback->($status) 602 aio_load $path, $data, $callback->($status)
449 This is a composite request that tries to fully load the given file 603 This is a composite request that tries to fully load the given file
450 into memory. Status is the same as with aio_read. 604 into memory. Status is the same as with aio_read.
451 605
452 aio_copy $srcpath, $dstpath, $callback->($status) 606 aio_copy $srcpath, $dstpath, $callback->($status)
453 Try to copy the *file* (directories not supported as either source 607 Try to copy the *file* (directories not supported as either source
454 or destination) from $srcpath to $dstpath and call the callback with 608 or destination) from $srcpath to $dstpath and call the callback with
455 the 0 (error) or -1 ok. 609 a status of 0 (ok) or -1 (error, see $!).
456 610
457 This is a composite request that it creates the destination file 611 This is a composite request that creates the destination file with
458 with mode 0200 and copies the contents of the source file into it 612 mode 0200 and copies the contents of the source file into it using
459 using "aio_sendfile", followed by restoring atime, mtime, access 613 "aio_sendfile", followed by restoring atime, mtime, access mode and
460 mode and uid/gid, in that order. 614 uid/gid, in that order.
461 615
462 If an error occurs, the partial destination file will be unlinked, 616 If an error occurs, the partial destination file will be unlinked,
463 if possible, except when setting atime, mtime, access mode and 617 if possible, except when setting atime, mtime, access mode and
464 uid/gid, where errors are being ignored. 618 uid/gid, where errors are being ignored.
465 619
466 aio_move $srcpath, $dstpath, $callback->($status) 620 aio_move $srcpath, $dstpath, $callback->($status)
467 Try to move the *file* (directories not supported as either source 621 Try to move the *file* (directories not supported as either source
468 or destination) from $srcpath to $dstpath and call the callback with 622 or destination) from $srcpath to $dstpath and call the callback with
469 the 0 (error) or -1 ok. 623 a status of 0 (ok) or -1 (error, see $!).
470 624
471 This is a composite request that tries to rename(2) the file first. 625 This is a composite request that tries to rename(2) the file first;
472 If rename files with "EXDEV", it copies the file with "aio_copy" 626 if rename fails with "EXDEV", it copies the file with "aio_copy"
473 and, if that is successful, unlinking the $srcpath. 627 and, if that is successful, unlinks the $srcpath.
474 628
475 aio_scandir $path, $maxreq, $callback->($dirs, $nondirs) 629 aio_scandir $path, $maxreq, $callback->($dirs, $nondirs)
476 Scans a directory (similar to "aio_readdir") but additionally tries 630 Scans a directory (similar to "aio_readdir") but additionally tries
477 to efficiently separate the entries of directory $path into two sets 631 to efficiently separate the entries of directory $path into two sets
478 of names, directories you can recurse into (directories), and ones 632 of names, directories you can recurse into (directories), and ones
498 Implementation notes. 652 Implementation notes.
499 653
500 The "aio_readdir" cannot be avoided, but "stat()"'ing every entry 654 The "aio_readdir" cannot be avoided, but "stat()"'ing every entry
501 can. 655 can.
502 656
657 If readdir returns file type information, then this is used directly
658 to find directories.
659
503 After reading the directory, the modification time, size etc. of the 660 Otherwise, after reading the directory, the modification time, size
504 directory before and after the readdir is checked, and if they match 661 etc. of the directory before and after the readdir is checked, and
505 (and isn't the current time), the link count will be used to decide 662 if they match (and isn't the current time), the link count will be
506 how many entries are directories (if >= 2). Otherwise, no knowledge 663 used to decide how many entries are directories (if >= 2).
507 of the number of subdirectories will be assumed. 664 Otherwise, no knowledge of the number of subdirectories will be
665 assumed.
