| 1 | =head1 NAME |
1 | =head1 NAME |
| 2 | |
2 | |
| 3 | IO::AIO - Asynchronous Input/Output |
3 | IO::AIO - Asynchronous/Advanced Input/Output |
| 4 | |
4 | |
| 5 | =head1 SYNOPSIS |
5 | =head1 SYNOPSIS |
| 6 | |
6 | |
| 7 | use IO::AIO; |
7 | use IO::AIO; |
| 8 | |
8 | |
| … | |
… | |
| 58 | not well-supported or restricted (GNU/Linux doesn't allow them on normal |
58 | not well-supported or restricted (GNU/Linux doesn't allow them on normal |
| 59 | files currently, for example), and they would only support aio_read and |
59 | files currently, for example), and they would only support aio_read and |
| 60 | aio_write, so the remaining functionality would have to be implemented |
60 | aio_write, so the remaining functionality would have to be implemented |
| 61 | using threads anyway. |
61 | using threads anyway. |
| 62 | |
62 | |
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63 | In addition to asynchronous I/O, this module also exports some rather |
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64 | arcane interfaces, such as C<madvise> or linux's C<splice> system call, |
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65 | which is why the C<A> in C<AIO> can also mean I<advanced>. |
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66 | |
| 63 | Although the module will work in the presence of other (Perl-) threads, |
67 | Although the module will work in the presence of other (Perl-) threads, |
| 64 | it is currently not reentrant in any way, so use appropriate locking |
68 | it is currently not reentrant in any way, so use appropriate locking |
| 65 | yourself, always call C<poll_cb> from within the same thread, or never |
69 | yourself, always call C<poll_cb> from within the same thread, or never |
| 66 | call C<poll_cb> (or other C<aio_> functions) recursively. |
70 | call C<poll_cb> (or other C<aio_> functions) recursively. |
| 67 | |
71 | |
| 68 | =head2 EXAMPLE |
72 | =head2 EXAMPLE |
| 69 | |
73 | |
| 70 | This is a simple example that uses the EV module and loads |
74 | This is a simple example that uses the EV module and loads |
| 71 | F</etc/passwd> asynchronously: |
75 | F</etc/passwd> asynchronously: |
| 72 | |
76 | |
| 73 | use Fcntl; |
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|
| 74 | use EV; |
77 | use EV; |
| 75 | use IO::AIO; |
78 | use IO::AIO; |
| 76 | |
79 | |
| 77 | # register the IO::AIO callback with EV |
80 | # register the IO::AIO callback with EV |
| 78 | my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb; |
81 | my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb; |
| … | |
… | |
| 95 | |
98 | |
| 96 | # file contents now in $contents |
99 | # file contents now in $contents |
| 97 | print $contents; |
100 | print $contents; |
| 98 | |
101 | |
| 99 | # exit event loop and program |
102 | # exit event loop and program |
| 100 | EV::unloop; |
103 | EV::break; |
| 101 | }; |
104 | }; |
| 102 | }; |
105 | }; |
| 103 | |
106 | |
| 104 | # possibly queue up other requests, or open GUI windows, |
107 | # possibly queue up other requests, or open GUI windows, |
| 105 | # check for sockets etc. etc. |
108 | # check for sockets etc. etc. |
| 106 | |
109 | |
| 107 | # process events as long as there are some: |
110 | # process events as long as there are some: |
| 108 | EV::loop; |
111 | EV::run; |
| 109 | |
112 | |
| 110 | =head1 REQUEST ANATOMY AND LIFETIME |
113 | =head1 REQUEST ANATOMY AND LIFETIME |
| 111 | |
114 | |
| 112 | Every C<aio_*> function creates a request. which is a C data structure not |
115 | Every C<aio_*> function creates a request. which is a C data structure not |
| 113 | directly visible to Perl. |
116 | directly visible to Perl. |
| … | |
… | |
| 168 | use common::sense; |
171 | use common::sense; |
| 169 | |
172 | |
| 170 | use base 'Exporter'; |
173 | use base 'Exporter'; |
| 171 | |
174 | |
| 172 | BEGIN { |
175 | BEGIN { |
| 173 | our $VERSION = '4.15'; |
176 | our $VERSION = 4.4; |
| 174 | |
177 | |
| 175 | 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 |
| 176 | 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 |
| 177 | aio_scandir aio_symlink aio_readlink aio_realpath aio_sync |
180 | aio_scandir aio_symlink aio_readlink aio_realpath aio_fcntl aio_ioctl |
| 178 | aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range aio_fallocate |
181 | aio_sync aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range |
| 179 | aio_pathsync aio_readahead aio_fiemap |
182 | aio_pathsync aio_readahead aio_fiemap aio_allocate |
| 180 | aio_rename aio_link aio_move aio_copy aio_group |
183 | aio_rename aio_rename2 aio_link aio_move aio_copy aio_group |
| 181 | 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 |
| 182 | aio_chmod aio_utime aio_truncate |
185 | aio_chmod aio_utime aio_truncate |
| 183 | aio_msync aio_mtouch aio_mlock aio_mlockall |
186 | aio_msync aio_mtouch aio_mlock aio_mlockall |
| 184 | aio_statvfs |
187 | aio_statvfs |
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188 | aio_slurp |
| 185 | aio_wd); |
189 | aio_wd); |
| 186 | |
190 | |
| 187 | our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice)); |
191 | our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice)); |
| 188 | our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush |
192 | our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush |
| 189 | min_parallel max_parallel max_idle idle_timeout |
193 | min_parallel max_parallel max_idle idle_timeout |
| … | |
… | |
| 228 | aio_unlink $pathname, $callback->($status) |
232 | aio_unlink $pathname, $callback->($status) |
| 229 | aio_mknod $pathname, $mode, $dev, $callback->($status) |
233 | aio_mknod $pathname, $mode, $dev, $callback->($status) |
| 230 | aio_link $srcpath, $dstpath, $callback->($status) |
234 | aio_link $srcpath, $dstpath, $callback->($status) |
| 231 | aio_symlink $srcpath, $dstpath, $callback->($status) |
235 | aio_symlink $srcpath, $dstpath, $callback->($status) |
| 232 | aio_readlink $pathname, $callback->($link) |
236 | aio_readlink $pathname, $callback->($link) |
| 233 | aio_realpath $pathname, $callback->($link) |
237 | aio_realpath $pathname, $callback->($path) |
| 234 | aio_rename $srcpath, $dstpath, $callback->($status) |
238 | aio_rename $srcpath, $dstpath, $callback->($status) |
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239 | aio_rename2 $srcpath, $dstpath, $flags, $callback->($status) |
| 235 | aio_mkdir $pathname, $mode, $callback->($status) |
240 | aio_mkdir $pathname, $mode, $callback->($status) |
| 236 | aio_rmdir $pathname, $callback->($status) |
241 | aio_rmdir $pathname, $callback->($status) |
| 237 | aio_readdir $pathname, $callback->($entries) |
242 | aio_readdir $pathname, $callback->($entries) |
| 238 | aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
243 | aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
| 239 | IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST |
244 | IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST |
| … | |
… | |
| 241 | aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs) |
246 | aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs) |
| 242 | aio_load $pathname, $data, $callback->($status) |
247 | aio_load $pathname, $data, $callback->($status) |
| 243 | aio_copy $srcpath, $dstpath, $callback->($status) |
248 | aio_copy $srcpath, $dstpath, $callback->($status) |
| 244 | aio_move $srcpath, $dstpath, $callback->($status) |
249 | aio_move $srcpath, $dstpath, $callback->($status) |
| 245 | aio_rmtree $pathname, $callback->($status) |
250 | aio_rmtree $pathname, $callback->($status) |
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|
251 | aio_fcntl $fh, $cmd, $arg, $callback->($status) |
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252 | aio_ioctl $fh, $request, $buf, $callback->($status) |
| 246 | aio_sync $callback->($status) |
253 | aio_sync $callback->($status) |
| 247 | aio_syncfs $fh, $callback->($status) |
254 | aio_syncfs $fh, $callback->($status) |
| 248 | aio_fsync $fh, $callback->($status) |
255 | aio_fsync $fh, $callback->($status) |
| 249 | aio_fdatasync $fh, $callback->($status) |
256 | aio_fdatasync $fh, $callback->($status) |
| 250 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
257 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
| 251 | aio_pathsync $pathname, $callback->($status) |
258 | aio_pathsync $pathname, $callback->($status) |
| 252 | aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
