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 = '3.72'; |
176 | our $VERSION = 4.74; |
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_sync aio_fsync |
180 | aio_scandir aio_symlink aio_readlink aio_realpath aio_fcntl aio_ioctl |
178 | aio_fdatasync aio_sync_file_range aio_pathsync aio_readahead |
181 | aio_sync aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range |
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182 | aio_pathsync aio_readahead aio_fiemap aio_allocate |
179 | aio_rename aio_link aio_move aio_copy aio_group |
183 | aio_rename aio_rename2 aio_link aio_move aio_copy aio_group |
180 | 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 |
181 | aio_chmod aio_utime aio_truncate |
185 | aio_chmod aio_utime aio_truncate |
182 | aio_msync aio_mtouch aio_mlock aio_mlockall |
186 | aio_msync aio_mtouch aio_mlock aio_mlockall |
183 | aio_statvfs); |
187 | aio_statvfs |
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188 | aio_slurp |
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189 | aio_wd); |
184 | |
190 | |
185 | our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice)); |
191 | our @EXPORT = (@AIO_REQ, qw(aioreq_pri aioreq_nice)); |
186 | our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush |
192 | our @EXPORT_OK = qw(poll_fileno poll_cb poll_wait flush |
187 | min_parallel max_parallel max_idle idle_timeout |
193 | min_parallel max_parallel max_idle idle_timeout |
188 | nreqs nready npending nthreads |
194 | nreqs nready npending nthreads |
189 | max_poll_time max_poll_reqs |
195 | max_poll_time max_poll_reqs |
190 | sendfile fadvise madvise |
196 | sendfile fadvise madvise |
191 | mmap munmap munlock munlockall); |
197 | mmap munmap mremap munlock munlockall); |
192 | |
198 | |
193 | push @AIO_REQ, qw(aio_busy); # not exported |
199 | push @AIO_REQ, qw(aio_busy); # not exported |
194 | |
200 | |
195 | @IO::AIO::GRP::ISA = 'IO::AIO::REQ'; |
201 | @IO::AIO::GRP::ISA = 'IO::AIO::REQ'; |
196 | |
202 | |
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200 | |
206 | |
201 | =head1 FUNCTIONS |
207 | =head1 FUNCTIONS |
202 | |
208 | |
203 | =head2 QUICK OVERVIEW |
209 | =head2 QUICK OVERVIEW |
204 | |
210 | |
205 | This section simply lists the prototypes of the most important functions |
211 | This section simply lists the prototypes most of the functions for |
206 | for quick reference. See the following sections for function-by-function |
212 | quick reference. See the following sections for function-by-function |
207 | documentation. |
213 | documentation. |
208 | |
214 | |
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215 | aio_wd $pathname, $callback->($wd) |
209 | aio_open $pathname, $flags, $mode, $callback->($fh) |
216 | aio_open $pathname, $flags, $mode, $callback->($fh) |
210 | aio_close $fh, $callback->($status) |
217 | aio_close $fh, $callback->($status) |
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218 | aio_seek $fh,$offset,$whence, $callback->($offs) |
211 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
219 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
212 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
220 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
213 | aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval) |
221 | aio_sendfile $out_fh, $in_fh, $in_offset, $length, $callback->($retval) |
214 | aio_readahead $fh,$offset,$length, $callback->($retval) |
222 | aio_readahead $fh,$offset,$length, $callback->($retval) |
215 | aio_stat $fh_or_path, $callback->($status) |
223 | aio_stat $fh_or_path, $callback->($status) |
216 | aio_lstat $fh, $callback->($status) |
224 | aio_lstat $fh, $callback->($status) |
217 | aio_statvfs $fh_or_path, $callback->($statvfs) |
225 | aio_statvfs $fh_or_path, $callback->($statvfs) |
218 | aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
226 | aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
219 | 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) |
220 | aio_truncate $fh_or_path, $offset, $callback->($status) |
229 | aio_truncate $fh_or_path, $offset, $callback->($status) |
221 | 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) |
222 | aio_unlink $pathname, $callback->($status) |
232 | aio_unlink $pathname, $callback->($status) |
223 | aio_mknod $path, $mode, $dev, $callback->($status) |
233 | aio_mknod $pathname, $mode, $dev, $callback->($status) |
224 | aio_link $srcpath, $dstpath, $callback->($status) |
234 | aio_link $srcpath, $dstpath, $callback->($status) |
225 | aio_symlink $srcpath, $dstpath, $callback->($status) |
235 | aio_symlink $srcpath, $dstpath, $callback->($status) |
226 | aio_readlink $path, $callback->($link) |
236 | aio_readlink $pathname, $callback->($link) |
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237 | aio_realpath $pathname, $callback->($path) |
227 | 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) |
228 | aio_mkdir $pathname, $mode, $callback->($status) |
240 | aio_mkdir $pathname, $mode, $callback->($status) |
229 | aio_rmdir $pathname, $callback->($status) |
241 | aio_rmdir $pathname, $callback->($status) |
230 | aio_readdir $pathname, $callback->($entries) |
242 | aio_readdir $pathname, $callback->($entries) |
231 | aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
243 | aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
232 | IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST |
244 | IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST |
233 | IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN |
245 | IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN |
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246 | aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs) |
234 | aio_load $path, $data, $callback->($status) |
247 | aio_load $pathname, $data, $callback->($status) |
235 | aio_copy $srcpath, $dstpath, $callback->($status) |
248 | aio_copy $srcpath, $dstpath, $callback->($status) |
236 | aio_move $srcpath, $dstpath, $callback->($status) |
249 | aio_move $srcpath, $dstpath, $callback->($status) |
237 | aio_scandir $path, $maxreq, $callback->($dirs, $nondirs) |
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238 | aio_rmtree $path, $callback->($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) |
239 | aio_sync $callback->($status) |
253 | aio_sync $callback->($status) |
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254 | aio_syncfs $fh, $callback->($status) |
240 | aio_fsync $fh, $callback->($status) |
255 | aio_fsync $fh, $callback->($status) |
241 | aio_fdatasync $fh, $callback->($status) |
256 | aio_fdatasync $fh, $callback->($status) |
242 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
257 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
243 | aio_pathsync $path, $callback->($status) |
258 | aio_pathsync $pathname, $callback->($status) |
244 | aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
259 | aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status) |
245 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
260 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
246 | aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
261 | aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
247 | aio_mlockall $flags, $callback->($status) |
262 | aio_mlockall $flags, $callback->($status) |
248 | aio_group $callback->(...) |
263 | aio_group $callback->(...) |
249 | aio_nop $callback->() |
264 | aio_nop $callback->() |
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263 | IO::AIO::idle_timeout $seconds |
278 | IO::AIO::idle_timeout $seconds |
264 | IO::AIO::max_outstanding $maxreqs |
279 | IO::AIO::max_outstanding $maxreqs |
265 | IO::AIO::nreqs |
280 | IO::AIO::nreqs |
266 | IO::AIO::nready |
281 | IO::AIO::nready |
267 | IO::AIO::npending |
282 | IO::AIO::npending |
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283 | IO::AIO::reinit |
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284 | |
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285 | $nfd = IO::AIO::get_fdlimit |
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286 | IO::AIO::min_fdlimit $nfd |
268 | |
287 | |
269 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
288 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
270 | IO::AIO::fadvise $fh, $offset, $len, $advice |
289 | IO::AIO::fadvise $fh, $offset, $len, $advice |
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290 | |
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291 | IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]] |
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292 | IO::AIO::munmap $scalar |
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293 | IO::AIO::mremap $scalar, $new_length, $flags[, $new_address] |
271 | IO::AIO::madvise $scalar, $offset, $length, $advice |
294 | IO::AIO::madvise $scalar, $offset, $length, $advice |
272 | IO::AIO::mprotect $scalar, $offset, $length, $protect |
295 | IO::AIO::mprotect $scalar, $offset, $length, $protect |
273 | IO::AIO::munlock $scalar, $offset = 0, $length = undef |
296 | IO::AIO::munlock $scalar, $offset = 0, $length = undef |
274 | IO::AIO::munlockall |
297 | IO::AIO::munlockall |
275 | |
298 | |
276 | =head2 AIO REQUEST FUNCTIONS |
299 | # stat extensions |
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300 | $counter = IO::AIO::st_gen |
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301 | $seconds = IO::AIO::st_atime, IO::AIO::st_mtime, IO::AIO::st_ctime, IO::AIO::st_btime |
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302 | ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtime |
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303 | $nanoseconds = IO::AIO::st_atimensec, IO::AIO::st_mtimensec, IO::AIO::st_ctimensec, IO::AIO::st_btimensec |
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304 | $seconds = IO::AIO::st_btimesec |
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305 | ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtimensec |
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306 | |
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307 | # very much unportable syscalls |
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308 | IO::AIO::accept4 $r_fh, $sockaddr, $sockaddr_len, $flags |
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309 | IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags |
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310 | IO::AIO::tee $r_fh, $w_fh, $length, $flags |
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311 | $actual_size = IO::AIO::pipesize $r_fh[, $new_size] |
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312 | ($rfh, $wfh) = IO::AIO::pipe2 [$flags] |
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313 | $fh = IO::AIO::memfd_create $pathname[, $flags] |
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314 | $fh = IO::AIO::eventfd [$initval, [$flags]] |
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315 | $fh = IO::AIO::timerfd_create $clockid[, $flags] |
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316 | ($cur_interval, $cur_value) = IO::AIO::timerfd_settime $fh, $flags, $new_interval, $nbw_value |