508 666
509 Then entries will be sorted into likely directories (everything 667 Then entries will be sorted into likely directories a non-initial
510 without a non-initial dot currently) and likely non-directories 668 dot currently) and likely non-directories (see "aio_readdirx"). Then
511 (everything else). Then every entry plus an appended "/." will be 669 every entry plus an appended "/." will be "stat"'ed, likely
512 "stat"'ed, likely directories first. If that succeeds, it assumes 670 directories first, in order of their inode numbers. If that
513 that the entry is a directory or a symlink to directory (which will 671 succeeds, it assumes that the entry is a directory or a symlink to
514 be checked seperately). This is often faster than stat'ing the entry 672 directory (which will be checked seperately). This is often faster
515 itself because filesystems might detect the type of the entry 673 than stat'ing the entry itself because filesystems might detect the
516 without reading the inode data (e.g. ext2fs filetype feature). 674 type of the entry without reading the inode data (e.g. ext2fs
675 filetype feature), even on systems that cannot return the filetype
676 information on readdir.
517 677
518 If the known number of directories (link count - 2) has been 678 If the known number of directories (link count - 2) has been
519 reached, the rest of the entries is assumed to be non-directories. 679 reached, the rest of the entries is assumed to be non-directories.
520 680
521 This only works with certainty on POSIX (= UNIX) filesystems, which 681 This only works with certainty on POSIX (= UNIX) filesystems, which
543 callback with the fdatasync result code. 703 callback with the fdatasync result code.
544 704
545 If this call isn't available because your OS lacks it or it couldn't 705 If this call isn't available because your OS lacks it or it couldn't
546 be detected, it will be emulated by calling "fsync" instead. 706 be detected, it will be emulated by calling "fsync" instead.
547 707
708 aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
709 Sync the data portion of the file specified by $offset and $length
710 to disk (but NOT the metadata), by calling the Linux-specific
711 sync_file_range call. If sync_file_range is not available or it
712 returns ENOSYS, then fdatasync or fsync is being substituted.
713
714 $flags can be a combination of
715 "IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE",
716 "IO::AIO::SYNC_FILE_RANGE_WRITE" and
717 "IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER": refer to the sync_file_range
718 manpage for details.
719
548 aio_pathsync $path, $callback->($status) 720 aio_pathsync $path, $callback->($status)
549 This request tries to open, fsync and close the given path. This is 721 This request tries to open, fsync and close the given path. This is
550 a composite request intended tosync directories after directory 722 a composite request intended to sync directories after directory
551 operations (E.g. rename). This might not work on all operating 723 operations (E.g. rename). This might not work on all operating
552 systems or have any specific effect, but usually it makes sure that 724 systems or have any specific effect, but usually it makes sure that
553 directory changes get written to disc. It works for anything that 725 directory changes get written to disc. It works for anything that
554 can be opened for read-only, not just directories. 726 can be opened for read-only, not just directories.
555 727
728 Future versions of this function might fall back to other methods
729 when "fsync" on the directory fails (such as calling "sync").
730
556 Passes 0 when everything went ok, and -1 on error. 731 Passes 0 when everything went ok, and -1 on error.
732
733 aio_msync $scalar, $offset = 0, $length = undef, flags = 0,
734 $callback->($status)
735 This is a rather advanced IO::AIO call, which only works on
736 mmap(2)ed scalars (see the "IO::AIO::mmap" function, although it
737 also works on data scalars managed by the Sys::Mmap or Mmap modules,
738 note that the scalar must only be modified in-place while an aio
739 operation is pending on it).
740
741 It calls the "msync" function of your OS, if available, with the
742 memory area starting at $offset in the string and ending $length
743 bytes later. If $length is negative, counts from the end, and if
744 $length is "undef", then it goes till the end of the string. The
745 flags can be a combination of "IO::AIO::MS_ASYNC",
746 "IO::AIO::MS_INVALIDATE" and "IO::AIO::MS_SYNC".
747
748 aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0,
749 $callback->($status)
750 This is a rather advanced IO::AIO call, which works best on
751 mmap(2)ed scalars.
752
753 It touches (reads or writes) all memory pages in the specified range
754 inside the scalar. All caveats and parameters are the same as for
755 "aio_msync", above, except for flags, which must be either 0 (which
756 reads all pages and ensures they are instantiated) or
757 "IO::AIO::MT_MODIFY", which modifies the memory page s(by reading
758 and writing an octet from it, which dirties the page).
