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 | |
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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; |
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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. |
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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 = '4.11'; |
176 | our $VERSION = 4.4; |
174 | |
177 | |
175 | our @AIO_REQ = qw(aio_sendfile 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 |
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 |
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202 | |
206 | |
203 | =head1 FUNCTIONS |
207 | =head1 FUNCTIONS |
204 | |
208 | |
205 | =head2 QUICK OVERVIEW |
209 | =head2 QUICK OVERVIEW |
206 | |
210 | |
207 | This section simply lists the prototypes of the most important functions |
211 | This section simply lists the prototypes most of the functions for |
208 | for quick reference. See the following sections for function-by-function |
212 | quick reference. See the following sections for function-by-function |
209 | documentation. |
213 | documentation. |
210 | |
214 | |
211 | aio_wd $pathname, $callback->($wd) |
215 | aio_wd $pathname, $callback->($wd) |
212 | aio_open $pathname, $flags, $mode, $callback->($fh) |
216 | aio_open $pathname, $flags, $mode, $callback->($fh) |
213 | aio_close $fh, $callback->($status) |
217 | aio_close $fh, $callback->($status) |
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218 | aio_seek $fh,$offset,$whence, $callback->($offs) |
214 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
219 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
215 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
220 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
216 | aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval) |
221 | aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval) |
217 | aio_readahead $fh,$offset,$length, $callback->($retval) |
222 | aio_readahead $fh,$offset,$length, $callback->($retval) |
218 | aio_stat $fh_or_path, $callback->($status) |
223 | aio_stat $fh_or_path, $callback->($status) |
219 | aio_lstat $fh, $callback->($status) |
224 | aio_lstat $fh, $callback->($status) |
220 | aio_statvfs $fh_or_path, $callback->($statvfs) |
225 | aio_statvfs $fh_or_path, $callback->($statvfs) |
221 | aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
226 | aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
222 | aio_chown $fh_or_path, $uid, $gid, $callback->($status) |
227 | aio_chown $fh_or_path, $uid, $gid, $callback->($status) |
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228 | aio_chmod $fh_or_path, $mode, $callback->($status) |
223 | aio_truncate $fh_or_path, $offset, $callback->($status) |
229 | aio_truncate $fh_or_path, $offset, $callback->($status) |
224 | aio_chmod $fh_or_path, $mode, $callback->($status) |
230 | aio_allocate $fh, $mode, $offset, $len, $callback->($status) |
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231 | aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents) |
225 | aio_unlink $pathname, $callback->($status) |
232 | aio_unlink $pathname, $callback->($status) |
226 | aio_mknod $pathname, $mode, $dev, $callback->($status) |
233 | aio_mknod $pathname, $mode, $dev, $callback->($status) |
227 | aio_link $srcpath, $dstpath, $callback->($status) |
234 | aio_link $srcpath, $dstpath, $callback->($status) |
228 | aio_symlink $srcpath, $dstpath, $callback->($status) |
235 | aio_symlink $srcpath, $dstpath, $callback->($status) |
229 | aio_readlink $pathname, $callback->($link) |
236 | aio_readlink $pathname, $callback->($link) |
230 | aio_realpath $pathname, $callback->($link) |
237 | aio_realpath $pathname, $callback->($path) |
231 | 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) |
232 | aio_mkdir $pathname, $mode, $callback->($status) |
240 | aio_mkdir $pathname, $mode, $callback->($status) |
233 | aio_rmdir $pathname, $callback->($status) |
241 | aio_rmdir $pathname, $callback->($status) |
234 | aio_readdir $pathname, $callback->($entries) |
242 | aio_readdir $pathname, $callback->($entries) |
235 | aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
243 | aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
236 | IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST |
244 | IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST |
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238 | aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs) |
246 | aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs) |
239 | aio_load $pathname, $data, $callback->($status) |
247 | aio_load $pathname, $data, $callback->($status) |
240 | aio_copy $srcpath, $dstpath, $callback->($status) |
248 | aio_copy $srcpath, $dstpath, $callback->($status) |
241 | aio_move $srcpath, $dstpath, $callback->($status) |
249 | aio_move $srcpath, $dstpath, $callback->($status) |
242 | 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) |
243 | aio_sync $callback->($status) |
253 | aio_sync $callback->($status) |
244 | aio_syncfs $fh, $callback->($status) |
254 | aio_syncfs $fh, $callback->($status) |
245 | aio_fsync $fh, $callback->($status) |
255 | aio_fsync $fh, $callback->($status) |
246 | aio_fdatasync $fh, $callback->($status) |
256 | aio_fdatasync $fh, $callback->($status) |
247 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
257 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
248 | aio_pathsync $pathname, $callback->($status) |
258 | aio_pathsync $pathname, $callback->($status) |
249 | aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
259 | aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status) |
250 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
260 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
251 | aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
261 | aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
252 | aio_mlockall $flags, $callback->($status) |
262 | aio_mlockall $flags, $callback->($status) |
253 | aio_group $callback->(...) |
263 | aio_group $callback->(...) |
254 | aio_nop $callback->() |
264 | aio_nop $callback->() |
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268 | IO::AIO::idle_timeout $seconds |
278 | IO::AIO::idle_timeout $seconds |
269 | IO::AIO::max_outstanding $maxreqs |
279 | IO::AIO::max_outstanding $maxreqs |
270 | IO::AIO::nreqs |
280 | IO::AIO::nreqs |
271 | IO::AIO::nready |
281 | IO::AIO::nready |
272 | 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] |
273 | |
285 | |
274 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
286 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
275 | IO::AIO::fadvise $fh, $offset, $len, $advice |
287 | IO::AIO::fadvise $fh, $offset, $len, $advice |
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288 | IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]] |
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289 | IO::AIO::munmap $scalar |
276 | IO::AIO::madvise $scalar, $offset, $length, $advice |
290 | IO::AIO::madvise $scalar, $offset, $length, $advice |
277 | IO::AIO::mprotect $scalar, $offset, $length, $protect |
291 | IO::AIO::mprotect $scalar, $offset, $length, $protect |
278 | IO::AIO::munlock $scalar, $offset = 0, $length = undef |
292 | IO::AIO::munlock $scalar, $offset = 0, $length = undef |
279 | IO::AIO::munlockall |
293 | IO::AIO::munlockall |
280 | |
294 | |
281 | =head2 AIO REQUEST FUNCTIONS |
295 | =head2 API NOTES |
282 | |
296 | |
283 | All the C<aio_*> calls are more or less thin wrappers around the syscall |
297 | All the C<aio_*> calls are more or less thin wrappers around the syscall |
284 | with the same name (sans C<aio_>). The arguments are similar or identical, |
298 | with the same name (sans C<aio_>). The arguments are similar or identical, |
285 | and they all accept an additional (and optional) C<$callback> argument |
299 | and they all accept an additional (and optional) C<$callback> argument |
286 | which must be a code reference. This code reference will be called after |
300 | which must be a code reference. This code reference will be called after |
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317 | correct contents. |
331 | correct contents. |
318 | |
332 | |
319 | This works, btw. independent of the internal UTF-8 bit, which IO::AIO |
333 | This works, btw. independent of the internal UTF-8 bit, which IO::AIO |
320 | handles correctly whether it is set or not. |
334 | handles correctly whether it is set or not. |
321 | |
335 | |
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336 | =head2 AIO REQUEST FUNCTIONS |