259 | aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status) |
| 253 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
260 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
| 254 | aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
261 | aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
| 255 | aio_mlockall $flags, $callback->($status) |
262 | aio_mlockall $flags, $callback->($status) |
| 256 | aio_group $callback->(...) |
263 | aio_group $callback->(...) |
| 257 | aio_nop $callback->() |
264 | aio_nop $callback->() |
| … | |
… | |
| 271 | IO::AIO::idle_timeout $seconds |
278 | IO::AIO::idle_timeout $seconds |
| 272 | IO::AIO::max_outstanding $maxreqs |
279 | IO::AIO::max_outstanding $maxreqs |
| 273 | IO::AIO::nreqs |
280 | IO::AIO::nreqs |
| 274 | IO::AIO::nready |
281 | IO::AIO::nready |
| 275 | IO::AIO::npending |
282 | IO::AIO::npending |
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|
283 | $nfd = IO::AIO::get_fdlimit [EXPERIMENTAL] |
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284 | IO::AIO::min_fdlimit $nfd [EXPERIMENTAL] |
| 276 | |
285 | |
| 277 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
286 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
| 278 | IO::AIO::fadvise $fh, $offset, $len, $advice |
287 | IO::AIO::fadvise $fh, $offset, $len, $advice |
| 279 | IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]] |
288 | IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]] |
| 280 | IO::AIO::munmap $scalar |
289 | IO::AIO::munmap $scalar |
| … | |
… | |
| 362 | |
371 | |
| 363 | |
372 | |
| 364 | =item aio_open $pathname, $flags, $mode, $callback->($fh) |
373 | =item aio_open $pathname, $flags, $mode, $callback->($fh) |
| 365 | |
374 | |
| 366 | Asynchronously open or create a file and call the callback with a newly |
375 | Asynchronously open or create a file and call the callback with a newly |
| 367 | created filehandle for the file. |
376 | created filehandle for the file (or C<undef> in case of an error). |
| 368 | |
377 | |
| 369 | The pathname passed to C<aio_open> must be absolute. See API NOTES, above, |
378 | The pathname passed to C<aio_open> must be absolute. See API NOTES, above, |
| 370 | for an explanation. |
379 | for an explanation. |
| 371 | |
380 | |
| 372 | The C<$flags> argument is a bitmask. See the C<Fcntl> module for a |
381 | The C<$flags> argument is a bitmask. See the C<Fcntl> module for a |
| … | |
… | |
| 395 | following POSIX and non-POSIX constants are available (missing ones on |
404 | following POSIX and non-POSIX constants are available (missing ones on |
| 396 | your system are, as usual, C<0>): |
405 | your system are, as usual, C<0>): |
| 397 | |
406 | |
| 398 | C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>, |
407 | C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>, |
| 399 | C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>, |
408 | C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>, |
| 400 | C<O_RSYNC>, C<O_SYNC> and C<O_TTY_INIT>. |
409 | C<O_RSYNC>, C<O_SYNC>, C<O_PATH>, C<O_TMPFILE>, and C<O_TTY_INIT>. |
| 401 | |
410 | |
| 402 | |
411 | |
| 403 | =item aio_close $fh, $callback->($status) |
412 | =item aio_close $fh, $callback->($status) |
| 404 | |
413 | |
| 405 | Asynchronously close a file and call the callback with the result |
414 | Asynchronously close a file and call the callback with the result |
| … | |
… | |
| 440 | =item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
449 | =item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
| 441 | |
450 | |
| 442 | =item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
451 | =item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
| 443 | |
452 | |
| 444 | Reads or writes C<$length> bytes from or to the specified C<$fh> and |
453 | Reads or writes C<$length> bytes from or to the specified C<$fh> and |
| 445 | C<$offset> into the scalar given by C<$data> and offset C<$dataoffset> |
454 | C<$offset> into the scalar given by C<$data> and offset C<$dataoffset> and |
| 446 | and calls the callback without the actual number of bytes read (or -1 on |
455 | calls the callback with the actual number of bytes transferred (or -1 on |
| 447 | error, just like the syscall). |
456 | error, just like the syscall). |
| 448 | |
457 | |
| 449 | C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to |
458 | C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to |
| 450 | offset plus the actual number of bytes read. |
459 | offset plus the actual number of bytes read. |
| 451 | |
460 | |
| … | |
… | |
| 509 | As native sendfile syscalls (as practically any non-POSIX interface hacked |
518 | As native sendfile syscalls (as practically any non-POSIX interface hacked |
| 510 | together in a hurry to improve benchmark numbers) tend to be rather buggy |
519 | together in a hurry to improve benchmark numbers) tend to be rather buggy |
| 511 | on many systems, this implementation tries to work around some known bugs |
520 | on many systems, this implementation tries to work around some known bugs |
| 512 | in Linux and FreeBSD kernels (probably others, too), but that might fail, |
521 | in Linux and FreeBSD kernels (probably others, too), but that might fail, |
| 513 | so you really really should check the return value of C<aio_sendfile> - |
522 | so you really really should check the return value of C<aio_sendfile> - |
| 514 | fewre bytes than expected might have been transferred. |
523 | fewer bytes than expected might have been transferred. |
| 515 | |
524 | |
| 516 | |
525 | |
| 517 | =item aio_readahead $fh,$offset,$length, $callback->($retval) |
526 | =item aio_readahead $fh,$offset,$length, $callback->($retval) |
| 518 | |
527 | |
| 519 | C<aio_readahead> populates the page cache with data from a file so that |
528 | C<aio_readahead> populates the page cache with data from a file so that |
| … | |
… | |
| 523 | whole pages, so that offset is effectively rounded down to a page boundary |
532 | whole pages, so that offset is effectively rounded down to a page boundary |
| 524 | and bytes are read up to the next page boundary greater than or equal to |
533 | and bytes are read up to the next page boundary greater than or equal to |
| 525 | (off-set+length). C<aio_readahead> does not read beyond the end of the |
534 | (off-set+length). C<aio_readahead> does not read beyond the end of the |
| 526 | file. The current file offset of the file is left unchanged. |
535 | file. The current file offset of the file is left unchanged. |
| 527 | |
536 | |
| 528 | If that syscall doesn't exist (likely if your OS isn't Linux) it will be |
537 | If that syscall doesn't exist (likely if your kernel isn't Linux) it will |
| 529 | emulated by simply reading the data, which would have a similar effect. |
538 | be emulated by simply reading the data, which would have a similar effect. |
| 530 | |
539 | |
| 531 | |
540 | |
| 532 | =item aio_stat $fh_or_path, $callback->($status) |
541 | =item aio_stat $fh_or_path, $callback->($status) |
| 533 | |
542 | |
| 534 | =item aio_lstat $fh, $callback->($status) |
543 | =item aio_lstat $fh, $callback->($status) |
| … | |
… | |
| 603 | namemax => 255, |
612 | namemax => 255, |
| 604 | frsize => 1024, |
613 | frsize => 1024, |
| 605 | fsid => 1810 |
614 | fsid => 1810 |
| 606 | } |
615 | } |
| 607 | |
616 | |
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617 | Here is a (likely partial - send me updates!) list of fsid values used by |
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618 | Linux - it is safe to hardcode these when C<$^O> is C<linux>: |
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619 | |
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620 | 0x0000adf5 adfs |
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621 | 0x0000adff affs |
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622 | 0x5346414f afs |
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623 | 0x09041934 anon-inode filesystem |
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624 | 0x00000187 autofs |
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625 | 0x42465331 befs |
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626 | 0x1badface bfs |
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627 | 0x42494e4d binfmt_misc |
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628 | 0x9123683e btrfs |