759
760 aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
761 This is a rather advanced IO::AIO call, which works best on
762 mmap(2)ed scalars.
763
764 It reads in all the pages of the underlying storage into memory (if
765 any) and locks them, so they are not getting swapped/paged out or
766 removed.
767
768 If $length is undefined, then the scalar will be locked till the
769 end.
770
771 On systems that do not implement "mlock", this function returns -1
772 and sets errno to "ENOSYS".
773
774 Note that the corresponding "munlock" is synchronous and is
775 documented under "MISCELLANEOUS FUNCTIONS".
776
777 Example: open a file, mmap and mlock it - both will be undone when
778 $data gets destroyed.
779
780 open my $fh, "<", $path or die "$path: $!";
781 my $data;
782 IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh;
783 aio_mlock $data; # mlock in background
784
785 aio_mlockall $flags, $callback->($status)
786 Calls the "mlockall" function with the given $flags (a combination
787 of "IO::AIO::MCL_CURRENT" and "IO::AIO::MCL_FUTURE").
788
789 On systems that do not implement "mlockall", this function returns
790 -1 and sets errno to "ENOSYS".
791
792 Note that the corresponding "munlockall" is synchronous and is
793 documented under "MISCELLANEOUS FUNCTIONS".
794
795 Example: asynchronously lock all current and future pages into
796 memory.
797
798 aio_mlockall IO::AIO::MCL_FUTURE;
557 799
558 aio_group $callback->(...) 800 aio_group $callback->(...)
559 This is a very special aio request: Instead of doing something, it 801 This is a very special aio request: Instead of doing something, it
560 is a container for other aio requests, which is useful if you want 802 is a container for other aio requests, which is useful if you want
561 to bundle many requests into a single, composite, request with a 803 to bundle many requests into a single, composite, request with a
604 846
605 cancel $req 847 cancel $req
606 Cancels the request, if possible. Has the effect of skipping 848 Cancels the request, if possible. Has the effect of skipping
607 execution when entering the execute state and skipping calling the 849 execution when entering the execute state and skipping calling the
608 callback when entering the the result state, but will leave the 850 callback when entering the the result state, but will leave the
609 request otherwise untouched. That means that requests that currently 851 request otherwise untouched (with the exception of readdir). That
610 execute will not be stopped and resources held by the request will 852 means that requests that currently execute will not be stopped and
611 not be freed prematurely. 853 resources held by the request will not be freed prematurely.
612 854
613 cb $req $callback->(...) 855 cb $req $callback->(...)
614 Replace (or simply set) the callback registered to the request. 856 Replace (or simply set) the callback registered to the request.
615 857
616 IO::AIO::GRP CLASS 858 IO::AIO::GRP CLASS
659 Their lifetime, simplified, looks like this: when they are empty, they 901 Their lifetime, simplified, looks like this: when they are empty, they
660 will finish very quickly. If they contain only requests that are in the 902 will finish very quickly. If they contain only requests that are in the
661 "done" state, they will also finish. Otherwise they will continue to 903 "done" state, they will also finish. Otherwise they will continue to
662 exist. 904 exist.
663 905
664 That means after creating a group you have some time to add requests. 906 That means after creating a group you have some time to add requests
665 And in the callbacks of those requests, you can add further requests to 907 (precisely before the callback has been invoked, which is only done
666 the group. And only when all those requests have finished will the the 908 within the "poll_cb"). And in the callbacks of those requests, you can
667 group itself finish. 909 add further requests to the group. And only when all those requests have
910 finished will the the group itself finish.
668 911
669 add $grp ... 912 add $grp ...
670 $grp->add (...) 913 $grp->add (...)
671 Add one or more requests to the group. Any type of IO::AIO::REQ can 914 Add one or more requests to the group. Any type of IO::AIO::REQ can
672 be added, including other groups, as long as you do not create 915 be added, including other groups, as long as you do not create
676 919
677 $grp->cancel_subs 920 $grp->cancel_subs
678 Cancel all subrequests and clears any feeder, but not the group 921 Cancel all subrequests and clears any feeder, but not the group
679 request itself. Useful when you queued a lot of events but got a 922 request itself. Useful when you queued a lot of events but got a
680 result early. 923 result early.
