… | |
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4 | |
4 | |
5 | =head1 SYNOPSIS |
5 | =head1 SYNOPSIS |
6 | |
6 | |
7 | use IO::AIO; |
7 | use IO::AIO; |
8 | |
8 | |
9 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
9 | aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub { |
10 | my $fh = shift |
10 | my $fh = shift |
11 | or die "/etc/passwd: $!"; |
11 | or die "/etc/passwd: $!"; |
12 | ... |
12 | ... |
13 | }; |
13 | }; |
14 | |
14 | |
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76 | |
76 | |
77 | # register the IO::AIO callback with EV |
77 | # register the IO::AIO callback with EV |
78 | my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb; |
78 | my $aio_w = EV::io IO::AIO::poll_fileno, EV::READ, \&IO::AIO::poll_cb; |
79 | |
79 | |
80 | # queue the request to open /etc/passwd |
80 | # queue the request to open /etc/passwd |
81 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
81 | aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub { |
82 | my $fh = shift |
82 | my $fh = shift |
83 | or die "error while opening: $!"; |
83 | or die "error while opening: $!"; |
84 | |
84 | |
85 | # stat'ing filehandles is generally non-blocking |
85 | # stat'ing filehandles is generally non-blocking |
86 | my $size = -s $fh; |
86 | my $size = -s $fh; |
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… | |
168 | use common::sense; |
168 | use common::sense; |
169 | |
169 | |
170 | use base 'Exporter'; |
170 | use base 'Exporter'; |
171 | |
171 | |
172 | BEGIN { |
172 | BEGIN { |
173 | our $VERSION = '3.5'; |
173 | our $VERSION = '4.0'; |
174 | |
174 | |
175 | our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close |
175 | our @AIO_REQ = qw(aio_sendfile aio_read aio_write aio_open aio_close |
176 | aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx |
176 | aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx |
177 | aio_scandir aio_symlink aio_readlink aio_sync aio_fsync |
177 | aio_scandir aio_symlink aio_readlink aio_realpath aio_sync |
178 | aio_fdatasync aio_sync_file_range aio_pathsync aio_readahead |
178 | aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range aio_fallocate |
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179 | aio_pathsync aio_readahead |
179 | aio_rename aio_link aio_move aio_copy aio_group |
180 | aio_rename aio_link aio_move aio_copy aio_group |
180 | aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown |
181 | aio_nop aio_mknod aio_load aio_rmtree aio_mkdir aio_chown |
181 | aio_chmod aio_utime aio_truncate |
182 | aio_chmod aio_utime aio_truncate |
182 | aio_msync aio_mtouch aio_statvfs); |
183 | aio_msync aio_mtouch aio_mlock aio_mlockall |
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184 | aio_statvfs |
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185 | aio_wd); |
183 | |
186 | |
184 | our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice)); |
187 | our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice)); |
185 | our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush |
188 | our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush |
186 | min_parallel max_parallel max_idle |
189 | min_parallel max_parallel max_idle idle_timeout |
187 | nreqs nready npending nthreads |
190 | nreqs nready npending nthreads |
188 | max_poll_time max_poll_reqs |
191 | max_poll_time max_poll_reqs |
189 | sendfile fadvise); |
192 | sendfile fadvise madvise |
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193 | mmap munmap munlock munlockall); |
190 | |
194 | |
191 | push @AIO_REQ, qw(aio_busy); # not exported |
195 | push @AIO_REQ, qw(aio_busy); # not exported |
192 | |
196 | |
193 | @IO::AIO::GRP::ISA = 'IO::AIO::REQ'; |
197 | @IO::AIO::GRP::ISA = 'IO::AIO::REQ'; |
194 | |
198 | |
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… | |
202 | |
206 | |
203 | This section simply lists the prototypes of the most important functions |
207 | This section simply lists the prototypes of the most important functions |
204 | for quick reference. See the following sections for function-by-function |
208 | for quick reference. See the following sections for function-by-function |
205 | documentation. |
209 | documentation. |
206 | |
210 | |
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211 | aio_wd $pathname, $callback->($wd) |
207 | aio_open $pathname, $flags, $mode, $callback->($fh) |
212 | aio_open $pathname, $flags, $mode, $callback->($fh) |
208 | aio_close $fh, $callback->($status) |
213 | aio_close $fh, $callback->($status) |
209 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
214 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
210 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
215 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
211 | aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval) |
216 | aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval) |
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216 | aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
221 | aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
217 | aio_chown $fh_or_path, $uid, $gid, $callback->($status) |
222 | aio_chown $fh_or_path, $uid, $gid, $callback->($status) |
218 | aio_truncate $fh_or_path, $offset, $callback->($status) |
223 | aio_truncate $fh_or_path, $offset, $callback->($status) |
219 | aio_chmod $fh_or_path, $mode, $callback->($status) |
224 | aio_chmod $fh_or_path, $mode, $callback->($status) |
220 | aio_unlink $pathname, $callback->($status) |
225 | aio_unlink $pathname, $callback->($status) |
221 | aio_mknod $path, $mode, $dev, $callback->($status) |
226 | aio_mknod $pathname, $mode, $dev, $callback->($status) |
222 | aio_link $srcpath, $dstpath, $callback->($status) |
227 | aio_link $srcpath, $dstpath, $callback->($status) |
223 | aio_symlink $srcpath, $dstpath, $callback->($status) |
228 | aio_symlink $srcpath, $dstpath, $callback->($status) |
224 | aio_readlink $path, $callback->($link) |
229 | aio_readlink $pathname, $callback->($link) |
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230 | aio_realpath $pathname, $callback->($link) |
225 | aio_rename $srcpath, $dstpath, $callback->($status) |
231 | aio_rename $srcpath, $dstpath, $callback->($status) |
226 | aio_mkdir $pathname, $mode, $callback->($status) |
232 | aio_mkdir $pathname, $mode, $callback->($status) |
227 | aio_rmdir $pathname, $callback->($status) |
233 | aio_rmdir $pathname, $callback->($status) |
228 | aio_readdir $pathname, $callback->($entries) |
234 | aio_readdir $pathname, $callback->($entries) |
229 | aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
235 | aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
230 | IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST |
236 | IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST |
231 | IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN |
237 | IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN |
232 | aio_load $path, $data, $callback->($status) |
238 | aio_load $pathname, $data, $callback->($status) |
233 | aio_copy $srcpath, $dstpath, $callback->($status) |
239 | aio_copy $srcpath, $dstpath, $callback->($status) |
234 | aio_move $srcpath, $dstpath, $callback->($status) |
240 | aio_move $srcpath, $dstpath, $callback->($status) |
235 | aio_scandir $path, $maxreq, $callback->($dirs, $nondirs) |
241 | aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs) |
236 | aio_rmtree $path, $callback->($status) |
242 | aio_rmtree $pathname, $callback->($status) |
237 | aio_sync $callback->($status) |
243 | aio_sync $callback->($status) |
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244 | aio_syncfs $fh, $callback->($status) |
238 | aio_fsync $fh, $callback->($status) |
245 | aio_fsync $fh, $callback->($status) |
239 | aio_fdatasync $fh, $callback->($status) |
246 | aio_fdatasync $fh, $callback->($status) |
240 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
247 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
241 | aio_pathsync $path, $callback->($status) |
248 | aio_pathsync $pathname, $callback->($status) |
242 | aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
249 | aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
243 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
250 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