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629 | 0x0027e0eb cgroupfs |
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630 | 0xff534d42 cifs |
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631 | 0x73757245 coda |
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632 | 0x012ff7b7 coh |
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633 | 0x28cd3d45 cramfs |
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634 | 0x453dcd28 cramfs-wend (wrong endianness) |
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635 | 0x64626720 debugfs |
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636 | 0x00001373 devfs |
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637 | 0x00001cd1 devpts |
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638 | 0x0000f15f ecryptfs |
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639 | 0x00414a53 efs |
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640 | 0x0000137d ext |
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641 | 0x0000ef53 ext2/ext3/ext4 |
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642 | 0x0000ef51 ext2 |
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643 | 0xf2f52010 f2fs |
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644 | 0x00004006 fat |
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645 | 0x65735546 fuseblk |
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646 | 0x65735543 fusectl |
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647 | 0x0bad1dea futexfs |
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648 | 0x01161970 gfs2 |
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649 | 0x47504653 gpfs |
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650 | 0x00004244 hfs |
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651 | 0xf995e849 hpfs |
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652 | 0x00c0ffee hostfs |
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653 | 0x958458f6 hugetlbfs |
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654 | 0x2bad1dea inotifyfs |
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655 | 0x00009660 isofs |
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656 | 0x000072b6 jffs2 |
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657 | 0x3153464a jfs |
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658 | 0x6b414653 k-afs |
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659 | 0x0bd00bd0 lustre |
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660 | 0x0000137f minix |
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661 | 0x0000138f minix 30 char names |
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662 | 0x00002468 minix v2 |
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663 | 0x00002478 minix v2 30 char names |
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664 | 0x00004d5a minix v3 |
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665 | 0x19800202 mqueue |
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666 | 0x00004d44 msdos |
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667 | 0x0000564c novell |
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668 | 0x00006969 nfs |
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669 | 0x6e667364 nfsd |
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670 | 0x00003434 nilfs |
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671 | 0x5346544e ntfs |
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672 | 0x00009fa1 openprom |
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673 | 0x7461636F ocfs2 |
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674 | 0x00009fa0 proc |
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675 | 0x6165676c pstorefs |
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676 | 0x0000002f qnx4 |
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677 | 0x68191122 qnx6 |
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678 | 0x858458f6 ramfs |
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679 | 0x52654973 reiserfs |
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680 | 0x00007275 romfs |
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681 | 0x67596969 rpc_pipefs |
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682 | 0x73636673 securityfs |
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683 | 0xf97cff8c selinux |
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684 | 0x0000517b smb |
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685 | 0x534f434b sockfs |
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686 | 0x73717368 squashfs |
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687 | 0x62656572 sysfs |
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688 | 0x012ff7b6 sysv2 |
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689 | 0x012ff7b5 sysv4 |
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690 | 0x01021994 tmpfs |
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691 | 0x15013346 udf |
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692 | 0x00011954 ufs |
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693 | 0x54190100 ufs byteswapped |
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694 | 0x00009fa2 usbdevfs |
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695 | 0x01021997 v9fs |
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696 | 0xa501fcf5 vxfs |
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697 | 0xabba1974 xenfs |
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698 | 0x012ff7b4 xenix |
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699 | 0x58465342 xfs |
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700 | 0x012fd16d xia |
| 608 | |
701 | |
| 609 | =item aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
702 | =item aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
| 610 | |
703 | |
| 611 | Works like perl's C<utime> function (including the special case of $atime |
704 | Works like perl's C<utime> function (including the special case of $atime |
| 612 | and $mtime being undef). Fractional times are supported if the underlying |
705 | and $mtime being undef). Fractional times are supported if the underlying |
| … | |
… | |
| 642 | Works like truncate(2) or ftruncate(2). |
735 | Works like truncate(2) or ftruncate(2). |
| 643 | |
736 | |
| 644 | |
737 | |
| 645 | =item aio_allocate $fh, $mode, $offset, $len, $callback->($status) |
738 | =item aio_allocate $fh, $mode, $offset, $len, $callback->($status) |
| 646 | |
739 | |
| 647 | Allocates or freed disk space according to the C<$mode> argument. See the |
740 | Allocates or frees disk space according to the C<$mode> argument. See the |
| 648 | linux C<fallocate> docuemntation for details. |
741 | linux C<fallocate> documentation for details. |
| 649 | |
742 | |
| 650 | C<$mode> can currently be C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> |
743 | C<$mode> is usually C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> to allocate |
| 651 | to allocate space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE | |
744 | space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE | IO::AIO::FALLOC_FL_KEEP_SIZE>, |
| 652 | IO::AIO::FALLOC_FL_KEEP_SIZE>, to deallocate a file range. |
745 | to deallocate a file range. |
|
|
746 | |
|
|
747 | IO::AIO also supports C<FALLOC_FL_COLLAPSE_RANGE>, to remove a range |
|
|
748 | (without leaving a hole), C<FALLOC_FL_ZERO_RANGE>, to zero a range, |
|
|
749 | C<FALLOC_FL_INSERT_RANGE> to insert a range and C<FALLOC_FL_UNSHARE_RANGE> |
|
|
750 | to unshare shared blocks (see your L<fallocate(2)> manpage). |
| 653 | |
751 | |
| 654 | The file system block size used by C<fallocate> is presumably the |
752 | The file system block size used by C<fallocate> is presumably the |
| 655 | C<f_bsize> returned by C<statvfs>. |
753 | C<f_bsize> returned by C<statvfs>, but different filesystems and filetypes |
|
|
754 | can dictate other limitations. |
| 656 | |
755 | |
| 657 | If C<fallocate> isn't available or cannot be emulated (currently no |
756 | If C<fallocate> isn't available or cannot be emulated (currently no |
| 658 | emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>. |
757 | emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>. |
| 659 | |
758 | |
| 660 | |
759 | |
| … | |
… | |
| 702 | |
801 | |
| 703 | |
802 | |
| 704 | =item aio_realpath $pathname, $callback->($path) |