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337 | |
322 | =over 4 |
338 | =over 4 |
323 | |
339 | |
324 | =item $prev_pri = aioreq_pri [$pri] |
340 | =item $prev_pri = aioreq_pri [$pri] |
325 | |
341 | |
326 | Returns the priority value that would be used for the next request and, if |
342 | Returns the priority value that would be used for the next request and, if |
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355 | |
371 | |
356 | |
372 | |
357 | =item aio_open $pathname, $flags, $mode, $callback->($fh) |
373 | =item aio_open $pathname, $flags, $mode, $callback->($fh) |
358 | |
374 | |
359 | 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 |
360 | created filehandle for the file. |
376 | created filehandle for the file (or C<undef> in case of an error). |
361 | |
377 | |
362 | 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, |
363 | for an explanation. |
379 | for an explanation. |
364 | |
380 | |
365 | 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 |
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388 | following POSIX and non-POSIX constants are available (missing ones on |
404 | following POSIX and non-POSIX constants are available (missing ones on |
389 | your system are, as usual, C<0>): |
405 | your system are, as usual, C<0>): |
390 | |
406 | |
391 | 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>, |
392 | 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>, |
393 | 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>. |
394 | |
410 | |
395 | |
411 | |
396 | =item aio_close $fh, $callback->($status) |
412 | =item aio_close $fh, $callback->($status) |
397 | |
413 | |
398 | Asynchronously close a file and call the callback with the result |
414 | Asynchronously close a file and call the callback with the result |
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408 | Or in other words: the file descriptor will be closed, but it will not be |
424 | Or in other words: the file descriptor will be closed, but it will not be |
409 | free for reuse until the perl filehandle is closed. |
425 | free for reuse until the perl filehandle is closed. |
410 | |
426 | |
411 | =cut |
427 | =cut |
412 | |
428 | |
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429 | =item aio_seek $fh, $offset, $whence, $callback->($offs) |
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430 | |
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431 | Seeks the filehandle to the new C<$offset>, similarly to perl's |
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432 | C<sysseek>. The C<$whence> can use the traditional values (C<0> for |
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433 | C<IO::AIO::SEEK_SET>, C<1> for C<IO::AIO::SEEK_CUR> or C<2> for |
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434 | C<IO::AIO::SEEK_END>). |
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435 | |
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436 | The resulting absolute offset will be passed to the callback, or C<-1> in |
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437 | case of an error. |
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438 | |
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439 | In theory, the C<$whence> constants could be different than the |
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440 | corresponding values from L<Fcntl>, but perl guarantees they are the same, |
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441 | so don't panic. |
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442 | |
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443 | As a GNU/Linux (and maybe Solaris) extension, also the constants |
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444 | C<IO::AIO::SEEK_DATA> and C<IO::AIO::SEEK_HOLE> are available, if they |
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445 | could be found. No guarantees about suitability for use in C<aio_seek> or |
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446 | Perl's C<sysseek> can be made though, although I would naively assume they |
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447 | "just work". |
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448 | |
413 | =item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
449 | =item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
414 | |
450 | |
415 | =item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
451 | =item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
416 | |
452 | |
417 | 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 |
418 | 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 |
419 | 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 |
420 | error, just like the syscall). |
456 | error, just like the syscall). |
421 | |
457 | |
422 | 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 |
423 | offset plus the actual number of bytes read. |
459 | offset plus the actual number of bytes read. |
424 | |
460 | |
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482 | As native sendfile syscalls (as practically any non-POSIX interface hacked |
518 | As native sendfile syscalls (as practically any non-POSIX interface hacked |
483 | 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 |
484 | 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 |
485 | 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, |
486 | 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> - |
487 | fewre bytes than expected might have been transferred. |
523 | fewer bytes than expected might have been transferred. |
488 | |
524 | |
489 | |
525 | |
490 | =item aio_readahead $fh,$offset,$length, $callback->($retval) |
526 | =item aio_readahead $fh,$offset,$length, $callback->($retval) |
491 | |
527 | |
492 | 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 |
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496 | 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 |
497 | 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 |
498 | (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 |
499 | file. The current file offset of the file is left unchanged. |
535 | file. The current file offset of the file is left unchanged. |
500 | |
536 | |
501 | 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 |
502 | 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. |
503 | |
539 | |
504 | |
540 | |
505 | =item aio_stat $fh_or_path, $callback->($status) |
541 | =item aio_stat $fh_or_path, $callback->($status) |
506 | |
542 | |
507 | =item aio_lstat $fh, $callback->($status) |
543 | =item aio_lstat $fh, $callback->($status) |
… | |
… | |
576 | namemax => 255, |
612 | namemax => 255, |
577 | frsize => 1024, |
613 | frsize => 1024, |
578 | fsid => 1810 |
614 | fsid => 1810 |
579 | } |
615 | } |
580 | |
616 | |
581 | |
|
|
582 | =item aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
617 | =item aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
583 | |
618 | |
584 | Works like perl's C<utime> function (including the special case of $atime |
619 | Works like perl's C<utime> function (including the special case of $atime |
585 | and $mtime being undef). Fractional times are supported if the underlying |
620 | and $mtime being undef). Fractional times are supported if the underlying |
586 | syscalls support them. |
621 | syscalls support them. |
… | |
… | |
613 | =item aio_truncate $fh_or_path, $offset, $callback->($status) |
648 | =item aio_truncate $fh_or_path, $offset, $callback->($status) |
614 | |
649 | |
615 | Works like truncate(2) or ftruncate(2). |
650 | Works like truncate(2) or ftruncate(2). |
616 | |
651 | |
617 | |
652 | |
|
|
653 | =item aio_allocate $fh, $mode, $offset, $len, $callback->($status) |
|
|
654 | |
|
|
655 | Allocates or frees disk space according to the C<$mode> argument. See the |
|
|
656 | linux C<fallocate> documentation for details. |
|
|
657 | |
|
|
658 | C<$mode> is usually C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> to allocate |
|
|
659 | space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE | IO::AIO::FALLOC_FL_KEEP_SIZE>, |
|
|
660 | to deallocate a file range. |
|
|
661 | |
|
|
662 | IO::AIO also supports C<FALLOC_FL_COLLAPSE_RANGE>, to remove a range |
|
|
663 | (without leaving a hole), C<FALLOC_FL_ZERO_RANGE>, to zero a range, |
|
|
664 | C<FALLOC_FL_INSERT_RANGE> to insert a range and C<FALLOC_FL_UNSHARE_RANGE> |
|
|
665 | to unshare shared blocks (see your L<fallocate(2)> manpage). |
|
|
666 | |
|
|
667 | The file system block size used by C<fallocate> is presumably the |
|
|
668 | C<f_bsize> returned by C<statvfs>, but different filesystems and filetypes |
|
|
669 | can dictate other limitations. |