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251 | aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
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252 | aio_mlockall $flags, $callback->($status) |
244 | aio_group $callback->(...) |
253 | aio_group $callback->(...) |
245 | aio_nop $callback->() |
254 | aio_nop $callback->() |
246 | |
255 | |
247 | $prev_pri = aioreq_pri [$pri] |
256 | $prev_pri = aioreq_pri [$pri] |
248 | aioreq_nice $pri_adjust |
257 | aioreq_nice $pri_adjust |
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254 | IO::AIO::max_poll_reqs $nreqs |
263 | IO::AIO::max_poll_reqs $nreqs |
255 | IO::AIO::max_poll_time $seconds |
264 | IO::AIO::max_poll_time $seconds |
256 | IO::AIO::min_parallel $nthreads |
265 | IO::AIO::min_parallel $nthreads |
257 | IO::AIO::max_parallel $nthreads |
266 | IO::AIO::max_parallel $nthreads |
258 | IO::AIO::max_idle $nthreads |
267 | IO::AIO::max_idle $nthreads |
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268 | IO::AIO::idle_timeout $seconds |
259 | IO::AIO::max_outstanding $maxreqs |
269 | IO::AIO::max_outstanding $maxreqs |
260 | IO::AIO::nreqs |
270 | IO::AIO::nreqs |
261 | IO::AIO::nready |
271 | IO::AIO::nready |
262 | IO::AIO::npending |
272 | IO::AIO::npending |
263 | |
273 | |
264 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
274 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
265 | IO::AIO::fadvise $fh, $offset, $len, $advice |
275 | IO::AIO::fadvise $fh, $offset, $len, $advice |
266 | IO::AIO::mlockall $flags |
276 | IO::AIO::madvise $scalar, $offset, $length, $advice |
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277 | IO::AIO::mprotect $scalar, $offset, $length, $protect |
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278 | IO::AIO::munlock $scalar, $offset = 0, $length = undef |
267 | IO::AIO::munlockall |
279 | IO::AIO::munlockall |
268 | |
280 | |
269 | =head2 AIO REQUEST FUNCTIONS |
281 | =head2 AIO REQUEST FUNCTIONS |
270 | |
282 | |
271 | All the C<aio_*> calls are more or less thin wrappers around the syscall |
283 | All the C<aio_*> calls are more or less thin wrappers around the syscall |
… | |
… | |
280 | internally until the request has finished. |
292 | internally until the request has finished. |
281 | |
293 | |
282 | All functions return request objects of type L<IO::AIO::REQ> that allow |
294 | All functions return request objects of type L<IO::AIO::REQ> that allow |
283 | further manipulation of those requests while they are in-flight. |
295 | further manipulation of those requests while they are in-flight. |
284 | |
296 | |
285 | The pathnames you pass to these routines I<must> be absolute and |
297 | The pathnames you pass to these routines I<should> be absolute. The |
286 | encoded as octets. The reason for the former is that at the time the |
298 | reason for this is that at the time the request is being executed, the |
287 | request is being executed, the current working directory could have |
299 | current working directory could have changed. Alternatively, you can make |
288 | changed. Alternatively, you can make sure that you never change the |
300 | sure that you never change the current working directory anywhere in |
289 | current working directory anywhere in the program and then use relative |
301 | the program and then use relative paths. Lastly, you can take advantage |
290 | paths. |
302 | of IO::AIOs working directory abstraction - see the description of the |
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303 | C<IO::AIO::WD> class later in this document. |
291 | |
304 | |
292 | To encode pathnames as octets, either make sure you either: a) always pass |
305 | To encode pathnames as octets, either make sure you either: a) always pass |
293 | in filenames you got from outside (command line, readdir etc.) without |
306 | in filenames you got from outside (command line, readdir etc.) without |
294 | tinkering, b) are ASCII or ISO 8859-1, c) use the Encode module and encode |
307 | tinkering, b) are ASCII or ISO 8859-1, c) use the Encode module and encode |
295 | your pathnames to the locale (or other) encoding in effect in the user |
308 | your pathnames to the locale (or other) encoding in effect in the user |
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… | |
352 | by the umask in effect then the request is being executed, so better never |
365 | by the umask in effect then the request is being executed, so better never |
353 | change the umask. |
366 | change the umask. |
354 | |
367 | |
355 | Example: |
368 | Example: |
356 | |
369 | |
357 | aio_open "/etc/passwd", O_RDONLY, 0, sub { |
370 | aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub { |
358 | if ($_[0]) { |
371 | if ($_[0]) { |
359 | print "open successful, fh is $_[0]\n"; |
372 | print "open successful, fh is $_[0]\n"; |
360 | ... |
373 | ... |
361 | } else { |
374 | } else { |
362 | die "open failed: $!\n"; |
375 | die "open failed: $!\n"; |
363 | } |
376 | } |
364 | }; |
377 | }; |
365 | |
378 | |
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379 | In addition to all the common open modes/flags (C<O_RDONLY>, C<O_WRONLY>, |
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380 | C<O_RDWR>, C<O_CREAT>, C<O_TRUNC>, C<O_EXCL> and C<O_APPEND>), the |
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381 | following POSIX and non-POSIX constants are available (missing ones on |
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382 | your system are, as usual, C<0>): |
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383 | |
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384 | C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>, |
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385 | C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>, |
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386 | C<O_RSYNC>, C<O_SYNC> and C<O_TTY_INIT>. |
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387 | |
366 | |
388 | |
367 | =item aio_close $fh, $callback->($status) |
389 | =item aio_close $fh, $callback->($status) |
368 | |
390 | |
369 | Asynchronously close a file and call the callback with the result |
391 | Asynchronously close a file and call the callback with the result |
370 | code. |
392 | code. |
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420 | |
442 | |
421 | Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts |
443 | Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts |
422 | reading at byte offset C<$in_offset>, and starts writing at the current |
444 | reading at byte offset C<$in_offset>, and starts writing at the current |
423 | file offset of C<$out_fh>. Because of that, it is not safe to issue more |
445 | file offset of C<$out_fh>. Because of that, it is not safe to issue more |
424 | than one C<aio_sendfile> per C<$out_fh>, as they will interfere with each |
446 | than one C<aio_sendfile> per C<$out_fh>, as they will interfere with each |
425 | other. |
447 | other. The same C<$in_fh> works fine though, as this function does not |
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448 | move or use the file offset of C<$in_fh>. |
426 | |
449 | |
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450 | Please note that C<aio_sendfile> can read more bytes from C<$in_fh> than |
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451 | are written, and there is no way to find out how many more bytes have been |
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452 | read from C<aio_sendfile> alone, as C<aio_sendfile> only provides the |
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453 | number of bytes written to C<$out_fh>. Only if the result value equals |
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454 | C<$length> one can assume that C<$length> bytes have been read. |
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455 | |
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456 | Unlike with other C<aio_> functions, it makes a lot of sense to use |
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457 | C<aio_sendfile> on non-blocking sockets, as long as one end (typically |
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458 | the C<$in_fh>) is a file - the file I/O will then be asynchronous, while |