803 | =item aio_realpath $pathname, $callback->($path) |
| 705 | |
804 | |
| 706 | Asynchronously make the path absolute and resolve any symlinks in |
805 | Asynchronously make the path absolute and resolve any symlinks in |
| 707 | C<$path>. The resulting path only consists of directories (Same as |
806 | C<$path>. The resulting path only consists of directories (same as |
| 708 | L<Cwd::realpath>). |
807 | L<Cwd::realpath>). |
| 709 | |
808 | |
| 710 | This request can be used to get the absolute path of the current working |
809 | This request can be used to get the absolute path of the current working |
| 711 | directory by passing it a path of F<.> (a single dot). |
810 | directory by passing it a path of F<.> (a single dot). |
| 712 | |
811 | |
| 713 | |
812 | |
| 714 | =item aio_rename $srcpath, $dstpath, $callback->($status) |
813 | =item aio_rename $srcpath, $dstpath, $callback->($status) |
| 715 | |
814 | |
| 716 | Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as |
815 | Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as |
| 717 | rename(2) and call the callback with the result code. |
816 | rename(2) and call the callback with the result code. |
|
|
817 | |
|
|
818 | On systems that support the AIO::WD working directory abstraction |
|
|
819 | natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead |
|
|
820 | of failing, C<rename> is called on the absolute path of C<$wd>. |
|
|
821 | |
|
|
822 | |
|
|
823 | =item aio_rename2 $srcpath, $dstpath, $flags, $callback->($status) |
|
|
824 | |
|
|
825 | Basically a version of C<aio_rename> with an additional C<$flags> |
|
|
826 | argument. Calling this with C<$flags=0> is the same as calling |
|
|
827 | C<aio_rename>. |
|
|
828 | |
|
|
829 | Non-zero flags are currently only supported on GNU/Linux systems that |
|
|
830 | support renameat2. Other systems fail with C<ENOSYS> in this case. |
|
|
831 | |
|
|
832 | The following constants are available (missing ones are, as usual C<0>), |
|
|
833 | see renameat2(2) for details: |
|
|
834 | |
|
|
835 | C<IO::AIO::RENAME_NOREPLACE>, C<IO::AIO::RENAME_EXCHANGE> |
|
|
836 | and C<IO::AIO::RENAME_WHITEOUT>. |
| 718 | |
837 | |
| 719 | |
838 | |
| 720 | =item aio_mkdir $pathname, $mode, $callback->($status) |
839 | =item aio_mkdir $pathname, $mode, $callback->($status) |
| 721 | |
840 | |
| 722 | Asynchronously mkdir (create) a directory and call the callback with |
841 | Asynchronously mkdir (create) a directory and call the callback with |
| … | |
… | |
| 726 | |
845 | |
| 727 | =item aio_rmdir $pathname, $callback->($status) |
846 | =item aio_rmdir $pathname, $callback->($status) |
| 728 | |
847 | |
| 729 | Asynchronously rmdir (delete) a directory and call the callback with the |
848 | Asynchronously rmdir (delete) a directory and call the callback with the |
| 730 | result code. |
849 | result code. |
|
|
850 | |
|
|
851 | On systems that support the AIO::WD working directory abstraction |
|
|
852 | natively, the case C<[$wd, "."]> is specialcased - instead of failing, |
|
|
853 | C<rmdir> is called on the absolute path of C<$wd>. |
| 731 | |
854 | |
| 732 | |
855 | |
| 733 | =item aio_readdir $pathname, $callback->($entries) |
856 | =item aio_readdir $pathname, $callback->($entries) |
| 734 | |
857 | |
| 735 | Unlike the POSIX call of the same name, C<aio_readdir> reads an entire |
858 | Unlike the POSIX call of the same name, C<aio_readdir> reads an entire |
| … | |
… | |
| 804 | C<$type>'s are known, which can be used to speed up some algorithms. |
927 | C<$type>'s are known, which can be used to speed up some algorithms. |
| 805 | |
928 | |
| 806 | =back |
929 | =back |
| 807 | |
930 | |
| 808 | |
931 | |
|
|
932 | =item aio_slurp $pathname, $offset, $length, $data, $callback->($status) |
|
|
933 | |
|
|
934 | Opens, reads and closes the given file. The data is put into C<$data>, |
|
|
935 | which is resized as required. |
|
|
936 | |
|
|
937 | If C<$offset> is negative, then it is counted from the end of the file. |
|
|
938 | |
|
|
939 | If C<$length> is zero, then the remaining length of the file is |
|
|
940 | used. Also, in this case, the same limitations to modifying C<$data> apply |
|
|
941 | as when IO::AIO::mmap is used, i.e. it must only be modified in-place |
|
|
942 | with C<substr>. If the size of the file is known, specifying a non-zero |
|
|
943 | C<$length> results in a performance advantage. |
|
|
944 | |
|
|
945 | This request is similar to the older C<aio_load> request, but since it is |
|
|
946 | a single request, it might be more efficient to use. |
|
|
947 | |
|
|
948 | Example: load F</etc/passwd> into C<$passwd>. |
|
|
949 | |
|
|
950 | my $passwd; |
|
|
951 | aio_slurp "/etc/passwd", 0, 0, $passwd, sub { |
|
|
952 | $_[0] >= 0 |
|
|
953 | or die "/etc/passwd: $!\n"; |
|
|
954 | |
|
|
955 | printf "/etc/passwd is %d bytes long, and contains:\n", length $passwd; |
|
|
956 | print $passwd; |
|
|
957 | }; |
|
|
958 | IO::AIO::flush; |
|
|
959 | |
|
|
960 | |
| 809 | =item aio_load $pathname, $data, $callback->($status) |
961 | =item aio_load $pathname, $data, $callback->($status) |
| 810 | |
962 | |
| 811 | This is a composite request that tries to fully load the given file into |
963 | This is a composite request that tries to fully load the given file into |
| 812 | memory. Status is the same as with aio_read. |
964 | memory. Status is the same as with aio_read. |
|
|
965 | |
|
|
966 | Using C<aio_slurp> might be more efficient, as it is a single request. |
| 813 | |
967 | |
| 814 | =cut |
968 | =cut |
| 815 | |
969 | |
| 816 | sub aio_load($$;$) { |
970 | sub aio_load($$;$) { |
| 817 | my ($path, undef, $cb) = @_; |
971 | my ($path, undef, $cb) = @_; |
| … | |
… | |
| 837 | =item aio_copy $srcpath, $dstpath, $callback->($status) |
991 | =item aio_copy $srcpath, $dstpath, $callback->($status) |
| 838 | |
992 | |
| 839 | Try to copy the I<file> (directories not supported as either source or |
993 | Try to copy the I<file> (directories not supported as either source or |
| 840 | destination) from C<$srcpath> to C<$dstpath> and call the callback with |
994 | destination) from C<$srcpath> to C<$dstpath> and call the callback with |
| 841 | a status of C<0> (ok) or C<-1> (error, see C<$!>). |
995 | a status of C<0> (ok) or C<-1> (error, see C<$!>). |
|
|
996 | |
|
|
997 | Existing destination files will be truncated. |
| 842 | |
998 | |
| 843 | This is a composite request that creates the destination file with |
999 | This is a composite request that creates the destination file with |
| 844 | mode 0200 and copies the contents of the source file into it using |
1000 | mode 0200 and copies the contents of the source file into it using |
| 845 | C<aio_sendfile>, followed by restoring atime, mtime, access mode and |
1001 | C<aio_sendfile>, followed by restoring atime, mtime, access mode and |
| 846 | uid/gid, in that order. |
1002 | uid/gid, in that order. |
| … | |
… | |
| 956 | Scans a directory (similar to C<aio_readdir>) but additionally tries to |
1112 | Scans a directory (similar to C<aio_readdir>) but additionally tries to |
| 957 | efficiently separate the entries of directory C<$path> into two sets of |
1113 | efficiently separate the entries of directory C<$path> into two sets of |
| 958 | names, directories you can recurse into (directories), and ones you cannot |
1114 | names, directories you can recurse into (directories), and ones you cannot |
| 959 | recurse into (everything else, including symlinks to directories). |
1115 | recurse into (everything else, including symlinks to directories). |
| 960 | |
1116 | |
| 961 | C<aio_scandir> is a composite request that creates of many sub requests_ |
1117 | C<aio_scandir> is a composite request that generates many sub requests. |
| 962 | C<$maxreq> specifies the maximum number of outstanding aio requests that |
1118 | C<$maxreq> specifies the maximum number of outstanding aio requests that |
| 963 | this function generates. If it is C<< <= 0 >>, then a suitable default |
1119 | this function generates. If it is C<< <= 0 >>, then a suitable default |
| 964 | will be chosen (currently 4). |
1120 | will be chosen (currently 4). |
| 965 | |
1121 | |
| 966 | On error, the callback is called without arguments, otherwise it receives |
1122 | On error, the callback is called without arguments, otherwise it receives |
| … | |
… | |
| 1100 | } |
1256 | } |
| 1101 | |
1257 | |