|
|
670 | |
|
|
671 | If C<fallocate> isn't available or cannot be emulated (currently no |
|
|
672 | emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>. |
|
|
673 | |
|
|
674 | |
618 | =item aio_chmod $fh_or_path, $mode, $callback->($status) |
675 | =item aio_chmod $fh_or_path, $mode, $callback->($status) |
619 | |
676 | |
620 | Works like perl's C<chmod> function. |
677 | Works like perl's C<chmod> function. |
621 | |
678 | |
622 | |
679 | |
… | |
… | |
659 | |
716 | |
660 | |
717 | |
661 | =item aio_realpath $pathname, $callback->($path) |
718 | =item aio_realpath $pathname, $callback->($path) |
662 | |
719 | |
663 | Asynchronously make the path absolute and resolve any symlinks in |
720 | Asynchronously make the path absolute and resolve any symlinks in |
664 | C<$path>. The resulting path only consists of directories (Same as |
721 | C<$path>. The resulting path only consists of directories (same as |
665 | L<Cwd::realpath>). |
722 | L<Cwd::realpath>). |
666 | |
723 | |
667 | This request can be used to get the absolute path of the current working |
724 | This request can be used to get the absolute path of the current working |
668 | directory by passing it a path of F<.> (a single dot). |
725 | directory by passing it a path of F<.> (a single dot). |
669 | |
726 | |
670 | |
727 | |
671 | =item aio_rename $srcpath, $dstpath, $callback->($status) |
728 | =item aio_rename $srcpath, $dstpath, $callback->($status) |
672 | |
729 | |
673 | Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as |
730 | Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as |
674 | rename(2) and call the callback with the result code. |
731 | rename(2) and call the callback with the result code. |
|
|
732 | |
|
|
733 | On systems that support the AIO::WD working directory abstraction |
|
|
734 | natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead |
|
|
735 | of failing, C<rename> is called on the absolute path of C<$wd>. |
|
|
736 | |
|
|
737 | |
|
|
738 | =item aio_rename2 $srcpath, $dstpath, $flags, $callback->($status) |
|
|
739 | |
|
|
740 | Basically a version of C<aio_rename> with an additional C<$flags> |
|
|
741 | argument. Calling this with C<$flags=0> is the same as calling |
|
|
742 | C<aio_rename>. |
|
|
743 | |
|
|
744 | Non-zero flags are currently only supported on GNU/Linux systems that |
|
|
745 | support renameat2. Other systems fail with C<ENOSYS> in this case. |
|
|
746 | |
|
|
747 | The following constants are available (missing ones are, as usual C<0>), |
|
|
748 | see renameat2(2) for details: |
|
|
749 | |
|
|
750 | C<IO::AIO::RENAME_NOREPLACE>, C<IO::AIO::RENAME_EXCHANGE> |
|
|
751 | and C<IO::AIO::RENAME_WHITEOUT>. |
675 | |
752 | |
676 | |
753 | |
677 | =item aio_mkdir $pathname, $mode, $callback->($status) |
754 | =item aio_mkdir $pathname, $mode, $callback->($status) |
678 | |
755 | |
679 | Asynchronously mkdir (create) a directory and call the callback with |
756 | Asynchronously mkdir (create) a directory and call the callback with |
… | |
… | |
684 | =item aio_rmdir $pathname, $callback->($status) |
761 | =item aio_rmdir $pathname, $callback->($status) |
685 | |
762 | |
686 | Asynchronously rmdir (delete) a directory and call the callback with the |
763 | Asynchronously rmdir (delete) a directory and call the callback with the |
687 | result code. |
764 | result code. |
688 | |
765 | |
|
|
766 | On systems that support the AIO::WD working directory abstraction |
|
|
767 | natively, the case C<[$wd, "."]> is specialcased - instead of failing, |
|
|
768 | C<rmdir> is called on the absolute path of C<$wd>. |
|
|
769 | |
689 | |
770 | |
690 | =item aio_readdir $pathname, $callback->($entries) |
771 | =item aio_readdir $pathname, $callback->($entries) |
691 | |
772 | |
692 | Unlike the POSIX call of the same name, C<aio_readdir> reads an entire |
773 | Unlike the POSIX call of the same name, C<aio_readdir> reads an entire |
693 | directory (i.e. opendir + readdir + closedir). The entries will not be |
774 | directory (i.e. opendir + readdir + closedir). The entries will not be |
… | |
… | |
708 | |
789 | |
709 | =over 4 |
790 | =over 4 |
710 | |
791 | |
711 | =item IO::AIO::READDIR_DENTS |
792 | =item IO::AIO::READDIR_DENTS |
712 | |
793 | |
713 | When this flag is off, then the callback gets an arrayref consisting of |
794 | Normally the callback gets an arrayref consisting of names only (as |
714 | names only (as with C<aio_readdir>), otherwise it gets an arrayref with |
795 | with C<aio_readdir>). If this flag is set, then the callback gets an |
715 | C<[$name, $type, $inode]> arrayrefs, each describing a single directory |
796 | arrayref with C<[$name, $type, $inode]> arrayrefs, each describing a |
716 | entry in more detail. |
797 | single directory entry in more detail: |
717 | |
798 | |
718 | C<$name> is the name of the entry. |
799 | C<$name> is the name of the entry. |
719 | |
800 | |
720 | C<$type> is one of the C<IO::AIO::DT_xxx> constants: |
801 | C<$type> is one of the C<IO::AIO::DT_xxx> constants: |
721 | |
802 | |
722 | C<IO::AIO::DT_UNKNOWN>, C<IO::AIO::DT_FIFO>, C<IO::AIO::DT_CHR>, C<IO::AIO::DT_DIR>, |
803 | C<IO::AIO::DT_UNKNOWN>, C<IO::AIO::DT_FIFO>, C<IO::AIO::DT_CHR>, C<IO::AIO::DT_DIR>, |
723 | C<IO::AIO::DT_BLK>, C<IO::AIO::DT_REG>, C<IO::AIO::DT_LNK>, C<IO::AIO::DT_SOCK>, |
804 | C<IO::AIO::DT_BLK>, C<IO::AIO::DT_REG>, C<IO::AIO::DT_LNK>, C<IO::AIO::DT_SOCK>, |
724 | C<IO::AIO::DT_WHT>. |
805 | C<IO::AIO::DT_WHT>. |
725 | |
806 | |
726 | C<IO::AIO::DT_UNKNOWN> means just that: readdir does not know. If you need to |
807 | C<IO::AIO::DT_UNKNOWN> means just that: readdir does not know. If you need |
727 | know, you have to run stat yourself. Also, for speed reasons, the C<$type> |
808 | to know, you have to run stat yourself. Also, for speed/memory reasons, |
728 | scalars are read-only: you can not modify them. |
809 | the C<$type> scalars are read-only: you must not modify them. |
729 | |
810 | |
730 | C<$inode> is the inode number (which might not be exact on systems with 64 |
811 | C<$inode> is the inode number (which might not be exact on systems with 64 |
731 | bit inode numbers and 32 bit perls). This field has unspecified content on |
812 | bit inode numbers and 32 bit perls). This field has unspecified content on |
732 | systems that do not deliver the inode information. |
813 | systems that do not deliver the inode information. |
733 | |
814 | |
… | |
… | |
744 | short names are tried first. |
825 | short names are tried first. |
745 | |
826 | |
746 | =item IO::AIO::READDIR_STAT_ORDER |
827 | =item IO::AIO::READDIR_STAT_ORDER |
747 | |
828 | |
748 | When this flag is set, then the names will be returned in an order |
829 | When this flag is set, then the names will be returned in an order |
749 | suitable for stat()'ing each one. That is, when you plan to stat() |
830 | suitable for stat()'ing each one. That is, when you plan to stat() most or |
750 | all files in the given directory, then the returned order will likely |
831 | all files in the given directory, then the returned order will likely be |
751 | be fastest. |
832 | faster. |
752 | |
833 | |
753 | If both this flag and C<IO::AIO::READDIR_DIRS_FIRST> are specified, then |
834 | If both this flag and C<IO::AIO::READDIR_DIRS_FIRST> are specified, |
754 | the likely dirs come first, resulting in a less optimal stat order. |
835 | then the likely dirs come first, resulting in a less optimal stat order |
|
|
836 | for stat'ing all entries, but likely a more optimal order for finding |
|
|
837 | subdirectories. |
755 | |
838 | |
756 | =item IO::AIO::READDIR_FOUND_UNKNOWN |
839 | =item IO::AIO::READDIR_FOUND_UNKNOWN |
757 | |
840 | |
758 | This flag should not be set when calling C<aio_readdirx>. Instead, it |
841 | This flag should not be set when calling C<aio_readdirx>. Instead, it |
759 | is being set by C<aio_readdirx>, when any of the C<$type>'s found were |
842 | is being set by C<aio_readdirx>, when any of the C<$type>'s found were |
… | |
… | |
761 | C<$type>'s are known, which can be used to speed up some algorithms. |
844 | C<$type>'s are known, which can be used to speed up some algorithms. |
762 | |
845 | |
763 | =back |
846 | =back |
764 | |
847 | |
765 | |
848 | |
|
|
849 | =item aio_slurp $pathname, $offset, $length, $data, $callback->($status) |
|
|
850 | |
|
|
851 | Opens, reads and closes the given file. The data is put into C<$data>, |
|
|
852 | which is resized as required. |
|
|
853 | |
|
|
854 | If C<$offset> is negative, then it is counted from the end of the file. |
|
|
855 | |
|
|
856 | If C<$length> is zero, then the remaining length of the file is |
|