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459 | the socket I/O will be non-blocking. Note, however, that you can run |
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460 | into a trap where C<aio_sendfile> reads some data with readahead, then |
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461 | fails to write all data, and when the socket is ready the next time, the |
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462 | data in the cache is already lost, forcing C<aio_sendfile> to again hit |
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463 | the disk. Explicit C<aio_read> + C<aio_write> let's you better control |
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464 | resource usage. |
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465 | |
427 | This call tries to make use of a native C<sendfile> syscall to provide |
466 | This call tries to make use of a native C<sendfile>-like syscall to |
428 | zero-copy operation. For this to work, C<$out_fh> should refer to a |
467 | provide zero-copy operation. For this to work, C<$out_fh> should refer to |
429 | socket, and C<$in_fh> should refer to an mmap'able file. |
468 | a socket, and C<$in_fh> should refer to an mmap'able file. |
430 | |
469 | |
431 | If a native sendfile cannot be found or it fails with C<ENOSYS>, |
470 | If a native sendfile cannot be found or it fails with C<ENOSYS>, |
432 | C<ENOTSUP>, C<EOPNOTSUPP>, C<EAFNOSUPPORT>, C<EPROTOTYPE> or C<ENOTSOCK>, |
471 | C<EINVAL>, C<ENOTSUP>, C<EOPNOTSUPP>, C<EAFNOSUPPORT>, C<EPROTOTYPE> or |
433 | it will be emulated, so you can call C<aio_sendfile> on any type of |
472 | C<ENOTSOCK>, it will be emulated, so you can call C<aio_sendfile> on any |
434 | filehandle regardless of the limitations of the operating system. |
473 | type of filehandle regardless of the limitations of the operating system. |
435 | |
474 | |
436 | Please note, however, that C<aio_sendfile> can read more bytes from |
475 | As native sendfile syscalls (as practically any non-POSIX interface hacked |
437 | C<$in_fh> than are written, and there is no way to find out how many |
476 | together in a hurry to improve benchmark numbers) tend to be rather buggy |
438 | bytes have been read from C<aio_sendfile> alone, as C<aio_sendfile> only |
477 | on many systems, this implementation tries to work around some known bugs |
439 | provides the number of bytes written to C<$out_fh>. Only if the result |
478 | in Linux and FreeBSD kernels (probably others, too), but that might fail, |
440 | value equals C<$length> one can assume that C<$length> bytes have been |
479 | so you really really should check the return value of C<aio_sendfile> - |
441 | read. |
480 | fewre bytes than expected might have been transferred. |
442 | |
481 | |
443 | |
482 | |
444 | =item aio_readahead $fh,$offset,$length, $callback->($retval) |
483 | =item aio_readahead $fh,$offset,$length, $callback->($retval) |
445 | |
484 | |
446 | C<aio_readahead> populates the page cache with data from a file so that |
485 | C<aio_readahead> populates the page cache with data from a file so that |
… | |
… | |
468 | for an explanation. |
507 | for an explanation. |
469 | |
508 | |
470 | Currently, the stats are always 64-bit-stats, i.e. instead of returning an |
509 | Currently, the stats are always 64-bit-stats, i.e. instead of returning an |
471 | error when stat'ing a large file, the results will be silently truncated |
510 | error when stat'ing a large file, the results will be silently truncated |
472 | unless perl itself is compiled with large file support. |
511 | unless perl itself is compiled with large file support. |
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512 | |
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513 | To help interpret the mode and dev/rdev stat values, IO::AIO offers the |
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514 | following constants and functions (if not implemented, the constants will |
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515 | be C<0> and the functions will either C<croak> or fall back on traditional |
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516 | behaviour). |
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517 | |
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518 | C<S_IFMT>, C<S_IFIFO>, C<S_IFCHR>, C<S_IFBLK>, C<S_IFLNK>, C<S_IFREG>, |
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519 | C<S_IFDIR>, C<S_IFWHT>, C<S_IFSOCK>, C<IO::AIO::major $dev_t>, |
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520 | C<IO::AIO::minor $dev_t>, C<IO::AIO::makedev $major, $minor>. |
473 | |
521 | |
474 | Example: Print the length of F</etc/passwd>: |
522 | Example: Print the length of F</etc/passwd>: |
475 | |
523 | |
476 | aio_stat "/etc/passwd", sub { |
524 | aio_stat "/etc/passwd", sub { |
477 | $_[0] and die "stat failed: $!"; |
525 | $_[0] and die "stat failed: $!"; |
… | |
… | |
569 | |
617 | |
570 | Asynchronously unlink (delete) a file and call the callback with the |
618 | Asynchronously unlink (delete) a file and call the callback with the |
571 | result code. |
619 | result code. |
572 | |
620 | |
573 | |
621 | |
574 | =item aio_mknod $path, $mode, $dev, $callback->($status) |
622 | =item aio_mknod $pathname, $mode, $dev, $callback->($status) |
575 | |
623 | |
576 | [EXPERIMENTAL] |
624 | [EXPERIMENTAL] |
577 | |
625 | |
578 | Asynchronously create a device node (or fifo). See mknod(2). |
626 | Asynchronously create a device node (or fifo). See mknod(2). |
579 | |
627 | |
580 | The only (POSIX-) portable way of calling this function is: |
628 | The only (POSIX-) portable way of calling this function is: |
581 | |
629 | |
582 | aio_mknod $path, IO::AIO::S_IFIFO | $mode, 0, sub { ... |
630 | aio_mknod $pathname, IO::AIO::S_IFIFO | $mode, 0, sub { ... |
583 | |
631 | |
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632 | See C<aio_stat> for info about some potentially helpful extra constants |
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633 | and functions. |
584 | |
634 | |
585 | =item aio_link $srcpath, $dstpath, $callback->($status) |
635 | =item aio_link $srcpath, $dstpath, $callback->($status) |
586 | |
636 | |
587 | Asynchronously create a new link to the existing object at C<$srcpath> at |
637 | Asynchronously create a new link to the existing object at C<$srcpath> at |
588 | the path C<$dstpath> and call the callback with the result code. |
638 | the path C<$dstpath> and call the callback with the result code. |
… | |
… | |
592 | |
642 | |
593 | Asynchronously create a new symbolic link to the existing object at C<$srcpath> at |
643 | Asynchronously create a new symbolic link to the existing object at C<$srcpath> at |
594 | the path C<$dstpath> and call the callback with the result code. |
644 | the path C<$dstpath> and call the callback with the result code. |
595 | |
645 | |
596 | |
646 | |
597 | =item aio_readlink $path, $callback->($link) |
647 | =item aio_readlink $pathname, $callback->($link) |
598 | |
648 | |
599 | Asynchronously read the symlink specified by C<$path> and pass it to |
649 | Asynchronously read the symlink specified by C<$path> and pass it to |
600 | the callback. If an error occurs, nothing or undef gets passed to the |
650 | the callback. If an error occurs, nothing or undef gets passed to the |
601 | callback. |
651 | callback. |
602 | |
652 | |
603 | |
653 | |
|
|
654 | =item aio_realpath $pathname, $callback->($path) |
|
|
655 | |
|
|
656 | Asynchronously make the path absolute and resolve any symlinks in |
|
|
657 | C<$path>. The resulting path only consists of directories (Same as |
|
|
658 | L<Cwd::realpath>). |
|
|
659 | |
|
|
660 | This request can be used to get the absolute path of the current working |
|
|
661 | directory by passing it a path of F<.> (a single dot). |
|
|
662 | |
|
|
663 | |
604 | =item aio_rename $srcpath, $dstpath, $callback->($status) |
664 | =item aio_rename $srcpath, $dstpath, $callback->($status) |
605 | |
665 | |
606 | Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as |
666 | Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as |
607 | rename(2) and call the callback with the result code. |
667 | rename(2) and call the callback with the result code. |
608 | |
668 | |