| 1102 | =item aio_rmtree $pathname, $callback->($status) |
1258 | =item aio_rmtree $pathname, $callback->($status) |
| 1103 | |
1259 | |
| 1104 | Delete a directory tree starting (and including) C<$path>, return the |
1260 | Delete a directory tree starting (and including) C<$path>, return the |
| 1105 | status of the final C<rmdir> only. This is a composite request that |
1261 | status of the final C<rmdir> only. This is a composite request that |
| 1106 | uses C<aio_scandir> to recurse into and rmdir directories, and unlink |
1262 | uses C<aio_scandir> to recurse into and rmdir directories, and unlink |
| 1107 | everything else. |
1263 | everything else. |
| 1108 | |
1264 | |
| 1109 | =cut |
1265 | =cut |
| 1110 | |
1266 | |
| … | |
… | |
| 1131 | add $grp $dirgrp; |
1287 | add $grp $dirgrp; |
| 1132 | }; |
1288 | }; |
| 1133 | |
1289 | |
| 1134 | $grp |
1290 | $grp |
| 1135 | } |
1291 | } |
|
|
1292 | |
|
|
1293 | =item aio_fcntl $fh, $cmd, $arg, $callback->($status) |
|
|
1294 | |
|
|
1295 | =item aio_ioctl $fh, $request, $buf, $callback->($status) |
|
|
1296 | |
|
|
1297 | These work just like the C<fcntl> and C<ioctl> built-in functions, except |
|
|
1298 | they execute asynchronously and pass the return value to the callback. |
|
|
1299 | |
|
|
1300 | Both calls can be used for a lot of things, some of which make more sense |
|
|
1301 | to run asynchronously in their own thread, while some others make less |
|
|
1302 | sense. For example, calls that block waiting for external events, such |
|
|
1303 | as locking, will also lock down an I/O thread while it is waiting, which |
|
|
1304 | can deadlock the whole I/O system. At the same time, there might be no |
|
|
1305 | alternative to using a thread to wait. |
|
|
1306 | |
|
|
1307 | So in general, you should only use these calls for things that do |
|
|
1308 | (filesystem) I/O, not for things that wait for other events (network, |
|
|
1309 | other processes), although if you are careful and know what you are doing, |
|
|
1310 | you still can. |
|
|
1311 | |
|
|
1312 | The following constants are available (missing ones are, as usual C<0>): |
|
|
1313 | |
|
|
1314 | C<F_DUPFD_CLOEXEC>, |
|
|
1315 | |
|
|
1316 | C<F_OFD_GETLK>, C<F_OFD_SETLK>, C<F_OFD_GETLKW>, |
|
|
1317 | |
|
|
1318 | C<FIFREEZE>, C<FITHAW>, C<FITRIM>, C<FICLONE>, C<FICLONERANGE>, C<FIDEDUPERANGE>. |
|
|
1319 | |
|
|
1320 | C<FS_IOC_GETFLAGS>, C<FS_IOC_SETFLAGS>, C<FS_IOC_GETVERSION>, C<FS_IOC_SETVERSION>, |
|
|
1321 | C<FS_IOC_FIEMAP>. |
|
|
1322 | |
|
|
1323 | C<FS_IOC_FSGETXATTR>, C<FS_IOC_FSSETXATTR>, C<FS_IOC_SET_ENCRYPTION_POLICY>, |
|
|
1324 | C<FS_IOC_GET_ENCRYPTION_PWSALT>, C<FS_IOC_GET_ENCRYPTION_POLICY>, C<FS_KEY_DESCRIPTOR_SIZE>. |
|
|
1325 | |
|
|
1326 | C<FS_SECRM_FL>, C<FS_UNRM_FL>, C<FS_COMPR_FL>, C<FS_SYNC_FL>, C<FS_IMMUTABLE_FL>, |
|
|
1327 | C<FS_APPEND_FL>, C<FS_NODUMP_FL>, C<FS_NOATIME_FL>, C<FS_DIRTY_FL>, |
|
|
1328 | C<FS_COMPRBLK_FL>, C<FS_NOCOMP_FL>, C<FS_ENCRYPT_FL>, C<FS_BTREE_FL>, |
|
|
1329 | C<FS_INDEX_FL>, C<FS_JOURNAL_DATA_FL>, C<FS_NOTAIL_FL>, C<FS_DIRSYNC_FL>, C<FS_TOPDIR_FL>, |
|
|
1330 | C<FS_FL_USER_MODIFIABLE>. |
|
|
1331 | |
|
|
1332 | C<FS_XFLAG_REALTIME>, C<FS_XFLAG_PREALLOC>, C<FS_XFLAG_IMMUTABLE>, C<FS_XFLAG_APPEND>, |
|
|
1333 | C<FS_XFLAG_SYNC>, C<FS_XFLAG_NOATIME>, C<FS_XFLAG_NODUMP>, C<FS_XFLAG_RTINHERIT>, |
|
|
1334 | C<FS_XFLAG_PROJINHERIT>, C<FS_XFLAG_NOSYMLINKS>, C<FS_XFLAG_EXTSIZE>, C<FS_XFLAG_EXTSZINHERIT>, |
|
|
1335 | C<FS_XFLAG_NODEFRAG>, C<FS_XFLAG_FILESTREAM>, C<FS_XFLAG_DAX>, C<FS_XFLAG_HASATTR>, |
| 1136 | |
1336 | |
| 1137 | =item aio_sync $callback->($status) |
1337 | =item aio_sync $callback->($status) |
| 1138 | |
1338 | |
| 1139 | Asynchronously call sync and call the callback when finished. |
1339 | Asynchronously call sync and call the callback when finished. |
| 1140 | |
1340 | |
| … | |
… | |
| 1209 | }; |
1409 | }; |
| 1210 | |
1410 | |
| 1211 | $grp |
1411 | $grp |
| 1212 | } |
1412 | } |
| 1213 | |
1413 | |
| 1214 | =item aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
1414 | =item aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status) |
| 1215 | |
1415 | |
| 1216 | This is a rather advanced IO::AIO call, which only works on mmap(2)ed |
1416 | This is a rather advanced IO::AIO call, which only works on mmap(2)ed |
| 1217 | scalars (see the C<IO::AIO::mmap> function, although it also works on data |
1417 | scalars (see the C<IO::AIO::mmap> function, although it also works on data |
| 1218 | scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the |
1418 | scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the |
| 1219 | scalar must only be modified in-place while an aio operation is pending on |
1419 | scalar must only be modified in-place while an aio operation is pending on |
| … | |
… | |
| 1221 | |
1421 | |
| 1222 | It calls the C<msync> function of your OS, if available, with the memory |
1422 | It calls the C<msync> function of your OS, if available, with the memory |
| 1223 | area starting at C<$offset> in the string and ending C<$length> bytes |
1423 | area starting at C<$offset> in the string and ending C<$length> bytes |
| 1224 | later. If C<$length> is negative, counts from the end, and if C<$length> |
1424 | later. If C<$length> is negative, counts from the end, and if C<$length> |
| 1225 | is C<undef>, then it goes till the end of the string. The flags can be |
1425 | is C<undef>, then it goes till the end of the string. The flags can be |
| 1226 | a combination of C<IO::AIO::MS_ASYNC>, C<IO::AIO::MS_INVALIDATE> and |
1426 | either C<IO::AIO::MS_ASYNC> or C<IO::AIO::MS_SYNC>, plus an optional |
| 1227 | C<IO::AIO::MS_SYNC>. |
1427 | C<IO::AIO::MS_INVALIDATE>. |
| 1228 | |
1428 | |
| 1229 | =item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
1429 | =item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
| 1230 | |
1430 | |
| 1231 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
1431 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
| 1232 | scalars. |
1432 | scalars. |
| 1233 | |
1433 | |
| 1234 | It touches (reads or writes) all memory pages in the specified |
1434 | It touches (reads or writes) all memory pages in the specified |
| 1235 | range inside the scalar. All caveats and parameters are the same |
1435 | range inside the scalar. All caveats and parameters are the same |
| 1236 | as for C<aio_msync>, above, except for flags, which must be either |
1436 | as for C<aio_msync>, above, except for flags, which must be either |
| 1237 | C<0> (which reads all pages and ensures they are instantiated) or |
1437 | C<0> (which reads all pages and ensures they are instantiated) or |
| 1238 | C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and |
1438 | C<IO::AIO::MT_MODIFY>, which modifies the memory pages (by reading and |
| 1239 | writing an octet from it, which dirties the page). |
1439 | writing an octet from it, which dirties the page). |
| 1240 | |
1440 | |
| 1241 | =item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
1441 | =item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
| 1242 | |
1442 | |
| 1243 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
1443 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
| … | |
… | |
| 1277 | |
1477 | |
| 1278 | aio_mlockall IO::AIO::MCL_FUTURE; |
1478 | aio_mlockall IO::AIO::MCL_FUTURE; |
| 1279 | |
1479 | |
| 1280 | =item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents) |
1480 | =item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents) |
| 1281 | |
1481 | |
| 1282 | Queries the extents of the given file (by calling the Linux FIEMAP ioctl, |
1482 | Queries the extents of the given file (by calling the Linux C<FIEMAP> |
| 1283 | see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If the |
1483 | ioctl, see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If |
| 1284 | C<ioctl> is not available on your OS, then this request will fail with |
1484 | the ioctl is not available on your OS, then this request will fail with |
| 1285 | C<ENOSYS>. |
1485 | C<ENOSYS>. |
| 1286 | |
1486 | |
| 1287 | C<$start> is the starting offset to query extents for, C<$length> is the |
1487 | C<$start> is the starting offset to query extents for, C<$length> is the |
| 1288 | size of the range to query - if it is C<undef>, then the whole file will |
1488 | size of the range to query - if it is C<undef>, then the whole file will |
| 1289 | be queried. |