|
857 | used. Also, in this case, the same limitations to modifying C<$data> apply |
|
|
858 | as when IO::AIO::mmap is used, i.e. it must only be modified in-place |
|
|
859 | with C<substr>. If the size of the file is known, specifying a non-zero |
|
|
860 | C<$length> results in a performance advantage. |
|
|
861 | |
|
|
862 | This request is similar to the older C<aio_load> request, but since it is |
|
|
863 | a single request, it might be more efficient to use. |
|
|
864 | |
|
|
865 | Example: load F</etc/passwd> into C<$passwd>. |
|
|
866 | |
|
|
867 | my $passwd; |
|
|
868 | aio_slurp "/etc/passwd", 0, 0, $passwd, sub { |
|
|
869 | $_[0] >= 0 |
|
|
870 | or die "/etc/passwd: $!\n"; |
|
|
871 | |
|
|
872 | printf "/etc/passwd is %d bytes long, and contains:\n", length $passwd; |
|
|
873 | print $passwd; |
|
|
874 | }; |
|
|
875 | IO::AIO::flush; |
|
|
876 | |
|
|
877 | |
766 | =item aio_load $pathname, $data, $callback->($status) |
878 | =item aio_load $pathname, $data, $callback->($status) |
767 | |
879 | |
768 | This is a composite request that tries to fully load the given file into |
880 | This is a composite request that tries to fully load the given file into |
769 | memory. Status is the same as with aio_read. |
881 | memory. Status is the same as with aio_read. |
|
|
882 | |
|
|
883 | Using C<aio_slurp> might be more efficient, as it is a single request. |
770 | |
884 | |
771 | =cut |
885 | =cut |
772 | |
886 | |
773 | sub aio_load($$;$) { |
887 | sub aio_load($$;$) { |
774 | my ($path, undef, $cb) = @_; |
888 | my ($path, undef, $cb) = @_; |
… | |
… | |
794 | =item aio_copy $srcpath, $dstpath, $callback->($status) |
908 | =item aio_copy $srcpath, $dstpath, $callback->($status) |
795 | |
909 | |
796 | Try to copy the I<file> (directories not supported as either source or |
910 | Try to copy the I<file> (directories not supported as either source or |
797 | destination) from C<$srcpath> to C<$dstpath> and call the callback with |
911 | destination) from C<$srcpath> to C<$dstpath> and call the callback with |
798 | a status of C<0> (ok) or C<-1> (error, see C<$!>). |
912 | a status of C<0> (ok) or C<-1> (error, see C<$!>). |
|
|
913 | |
|
|
914 | Existing destination files will be truncated. |
799 | |
915 | |
800 | This is a composite request that creates the destination file with |
916 | This is a composite request that creates the destination file with |
801 | mode 0200 and copies the contents of the source file into it using |
917 | mode 0200 and copies the contents of the source file into it using |
802 | C<aio_sendfile>, followed by restoring atime, mtime, access mode and |
918 | C<aio_sendfile>, followed by restoring atime, mtime, access mode and |
803 | uid/gid, in that order. |
919 | uid/gid, in that order. |
… | |
… | |
913 | Scans a directory (similar to C<aio_readdir>) but additionally tries to |
1029 | Scans a directory (similar to C<aio_readdir>) but additionally tries to |
914 | efficiently separate the entries of directory C<$path> into two sets of |
1030 | efficiently separate the entries of directory C<$path> into two sets of |
915 | names, directories you can recurse into (directories), and ones you cannot |
1031 | names, directories you can recurse into (directories), and ones you cannot |
916 | recurse into (everything else, including symlinks to directories). |
1032 | recurse into (everything else, including symlinks to directories). |
917 | |
1033 | |
918 | C<aio_scandir> is a composite request that creates of many sub requests_ |
1034 | C<aio_scandir> is a composite request that generates many sub requests. |
919 | C<$maxreq> specifies the maximum number of outstanding aio requests that |
1035 | C<$maxreq> specifies the maximum number of outstanding aio requests that |
920 | this function generates. If it is C<< <= 0 >>, then a suitable default |
1036 | this function generates. If it is C<< <= 0 >>, then a suitable default |
921 | will be chosen (currently 4). |
1037 | will be chosen (currently 4). |
922 | |
1038 | |
923 | On error, the callback is called without arguments, otherwise it receives |
1039 | On error, the callback is called without arguments, otherwise it receives |
… | |
… | |
1057 | } |
1173 | } |
1058 | |
1174 | |
1059 | =item aio_rmtree $pathname, $callback->($status) |
1175 | =item aio_rmtree $pathname, $callback->($status) |
1060 | |
1176 | |
1061 | Delete a directory tree starting (and including) C<$path>, return the |
1177 | Delete a directory tree starting (and including) C<$path>, return the |
1062 | status of the final C<rmdir> only. This is a composite request that |
1178 | status of the final C<rmdir> only. This is a composite request that |
1063 | uses C<aio_scandir> to recurse into and rmdir directories, and unlink |
1179 | uses C<aio_scandir> to recurse into and rmdir directories, and unlink |
1064 | everything else. |
1180 | everything else. |
1065 | |
1181 | |
1066 | =cut |
1182 | =cut |
1067 | |
1183 | |
… | |
… | |
1088 | add $grp $dirgrp; |
1204 | add $grp $dirgrp; |
1089 | }; |
1205 | }; |
1090 | |
1206 | |
1091 | $grp |
1207 | $grp |
1092 | } |
1208 | } |
|
|
1209 | |
|
|
1210 | =item aio_fcntl $fh, $cmd, $arg, $callback->($status) |
|
|
1211 | |
|
|
1212 | =item aio_ioctl $fh, $request, $buf, $callback->($status) |
|
|
1213 | |
|
|
1214 | These work just like the C<fcntl> and C<ioctl> built-in functions, except |
|
|
1215 | they execute asynchronously and pass the return value to the callback. |
|
|
1216 | |
|
|
1217 | Both calls can be used for a lot of things, some of which make more sense |
|
|
1218 | to run asynchronously in their own thread, while some others make less |
|
|
1219 | sense. For example, calls that block waiting for external events, such |
|
|
1220 | as locking, will also lock down an I/O thread while it is waiting, which |
|
|
1221 | can deadlock the whole I/O system. At the same time, there might be no |
|
|
1222 | alternative to using a thread to wait. |
|
|
1223 | |
|
|
1224 | So in general, you should only use these calls for things that do |
|
|
1225 | (filesystem) I/O, not for things that wait for other events (network, |
|
|
1226 | other processes), although if you are careful and know what you are doing, |
|
|
1227 | you still can. |
|
|
1228 | |
|
|
1229 | The following constants are available (missing ones are, as usual C<0>): |
|
|
1230 | |
|
|
1231 | C<F_DUPFD_CLOEXEC>, |
|
|
1232 | |
|
|
1233 | C<F_OFD_GETLK>, C<F_OFD_SETLK>, C<F_OFD_GETLKW>, |
|
|
1234 | |
|
|
1235 | C<FIFREEZE>, C<FITHAW>, C<FITRIM>, C<FICLONE>, C<FICLONERANGE>, C<FIDEDUPERANGE>. |
|
|
1236 | |
|
|
1237 | C<FS_IOC_GETFLAGS>, C<FS_IOC_SETFLAGS>, C<FS_IOC_GETVERSION>, C<FS_IOC_SETVERSION>, |
|
|
1238 | C<FS_IOC_FIEMAP>. |
|
|
1239 | |
|
|
1240 | C<FS_IOC_FSGETXATTR>, C<FS_IOC_FSSETXATTR>, C<FS_IOC_SET_ENCRYPTION_POLICY>, |
|
|
1241 | C<FS_IOC_GET_ENCRYPTION_PWSALT>, C<FS_IOC_GET_ENCRYPTION_POLICY>, C<FS_KEY_DESCRIPTOR_SIZE>. |
|
|
1242 | |
|
|
1243 | C<FS_SECRM_FL>, C<FS_UNRM_FL>, C<FS_COMPR_FL>, C<FS_SYNC_FL>, C<FS_IMMUTABLE_FL>, |
|
|
1244 | C<FS_APPEND_FL>, C<FS_NODUMP_FL>, C<FS_NOATIME_FL>, C<FS_DIRTY_FL>, |
|
|
1245 | C<FS_COMPRBLK_FL>, C<FS_NOCOMP_FL>, C<FS_ENCRYPT_FL>, C<FS_BTREE_FL>, |
|
|
1246 | C<FS_INDEX_FL>, C<FS_JOURNAL_DATA_FL>, C<FS_NOTAIL_FL>, C<FS_DIRSYNC_FL>, C<FS_TOPDIR_FL>, |
|
|
1247 | C<FS_FL_USER_MODIFIABLE>. |
|
|
1248 | |
|
|
1249 | C<FS_XFLAG_REALTIME>, C<FS_XFLAG_PREALLOC>, C<FS_XFLAG_IMMUTABLE>, C<FS_XFLAG_APPEND>, |
|
|
1250 | C<FS_XFLAG_SYNC>, C<FS_XFLAG_NOATIME>, C<FS_XFLAG_NODUMP>, C<FS_XFLAG_RTINHERIT>, |
|
|
1251 | C<FS_XFLAG_PROJINHERIT>, C<FS_XFLAG_NOSYMLINKS>, C<FS_XFLAG_EXTSIZE>, C<FS_XFLAG_EXTSZINHERIT>, |
|
|
1252 | C<FS_XFLAG_NODEFRAG>, C<FS_XFLAG_FILESTREAM>, C<FS_XFLAG_DAX>, C<FS_XFLAG_HASATTR>, |
1093 | |
1253 | |
1094 | =item aio_sync $callback->($status) |
1254 | =item aio_sync $callback->($status) |
1095 | |
1255 | |
1096 | Asynchronously call sync and call the callback when finished. |
1256 | Asynchronously call sync and call the callback when finished. |
1097 | |
1257 | |
… | |
… | |
1166 | }; |
1326 | }; |
1167 | |
1327 | |
1168 | $grp |
1328 | $grp |
1169 | } |
1329 | } |
1170 | |
1330 | |
1171 | =item aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
1331 | =item aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status) |
1172 | |
1332 | |
1173 | This is a rather advanced IO::AIO call, which only works on mmap(2)ed |
1333 | This is a rather advanced IO::AIO call, which only works on mmap(2)ed |
1174 | scalars (see the C<IO::AIO::mmap> function, although it also works on data |
1334 | scalars (see the C<IO::AIO::mmap> function, although it also works on data |