… | |
… | |
630 | array-ref with the filenames. |
690 | array-ref with the filenames. |
631 | |
691 | |
632 | |
692 | |
633 | =item aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
693 | =item aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
634 | |
694 | |
635 | Quite similar to C<aio_readdir>, but the C<$flags> argument allows to tune |
695 | Quite similar to C<aio_readdir>, but the C<$flags> argument allows one to |
636 | behaviour and output format. In case of an error, C<$entries> will be |
696 | tune behaviour and output format. In case of an error, C<$entries> will be |
637 | C<undef>. |
697 | C<undef>. |
638 | |
698 | |
639 | The flags are a combination of the following constants, ORed together (the |
699 | The flags are a combination of the following constants, ORed together (the |
640 | flags will also be passed to the callback, possibly modified): |
700 | flags will also be passed to the callback, possibly modified): |
641 | |
701 | |
642 | =over 4 |
702 | =over 4 |
643 | |
703 | |
644 | =item IO::AIO::READDIR_DENTS |
704 | =item IO::AIO::READDIR_DENTS |
645 | |
705 | |
646 | When this flag is off, then the callback gets an arrayref with of names |
706 | When this flag is off, then the callback gets an arrayref consisting of |
647 | only (as with C<aio_readdir>), otherwise it gets an arrayref with |
707 | names only (as with C<aio_readdir>), otherwise it gets an arrayref with |
648 | C<[$name, $type, $inode]> arrayrefs, each describing a single directory |
708 | C<[$name, $type, $inode]> arrayrefs, each describing a single directory |
649 | entry in more detail. |
709 | entry in more detail. |
650 | |
710 | |
651 | C<$name> is the name of the entry. |
711 | C<$name> is the name of the entry. |
652 | |
712 | |
… | |
… | |
665 | systems that do not deliver the inode information. |
725 | systems that do not deliver the inode information. |
666 | |
726 | |
667 | =item IO::AIO::READDIR_DIRS_FIRST |
727 | =item IO::AIO::READDIR_DIRS_FIRST |
668 | |
728 | |
669 | When this flag is set, then the names will be returned in an order where |
729 | When this flag is set, then the names will be returned in an order where |
670 | likely directories come first. This is useful when you need to quickly |
730 | likely directories come first, in optimal stat order. This is useful when |
671 | find directories, or you want to find all directories while avoiding to |
731 | you need to quickly find directories, or you want to find all directories |
672 | stat() each entry. |
732 | while avoiding to stat() each entry. |
673 | |
733 | |
674 | If the system returns type information in readdir, then this is used |
734 | If the system returns type information in readdir, then this is used |
675 | to find directories directly. Otherwise, likely directories are files |
735 | to find directories directly. Otherwise, likely directories are names |
676 | beginning with ".", or otherwise files with no dots, of which files with |
736 | beginning with ".", or otherwise names with no dots, of which names with |
677 | short names are tried first. |
737 | short names are tried first. |
678 | |
738 | |
679 | =item IO::AIO::READDIR_STAT_ORDER |
739 | =item IO::AIO::READDIR_STAT_ORDER |
680 | |
740 | |
681 | When this flag is set, then the names will be returned in an order |
741 | When this flag is set, then the names will be returned in an order |
… | |
… | |
688 | |
748 | |
689 | =item IO::AIO::READDIR_FOUND_UNKNOWN |
749 | =item IO::AIO::READDIR_FOUND_UNKNOWN |
690 | |
750 | |
691 | This flag should not be set when calling C<aio_readdirx>. Instead, it |
751 | This flag should not be set when calling C<aio_readdirx>. Instead, it |
692 | is being set by C<aio_readdirx>, when any of the C<$type>'s found were |
752 | is being set by C<aio_readdirx>, when any of the C<$type>'s found were |
693 | C<IO::AIO::DT_UNKNOWN>. The absense of this flag therefore indicates that all |
753 | C<IO::AIO::DT_UNKNOWN>. The absence of this flag therefore indicates that all |
694 | C<$type>'s are known, which can be used to speed up some algorithms. |
754 | C<$type>'s are known, which can be used to speed up some algorithms. |
695 | |
755 | |
696 | =back |
756 | =back |
697 | |
757 | |
698 | |
758 | |
699 | =item aio_load $path, $data, $callback->($status) |
759 | =item aio_load $pathname, $data, $callback->($status) |
700 | |
760 | |
701 | This is a composite request that tries to fully load the given file into |
761 | This is a composite request that tries to fully load the given file into |
702 | memory. Status is the same as with aio_read. |
762 | memory. Status is the same as with aio_read. |
703 | |
763 | |
704 | =cut |
764 | =cut |
… | |
… | |
826 | if ($_[0] && $! == EXDEV) { |
886 | if ($_[0] && $! == EXDEV) { |
827 | aioreq_pri $pri; |
887 | aioreq_pri $pri; |
828 | add $grp aio_copy $src, $dst, sub { |
888 | add $grp aio_copy $src, $dst, sub { |
829 | $grp->result ($_[0]); |
889 | $grp->result ($_[0]); |
830 | |
890 | |
831 | if (!$_[0]) { |
891 | unless ($_[0]) { |
832 | aioreq_pri $pri; |
892 | aioreq_pri $pri; |
833 | add $grp aio_unlink $src; |
893 | add $grp aio_unlink $src; |
834 | } |
894 | } |
835 | }; |
895 | }; |
836 | } else { |
896 | } else { |
… | |
… | |
839 | }; |
899 | }; |
840 | |
900 | |
841 | $grp |
901 | $grp |
842 | } |
902 | } |
843 | |
903 | |
844 | =item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs) |
904 | =item aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs) |
845 | |
905 | |
846 | Scans a directory (similar to C<aio_readdir>) but additionally tries to |
906 | Scans a directory (similar to C<aio_readdir>) but additionally tries to |
847 | efficiently separate the entries of directory C<$path> into two sets of |
907 | efficiently separate the entries of directory C<$path> into two sets of |
848 | names, directories you can recurse into (directories), and ones you cannot |
908 | names, directories you can recurse into (directories), and ones you cannot |
849 | recurse into (everything else, including symlinks to directories). |
909 | recurse into (everything else, including symlinks to directories). |
… | |
… | |
880 | Then entries will be sorted into likely directories a non-initial dot |
940 | Then entries will be sorted into likely directories a non-initial dot |
881 | currently) and likely non-directories (see C<aio_readdirx>). Then every |
941 | currently) and likely non-directories (see C<aio_readdirx>). Then every |
882 | entry plus an appended C</.> will be C<stat>'ed, likely directories first, |
942 | entry plus an appended C</.> will be C<stat>'ed, likely directories first, |
883 | in order of their inode numbers. If that succeeds, it assumes that the |
943 | in order of their inode numbers. If that succeeds, it assumes that the |
884 | entry is a directory or a symlink to directory (which will be checked |
944 | entry is a directory or a symlink to directory (which will be checked |
885 | seperately). This is often faster than stat'ing the entry itself because |
945 | separately). This is often faster than stat'ing the entry itself because |
886 | filesystems might detect the type of the entry without reading the inode |
946 | filesystems might detect the type of the entry without reading the inode |
887 | data (e.g. ext2fs filetype feature), even on systems that cannot return |
947 | data (e.g. ext2fs filetype feature), even on systems that cannot return |
888 | the filetype information on readdir. |
948 | the filetype information on readdir. |
889 | |
949 | |
890 | If the known number of directories (link count - 2) has been reached, the |
950 | If the known number of directories (link count - 2) has been reached, the |
… | |
… | |
906 | |
966 | |
907 | my $grp = aio_group $cb; |
967 | my $grp = aio_group $cb; |
908 | |
968 | |
909 | $maxreq = 4 if $maxreq <= 0; |
969 | $maxreq = 4 if $maxreq <= 0; |
910 | |
970 | |
911 | # stat once |
971 | # get a wd object |
|
|
972 | |
912 | aioreq_pri $pri; |
973 | aioreq_pri $pri; |
913 | add $grp aio_stat $path, sub { |
974 | add $grp aio_wd $path, sub { |
914 | return $grp->result () if $_[0]; |
975 | my $wd = [shift, "."]; |
915 | my $now = time; |
|
|
916 | my $hash1 = join ":", (stat _)[0,1,3,7,9]; |
|
|
917 | |
976 | |
918 | # read the directory entries |
977 | # stat once |