1489 | be queried. |
| … | |
… | |
| 1292 | C<IO::AIO::FIEMAP_FLAG_XATTR> - C<IO::AIO::FIEMAP_FLAGS_COMPAT> is also |
1492 | C<IO::AIO::FIEMAP_FLAG_XATTR> - C<IO::AIO::FIEMAP_FLAGS_COMPAT> is also |
| 1293 | exported), and is normally C<0> or C<IO::AIO::FIEMAP_FLAG_SYNC> to query |
1493 | exported), and is normally C<0> or C<IO::AIO::FIEMAP_FLAG_SYNC> to query |
| 1294 | the data portion. |
1494 | the data portion. |
| 1295 | |
1495 | |
| 1296 | C<$count> is the maximum number of extent records to return. If it is |
1496 | C<$count> is the maximum number of extent records to return. If it is |
| 1297 | C<undef>, then IO::AIO queries all extents of the file. As a very special |
1497 | C<undef>, then IO::AIO queries all extents of the range. As a very special |
| 1298 | case, if it is C<0>, then the callback receives the number of extents |
1498 | case, if it is C<0>, then the callback receives the number of extents |
| 1299 | instead of the extents themselves. |
1499 | instead of the extents themselves (which is unreliable, see below). |
| 1300 | |
1500 | |
| 1301 | If an error occurs, the callback receives no arguments. The special |
1501 | If an error occurs, the callback receives no arguments. The special |
| 1302 | C<errno> value C<IO::AIO::EBADR> is available to test for flag errors. |
1502 | C<errno> value C<IO::AIO::EBADR> is available to test for flag errors. |
| 1303 | |
1503 | |
| 1304 | Otherwise, the callback receives an array reference with extent |
1504 | Otherwise, the callback receives an array reference with extent |
| … | |
… | |
| 1306 | following members: |
1506 | following members: |
| 1307 | |
1507 | |
| 1308 | [$logical, $physical, $length, $flags] |
1508 | [$logical, $physical, $length, $flags] |
| 1309 | |
1509 | |
| 1310 | Flags is any combination of the following flag values (typically either C<0> |
1510 | Flags is any combination of the following flag values (typically either C<0> |
| 1311 | or C<IO::AIO::FIEMAP_EXTENT_LAST>): |
1511 | or C<IO::AIO::FIEMAP_EXTENT_LAST> (1)): |
| 1312 | |
1512 | |
| 1313 | C<IO::AIO::FIEMAP_EXTENT_LAST>, C<IO::AIO::FIEMAP_EXTENT_UNKNOWN>, |
1513 | C<IO::AIO::FIEMAP_EXTENT_LAST>, C<IO::AIO::FIEMAP_EXTENT_UNKNOWN>, |
| 1314 | C<IO::AIO::FIEMAP_EXTENT_DELALLOC>, C<IO::AIO::FIEMAP_EXTENT_ENCODED>, |
1514 | C<IO::AIO::FIEMAP_EXTENT_DELALLOC>, C<IO::AIO::FIEMAP_EXTENT_ENCODED>, |
| 1315 | C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>, |
1515 | C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>, |
| 1316 | C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>, |
1516 | C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>, |
| 1317 | C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or |
1517 | C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or |
| 1318 | C<IO::AIO::FIEMAP_EXTENT_SHARED>. |
1518 | C<IO::AIO::FIEMAP_EXTENT_SHARED>. |
| 1319 | |
1519 | |
|
|
1520 | At the time of this writing (Linux 3.2), this request is unreliable unless |
|
|
1521 | C<$count> is C<undef>, as the kernel has all sorts of bugs preventing |
|
|
1522 | it to return all extents of a range for files with a large number of |
|
|
1523 | extents. The code (only) works around all these issues if C<$count> is |
|
|
1524 | C<undef>. |
|
|
1525 | |
| 1320 | =item aio_group $callback->(...) |
1526 | =item aio_group $callback->(...) |
| 1321 | |
1527 | |
| 1322 | This is a very special aio request: Instead of doing something, it is a |
1528 | This is a very special aio request: Instead of doing something, it is a |
| 1323 | container for other aio requests, which is useful if you want to bundle |
1529 | container for other aio requests, which is useful if you want to bundle |
| 1324 | many requests into a single, composite, request with a definite callback |
1530 | many requests into a single, composite, request with a definite callback |
| … | |
… | |
| 1407 | aio_stat [$etcdir, "passwd"], sub { |
1613 | aio_stat [$etcdir, "passwd"], sub { |
| 1408 | # yay |
1614 | # yay |
| 1409 | }; |
1615 | }; |
| 1410 | }; |
1616 | }; |
| 1411 | |
1617 | |
| 1412 | That C<aio_wd> is a request and not a normal function shows that creating |
1618 | The fact that C<aio_wd> is a request and not a normal function shows that |
| 1413 | an IO::AIO::WD object is itself a potentially blocking operation, which is |
1619 | creating an IO::AIO::WD object is itself a potentially blocking operation, |
| 1414 | why it is done asynchronously. |
1620 | which is why it is done asynchronously. |
| 1415 | |
1621 | |
| 1416 | To stat the directory obtained with C<aio_wd> above, one could write |
1622 | To stat the directory obtained with C<aio_wd> above, one could write |
| 1417 | either of the following three request calls: |
1623 | either of the following three request calls: |
| 1418 | |
1624 | |
| 1419 | aio_lstat "/etc" , sub { ... # pathname as normal string |
1625 | aio_lstat "/etc" , sub { ... # pathname as normal string |
| … | |
… | |
| 1436 | There are some caveats: when directories get renamed (or deleted), the |
1642 | There are some caveats: when directories get renamed (or deleted), the |
| 1437 | pathname string doesn't change, so will point to the new directory (or |
1643 | pathname string doesn't change, so will point to the new directory (or |
| 1438 | nowhere at all), while the directory fd, if available on the system, |
1644 | nowhere at all), while the directory fd, if available on the system, |
| 1439 | will still point to the original directory. Most functions accepting a |
1645 | will still point to the original directory. Most functions accepting a |
| 1440 | pathname will use the directory fd on newer systems, and the string on |
1646 | pathname will use the directory fd on newer systems, and the string on |
| 1441 | older systems. Some functions (such as realpath) will always rely on the |
1647 | older systems. Some functions (such as C<aio_realpath>) will always rely on |
| 1442 | string form of the pathname. |
1648 | the string form of the pathname. |
| 1443 | |
1649 | |
| 1444 | So this fucntionality is mainly useful to get some protection against |
1650 | So this functionality is mainly useful to get some protection against |
| 1445 | C<chdir>, to easily get an absolute path out of a relative path for future |
1651 | C<chdir>, to easily get an absolute path out of a relative path for future |
| 1446 | reference, and to speed up doing many operations in the same directory |
1652 | reference, and to speed up doing many operations in the same directory |
| 1447 | (e.g. when stat'ing all files in a directory). |
1653 | (e.g. when stat'ing all files in a directory). |
| 1448 | |
1654 | |
| 1449 | The following functions implement this working directory abstraction: |
1655 | The following functions implement this working directory abstraction: |
| … | |
… | |
| 1462 | passing C<undef> as working directory component of a pathname fails the |
1668 | passing C<undef> as working directory component of a pathname fails the |
| 1463 | request with C<ENOENT>, there is often no need for error checking in the |
1669 | request with C<ENOENT>, there is often no need for error checking in the |
| 1464 | C<aio_wd> callback, as future requests using the value will fail in the |
1670 | C<aio_wd> callback, as future requests using the value will fail in the |
| 1465 | expected way. |
1671 | expected way. |
| 1466 | |
1672 | |
| 1467 | If this call isn't available because your OS lacks it or it couldn't be |
|
|
| 1468 | detected, it will be emulated by calling C<fsync> instead. |
|
|
| 1469 | |
|
|
| 1470 | =item IO::AIO::CWD |
1673 | =item IO::AIO::CWD |
| 1471 | |
1674 | |
| 1472 | This is a compiletime constant (object) that represents the process |
1675 | This is a compiletime constant (object) that represents the process |
| 1473 | current working directory. |
1676 | current working directory. |
| 1474 | |
1677 | |
| 1475 | Specifying this object as working directory object for a pathname is as |
1678 | Specifying this object as working directory object for a pathname is as if |
| 1476 | if the pathname would be specified directly, without a directory object, |
1679 | the pathname would be specified directly, without a directory object. For |
| 1477 | e.g., these calls are functionally identical: |
1680 | example, these calls are functionally identical: |
| 1478 | |
1681 | |
| 1479 | aio_stat "somefile", sub { ... }; |