1175 | scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the |
1335 | scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the |
1176 | scalar must only be modified in-place while an aio operation is pending on |
1336 | scalar must only be modified in-place while an aio operation is pending on |
… | |
… | |
1178 | |
1338 | |
1179 | It calls the C<msync> function of your OS, if available, with the memory |
1339 | It calls the C<msync> function of your OS, if available, with the memory |
1180 | area starting at C<$offset> in the string and ending C<$length> bytes |
1340 | area starting at C<$offset> in the string and ending C<$length> bytes |
1181 | later. If C<$length> is negative, counts from the end, and if C<$length> |
1341 | later. If C<$length> is negative, counts from the end, and if C<$length> |
1182 | is C<undef>, then it goes till the end of the string. The flags can be |
1342 | is C<undef>, then it goes till the end of the string. The flags can be |
1183 | a combination of C<IO::AIO::MS_ASYNC>, C<IO::AIO::MS_INVALIDATE> and |
1343 | either C<IO::AIO::MS_ASYNC> or C<IO::AIO::MS_SYNC>, plus an optional |
1184 | C<IO::AIO::MS_SYNC>. |
1344 | C<IO::AIO::MS_INVALIDATE>. |
1185 | |
1345 | |
1186 | =item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
1346 | =item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
1187 | |
1347 | |
1188 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
1348 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
1189 | scalars. |
1349 | scalars. |
1190 | |
1350 | |
1191 | It touches (reads or writes) all memory pages in the specified |
1351 | It touches (reads or writes) all memory pages in the specified |
1192 | range inside the scalar. All caveats and parameters are the same |
1352 | range inside the scalar. All caveats and parameters are the same |
1193 | as for C<aio_msync>, above, except for flags, which must be either |
1353 | as for C<aio_msync>, above, except for flags, which must be either |
1194 | C<0> (which reads all pages and ensures they are instantiated) or |
1354 | C<0> (which reads all pages and ensures they are instantiated) or |
1195 | C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and |
1355 | C<IO::AIO::MT_MODIFY>, which modifies the memory pages (by reading and |
1196 | writing an octet from it, which dirties the page). |
1356 | writing an octet from it, which dirties the page). |
1197 | |
1357 | |
1198 | =item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
1358 | =item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
1199 | |
1359 | |
1200 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
1360 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
… | |
… | |
1231 | documented under L<MISCELLANEOUS FUNCTIONS>. |
1391 | documented under L<MISCELLANEOUS FUNCTIONS>. |
1232 | |
1392 | |
1233 | Example: asynchronously lock all current and future pages into memory. |
1393 | Example: asynchronously lock all current and future pages into memory. |
1234 | |
1394 | |
1235 | aio_mlockall IO::AIO::MCL_FUTURE; |
1395 | aio_mlockall IO::AIO::MCL_FUTURE; |
|
|
1396 | |
|
|
1397 | =item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents) |
|
|
1398 | |
|
|
1399 | Queries the extents of the given file (by calling the Linux C<FIEMAP> |
|
|
1400 | ioctl, see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If |
|
|
1401 | the ioctl is not available on your OS, then this request will fail with |
|
|
1402 | C<ENOSYS>. |
|
|
1403 | |
|
|
1404 | C<$start> is the starting offset to query extents for, C<$length> is the |
|
|
1405 | size of the range to query - if it is C<undef>, then the whole file will |
|
|
1406 | be queried. |
|
|
1407 | |
|
|
1408 | C<$flags> is a combination of flags (C<IO::AIO::FIEMAP_FLAG_SYNC> or |
|
|
1409 | C<IO::AIO::FIEMAP_FLAG_XATTR> - C<IO::AIO::FIEMAP_FLAGS_COMPAT> is also |
|
|
1410 | exported), and is normally C<0> or C<IO::AIO::FIEMAP_FLAG_SYNC> to query |
|
|
1411 | the data portion. |
|
|
1412 | |
|
|
1413 | C<$count> is the maximum number of extent records to return. If it is |
|
|
1414 | C<undef>, then IO::AIO queries all extents of the range. As a very special |
|
|
1415 | case, if it is C<0>, then the callback receives the number of extents |
|
|
1416 | instead of the extents themselves (which is unreliable, see below). |
|
|
1417 | |
|
|
1418 | If an error occurs, the callback receives no arguments. The special |
|
|
1419 | C<errno> value C<IO::AIO::EBADR> is available to test for flag errors. |
|
|
1420 | |
|
|
1421 | Otherwise, the callback receives an array reference with extent |
|
|
1422 | structures. Each extent structure is an array reference itself, with the |
|
|
1423 | following members: |
|
|
1424 | |
|
|
1425 | [$logical, $physical, $length, $flags] |
|
|
1426 | |
|
|
1427 | Flags is any combination of the following flag values (typically either C<0> |
|
|
1428 | or C<IO::AIO::FIEMAP_EXTENT_LAST> (1)): |
|
|
1429 | |
|
|
1430 | C<IO::AIO::FIEMAP_EXTENT_LAST>, C<IO::AIO::FIEMAP_EXTENT_UNKNOWN>, |
|
|
1431 | C<IO::AIO::FIEMAP_EXTENT_DELALLOC>, C<IO::AIO::FIEMAP_EXTENT_ENCODED>, |
|
|
1432 | C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>, |
|
|
1433 | C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>, |
|
|
1434 | C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or |
|
|
1435 | C<IO::AIO::FIEMAP_EXTENT_SHARED>. |
|
|
1436 | |
|
|
1437 | At the time of this writing (Linux 3.2), this request is unreliable unless |
|
|
1438 | C<$count> is C<undef>, as the kernel has all sorts of bugs preventing |
|
|
1439 | it to return all extents of a range for files with a large number of |
|
|
1440 | extents. The code (only) works around all these issues if C<$count> is |
|
|
1441 | C<undef>. |
1236 | |
1442 | |
1237 | =item aio_group $callback->(...) |
1443 | =item aio_group $callback->(...) |
1238 | |
1444 | |
1239 | This is a very special aio request: Instead of doing something, it is a |
1445 | This is a very special aio request: Instead of doing something, it is a |
1240 | container for other aio requests, which is useful if you want to bundle |
1446 | container for other aio requests, which is useful if you want to bundle |
… | |
… | |
1324 | aio_stat [$etcdir, "passwd"], sub { |
1530 | aio_stat [$etcdir, "passwd"], sub { |
1325 | # yay |
1531 | # yay |
1326 | }; |
1532 | }; |
1327 | }; |
1533 | }; |
1328 | |
1534 | |
1329 | That C<aio_wd> is a request and not a normal function shows that creating |
1535 | The fact that C<aio_wd> is a request and not a normal function shows that |
1330 | an IO::AIO::WD object is itself a potentially blocking operation, which is |
1536 | creating an IO::AIO::WD object is itself a potentially blocking operation, |
1331 | why it is done asynchronously. |
1537 | which is why it is done asynchronously. |
1332 | |
1538 | |
1333 | To stat the directory obtained with C<aio_wd> above, one could write |
1539 | To stat the directory obtained with C<aio_wd> above, one could write |
1334 | either of the following three request calls: |
1540 | either of the following three request calls: |
1335 | |
1541 | |
1336 | aio_lstat "/etc" , sub { ... # pathname as normal string |
1542 | aio_lstat "/etc" , sub { ... # pathname as normal string |
… | |
… | |
1353 | There are some caveats: when directories get renamed (or deleted), the |
1559 | There are some caveats: when directories get renamed (or deleted), the |
1354 | pathname string doesn't change, so will point to the new directory (or |
1560 | pathname string doesn't change, so will point to the new directory (or |
1355 | nowhere at all), while the directory fd, if available on the system, |
1561 | nowhere at all), while the directory fd, if available on the system, |
1356 | will still point to the original directory. Most functions accepting a |
1562 | will still point to the original directory. Most functions accepting a |
1357 | pathname will use the directory fd on newer systems, and the string on |
1563 | pathname will use the directory fd on newer systems, and the string on |
1358 | older systems. Some functions (such as realpath) will always rely on the |
1564 | older systems. Some functions (such as C<aio_realpath>) will always rely on |
1359 | string form of the pathname. |
1565 | the string form of the pathname. |
1360 | |
1566 | |
1361 | So this fucntionality is mainly useful to get some protection against |
1567 | So this functionality is mainly useful to get some protection against |
1362 | C<chdir>, to easily get an absolute path out of a relative path for future |
1568 | C<chdir>, to easily get an absolute path out of a relative path for future |
1363 | reference, and to speed up doing many operations in the same directory |