919 | aioreq_pri $pri; |
978 | aioreq_pri $pri; |
920 | add $grp aio_readdirx $path, READDIR_DIRS_FIRST, sub { |
979 | add $grp aio_stat $wd, sub { |
921 | my $entries = shift |
|
|
922 | or return $grp->result (); |
980 | return $grp->result () if $_[0]; |
|
|
981 | my $now = time; |
|
|
982 | my $hash1 = join ":", (stat _)[0,1,3,7,9]; |
923 | |
983 | |
924 | # stat the dir another time |
984 | # read the directory entries |
925 | aioreq_pri $pri; |
985 | aioreq_pri $pri; |
|
|
986 | add $grp aio_readdirx $wd, READDIR_DIRS_FIRST, sub { |
|
|
987 | my $entries = shift |
|
|
988 | or return $grp->result (); |
|
|
989 | |
|
|
990 | # stat the dir another time |
|
|
991 | aioreq_pri $pri; |
926 | add $grp aio_stat $path, sub { |
992 | add $grp aio_stat $wd, sub { |
927 | my $hash2 = join ":", (stat _)[0,1,3,7,9]; |
993 | my $hash2 = join ":", (stat _)[0,1,3,7,9]; |
928 | |
994 | |
929 | my $ndirs; |
995 | my $ndirs; |
930 | |
996 | |
931 | # take the slow route if anything looks fishy |
997 | # take the slow route if anything looks fishy |
932 | if ($hash1 ne $hash2 or (stat _)[9] == $now) { |
998 | if ($hash1 ne $hash2 or (stat _)[9] == $now) { |
933 | $ndirs = -1; |
999 | $ndirs = -1; |
934 | } else { |
1000 | } else { |
935 | # if nlink == 2, we are finished |
1001 | # if nlink == 2, we are finished |
936 | # for non-posix-fs's, we rely on nlink < 2 |
1002 | # for non-posix-fs's, we rely on nlink < 2 |
937 | $ndirs = (stat _)[3] - 2 |
1003 | $ndirs = (stat _)[3] - 2 |
938 | or return $grp->result ([], $entries); |
1004 | or return $grp->result ([], $entries); |
939 | } |
1005 | } |
940 | |
1006 | |
941 | my (@dirs, @nondirs); |
1007 | my (@dirs, @nondirs); |
942 | |
1008 | |
943 | my $statgrp = add $grp aio_group sub { |
1009 | my $statgrp = add $grp aio_group sub { |
944 | $grp->result (\@dirs, \@nondirs); |
1010 | $grp->result (\@dirs, \@nondirs); |
945 | }; |
1011 | }; |
946 | |
1012 | |
947 | limit $statgrp $maxreq; |
1013 | limit $statgrp $maxreq; |
948 | feed $statgrp sub { |
1014 | feed $statgrp sub { |
949 | return unless @$entries; |
1015 | return unless @$entries; |
950 | my $entry = shift @$entries; |
1016 | my $entry = shift @$entries; |
951 | |
1017 | |
952 | aioreq_pri $pri; |
1018 | aioreq_pri $pri; |
|
|
1019 | $wd->[1] = "$entry/."; |
953 | add $statgrp aio_stat "$path/$entry/.", sub { |
1020 | add $statgrp aio_stat $wd, sub { |
954 | if ($_[0] < 0) { |
1021 | if ($_[0] < 0) { |
955 | push @nondirs, $entry; |
1022 | push @nondirs, $entry; |
956 | } else { |
1023 | } else { |
957 | # need to check for real directory |
1024 | # need to check for real directory |
958 | aioreq_pri $pri; |
1025 | aioreq_pri $pri; |
|
|
1026 | $wd->[1] = $entry; |
959 | add $statgrp aio_lstat "$path/$entry", sub { |
1027 | add $statgrp aio_lstat $wd, sub { |
960 | if (-d _) { |
1028 | if (-d _) { |
961 | push @dirs, $entry; |
1029 | push @dirs, $entry; |
962 | |
1030 | |
963 | unless (--$ndirs) { |
1031 | unless (--$ndirs) { |
964 | push @nondirs, @$entries; |
1032 | push @nondirs, @$entries; |
965 | feed $statgrp; |
1033 | feed $statgrp; |
|
|
1034 | } |
|
|
1035 | } else { |
|
|
1036 | push @nondirs, $entry; |
966 | } |
1037 | } |
967 | } else { |
|
|
968 | push @nondirs, $entry; |
|
|
969 | } |
1038 | } |
970 | } |
1039 | } |
971 | } |
1040 | }; |
972 | }; |
1041 | }; |
973 | }; |
1042 | }; |
974 | }; |
1043 | }; |
975 | }; |
1044 | }; |
976 | }; |
1045 | }; |
977 | |
1046 | |
978 | $grp |
1047 | $grp |
979 | } |
1048 | } |
980 | |
1049 | |
981 | =item aio_rmtree $path, $callback->($status) |
1050 | =item aio_rmtree $pathname, $callback->($status) |
982 | |
1051 | |
983 | Delete a directory tree starting (and including) C<$path>, return the |
1052 | Delete a directory tree starting (and including) C<$path>, return the |
984 | status of the final C<rmdir> only. This is a composite request that |
1053 | status of the final C<rmdir> only. This is a composite request that |
985 | uses C<aio_scandir> to recurse into and rmdir directories, and unlink |
1054 | uses C<aio_scandir> to recurse into and rmdir directories, and unlink |
986 | everything else. |
1055 | everything else. |
… | |
… | |
1028 | callback with the fdatasync result code. |
1097 | callback with the fdatasync result code. |
1029 | |
1098 | |
1030 | If this call isn't available because your OS lacks it or it couldn't be |
1099 | If this call isn't available because your OS lacks it or it couldn't be |
1031 | detected, it will be emulated by calling C<fsync> instead. |
1100 | detected, it will be emulated by calling C<fsync> instead. |
1032 | |
1101 | |
|
|
1102 | =item aio_syncfs $fh, $callback->($status) |
|
|
1103 | |
|
|
1104 | Asynchronously call the syncfs syscall to sync the filesystem associated |
|
|
1105 | to the given filehandle and call the callback with the syncfs result |
|
|
1106 | code. If syncfs is not available, calls sync(), but returns C<-1> and sets |
|
|
1107 | errno to C<ENOSYS> nevertheless. |
|
|
1108 | |
1033 | =item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
1109 | =item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
1034 | |
1110 | |
1035 | Sync the data portion of the file specified by C<$offset> and C<$length> |
1111 | Sync the data portion of the file specified by C<$offset> and C<$length> |
1036 | to disk (but NOT the metadata), by calling the Linux-specific |
1112 | to disk (but NOT the metadata), by calling the Linux-specific |
1037 | sync_file_range call. If sync_file_range is not available or it returns |
1113 | sync_file_range call. If sync_file_range is not available or it returns |
… | |
… | |
1040 | C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>, |
1116 | C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>, |
1041 | C<IO::AIO::SYNC_FILE_RANGE_WRITE> and |
1117 | C<IO::AIO::SYNC_FILE_RANGE_WRITE> and |
1042 | C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range |
1118 | C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range |
1043 | manpage for details. |
1119 | manpage for details. |
1044 | |
1120 | |
1045 | =item aio_pathsync $path, $callback->($status) |
1121 | =item aio_pathsync $pathname, $callback->($status) |
1046 | |
1122 | |
1047 | This request tries to open, fsync and close the given path. This is a |
1123 | This request tries to open, fsync and close the given path. This is a |
1048 | composite request intended to sync directories after directory operations |
1124 | composite request intended to sync directories after directory operations |
1049 | (E.g. rename). This might not work on all operating systems or have any |
1125 | (E.g. rename). This might not work on all operating systems or have any |
1050 | specific effect, but usually it makes sure that directory changes get |
1126 | specific effect, but usually it makes sure that directory changes get |
… | |
… | |
1108 | as for C<aio_msync>, above, except for flags, which must be either |
1184 | as for C<aio_msync>, above, except for flags, which must be either |
1109 | C<0> (which reads all pages and ensures they are instantiated) or |
1185 | C<0> (which reads all pages and ensures they are instantiated) or |
1110 | C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and |
1186 | C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and |
1111 | writing an octet from it, which dirties the page). |
1187 | writing an octet from it, which dirties the page). |
1112 | |
1188 | |
|
|
1189 | =item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
|
|
1190 | |
|
|
1191 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
|
|
1192 | scalars. |
|
|
1193 | |
|
|
1194 | It reads in all the pages of the underlying storage into memory (if any) |
|
|
1195 | and locks them, so they are not getting swapped/paged out or removed. |
|
|
1196 | |
|
|
1197 | If C<$length> is undefined, then the scalar will be locked till the end. |
|
|
1198 | |
|
|
1199 | On systems that do not implement C<mlock>, this function returns C<-1> |
|
|
1200 | and sets errno to C<ENOSYS>. |
|
|
1201 | |
|
|
1202 | Note that the corresponding C<munlock> is synchronous and is |
|
|
1203 | documented under L<MISCELLANEOUS FUNCTIONS>. |
|
|
1204 | |
|
|
1205 | Example: open a file, mmap and mlock it - both will be undone when |
|
|
1206 | C<$data> gets destroyed. |
|
|
1207 | |