924
925 The group request will finish normally (you cannot add requests to
926 the group).
681 927
682 $grp->result (...) 928 $grp->result (...)
683 Set the result value(s) that will be passed to the group callback 929 Set the result value(s) that will be passed to the group callback
684 when all subrequests have finished and set the groups errno to the 930 when all subrequests have finished and set the groups errno to the
685 current value of errno (just like calling "errno" without an error 931 current value of errno (just like calling "errno" without an error
715 does not impose any limits). 961 does not impose any limits).
716 962
717 If the feed does not queue more requests when called, it will be 963 If the feed does not queue more requests when called, it will be
718 automatically removed from the group. 964 automatically removed from the group.
719 965
720 If the feed limit is 0, it will be set to 2 automatically. 966 If the feed limit is 0 when this method is called, it will be set to
967 2 automatically.
721 968
722 Example: 969 Example:
723 970
724 # stat all files in @files, but only ever use four aio requests concurrently: 971 # stat all files in @files, but only ever use four aio requests concurrently:
725 972
736 Sets the feeder limit for the group: The feeder will be called 983 Sets the feeder limit for the group: The feeder will be called
737 whenever the group contains less than this many requests. 984 whenever the group contains less than this many requests.
738 985
739 Setting the limit to 0 will pause the feeding process. 986 Setting the limit to 0 will pause the feeding process.
740 987
988 The default value for the limit is 0, but note that setting a feeder
989 automatically bumps it up to 2.
990
741 SUPPORT FUNCTIONS 991 SUPPORT FUNCTIONS
742 EVENT PROCESSING AND EVENT LOOP INTEGRATION 992 EVENT PROCESSING AND EVENT LOOP INTEGRATION
743 $fileno = IO::AIO::poll_fileno 993 $fileno = IO::AIO::poll_fileno
744 Return the *request result pipe file descriptor*. This filehandle 994 Return the *request result pipe file descriptor*. This filehandle
745 must be polled for reading by some mechanism outside this module 995 must be polled for reading by some mechanism outside this module
746 (e.g. Event or select, see below or the SYNOPSIS). If the pipe 996 (e.g. EV, Glib, select and so on, see below or the SYNOPSIS). If the
747 becomes readable you have to call "poll_cb" to check the results. 997 pipe becomes readable you have to call "poll_cb" to check the
998 results.
748 999
749 See "poll_cb" for an example. 1000 See "poll_cb" for an example.
750 1001
751 IO::AIO::poll_cb 1002 IO::AIO::poll_cb
752 Process some outstanding events on the result pipe. You have to call 1003 Process some outstanding events on the result pipe. You have to call
753 this regularly. Returns the number of events processed. Returns 1004 this regularly. Returns 0 if all events could be processed, or -1 if
754 immediately when no events are outstanding. The amount of events 1005 it returned earlier for whatever reason. Returns immediately when no
1006 events are outstanding. The amount of events processed depends on
755 processed depends on the settings of "IO::AIO::max_poll_req" and 1007 the settings of "IO::AIO::max_poll_req" and
756 "IO::AIO::max_poll_time". 1008 "IO::AIO::max_poll_time".
757 1009
758 If not all requests were processed for whatever reason, the 1010 If not all requests were processed for whatever reason, the
759 filehandle will still be ready when "poll_cb" returns. 1011 filehandle will still be ready when "poll_cb" returns, so normally
1012 you don't have to do anything special to have it called later.
760 1013
761 Example: Install an Event watcher that automatically calls 1014 Example: Install an Event watcher that automatically calls
762 IO::AIO::poll_cb with high priority: 1015 IO::AIO::poll_cb with high priority (more examples can be found in
1016 the SYNOPSIS section, at the top of this document):
763 1017
764 Event->io (fd => IO::AIO::poll_fileno, 1018 Event->io (fd => IO::AIO::poll_fileno,
765 poll => 'r', async => 1, 1019 poll => 'r', async => 1,
766 cb => \&IO::AIO::poll_cb); 1020 cb => \&IO::AIO::poll_cb);
1021
1022 IO::AIO::poll_wait
1023 If there are any outstanding requests and none of them in the result
1024 phase, wait till the result filehandle becomes ready for reading
1025 (simply does a "select" on the filehandle. This is useful if you
1026 want to synchronously wait for some requests to finish).