1569 | reference, and to speed up doing many operations in the same directory |
1364 | (e.g. when stat'ing all files in a directory). |
1570 | (e.g. when stat'ing all files in a directory). |
1365 | |
1571 | |
1366 | The following functions implement this working directory abstraction: |
1572 | The following functions implement this working directory abstraction: |
… | |
… | |
1379 | passing C<undef> as working directory component of a pathname fails the |
1585 | passing C<undef> as working directory component of a pathname fails the |
1380 | request with C<ENOENT>, there is often no need for error checking in the |
1586 | request with C<ENOENT>, there is often no need for error checking in the |
1381 | C<aio_wd> callback, as future requests using the value will fail in the |
1587 | C<aio_wd> callback, as future requests using the value will fail in the |
1382 | expected way. |
1588 | expected way. |
1383 | |
1589 | |
1384 | If this call isn't available because your OS lacks it or it couldn't be |
|
|
1385 | detected, it will be emulated by calling C<fsync> instead. |
|
|
1386 | |
|
|
1387 | =item IO::AIO::CWD |
1590 | =item IO::AIO::CWD |
1388 | |
1591 | |
1389 | This is a compiletime constant (object) that represents the process |
1592 | This is a compiletime constant (object) that represents the process |
1390 | current working directory. |
1593 | current working directory. |
1391 | |
1594 | |
1392 | Specifying this object as working directory object for a pathname is as |
1595 | Specifying this object as working directory object for a pathname is as if |
1393 | if the pathname would be specified directly, without a directory object, |
1596 | the pathname would be specified directly, without a directory object. For |
1394 | e.g., these calls are functionally identical: |
1597 | example, these calls are functionally identical: |
1395 | |
1598 | |
1396 | aio_stat "somefile", sub { ... }; |
1599 | aio_stat "somefile", sub { ... }; |
1397 | aio_stat [IO::AIO::CWD, "somefile"], sub { ... }; |
1600 | aio_stat [IO::AIO::CWD, "somefile"], sub { ... }; |
1398 | |
1601 | |
1399 | =back |
1602 | =back |
1400 | |
1603 | |
|
|
1604 | To recover the path associated with an IO::AIO::WD object, you can use |
|
|
1605 | C<aio_realpath>: |
|
|
1606 | |
|
|
1607 | aio_realpath $wd, sub { |
|
|
1608 | warn "path is $_[0]\n"; |
|
|
1609 | }; |
|
|
1610 | |
|
|
1611 | Currently, C<aio_statvfs> always, and C<aio_rename> and C<aio_rmdir> |
|
|
1612 | sometimes, fall back to using an absolue path. |
1401 | |
1613 | |
1402 | =head2 IO::AIO::REQ CLASS |
1614 | =head2 IO::AIO::REQ CLASS |
1403 | |
1615 | |
1404 | All non-aggregate C<aio_*> functions return an object of this class when |
1616 | All non-aggregate C<aio_*> functions return an object of this class when |
1405 | called in non-void context. |
1617 | called in non-void context. |
… | |
… | |
1583 | |
1795 | |
1584 | See C<poll_cb> for an example. |
1796 | See C<poll_cb> for an example. |
1585 | |
1797 | |
1586 | =item IO::AIO::poll_cb |
1798 | =item IO::AIO::poll_cb |
1587 | |
1799 | |
1588 | Process some outstanding events on the result pipe. You have to call |
1800 | Process some requests that have reached the result phase (i.e. they have |
|
|
1801 | been executed but the results are not yet reported). You have to call |
|
|
1802 | this "regularly" to finish outstanding requests. |
|
|
1803 | |
1589 | this regularly. Returns C<0> if all events could be processed (or there |
1804 | Returns C<0> if all events could be processed (or there were no |
1590 | were no events to process), or C<-1> if it returned earlier for whatever |
1805 | events to process), or C<-1> if it returned earlier for whatever |
1591 | reason. Returns immediately when no events are outstanding. The amount of |
1806 | reason. Returns immediately when no events are outstanding. The amount |
1592 | events processed depends on the settings of C<IO::AIO::max_poll_req> and |
1807 | of events processed depends on the settings of C<IO::AIO::max_poll_req>, |
1593 | C<IO::AIO::max_poll_time>. |
1808 | C<IO::AIO::max_poll_time> and C<IO::AIO::max_outstanding>. |
1594 | |
1809 | |
1595 | If not all requests were processed for whatever reason, the filehandle |
1810 | If not all requests were processed for whatever reason, the poll file |
1596 | will still be ready when C<poll_cb> returns, so normally you don't have to |
1811 | descriptor will still be ready when C<poll_cb> returns, so normally you |
1597 | do anything special to have it called later. |
1812 | don't have to do anything special to have it called later. |
1598 | |
1813 | |
1599 | Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes |
1814 | Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes |
1600 | ready, it can be beneficial to call this function from loops which submit |
1815 | ready, it can be beneficial to call this function from loops which submit |
1601 | a lot of requests, to make sure the results get processed when they become |
1816 | a lot of requests, to make sure the results get processed when they become |
1602 | available and not just when the loop is finished and the event loop takes |
1817 | available and not just when the loop is finished and the event loop takes |
… | |
… | |
1611 | poll => 'r', async => 1, |
1826 | poll => 'r', async => 1, |
1612 | cb => \&IO::AIO::poll_cb); |
1827 | cb => \&IO::AIO::poll_cb); |
1613 | |
1828 | |
1614 | =item IO::AIO::poll_wait |
1829 | =item IO::AIO::poll_wait |
1615 | |
1830 | |
1616 | If there are any outstanding requests and none of them in the result |
1831 | Wait until either at least one request is in the result phase or no |
1617 | phase, wait till the result filehandle becomes ready for reading (simply |
1832 | requests are outstanding anymore. |
1618 | does a C<select> on the filehandle. This is useful if you want to |
1833 | |
1619 | synchronously wait for some requests to finish). |
1834 | This is useful if you want to synchronously wait for some requests to |
|
|
1835 | become ready, without actually handling them. |
1620 | |
1836 | |
1621 | See C<nreqs> for an example. |
1837 | See C<nreqs> for an example. |
1622 | |
1838 | |
1623 | =item IO::AIO::poll |
1839 | =item IO::AIO::poll |
1624 | |
1840 | |
… | |
… | |
1745 | |
1961 | |
1746 | This is a very bad function to use in interactive programs because it |
1962 | This is a very bad function to use in interactive programs because it |
1747 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
1963 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
1748 | use an C<aio_group> together with a feed callback. |
1964 | use an C<aio_group> together with a feed callback. |
1749 | |
1965 | |
1750 | It's main use is in scripts without an event loop - when you want to stat |
1966 | Its main use is in scripts without an event loop - when you want to stat |
1751 | a lot of files, you can write somehting like this: |
1967 | a lot of files, you can write something like this: |
1752 | |
1968 | |
1753 | IO::AIO::max_outstanding 32; |
1969 | IO::AIO::max_outstanding 32; |
1754 | |
1970 | |
1755 | for my $path (...) { |
1971 | for my $path (...) { |
1756 | aio_stat $path , ...; |
1972 | aio_stat $path , ...; |
… | |
… | |
1795 | |
2011 | |
1796 | =back |
2012 | =back |
1797 | |
2013 | |
1798 | =head3 MISCELLANEOUS FUNCTIONS |
2014 | =head3 MISCELLANEOUS FUNCTIONS |
1799 | |
2015 | |
1800 | IO::AIO implements some functions that might be useful, but are not |
2016 | IO::AIO implements some functions that are useful when you want to use |
1801 | asynchronous. |
2017 | some "Advanced I/O" function not available to in Perl, without going the |
|
|
2018 | "Asynchronous I/O" route. Many of these have an asynchronous C<aio_*> |
|
|
2019 | counterpart. |
1802 | |
2020 | |
1803 | =over 4 |
2021 | =over 4 |
|
|
2022 | |
|
|
2023 | =item $numfd = IO::AIO::get_fdlimit |
|
|
2024 | |
|
|
2025 | This function is I<EXPERIMENTAL> and subject to change. |
|
|
2026 | |
|
|
2027 | Tries to find the current file descriptor limit and returns it, or |
|
|
2028 | C<undef> and sets C<$!> in case of an error. The limit is one larger than |
|
|
2029 | the highest valid file descriptor number. |
|
|
2030 | |
|
|
2031 | =item IO::AIO::min_fdlimit [$numfd] |
|
|
2032 | |
|
|
2033 | This function is I<EXPERIMENTAL> and subject to change. |
|
|
2034 | |
|
|
2035 | Try to increase the current file descriptor limit(s) to at least C<$numfd> |
|
|
2036 | by changing the soft or hard file descriptor resource limit. If C<$numfd> |
|
|
2037 | is missing, it will try to set a very high limit, although this is not |
|
|