|
|
1208 | open my $fh, "<", $path or die "$path: $!"; |
|
|
1209 | my $data; |
|
|
1210 | IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh; |
|
|
1211 | aio_mlock $data; # mlock in background |
|
|
1212 | |
|
|
1213 | =item aio_mlockall $flags, $callback->($status) |
|
|
1214 | |
|
|
1215 | Calls the C<mlockall> function with the given C<$flags> (a combination of |
|
|
1216 | C<IO::AIO::MCL_CURRENT> and C<IO::AIO::MCL_FUTURE>). |
|
|
1217 | |
|
|
1218 | On systems that do not implement C<mlockall>, this function returns C<-1> |
|
|
1219 | and sets errno to C<ENOSYS>. |
|
|
1220 | |
|
|
1221 | Note that the corresponding C<munlockall> is synchronous and is |
|
|
1222 | documented under L<MISCELLANEOUS FUNCTIONS>. |
|
|
1223 | |
|
|
1224 | Example: asynchronously lock all current and future pages into memory. |
|
|
1225 | |
|
|
1226 | aio_mlockall IO::AIO::MCL_FUTURE; |
|
|
1227 | |
1113 | =item aio_group $callback->(...) |
1228 | =item aio_group $callback->(...) |
1114 | |
1229 | |
1115 | This is a very special aio request: Instead of doing something, it is a |
1230 | This is a very special aio request: Instead of doing something, it is a |
1116 | container for other aio requests, which is useful if you want to bundle |
1231 | container for other aio requests, which is useful if you want to bundle |
1117 | many requests into a single, composite, request with a definite callback |
1232 | many requests into a single, composite, request with a definite callback |
… | |
… | |
1153 | like sleep and file handle readable/writable, the overhead this creates is |
1268 | like sleep and file handle readable/writable, the overhead this creates is |
1154 | immense (it blocks a thread for a long time) so do not use this function |
1269 | immense (it blocks a thread for a long time) so do not use this function |
1155 | except to put your application under artificial I/O pressure. |
1270 | except to put your application under artificial I/O pressure. |
1156 | |
1271 | |
1157 | =back |
1272 | =back |
|
|
1273 | |
|
|
1274 | |
|
|
1275 | =head2 IO::AIO::WD - multiple working directories |
|
|
1276 | |
|
|
1277 | Your process only has one current working directory, which is used by all |
|
|
1278 | threads. This makes it hard to use relative paths (some other component |
|
|
1279 | could call C<chdir> at any time, and it is hard to control when the path |
|
|
1280 | will be used by IO::AIO). |
|
|
1281 | |
|
|
1282 | One solution for this is to always use absolute paths. This usually works, |
|
|
1283 | but can be quite slow (the kernel has to walk the whole path on every |
|
|
1284 | access), and can also be a hassle to implement. |
|
|
1285 | |
|
|
1286 | Newer POSIX systems have a number of functions (openat, fdopendir, |
|
|
1287 | futimensat and so on) that make it possible to specify working directories |
|
|
1288 | per operation. |
|
|
1289 | |
|
|
1290 | For portability, and because the clowns who "designed", or shall I write, |
|
|
1291 | perpetrated this new interface were obviously half-drunk, this abstraction |
|
|
1292 | cannot be perfect, though. |
|
|
1293 | |
|
|
1294 | IO::AIO allows you to convert directory paths into a so-called IO::AIO::WD |
|
|
1295 | object. This object stores the canonicalised, absolute version of the |
|
|
1296 | path, and on systems that allow it, also a directory file descriptor. |
|
|
1297 | |
|
|
1298 | Everywhere where a pathname is accepted by IO::AIO (e.g. in C<aio_stat> |
|
|
1299 | or C<aio_unlink>), one can specify an array reference with an IO::AIO::WD |
|
|
1300 | object and a pathname instead. If the pathname is absolute, the |
|
|
1301 | IO::AIO::WD objetc is ignored, otherwise the pathname is resolved relative |
|
|
1302 | to that IO::AIO::WD object. |
|
|
1303 | |
|
|
1304 | For example, to get a wd object for F</etc> and then stat F<passwd> |
|
|
1305 | inside, you would write: |
|
|
1306 | |
|
|
1307 | aio_wd "/etc", sub { |
|
|
1308 | my $etcdir = shift; |
|
|
1309 | |
|
|
1310 | # although $etcdir can be undef on error, there is generally no reason |
|
|
1311 | # to check for errors here, as aio_stat will fail with ENOENT |
|
|
1312 | # when $etcdir is undef. |
|
|
1313 | |
|
|
1314 | aio_stat [$etcdir, "passwd"], sub { |
|
|
1315 | # yay |
|
|
1316 | }; |
|
|
1317 | }; |
|
|
1318 | |
|
|
1319 | This shows that creating an IO::AIO::WD object is itself a potentially |
|
|
1320 | blocking operation, which is why it is done asynchronously. |
|
|
1321 | |
|
|
1322 | As with normal pathnames, IO::AIO keeps a copy of the working directory |
|
|
1323 | object and the pathname string, so you could write the following without |
|
|
1324 | causing any issues due to C<$path> getting reused: |
|
|
1325 | |
|
|
1326 | my $path = [$wd, undef]; |
|
|
1327 | |
|
|
1328 | for my $name (qw(abc def ghi)) { |
|
|
1329 | $path->[1] = $name; |
|
|
1330 | aio_stat $path, sub { |
|
|
1331 | # ... |
|
|
1332 | }; |
|
|
1333 | } |
|
|
1334 | |
|
|
1335 | There are some caveats: when directories get renamed (or deleted), the |
|
|
1336 | pathname string doesn't change, so will point to the new directory (or |
|
|
1337 | nowhere at all), while the directory fd, if available on the system, |
|
|
1338 | will still point to the original directory. Most functions accepting a |
|
|
1339 | pathname will use the directory fd on newer systems, and the string on |
|
|
1340 | older systems. Some functions (such as realpath) will always rely on the |
|
|
1341 | string form of the pathname. |
|
|
1342 | |
|
|
1343 | So this fucntionality is mainly useful to get some protection against |
|
|
1344 | C<chdir>, to easily get an absolute path out of a relative path for future |
|
|
1345 | reference, and to speed up doing many operations in the same directory |
|
|
1346 | (e.g. when stat'ing all files in a directory). |
|
|
1347 | |
|
|
1348 | The following functions implement this working directory abstraction: |
|
|
1349 | |
|
|
1350 | =over 4 |
|
|
1351 | |
|
|
1352 | =item aio_wd $pathname, $callback->($wd) |
|
|
1353 | |
|
|
1354 | Asynchonously canonicalise the given pathname and convert it to an |
|
|
1355 | IO::AIO::WD object representing it. If possible and supported on the |
|
|
1356 | system, also open a directory fd to speed up pathname resolution relative |
|
|
1357 | to this working directory. |
|
|
1358 | |
|
|
1359 | If something goes wrong, then C<undef> is passwd to the callback instead |
|
|
1360 | of a working directory object and C<$!> is set appropriately. Since |
|
|
1361 | passing C<undef> as working directory component of a pathname fails the |
|
|
1362 | request with C<ENOENT>, there is often no need for error checking in the |
|
|
1363 | C<aio_wd> callback, as future requests using the value will fail in the |
|
|
1364 | expected way. |
|
|
1365 | |
|
|
1366 | If this call isn't available because your OS lacks it or it couldn't be |
|
|
1367 | detected, it will be emulated by calling C<fsync> instead. |
|
|
1368 | |
|
|
1369 | =item IO::AIO::CWD |
|
|
1370 | |
|
|
1371 | This is a compiletime constant (object) that represents the process |
|
|
1372 | current working directory. |
|
|
1373 | |
|
|
1374 | Specifying this object as working directory object for a pathname is as |
|
|
1375 | if the pathname would be specified directly, without a directory object, |
|
|
1376 | e.g., these calls are functionally identical: |
|
|
1377 | |
|
|
1378 | aio_stat "somefile", sub { ... }; |
|
|
1379 | aio_stat [IO::AIO::CWD, "somefile"], sub { ... }; |
|
|
1380 | |
|
|
1381 | =back |
|
|
1382 | |
1158 | |
1383 | |
1159 | =head2 IO::AIO::REQ CLASS |
1384 | =head2 IO::AIO::REQ CLASS |
1160 | |
1385 | |
1161 | All non-aggregate C<aio_*> functions return an object of this class when |
1386 | All non-aggregate C<aio_*> functions return an object of this class when |
1162 | called in non-void context. |
1387 | called in non-void context. |
… | |
… | |
1280 | |
1505 | |
1281 | Sets a feeder/generator on this group: every group can have an attached |
1506 | Sets a feeder/generator on this group: every group can have an attached |
1282 | generator that generates requests if idle. The idea behind this is that, |
1507 | generator that generates requests if idle. The idea behind this is that, |
1283 | although you could just queue as many requests as you want in a group, |