1682 | aio_stat "somefile", sub { ... }; |
| 1480 | aio_stat [IO::AIO::CWD, "somefile"], sub { ... }; |
1683 | aio_stat [IO::AIO::CWD, "somefile"], sub { ... }; |
| 1481 | |
1684 | |
| 1482 | =back |
1685 | =back |
| 1483 | |
1686 | |
|
|
1687 | To recover the path associated with an IO::AIO::WD object, you can use |
|
|
1688 | C<aio_realpath>: |
|
|
1689 | |
|
|
1690 | aio_realpath $wd, sub { |
|
|
1691 | warn "path is $_[0]\n"; |
|
|
1692 | }; |
|
|
1693 | |
|
|
1694 | Currently, C<aio_statvfs> always, and C<aio_rename> and C<aio_rmdir> |
|
|
1695 | sometimes, fall back to using an absolue path. |
| 1484 | |
1696 | |
| 1485 | =head2 IO::AIO::REQ CLASS |
1697 | =head2 IO::AIO::REQ CLASS |
| 1486 | |
1698 | |
| 1487 | All non-aggregate C<aio_*> functions return an object of this class when |
1699 | All non-aggregate C<aio_*> functions return an object of this class when |
| 1488 | called in non-void context. |
1700 | called in non-void context. |
| … | |
… | |
| 1666 | |
1878 | |
| 1667 | See C<poll_cb> for an example. |
1879 | See C<poll_cb> for an example. |
| 1668 | |
1880 | |
| 1669 | =item IO::AIO::poll_cb |
1881 | =item IO::AIO::poll_cb |
| 1670 | |
1882 | |
| 1671 | Process some outstanding events on the result pipe. You have to call |
1883 | Process some requests that have reached the result phase (i.e. they have |
|
|
1884 | been executed but the results are not yet reported). You have to call |
|
|
1885 | this "regularly" to finish outstanding requests. |
|
|
1886 | |
| 1672 | this regularly. Returns C<0> if all events could be processed (or there |
1887 | Returns C<0> if all events could be processed (or there were no |
| 1673 | were no events to process), or C<-1> if it returned earlier for whatever |
1888 | events to process), or C<-1> if it returned earlier for whatever |
| 1674 | reason. Returns immediately when no events are outstanding. The amount of |
1889 | reason. Returns immediately when no events are outstanding. The amount |
| 1675 | events processed depends on the settings of C<IO::AIO::max_poll_req> and |
1890 | of events processed depends on the settings of C<IO::AIO::max_poll_req>, |
| 1676 | C<IO::AIO::max_poll_time>. |
1891 | C<IO::AIO::max_poll_time> and C<IO::AIO::max_outstanding>. |
| 1677 | |
1892 | |
| 1678 | If not all requests were processed for whatever reason, the filehandle |
1893 | If not all requests were processed for whatever reason, the poll file |
| 1679 | will still be ready when C<poll_cb> returns, so normally you don't have to |
1894 | descriptor will still be ready when C<poll_cb> returns, so normally you |
| 1680 | do anything special to have it called later. |
1895 | don't have to do anything special to have it called later. |
| 1681 | |
1896 | |
| 1682 | Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes |
1897 | Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes |
| 1683 | ready, it can be beneficial to call this function from loops which submit |
1898 | ready, it can be beneficial to call this function from loops which submit |
| 1684 | a lot of requests, to make sure the results get processed when they become |
1899 | a lot of requests, to make sure the results get processed when they become |
| 1685 | available and not just when the loop is finished and the event loop takes |
1900 | available and not just when the loop is finished and the event loop takes |
| … | |
… | |
| 1694 | poll => 'r', async => 1, |
1909 | poll => 'r', async => 1, |
| 1695 | cb => \&IO::AIO::poll_cb); |
1910 | cb => \&IO::AIO::poll_cb); |
| 1696 | |
1911 | |
| 1697 | =item IO::AIO::poll_wait |
1912 | =item IO::AIO::poll_wait |
| 1698 | |
1913 | |
| 1699 | If there are any outstanding requests and none of them in the result |
1914 | Wait until either at least one request is in the result phase or no |
| 1700 | phase, wait till the result filehandle becomes ready for reading (simply |
1915 | requests are outstanding anymore. |
| 1701 | does a C<select> on the filehandle. This is useful if you want to |
1916 | |
| 1702 | synchronously wait for some requests to finish). |
1917 | This is useful if you want to synchronously wait for some requests to |
|
|
1918 | become ready, without actually handling them. |
| 1703 | |
1919 | |
| 1704 | See C<nreqs> for an example. |
1920 | See C<nreqs> for an example. |
| 1705 | |
1921 | |
| 1706 | =item IO::AIO::poll |
1922 | =item IO::AIO::poll |
| 1707 | |
1923 | |
| … | |
… | |
| 1828 | |
2044 | |
| 1829 | This is a very bad function to use in interactive programs because it |
2045 | This is a very bad function to use in interactive programs because it |
| 1830 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
2046 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
| 1831 | use an C<aio_group> together with a feed callback. |
2047 | use an C<aio_group> together with a feed callback. |
| 1832 | |
2048 | |
| 1833 | It's main use is in scripts without an event loop - when you want to stat |
2049 | Its main use is in scripts without an event loop - when you want to stat |
| 1834 | a lot of files, you can write somehting like this: |
2050 | a lot of files, you can write something like this: |
| 1835 | |
2051 | |
| 1836 | IO::AIO::max_outstanding 32; |
2052 | IO::AIO::max_outstanding 32; |
| 1837 | |
2053 | |
| 1838 | for my $path (...) { |
2054 | for my $path (...) { |
| 1839 | aio_stat $path , ...; |
2055 | aio_stat $path , ...; |
| … | |
… | |
| 1878 | |
2094 | |
| 1879 | =back |
2095 | =back |
| 1880 | |
2096 | |
| 1881 | =head3 MISCELLANEOUS FUNCTIONS |
2097 | =head3 MISCELLANEOUS FUNCTIONS |
| 1882 | |
2098 | |
| 1883 | IO::AIO implements some functions that might be useful, but are not |
2099 | IO::AIO implements some functions that are useful when you want to use |
| 1884 | asynchronous. |
2100 | some "Advanced I/O" function not available to in Perl, without going the |
|
|
2101 | "Asynchronous I/O" route. Many of these have an asynchronous C<aio_*> |
|
|
2102 | counterpart. |
| 1885 | |
2103 | |
| 1886 | =over 4 |
2104 | =over 4 |
|
|
2105 | |
|
|
2106 | =item $numfd = IO::AIO::get_fdlimit |
|
|
2107 | |
|
|
2108 | This function is I<EXPERIMENTAL> and subject to change. |
|
|
2109 | |
|
|
2110 | Tries to find the current file descriptor limit and returns it, or |
|
|
2111 | C<undef> and sets C<$!> in case of an error. The limit is one larger than |
|
|
2112 | the highest valid file descriptor number. |
|
|
2113 | |
|
|
2114 | =item IO::AIO::min_fdlimit [$numfd] |
|
|
2115 | |
|
|
2116 | This function is I<EXPERIMENTAL> and subject to change. |
|
|
2117 | |
|
|
2118 | Try to increase the current file descriptor limit(s) to at least C<$numfd> |
|
|
2119 | by changing the soft or hard file descriptor resource limit. If C<$numfd> |
|
|
2120 | is missing, it will try to set a very high limit, although this is not |
|
|
2121 | recommended when you know the actual minimum that you require. |
|
|
2122 | |
|
|
2123 | If the limit cannot be raised enough, the function makes a best-effort |
|
|
2124 | attempt to increase the limit as much as possible, using various |
|
|
2125 | tricks, while still failing. You can query the resulting limit using |
|
|
2126 | C<IO::AIO::get_fdlimit>. |
|
|
2127 | |
|
|
2128 | If an error occurs, returns C<undef> and sets C<$!>, otherwise returns |
|
|
2129 | true. |
| 1887 | |
2130 | |
| 1888 | =item IO::AIO::sendfile $ofh, $ifh, $offset, $count |
2131 | =item IO::AIO::sendfile $ofh, $ifh, $offset, $count |
| 1889 | |
2132 | |
| 1890 | Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>, |
2133 | Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>, |
| 1891 | but is blocking (this makes most sense if you know the input data is |
2134 | but is blocking (this makes most sense if you know the input data is |
| … | |
… | |
| 1908 | =item IO::AIO::madvise $scalar, $offset, $len, $advice |
2151 | =item IO::AIO::madvise $scalar, $offset, $len, $advice |
| 1909 | |
2152 | |
| 1910 | Simply calls the C<posix_madvise> function (see its |
2153 | Simply calls the C<posix_madvise> function (see its |
| 1911 | manpage for details). The following advice constants are |
2154 | manpage for details). The following advice constants are |
| 1912 | available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>, |
2155 | available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>, |
| 1913 | C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>. |
2156 | C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, |