2038 | recommended when you know the actual minimum that you require. |
|
|
2039 | |
|
|
2040 | If the limit cannot be raised enough, the function makes a best-effort |
|
|
2041 | attempt to increase the limit as much as possible, using various |
|
|
2042 | tricks, while still failing. You can query the resulting limit using |
|
|
2043 | C<IO::AIO::get_fdlimit>. |
|
|
2044 | |
|
|
2045 | If an error occurs, returns C<undef> and sets C<$!>, otherwise returns |
|
|
2046 | true. |
1804 | |
2047 | |
1805 | =item IO::AIO::sendfile $ofh, $ifh, $offset, $count |
2048 | =item IO::AIO::sendfile $ofh, $ifh, $offset, $count |
1806 | |
2049 | |
1807 | Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>, |
2050 | Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>, |
1808 | but is blocking (this makes most sense if you know the input data is |
2051 | but is blocking (this makes most sense if you know the input data is |
… | |
… | |
1825 | =item IO::AIO::madvise $scalar, $offset, $len, $advice |
2068 | =item IO::AIO::madvise $scalar, $offset, $len, $advice |
1826 | |
2069 | |
1827 | Simply calls the C<posix_madvise> function (see its |
2070 | Simply calls the C<posix_madvise> function (see its |
1828 | manpage for details). The following advice constants are |
2071 | manpage for details). The following advice constants are |
1829 | available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>, |
2072 | available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>, |
1830 | C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>. |
2073 | C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, |
|
|
2074 | C<IO::AIO::MADV_DONTNEED>. |
|
|
2075 | |
|
|
2076 | If C<$offset> is negative, counts from the end. If C<$length> is negative, |
|
|
2077 | the remaining length of the C<$scalar> is used. If possible, C<$length> |
|
|
2078 | will be reduced to fit into the C<$scalar>. |
1831 | |
2079 | |
1832 | On systems that do not implement C<posix_madvise>, this function returns |
2080 | On systems that do not implement C<posix_madvise>, this function returns |
1833 | ENOSYS, otherwise the return value of C<posix_madvise>. |
2081 | ENOSYS, otherwise the return value of C<posix_madvise>. |
1834 | |
2082 | |
1835 | =item IO::AIO::mprotect $scalar, $offset, $len, $protect |
2083 | =item IO::AIO::mprotect $scalar, $offset, $len, $protect |
… | |
… | |
1837 | Simply calls the C<mprotect> function on the preferably AIO::mmap'ed |
2085 | Simply calls the C<mprotect> function on the preferably AIO::mmap'ed |
1838 | $scalar (see its manpage for details). The following protect |
2086 | $scalar (see its manpage for details). The following protect |
1839 | constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>, |
2087 | constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>, |
1840 | C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>. |
2088 | C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>. |
1841 | |
2089 | |
|
|
2090 | If C<$offset> is negative, counts from the end. If C<$length> is negative, |
|
|
2091 | the remaining length of the C<$scalar> is used. If possible, C<$length> |
|
|
2092 | will be reduced to fit into the C<$scalar>. |
|
|
2093 | |
1842 | On systems that do not implement C<mprotect>, this function returns |
2094 | On systems that do not implement C<mprotect>, this function returns |
1843 | ENOSYS, otherwise the return value of C<mprotect>. |
2095 | ENOSYS, otherwise the return value of C<mprotect>. |
1844 | |
2096 | |
1845 | =item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
2097 | =item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
1846 | |
2098 | |
1847 | Memory-maps a file (or anonymous memory range) and attaches it to the |
2099 | Memory-maps a file (or anonymous memory range) and attaches it to the |
1848 | given C<$scalar>, which will act like a string scalar. |
2100 | given C<$scalar>, which will act like a string scalar. Returns true on |
|
|
2101 | success, and false otherwise. |
1849 | |
2102 | |
|
|
2103 | The scalar must exist, but its contents do not matter - this means you |
|
|
2104 | cannot use a nonexistant array or hash element. When in doubt, C<undef> |
|
|
2105 | the scalar first. |
|
|
2106 | |
1850 | The only operations allowed on the scalar are C<substr>/C<vec> that don't |
2107 | The only operations allowed on the mmapped scalar are C<substr>/C<vec>, |
1851 | change the string length, and most read-only operations such as copying it |
2108 | which don't change the string length, and most read-only operations such |
1852 | or searching it with regexes and so on. |
2109 | as copying it or searching it with regexes and so on. |
1853 | |
2110 | |
1854 | Anything else is unsafe and will, at best, result in memory leaks. |
2111 | Anything else is unsafe and will, at best, result in memory leaks. |
1855 | |
2112 | |
1856 | The memory map associated with the C<$scalar> is automatically removed |
2113 | The memory map associated with the C<$scalar> is automatically removed |
1857 | when the C<$scalar> is destroyed, or when the C<IO::AIO::mmap> or |
2114 | when the C<$scalar> is undef'd or destroyed, or when the C<IO::AIO::mmap> |
1858 | C<IO::AIO::munmap> functions are called. |
2115 | or C<IO::AIO::munmap> functions are called on it. |
1859 | |
2116 | |
1860 | This calls the C<mmap>(2) function internally. See your system's manual |
2117 | This calls the C<mmap>(2) function internally. See your system's manual |
1861 | page for details on the C<$length>, C<$prot> and C<$flags> parameters. |
2118 | page for details on the C<$length>, C<$prot> and C<$flags> parameters. |
1862 | |
2119 | |
1863 | The C<$length> must be larger than zero and smaller than the actual |
2120 | The C<$length> must be larger than zero and smaller than the actual |
1864 | filesize. |
2121 | filesize. |
1865 | |
2122 | |
1866 | C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>, |
2123 | C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>, |
1867 | C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>, |
2124 | C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>, |
1868 | |
2125 | |
1869 | C<$flags> can be a combination of C<IO::AIO::MAP_SHARED> or |
2126 | C<$flags> can be a combination of |
1870 | C<IO::AIO::MAP_PRIVATE>, or a number of system-specific flags (when |
2127 | C<IO::AIO::MAP_SHARED> or |
1871 | not available, the are defined as 0): C<IO::AIO::MAP_ANONYMOUS> |
2128 | C<IO::AIO::MAP_PRIVATE>, |
|
|
2129 | or a number of system-specific flags (when not available, the are C<0>): |
1872 | (which is set to C<MAP_ANON> if your system only provides this |
2130 | C<IO::AIO::MAP_ANONYMOUS> (which is set to C<MAP_ANON> if your system only provides this constant), |
1873 | constant), C<IO::AIO::MAP_HUGETLB>, C<IO::AIO::MAP_LOCKED>, |
2131 | C<IO::AIO::MAP_LOCKED>, |
1874 | C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or |
2132 | C<IO::AIO::MAP_NORESERVE>, |
|
|
2133 | C<IO::AIO::MAP_POPULATE>, |
1875 | C<IO::AIO::MAP_NONBLOCK> |
2134 | C<IO::AIO::MAP_NONBLOCK>, |
|
|
2135 | C<IO::AIO::MAP_FIXED>, |
|
|
2136 | C<IO::AIO::MAP_GROWSDOWN>, |
|
|
2137 | C<IO::AIO::MAP_32BIT>, |
|
|
2138 | C<IO::AIO::MAP_HUGETLB> or |
|
|
2139 | C<IO::AIO::MAP_STACK>. |
1876 | |
2140 | |
1877 | If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed. |
2141 | If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed. |
1878 | |
2142 | |
1879 | C<$offset> is the offset from the start of the file - it generally must be |
2143 | C<$offset> is the offset from the start of the file - it generally must be |
1880 | a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>. |
2144 | a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>. |
… | |
… | |
1905 | |
2169 | |
1906 | Calls the C<munlockall> function. |
2170 | Calls the C<munlockall> function. |
1907 | |
2171 | |
1908 | On systems that do not implement C<munlockall>, this function returns |
2172 | On systems that do not implement C<munlockall>, this function returns |
1909 | ENOSYS, otherwise the return value of C<munlockall>. |
2173 | ENOSYS, otherwise the return value of C<munlockall>. |
|
|
2174 | |
|
|
2175 | =item IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags |
|
|
2176 | |
|
|
2177 | Calls the GNU/Linux C<splice(2)> syscall, if available. If C<$r_off> or |
|
|
2178 | C<$w_off> are C<undef>, then C<NULL> is passed for these, otherwise they |
|
|
2179 | should be the file offset. |
|
|
2180 | |
|
|
2181 | C<$r_fh> and C<$w_fh> should not refer to the same file, as splice might |
|
|
2182 | silently corrupt the data in this case. |
|
|
2183 | |
|
|
2184 | The following symbol flag values are available: C<IO::AIO::SPLICE_F_MOVE>, |
|
|