1508 | although you could just queue as many requests as you want in a group, |
1284 | this might starve other requests for a potentially long time. For example, |
1509 | this might starve other requests for a potentially long time. For example, |
1285 | C<aio_scandir> might generate hundreds of thousands C<aio_stat> requests, |
1510 | C<aio_scandir> might generate hundreds of thousands of C<aio_stat> |
1286 | delaying any later requests for a long time. |
1511 | requests, delaying any later requests for a long time. |
1287 | |
1512 | |
1288 | To avoid this, and allow incremental generation of requests, you can |
1513 | To avoid this, and allow incremental generation of requests, you can |
1289 | instead a group and set a feeder on it that generates those requests. The |
1514 | instead a group and set a feeder on it that generates those requests. The |
1290 | feed callback will be called whenever there are few enough (see C<limit>, |
1515 | feed callback will be called whenever there are few enough (see C<limit>, |
1291 | below) requests active in the group itself and is expected to queue more |
1516 | below) requests active in the group itself and is expected to queue more |
… | |
… | |
1340 | |
1565 | |
1341 | See C<poll_cb> for an example. |
1566 | See C<poll_cb> for an example. |
1342 | |
1567 | |
1343 | =item IO::AIO::poll_cb |
1568 | =item IO::AIO::poll_cb |
1344 | |
1569 | |
1345 | Process some outstanding events on the result pipe. You have to call this |
1570 | Process some outstanding events on the result pipe. You have to call |
1346 | regularly. Returns C<0> if all events could be processed, or C<-1> if it |
1571 | this regularly. Returns C<0> if all events could be processed (or there |
1347 | returned earlier for whatever reason. Returns immediately when no events |
1572 | were no events to process), or C<-1> if it returned earlier for whatever |
1348 | are outstanding. The amount of events processed depends on the settings of |
1573 | reason. Returns immediately when no events are outstanding. The amount of |
1349 | C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>. |
1574 | events processed depends on the settings of C<IO::AIO::max_poll_req> and |
|
|
1575 | C<IO::AIO::max_poll_time>. |
1350 | |
1576 | |
1351 | If not all requests were processed for whatever reason, the filehandle |
1577 | If not all requests were processed for whatever reason, the filehandle |
1352 | will still be ready when C<poll_cb> returns, so normally you don't have to |
1578 | will still be ready when C<poll_cb> returns, so normally you don't have to |
1353 | do anything special to have it called later. |
1579 | do anything special to have it called later. |
|
|
1580 | |
|
|
1581 | Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes |
|
|
1582 | ready, it can be beneficial to call this function from loops which submit |
|
|
1583 | a lot of requests, to make sure the results get processed when they become |
|
|
1584 | available and not just when the loop is finished and the event loop takes |
|
|
1585 | over again. This function returns very fast when there are no outstanding |
|
|
1586 | requests. |
1354 | |
1587 | |
1355 | Example: Install an Event watcher that automatically calls |
1588 | Example: Install an Event watcher that automatically calls |
1356 | IO::AIO::poll_cb with high priority (more examples can be found in the |
1589 | IO::AIO::poll_cb with high priority (more examples can be found in the |
1357 | SYNOPSIS section, at the top of this document): |
1590 | SYNOPSIS section, at the top of this document): |
1358 | |
1591 | |
… | |
… | |
1460 | |
1693 | |
1461 | Under normal circumstances you don't need to call this function. |
1694 | Under normal circumstances you don't need to call this function. |
1462 | |
1695 | |
1463 | =item IO::AIO::max_idle $nthreads |
1696 | =item IO::AIO::max_idle $nthreads |
1464 | |
1697 | |
1465 | Limit the number of threads (default: 4) that are allowed to idle (i.e., |
1698 | Limit the number of threads (default: 4) that are allowed to idle |
1466 | threads that did not get a request to process within 10 seconds). That |
1699 | (i.e., threads that did not get a request to process within the idle |
1467 | means if a thread becomes idle while C<$nthreads> other threads are also |
1700 | timeout (default: 10 seconds). That means if a thread becomes idle while |
1468 | idle, it will free its resources and exit. |
1701 | C<$nthreads> other threads are also idle, it will free its resources and |
|
|
1702 | exit. |
1469 | |
1703 | |
1470 | This is useful when you allow a large number of threads (e.g. 100 or 1000) |
1704 | This is useful when you allow a large number of threads (e.g. 100 or 1000) |
1471 | to allow for extremely high load situations, but want to free resources |
1705 | to allow for extremely high load situations, but want to free resources |
1472 | under normal circumstances (1000 threads can easily consume 30MB of RAM). |
1706 | under normal circumstances (1000 threads can easily consume 30MB of RAM). |
1473 | |
1707 | |
1474 | The default is probably ok in most situations, especially if thread |
1708 | The default is probably ok in most situations, especially if thread |
1475 | creation is fast. If thread creation is very slow on your system you might |
1709 | creation is fast. If thread creation is very slow on your system you might |
1476 | want to use larger values. |
1710 | want to use larger values. |
1477 | |
1711 | |
|
|
1712 | =item IO::AIO::idle_timeout $seconds |
|
|
1713 | |
|
|
1714 | Sets the minimum idle timeout (default 10) after which worker threads are |
|
|
1715 | allowed to exit. SEe C<IO::AIO::max_idle>. |
|
|
1716 | |
1478 | =item IO::AIO::max_outstanding $maxreqs |
1717 | =item IO::AIO::max_outstanding $maxreqs |
|
|
1718 | |
|
|
1719 | Sets the maximum number of outstanding requests to C<$nreqs>. If |
|
|
1720 | you do queue up more than this number of requests, the next call to |
|
|
1721 | C<IO::AIO::poll_cb> (and other functions calling C<poll_cb>, such as |
|
|
1722 | C<IO::AIO::flush> or C<IO::AIO::poll>) will block until the limit is no |
|
|
1723 | longer exceeded. |
|
|
1724 | |
|
|
1725 | In other words, this setting does not enforce a queue limit, but can be |
|
|
1726 | used to make poll functions block if the limit is exceeded. |
1479 | |
1727 | |
1480 | This is a very bad function to use in interactive programs because it |
1728 | This is a very bad function to use in interactive programs because it |
1481 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
1729 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
1482 | use an C<aio_group> together with a feed callback. |
1730 | use an C<aio_group> together with a feed callback. |
1483 | |
1731 | |
1484 | Sets the maximum number of outstanding requests to C<$nreqs>. If you |
1732 | It's main use is in scripts without an event loop - when you want to stat |
1485 | do queue up more than this number of requests, the next call to the |
1733 | a lot of files, you can write somehting like this: |
1486 | C<poll_cb> (and C<poll_some> and other functions calling C<poll_cb>) |
|
|
1487 | function will block until the limit is no longer exceeded. |
|
|
1488 | |
1734 | |
1489 | The default value is very large, so there is no practical limit on the |
1735 | IO::AIO::max_outstanding 32; |
1490 | number of outstanding requests. |
|
|
1491 | |
1736 | |
1492 | You can still queue as many requests as you want. Therefore, |
1737 | for my $path (...) { |
1493 | C<max_outstanding> is mainly useful in simple scripts (with low values) or |
1738 | aio_stat $path , ...; |
1494 | as a stop gap to shield against fatal memory overflow (with large values). |
1739 | IO::AIO::poll_cb; |
|
|
1740 | } |
|
|
1741 | |
|
|
1742 | IO::AIO::flush; |
|
|
1743 | |
|
|
1744 | The call to C<poll_cb> inside the loop will normally return instantly, but |
|
|
1745 | as soon as more thna C<32> reqeusts are in-flight, it will block until |
|
|
1746 | some requests have been handled. This keeps the loop from pushing a large |
|
|
1747 | number of C<aio_stat> requests onto the queue. |
|
|
1748 | |
|
|
1749 | The default value for C<max_outstanding> is very large, so there is no |
|
|