1027
1028 See "nreqs" for an example.
1029
1030 IO::AIO::poll
1031 Waits until some requests have been handled.
1032
1033 Returns the number of requests processed, but is otherwise strictly
1034 equivalent to:
1035
1036 IO::AIO::poll_wait, IO::AIO::poll_cb
1037
1038 IO::AIO::flush
1039 Wait till all outstanding AIO requests have been handled.
1040
1041 Strictly equivalent to:
1042
1043 IO::AIO::poll_wait, IO::AIO::poll_cb
1044 while IO::AIO::nreqs;
767 1045
768 IO::AIO::max_poll_reqs $nreqs 1046 IO::AIO::max_poll_reqs $nreqs
769 IO::AIO::max_poll_time $seconds 1047 IO::AIO::max_poll_time $seconds
770 These set the maximum number of requests (default 0, meaning 1048 These set the maximum number of requests (default 0, meaning
771 infinity) that are being processed by "IO::AIO::poll_cb" in one 1049 infinity) that are being processed by "IO::AIO::poll_cb" in one
795 # use a low priority so other tasks have priority 1073 # use a low priority so other tasks have priority
796 Event->io (fd => IO::AIO::poll_fileno, 1074 Event->io (fd => IO::AIO::poll_fileno,
797 poll => 'r', nice => 1, 1075 poll => 'r', nice => 1,
798 cb => &IO::AIO::poll_cb); 1076 cb => &IO::AIO::poll_cb);
799 1077
800 IO::AIO::poll_wait
801 If there are any outstanding requests and none of them in the result
802 phase, wait till the result filehandle becomes ready for reading
803 (simply does a "select" on the filehandle. This is useful if you
804 want to synchronously wait for some requests to finish).
805
806 See "nreqs" for an example.
807
808 IO::AIO::poll
809 Waits until some requests have been handled.
810
811 Returns the number of requests processed, but is otherwise strictly
812 equivalent to:
813
814 IO::AIO::poll_wait, IO::AIO::poll_cb
815
816 IO::AIO::flush
817 Wait till all outstanding AIO requests have been handled.
818
819 Strictly equivalent to:
820
821 IO::AIO::poll_wait, IO::AIO::poll_cb
822 while IO::AIO::nreqs;
823
824 CONTROLLING THE NUMBER OF THREADS 1078 CONTROLLING THE NUMBER OF THREADS
825 IO::AIO::min_parallel $nthreads 1079 IO::AIO::min_parallel $nthreads
826 Set the minimum number of AIO threads to $nthreads. The current 1080 Set the minimum number of AIO threads to $nthreads. The current
827 default is 8, which means eight asynchronous operations can execute 1081 default is 8, which means eight asynchronous operations can execute
828 concurrently at any one time (the number of outstanding requests, 1082 concurrently at any one time (the number of outstanding requests,
870 1124
871 The default is probably ok in most situations, especially if thread 1125 The default is probably ok in most situations, especially if thread
872 creation is fast. If thread creation is very slow on your system you 1126 creation is fast. If thread creation is very slow on your system you
873 might want to use larger values. 1127 might want to use larger values.
874 1128
875 $oldmaxreqs = IO::AIO::max_outstanding $maxreqs 1129 IO::AIO::max_outstanding $maxreqs
876 This is a very bad function to use in interactive programs because 1130 This is a very bad function to use in interactive programs because
877 it blocks, and a bad way to reduce concurrency because it is 1131 it blocks, and a bad way to reduce concurrency because it is
878 inexact: Better use an "aio_group" together with a feed callback. 1132 inexact: Better use an "aio_group" together with a feed callback.
879 1133
880 Sets the maximum number of outstanding requests to $nreqs. If you do 1134 Sets the maximum number of outstanding requests to $nreqs. If you do
884 1138
885 The default value is very large, so there is no practical limit on 1139 The default value is very large, so there is no practical limit on
886 the number of outstanding requests. 1140 the number of outstanding requests.