|
|
2157 | C<IO::AIO::MADV_DONTNEED>. |
|
|
2158 | |
|
|
2159 | If C<$offset> is negative, counts from the end. If C<$length> is negative, |
|
|
2160 | the remaining length of the C<$scalar> is used. If possible, C<$length> |
|
|
2161 | will be reduced to fit into the C<$scalar>. |
| 1914 | |
2162 | |
| 1915 | On systems that do not implement C<posix_madvise>, this function returns |
2163 | On systems that do not implement C<posix_madvise>, this function returns |
| 1916 | ENOSYS, otherwise the return value of C<posix_madvise>. |
2164 | ENOSYS, otherwise the return value of C<posix_madvise>. |
| 1917 | |
2165 | |
| 1918 | =item IO::AIO::mprotect $scalar, $offset, $len, $protect |
2166 | =item IO::AIO::mprotect $scalar, $offset, $len, $protect |
| … | |
… | |
| 1920 | Simply calls the C<mprotect> function on the preferably AIO::mmap'ed |
2168 | Simply calls the C<mprotect> function on the preferably AIO::mmap'ed |
| 1921 | $scalar (see its manpage for details). The following protect |
2169 | $scalar (see its manpage for details). The following protect |
| 1922 | constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>, |
2170 | constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>, |
| 1923 | C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>. |
2171 | C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>. |
| 1924 | |
2172 | |
|
|
2173 | If C<$offset> is negative, counts from the end. If C<$length> is negative, |
|
|
2174 | the remaining length of the C<$scalar> is used. If possible, C<$length> |
|
|
2175 | will be reduced to fit into the C<$scalar>. |
|
|
2176 | |
| 1925 | On systems that do not implement C<mprotect>, this function returns |
2177 | On systems that do not implement C<mprotect>, this function returns |
| 1926 | ENOSYS, otherwise the return value of C<mprotect>. |
2178 | ENOSYS, otherwise the return value of C<mprotect>. |
| 1927 | |
2179 | |
| 1928 | =item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
2180 | =item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
| 1929 | |
2181 | |
| 1930 | Memory-maps a file (or anonymous memory range) and attaches it to the |
2182 | Memory-maps a file (or anonymous memory range) and attaches it to the |
| 1931 | given C<$scalar>, which will act like a string scalar. Returns true on |
2183 | given C<$scalar>, which will act like a string scalar. Returns true on |
| 1932 | success, and false otherwise. |
2184 | success, and false otherwise. |
| 1933 | |
2185 | |
|
|
2186 | The scalar must exist, but its contents do not matter - this means you |
|
|
2187 | cannot use a nonexistant array or hash element. When in doubt, C<undef> |
|
|
2188 | the scalar first. |
|
|
2189 | |
| 1934 | The only operations allowed on the scalar are C<substr>/C<vec> that don't |
2190 | The only operations allowed on the mmapped scalar are C<substr>/C<vec>, |
| 1935 | change the string length, and most read-only operations such as copying it |
2191 | which don't change the string length, and most read-only operations such |
| 1936 | or searching it with regexes and so on. |
2192 | as copying it or searching it with regexes and so on. |
| 1937 | |
2193 | |
| 1938 | Anything else is unsafe and will, at best, result in memory leaks. |
2194 | Anything else is unsafe and will, at best, result in memory leaks. |
| 1939 | |
2195 | |
| 1940 | The memory map associated with the C<$scalar> is automatically removed |
2196 | The memory map associated with the C<$scalar> is automatically removed |
| 1941 | when the C<$scalar> is destroyed, or when the C<IO::AIO::mmap> or |
2197 | when the C<$scalar> is undef'd or destroyed, or when the C<IO::AIO::mmap> |
| 1942 | C<IO::AIO::munmap> functions are called. |
2198 | or C<IO::AIO::munmap> functions are called on it. |
| 1943 | |
2199 | |
| 1944 | This calls the C<mmap>(2) function internally. See your system's manual |
2200 | This calls the C<mmap>(2) function internally. See your system's manual |
| 1945 | page for details on the C<$length>, C<$prot> and C<$flags> parameters. |
2201 | page for details on the C<$length>, C<$prot> and C<$flags> parameters. |
| 1946 | |
2202 | |
| 1947 | The C<$length> must be larger than zero and smaller than the actual |
2203 | The C<$length> must be larger than zero and smaller than the actual |
| 1948 | filesize. |
2204 | filesize. |
| 1949 | |
2205 | |
| 1950 | C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>, |
2206 | C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>, |
| 1951 | C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>, |
2207 | C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>, |
| 1952 | |
2208 | |
| 1953 | C<$flags> can be a combination of C<IO::AIO::MAP_SHARED> or |
2209 | C<$flags> can be a combination of |
| 1954 | C<IO::AIO::MAP_PRIVATE>, or a number of system-specific flags (when |
2210 | C<IO::AIO::MAP_SHARED> or |
| 1955 | not available, the are defined as 0): C<IO::AIO::MAP_ANONYMOUS> |
2211 | C<IO::AIO::MAP_PRIVATE>, |
|
|
2212 | or a number of system-specific flags (when not available, the are C<0>): |
| 1956 | (which is set to C<MAP_ANON> if your system only provides this |
2213 | C<IO::AIO::MAP_ANONYMOUS> (which is set to C<MAP_ANON> if your system only provides this constant), |
| 1957 | constant), C<IO::AIO::MAP_HUGETLB>, C<IO::AIO::MAP_LOCKED>, |
2214 | C<IO::AIO::MAP_LOCKED>, |
| 1958 | C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or |
2215 | C<IO::AIO::MAP_NORESERVE>, |
|
|
2216 | C<IO::AIO::MAP_POPULATE>, |
| 1959 | C<IO::AIO::MAP_NONBLOCK> |
2217 | C<IO::AIO::MAP_NONBLOCK>, |
|
|
2218 | C<IO::AIO::MAP_FIXED>, |
|
|
2219 | C<IO::AIO::MAP_GROWSDOWN>, |
|
|
2220 | C<IO::AIO::MAP_32BIT>, |
|
|
2221 | C<IO::AIO::MAP_HUGETLB> or |
|
|
2222 | C<IO::AIO::MAP_STACK>. |
| 1960 | |
2223 | |
| 1961 | If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed. |
2224 | If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed. |
| 1962 | |
2225 | |
| 1963 | C<$offset> is the offset from the start of the file - it generally must be |
2226 | C<$offset> is the offset from the start of the file - it generally must be |
| 1964 | a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>. |
2227 | a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>. |
| … | |
… | |
| 2007 | |
2270 | |
| 2008 | See the C<splice(2)> manpage for details. |
2271 | See the C<splice(2)> manpage for details. |
| 2009 | |
2272 | |
| 2010 | =item IO::AIO::tee $r_fh, $w_fh, $length, $flags |
2273 | =item IO::AIO::tee $r_fh, $w_fh, $length, $flags |
| 2011 | |
2274 | |
| 2012 | Calls the GNU/Linux C<tee(2)> syscall, see it's manpage and the |
2275 | Calls the GNU/Linux C<tee(2)> syscall, see its manpage and the |
| 2013 | description for C<IO::AIO::splice> above for details. |
2276 | description for C<IO::AIO::splice> above for details. |
|
|
2277 | |
|
|
2278 | =item $actual_size = IO::AIO::pipesize $r_fh[, $new_size] |
|
|
2279 | |
|
|
2280 | Attempts to query or change the pipe buffer size. Obviously works only |
|
|
2281 | on pipes, and currently works only on GNU/Linux systems, and fails with |
|
|
2282 | C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer |
|
|
2283 | size on other systems, drop me a note. |
|
|
2284 | |
|
|
2285 | =item ($rfh, $wfh) = IO::AIO::pipe2 [$flags] |
|
|
2286 | |
|
|
2287 | This is a direct interface to the Linux L<pipe2(2)> system call. If |
|
|
2288 | C<$flags> is missing or C<0>, then this should be the same as a call to |
|
|
2289 | perl's built-in C<pipe> function and create a new pipe, and works on |
|
|
2290 | systems that lack the pipe2 syscall. On win32, this case invokes C<_pipe |
|
|
2291 | (..., 4096, O_BINARY)>. |
|
|
2292 | |
|
|
2293 | If C<$flags> is non-zero, it tries to invoke the pipe2 system call with |
|
|
2294 | the given flags (Linux 2.6.27, glibc 2.9). |
|
|
2295 | |
|
|
2296 | On success, the read and write file handles are returned. |
|
|
2297 | |
|
|
2298 | On error, nothing will be returned. If the pipe2 syscall is missing and |
|
|
2299 | C<$flags> is non-zero, fails with C<ENOSYS>. |
|
|
2300 | |
|
|
2301 | Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the |
|
|
2302 | time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and |
|
|
2303 | C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported. |
| 2014 | |
2304 | |
| 2015 | =back |
2305 | =back |
| 2016 | |
2306 | |
| 2017 | =cut |
2307 | =cut |
| 2018 | |
2308 | |