2185 | C<IO::AIO::SPLICE_F_NONBLOCK>, C<IO::AIO::SPLICE_F_MORE> and |
|
|
2186 | C<IO::AIO::SPLICE_F_GIFT>. |
|
|
2187 | |
|
|
2188 | See the C<splice(2)> manpage for details. |
|
|
2189 | |
|
|
2190 | =item IO::AIO::tee $r_fh, $w_fh, $length, $flags |
|
|
2191 | |
|
|
2192 | Calls the GNU/Linux C<tee(2)> syscall, see its manpage and the |
|
|
2193 | description for C<IO::AIO::splice> above for details. |
|
|
2194 | |
|
|
2195 | =item $actual_size = IO::AIO::pipesize $r_fh[, $new_size] |
|
|
2196 | |
|
|
2197 | Attempts to query or change the pipe buffer size. Obviously works only |
|
|
2198 | on pipes, and currently works only on GNU/Linux systems, and fails with |
|
|
2199 | C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer |
|
|
2200 | size on other systems, drop me a note. |
|
|
2201 | |
|
|
2202 | =item ($rfh, $wfh) = IO::AIO::pipe2 [$flags] |
|
|
2203 | |
|
|
2204 | This is a direct interface to the Linux L<pipe2(2)> system call. If |
|
|
2205 | C<$flags> is missing or C<0>, then this should be the same as a call to |
|
|
2206 | perl's built-in C<pipe> function and create a new pipe, and works on |
|
|
2207 | systems that lack the pipe2 syscall. On win32, this case invokes C<_pipe |
|
|
2208 | (..., 4096, O_BINARY)>. |
|
|
2209 | |
|
|
2210 | If C<$flags> is non-zero, it tries to invoke the pipe2 system call with |
|
|
2211 | the given flags (Linux 2.6.27, glibc 2.9). |
|
|
2212 | |
|
|
2213 | On success, the read and write file handles are returned. |
|
|
2214 | |
|
|
2215 | On error, nothing will be returned. If the pipe2 syscall is missing and |
|
|
2216 | C<$flags> is non-zero, fails with C<ENOSYS>. |
|
|
2217 | |
|
|
2218 | Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the |
|
|
2219 | time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and |
|
|
2220 | C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported. |
|
|
2221 | |
|
|
2222 | Example: create a pipe race-free w.r.t. threads and fork: |
|
|
2223 | |
|
|
2224 | my ($rfh, $wfh) = IO::AIO::pipe2 IO::AIO::O_CLOEXEC |
|
|
2225 | or die "pipe2: $!\n"; |
|
|
2226 | |
|
|
2227 | =item $fh = IO::AIO::eventfd [$initval, [$flags]] |
|
|
2228 | |
|
|
2229 | This is a direct interface to the Linux L<eventfd(2)> system call. The |
|
|
2230 | (unhelpful) defaults for C<$initval> and C<$flags> are C<0> for both. |
|
|
2231 | |
|
|
2232 | On success, the new eventfd filehandle is returned, otherwise returns |
|
|
2233 | C<undef>. If the eventfd syscall is missing, fails with C<ENOSYS>. |
|
|
2234 | |
|
|
2235 | Please refer to L<eventfd(2)> for more info on this call. |
|
|
2236 | |
|
|
2237 | The following symbol flag values are available: C<IO::AIO::EFD_CLOEXEC>, |
|
|
2238 | C<IO::AIO::EFD_NONBLOCK> and C<IO::AIO::EFD_SEMAPHORE> (Linux 2.6.30). |
|
|
2239 | |
|
|
2240 | Example: create a new eventfd filehandle: |
|
|
2241 | |
|
|
2242 | $fh = IO::AIO::eventfd 0, IO::AIO::O_CLOEXEC |
|
|
2243 | or die "eventfd: $!\n"; |
|
|
2244 | |
|
|
2245 | =item $fh = IO::AIO::timerfd_create $clockid[, $flags] |
|
|
2246 | |
|
|
2247 | This is a direct interface to the Linux L<timerfd_create(2)> system call. The |
|
|
2248 | (unhelpful) default for C<$flags> is C<0>. |
|
|
2249 | |
|
|
2250 | On success, the new timerfd filehandle is returned, otherwise returns |
|
|
2251 | C<undef>. If the eventfd syscall is missing, fails with C<ENOSYS>. |
|
|
2252 | |
|
|
2253 | Please refer to L<timerfd_create(2)> for more info on this call. |
|
|
2254 | |
|
|
2255 | The following C<$clockid> values are |
|
|
2256 | available: C<IO::AIO::CLOCK_REALTIME>, C<IO::AIO::CLOCK_MONOTONIC> |
|
|
2257 | C<IO::AIO::CLOCK_CLOCK_BOOTTIME> (Linux 3.15) |
|
|
2258 | C<IO::AIO::CLOCK_CLOCK_REALTIME_ALARM> (Linux 3.11) and |
|
|
2259 | C<IO::AIO::CLOCK_CLOCK_BOOTTIME_ALARM> (Linux 3.11). |
|
|
2260 | |
|
|
2261 | The following C<$flags> values are available (Linux |
|
|
2262 | 2.6.27): C<IO::AIO::TFD_NONBLOCK> and C<IO::AIO::TFD_CLOEXEC>. |
|
|
2263 | |
|
|
2264 | Example: create a new timerfd and set it to one-second repeated alarms, |
|
|
2265 | then wait for two alarms: |
|
|
2266 | |
|
|
2267 | my $fh = IO::AIO::timerfd_create IO::AIO::CLOCK_BOOTTIME, IO::AIO::TFD_CLOEXEC |
|
|
2268 | or die "timerfd_create: $!\n"; |
|
|
2269 | |
|
|
2270 | defined IO::AIO::timerfd_settime $fh, 0, 1, 1 |
|
|
2271 | or die "timerfd_settime: $!\n"; |
|
|
2272 | |
|
|
2273 | for (1..2) { |
|
|
2274 | 8 == sysread $fh, my $buf, 8 |
|
|
2275 | or die "timerfd read failure\n"; |
|
|
2276 | |
|
|
2277 | printf "number of expirations (likely 1): %d\n", |
|
|
2278 | unpack "Q", $buf; |
|
|
2279 | } |
|
|
2280 | |
|
|
2281 | =item ($cur_interval, $cur_value) = IO::AIO::timerfd_settime $fh, $flags, $new_interval, $nbw_value |
|
|
2282 | |
|
|
2283 | This is a direct interface to the Linux L<timerfd_settime(2)> system |
|
|
2284 | call. Please refer to its manpage for more info on this call. |
|
|
2285 | |
|
|
2286 | The new itimerspec is specified using two (possibly fractional) second |
|
|
2287 | values, C<$new_interval> and C<$new_value>). |
|
|
2288 | |
|
|
2289 | On success, the current interval and value are returned (as per |
|
|
2290 | C<timerfd_gettime>). On failure, the empty list is returned. |
|
|
2291 | |
|
|
2292 | The following C<$flags> values are |
|
|
2293 | available: C<IO::AIO::TFD_TIMER_ABSTIME> and |
|
|
2294 | C<IO::AIO::TFD_TIMER_CANCEL_ON_SET>. |
|
|
2295 | |
|
|
2296 | See C<IO::AIO::timerfd_create> for a full example. |
|
|
2297 | |
|
|
2298 | =item ($cur_interval, $cur_value) = IO::AIO::timerfd_gettime $fh |
|
|
2299 | |
|
|
2300 | This is a direct interface to the Linux L<timerfd_gettime(2)> system |
|
|
2301 | call. Please refer to its manpage for more info on this call. |
|
|
2302 | |
|
|
2303 | On success, returns the current values of interval and value for the given |
|
|
2304 | timerfd (as potentially fractional second values). On failure, the empty |
|
|
2305 | list is returned. |
1910 | |
2306 | |
1911 | =back |
2307 | =back |
1912 | |
2308 | |
1913 | =cut |
2309 | =cut |
1914 | |
2310 | |
… | |
… | |
1980 | the process will result in undefined behaviour. Calling it at any time |
2376 | the process will result in undefined behaviour. Calling it at any time |
1981 | will also result in any undefined (by POSIX) behaviour. |
2377 | will also result in any undefined (by POSIX) behaviour. |
1982 | |
2378 | |
1983 | =back |
2379 | =back |
1984 | |
2380 | |
|
|
2381 | =head2 LINUX-SPECIFIC CALLS |
|
|
2382 | |
|
|
2383 | When a call is documented as "linux-specific" then this means it |
|
|
2384 | originated on GNU/Linux. C<IO::AIO> will usually try to autodetect the |
|
|
2385 | availability and compatibility of such calls regardless of the platform |
|
|
2386 | it is compiled on, so platforms such as FreeBSD which often implement |
|
|
2387 | these calls will work. When in doubt, call them and see if they fail wth |
|
|
2388 | C<ENOSYS>. |
|
|
2389 | |
1985 | =head2 MEMORY USAGE |
2390 | =head2 MEMORY USAGE |
1986 | |
2391 | |
1987 | Per-request usage: |
2392 | Per-request usage: |
1988 | |
2393 | |
1989 | Each aio request uses - depending on your architecture - around 100-200 |
2394 | Each aio request uses - depending on your architecture - around 100-200 |
… | |
… | |
2001 | temporary buffers, and each thread requires a stack and other data |
2406 | temporary buffers, and each thread requires a stack and other data |
2002 | structures (usually around 16k-128k, depending on the OS). |
2407 | structures (usually around 16k-128k, depending on the OS). |
2003 | |
2408 | |
2004 | =head1 KNOWN BUGS |
2409 | =head1 KNOWN BUGS |
2005 | |
2410 | |
2006 | Known bugs will be fixed in the next release. |
2411 | Known bugs will be fixed in the next release :) |
|
|
2412 | |
|
|
2413 | =head1 KNOWN ISSUES |
|
|
2414 | |
|
|
2415 | Calls that try to "import" foreign memory areas (such as C<IO::AIO::mmap> |
|
|
2416 | or C<IO::AIO::aio_slurp>) do not work with generic lvalues, such as |
|
|
2417 | non-created hash slots or other scalars I didn't think of. It's best to |
|
|
2418 | avoid such and either use scalar variables or making sure that the scalar |
|
|
2419 | exists (e.g. by storing C<undef>) and isn't "funny" (e.g. tied). |
|
|
2420 | |
|
|
2421 | I am not sure anything can be done about this, so this is considered a |
|
|
2422 | known issue, rather than a bug. |
2007 | |
2423 | |
2008 | =head1 SEE ALSO |
2424 | =head1 SEE ALSO |
2009 | |
2425 | |
2010 | L<AnyEvent::AIO> for easy integration into event loops, L<Coro::AIO> for a |
2426 | L<AnyEvent::AIO> for easy integration into event loops, L<Coro::AIO> for a |
2011 | more natural syntax. |
2427 | more natural syntax. |