887 1141
888 You can still queue as many requests as you want. Therefore, 1142 You can still queue as many requests as you want. Therefore,
889 "max_oustsanding" is mainly useful in simple scripts (with low 1143 "max_outstanding" is mainly useful in simple scripts (with low
890 values) or as a stop gap to shield against fatal memory overflow 1144 values) or as a stop gap to shield against fatal memory overflow
891 (with large values). 1145 (with large values).
892 1146
893 STATISTICAL INFORMATION 1147 STATISTICAL INFORMATION
894 IO::AIO::nreqs 1148 IO::AIO::nreqs
906 executed). 1160 executed).
907 1161
908 IO::AIO::npending 1162 IO::AIO::npending
909 Returns the number of requests currently in the pending state 1163 Returns the number of requests currently in the pending state
910 (executed, but not yet processed by poll_cb). 1164 (executed, but not yet processed by poll_cb).
1165
1166 MISCELLANEOUS FUNCTIONS
1167 IO::AIO implements some functions that might be useful, but are not
1168 asynchronous.
1169
1170 IO::AIO::sendfile $ofh, $ifh, $offset, $count
1171 Calls the "eio_sendfile_sync" function, which is like
1172 "aio_sendfile", but is blocking (this makes most sense if you know
1173 the input data is likely cached already and the output filehandle is
1174 set to non-blocking operations).
1175
1176 Returns the number of bytes copied, or -1 on error.
1177
1178 IO::AIO::fadvise $fh, $offset, $len, $advice
1179 Simply calls the "posix_fadvise" function (see its manpage for
1180 details). The following advice constants are avaiable:
1181 "IO::AIO::FADV_NORMAL", "IO::AIO::FADV_SEQUENTIAL",
1182 "IO::AIO::FADV_RANDOM", "IO::AIO::FADV_NOREUSE",
1183 "IO::AIO::FADV_WILLNEED", "IO::AIO::FADV_DONTNEED".
1184
1185 On systems that do not implement "posix_fadvise", this function
1186 returns ENOSYS, otherwise the return value of "posix_fadvise".
1187
1188 IO::AIO::madvise $scalar, $offset, $len, $advice
1189 Simply calls the "posix_madvise" function (see its manpage for
1190 details). The following advice constants are avaiable:
1191 "IO::AIO::MADV_NORMAL", "IO::AIO::MADV_SEQUENTIAL",
1192 "IO::AIO::MADV_RANDOM", "IO::AIO::MADV_WILLNEED",
1193 "IO::AIO::MADV_DONTNEED".
1194
1195 On systems that do not implement "posix_madvise", this function
1196 returns ENOSYS, otherwise the return value of "posix_madvise".
1197
1198 IO::AIO::mprotect $scalar, $offset, $len, $protect
1199 Simply calls the "mprotect" function on the preferably AIO::mmap'ed
1200 $scalar (see its manpage for details). The following protect
1201 constants are avaiable: "IO::AIO::PROT_NONE", "IO::AIO::PROT_READ",
1202 "IO::AIO::PROT_WRITE", "IO::AIO::PROT_EXEC".
1203
1204 On systems that do not implement "mprotect", this function returns
1205 ENOSYS, otherwise the return value of "mprotect".
1206
1207 IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset]
1208 Memory-maps a file (or anonymous memory range) and attaches it to
1209 the given $scalar, which will act like a string scalar.
1210
1211 The only operations allowed on the scalar are "substr"/"vec" that
1212 don't change the string length, and most read-only operations such
1213 as copying it or searching it with regexes and so on.
1214
1215 Anything else is unsafe and will, at best, result in memory leaks.
1216
1217 The memory map associated with the $scalar is automatically removed
1218 when the $scalar is destroyed, or when the "IO::AIO::mmap" or
1219 "IO::AIO::munmap" functions are called.
1220
1221 This calls the "mmap"(2) function internally. See your system's
1222 manual page for details on the $length, $prot and $flags parameters.
1223
1224 The $length must be larger than zero and smaller than the actual
1225 filesize.