1750 | practical limit on the number of outstanding requests. |
1495 | |
1751 | |
1496 | =back |
1752 | =back |
1497 | |
1753 | |
1498 | =head3 STATISTICAL INFORMATION |
1754 | =head3 STATISTICAL INFORMATION |
1499 | |
1755 | |
… | |
… | |
1537 | |
1793 | |
1538 | Returns the number of bytes copied, or C<-1> on error. |
1794 | Returns the number of bytes copied, or C<-1> on error. |
1539 | |
1795 | |
1540 | =item IO::AIO::fadvise $fh, $offset, $len, $advice |
1796 | =item IO::AIO::fadvise $fh, $offset, $len, $advice |
1541 | |
1797 | |
1542 | Simply calls the C<posix_fadvise> function (see it's |
1798 | Simply calls the C<posix_fadvise> function (see its |
1543 | manpage for details). The following advice constants are |
1799 | manpage for details). The following advice constants are |
1544 | avaiable: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>, |
1800 | available: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>, |
1545 | C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>, |
1801 | C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>, |
1546 | C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>. |
1802 | C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>. |
1547 | |
1803 | |
1548 | On systems that do not implement C<posix_fadvise>, this function returns |
1804 | On systems that do not implement C<posix_fadvise>, this function returns |
1549 | ENOSYS, otherwise the return value of C<posix_fadvise>. |
1805 | ENOSYS, otherwise the return value of C<posix_fadvise>. |
|
|
1806 | |
|
|
1807 | =item IO::AIO::madvise $scalar, $offset, $len, $advice |
|
|
1808 | |
|
|
1809 | Simply calls the C<posix_madvise> function (see its |
|
|
1810 | manpage for details). The following advice constants are |
|
|
1811 | available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>, |
|
|
1812 | C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>. |
|
|
1813 | |
|
|
1814 | On systems that do not implement C<posix_madvise>, this function returns |
|
|
1815 | ENOSYS, otherwise the return value of C<posix_madvise>. |
|
|
1816 | |
|
|
1817 | =item IO::AIO::mprotect $scalar, $offset, $len, $protect |
|
|
1818 | |
|
|
1819 | Simply calls the C<mprotect> function on the preferably AIO::mmap'ed |
|
|
1820 | $scalar (see its manpage for details). The following protect |
|
|
1821 | constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>, |
|
|
1822 | C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>. |
|
|
1823 | |
|
|
1824 | On systems that do not implement C<mprotect>, this function returns |
|
|
1825 | ENOSYS, otherwise the return value of C<mprotect>. |
1550 | |
1826 | |
1551 | =item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
1827 | =item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
1552 | |
1828 | |
1553 | Memory-maps a file (or anonymous memory range) and attaches it to the |
1829 | Memory-maps a file (or anonymous memory range) and attaches it to the |
1554 | given C<$scalar>, which will act like a string scalar. |
1830 | given C<$scalar>, which will act like a string scalar. |
… | |
… | |
1580 | C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or |
1856 | C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or |
1581 | C<IO::AIO::MAP_NONBLOCK> |
1857 | C<IO::AIO::MAP_NONBLOCK> |
1582 | |
1858 | |
1583 | If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed. |
1859 | If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed. |
1584 | |
1860 | |
|
|
1861 | C<$offset> is the offset from the start of the file - it generally must be |
|
|
1862 | a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>. |
|
|
1863 | |
1585 | Example: |
1864 | Example: |
1586 | |
1865 | |
1587 | use Digest::MD5; |
1866 | use Digest::MD5; |
1588 | use IO::AIO; |
1867 | use IO::AIO; |
1589 | |
1868 | |
… | |
… | |
1597 | |
1876 | |
1598 | =item IO::AIO::munmap $scalar |
1877 | =item IO::AIO::munmap $scalar |
1599 | |
1878 | |
1600 | Removes a previous mmap and undefines the C<$scalar>. |
1879 | Removes a previous mmap and undefines the C<$scalar>. |
1601 | |
1880 | |
1602 | =item IO::AIO::mlockall $flags |
1881 | =item IO::AIO::munlock $scalar, $offset = 0, $length = undef |
1603 | |
1882 | |
1604 | Calls the C<mlockall> function with the given C<$flags> (a combination of |
1883 | Calls the C<munlock> function, undoing the effects of a previous |
1605 | C<IO::AIO::MCL_CURRENT> and C<IO::AIO::MCL__FUTURE>). |
1884 | C<aio_mlock> call (see its description for details). |
1606 | |
|
|
1607 | On systems that do not implement C<mlockall>, this function returns |
|
|
1608 | ENOSYS, otherwise the return value of C<mlockall>. |
|
|
1609 | |
1885 | |
1610 | =item IO::AIO::munlockall |
1886 | =item IO::AIO::munlockall |
1611 | |
1887 | |
1612 | Calls the C<munlockall> function. |
1888 | Calls the C<munlockall> function. |
1613 | |
1889 | |
… | |
… | |
1655 | Danga::Socket->AddOtherFds (IO::AIO::poll_fileno => |
1931 | Danga::Socket->AddOtherFds (IO::AIO::poll_fileno => |
1656 | \&IO::AIO::poll_cb); |
1932 | \&IO::AIO::poll_cb); |
1657 | |
1933 | |
1658 | =head2 FORK BEHAVIOUR |
1934 | =head2 FORK BEHAVIOUR |
1659 | |
1935 | |
1660 | This module should do "the right thing" when the process using it forks: |
1936 | Usage of pthreads in a program changes the semantics of fork |
|
|
1937 | considerably. Specifically, only async-safe functions can be called after |
|
|
1938 | fork. Perl doesn't know about this, so in general, you cannot call fork |
|
|
1939 | with defined behaviour in perl if pthreads are involved. IO::AIO uses |
|
|
1940 | pthreads, so this applies, but many other extensions and (for inexplicable |
|
|
1941 | reasons) perl itself often is linked against pthreads, so this limitation |
|
|
1942 | applies to quite a lot of perls. |
1661 | |
1943 | |
1662 | Before the fork, IO::AIO enters a quiescent state where no requests |
1944 | This module no longer tries to fight your OS, or POSIX. That means IO::AIO |
1663 | can be added in other threads and no results will be processed. After |
1945 | only works in the process that loaded it. Forking is fully supported, but |
1664 | the fork the parent simply leaves the quiescent state and continues |
1946 | using IO::AIO in the child is not. |
1665 | request/result processing, while the child frees the request/result queue |
|
|
1666 | (so that the requests started before the fork will only be handled in the |
|
|
1667 | parent). Threads will be started on demand until the limit set in the |
|
|
1668 | parent process has been reached again. |
|
|
1669 | |
1947 | |
1670 | In short: the parent will, after a short pause, continue as if fork had |
1948 | You might get around by not I<using> IO::AIO before (or after) |
1671 | not been called, while the child will act as if IO::AIO has not been used |
1949 | forking. You could also try to call the L<IO::AIO::reinit> function in the |
1672 | yet. |
1950 | child: |
|
|
1951 | |
|
|
1952 | =over 4 |
|
|
1953 | |
|
|
1954 | =item IO::AIO::reinit |
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1955 | |
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1956 | Abandons all current requests and I/O threads and simply reinitialises all |
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1957 | data structures. This is not an operation supported by any standards, but |
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1958 | happens to work on GNU/Linux and some newer BSD systems. |
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1959 | |
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1960 | The only reasonable use for this function is to call it after forking, if |
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1961 | C<IO::AIO> was used in the parent. Calling it while IO::AIO is active in |
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1962 | the process will result in undefined behaviour. Calling it at any time |
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1963 | will also result in any undefined (by POSIX) behaviour. |
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1964 | |
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1965 | =back |
1673 | |
1966 | |
1674 | =head2 MEMORY USAGE |
1967 | =head2 MEMORY USAGE |
1675 | |
1968 | |
1676 | Per-request usage: |
1969 | Per-request usage: |
1677 | |
1970 | |