1226
1227 $prot is a combination of "IO::AIO::PROT_NONE",
1228 "IO::AIO::PROT_EXEC", "IO::AIO::PROT_READ" and/or
1229 "IO::AIO::PROT_WRITE",
1230
1231 $flags can be a combination of "IO::AIO::MAP_SHARED" or
1232 "IO::AIO::MAP_PRIVATE", or a number of system-specific flags (when
1233 not available, the are defined as 0): "IO::AIO::MAP_ANONYMOUS"
1234 (which is set to "MAP_ANON" if your system only provides this
1235 constant), "IO::AIO::MAP_HUGETLB", "IO::AIO::MAP_LOCKED",
1236 "IO::AIO::MAP_NORESERVE", "IO::AIO::MAP_POPULATE" or
1237 "IO::AIO::MAP_NONBLOCK"
1238
1239 If $fh is "undef", then a file descriptor of -1 is passed.
1240
1241 $offset is the offset from the start of the file - it generally must
1242 be a multiple of "IO::AIO::PAGESIZE" and defaults to 0.
1243
1244 Example:
1245
1246 use Digest::MD5;
1247 use IO::AIO;
1248
1249 open my $fh, "<verybigfile"
1250 or die "$!";
1251
1252 IO::AIO::mmap my $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh
1253 or die "verybigfile: $!";
1254
1255 my $fast_md5 = md5 $data;
1256
1257 IO::AIO::munmap $scalar
1258 Removes a previous mmap and undefines the $scalar.
1259
1260 IO::AIO::munlock $scalar, $offset = 0, $length = undef
1261 Calls the "munlock" function, undoing the effects of a previous
1262 "aio_mlock" call (see its description for details).
1263
1264 IO::AIO::munlockall
1265 Calls the "munlockall" function.
1266
1267 On systems that do not implement "munlockall", this function returns
1268 ENOSYS, otherwise the return value of "munlockall".
1269
1270EVENT LOOP INTEGRATION
1271 It is recommended to use AnyEvent::AIO to integrate IO::AIO
1272 automatically into many event loops:
1273
1274 # AnyEvent integration (EV, Event, Glib, Tk, POE, urxvt, pureperl...)
1275 use AnyEvent::AIO;
1276
1277 You can also integrate IO::AIO manually into many event loops, here are
1278 some examples of how to do this:
1279
1280 # EV integration
1281 my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb;
1282
1283 # Event integration
1284 Event->io (fd => IO::AIO::poll_fileno,
1285 poll => 'r',
1286 cb => \&IO::AIO::poll_cb);
1287
1288 # Glib/Gtk2 integration
1289 add_watch Glib::IO IO::AIO::poll_fileno,
1290 in => sub { IO::AIO::poll_cb; 1 };
1291
1292 # Tk integration
1293 Tk::Event::IO->fileevent (IO::AIO::poll_fileno, "",
1294 readable => \&IO::AIO::poll_cb);
1295
1296 # Danga::Socket integration
1297 Danga::Socket->AddOtherFds (IO::AIO::poll_fileno =>
1298 \&IO::AIO::poll_cb);
911 1299
912 FORK BEHAVIOUR 1300 FORK BEHAVIOUR
913 This module should do "the right thing" when the process using it forks: 1301 This module should do "the right thing" when the process using it forks:
914 1302
915 Before the fork, IO::AIO enters a quiescent state where no requests can 1303 Before the fork, IO::AIO enters a quiescent state where no requests can
944 1332
945KNOWN BUGS 1333KNOWN BUGS
946 Known bugs will be fixed in the next release. 1334 Known bugs will be fixed in the next release.
947 1335
948SEE ALSO 1336SEE ALSO
949 Coro::AIO. 1337 AnyEvent::AIO for easy integration into event loops, Coro::AIO for a
1338 more natural syntax.
950 1339
951AUTHOR 1340AUTHOR
952 Marc Lehmann <schmorp@schmorp.de> 1341 Marc Lehmann <schmorp@schmorp.de>
953 http://home.schmorp.de/ 1342 http://home.schmorp.de/
954 1343

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