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317 | ($cur_interval, $cur_value) = IO::AIO::timerfd_gettime $fh |
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318 | |
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319 | =head2 API NOTES |
277 | |
320 | |
278 | All the C<aio_*> calls are more or less thin wrappers around the syscall |
321 | All the C<aio_*> calls are more or less thin wrappers around the syscall |
279 | with the same name (sans C<aio_>). The arguments are similar or identical, |
322 | with the same name (sans C<aio_>). The arguments are similar or identical, |
280 | and they all accept an additional (and optional) C<$callback> argument |
323 | and they all accept an additional (and optional) C<$callback> argument |
281 | which must be a code reference. This code reference will get called with |
324 | which must be a code reference. This code reference will be called after |
282 | the syscall return code (e.g. most syscalls return C<-1> on error, unlike |
325 | the syscall has been executed in an asynchronous fashion. The results |
283 | perl, which usually delivers "false") as its sole argument after the given |
326 | of the request will be passed as arguments to the callback (and, if an |
284 | syscall has been executed asynchronously. |
327 | error occured, in C<$!>) - for most requests the syscall return code (e.g. |
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328 | most syscalls return C<-1> on error, unlike perl, which usually delivers |
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329 | "false"). |
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330 | |
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331 | Some requests (such as C<aio_readdir>) pass the actual results and |
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332 | communicate failures by passing C<undef>. |
285 | |
333 | |
286 | All functions expecting a filehandle keep a copy of the filehandle |
334 | All functions expecting a filehandle keep a copy of the filehandle |
287 | internally until the request has finished. |
335 | internally until the request has finished. |
288 | |
336 | |
289 | All functions return request objects of type L<IO::AIO::REQ> that allow |
337 | All functions return request objects of type L<IO::AIO::REQ> that allow |
290 | further manipulation of those requests while they are in-flight. |
338 | further manipulation of those requests while they are in-flight. |
291 | |
339 | |
292 | The pathnames you pass to these routines I<must> be absolute and |
340 | The pathnames you pass to these routines I<should> be absolute. The |
293 | encoded as octets. The reason for the former is that at the time the |
341 | reason for this is that at the time the request is being executed, the |
294 | request is being executed, the current working directory could have |
342 | current working directory could have changed. Alternatively, you can |
295 | changed. Alternatively, you can make sure that you never change the |
343 | make sure that you never change the current working directory anywhere |
296 | current working directory anywhere in the program and then use relative |
344 | in the program and then use relative paths. You can also take advantage |
297 | paths. |
345 | of IO::AIOs working directory abstraction, that lets you specify paths |
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346 | relative to some previously-opened "working directory object" - see the |
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347 | description of the C<IO::AIO::WD> class later in this document. |
298 | |
348 | |
299 | To encode pathnames as octets, either make sure you either: a) always pass |
349 | To encode pathnames as octets, either make sure you either: a) always pass |
300 | in filenames you got from outside (command line, readdir etc.) without |
350 | in filenames you got from outside (command line, readdir etc.) without |
301 | tinkering, b) are ASCII or ISO 8859-1, c) use the Encode module and encode |
351 | tinkering, b) are in your native filesystem encoding, c) use the Encode |
302 | your pathnames to the locale (or other) encoding in effect in the user |
352 | module and encode your pathnames to the locale (or other) encoding in |
303 | environment, d) use Glib::filename_from_unicode on unicode filenames or e) |
353 | effect in the user environment, d) use Glib::filename_from_unicode on |
304 | use something else to ensure your scalar has the correct contents. |
354 | unicode filenames or e) use something else to ensure your scalar has the |
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355 | correct contents. |
305 | |
356 | |
306 | This works, btw. independent of the internal UTF-8 bit, which IO::AIO |
357 | This works, btw. independent of the internal UTF-8 bit, which IO::AIO |
307 | handles correctly whether it is set or not. |
358 | handles correctly whether it is set or not. |
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359 | |
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360 | =head2 AIO REQUEST FUNCTIONS |
308 | |
361 | |
309 | =over 4 |
362 | =over 4 |
310 | |
363 | |
311 | =item $prev_pri = aioreq_pri [$pri] |
364 | =item $prev_pri = aioreq_pri [$pri] |
312 | |
365 | |
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342 | |
395 | |
343 | |
396 | |
344 | =item aio_open $pathname, $flags, $mode, $callback->($fh) |
397 | =item aio_open $pathname, $flags, $mode, $callback->($fh) |
345 | |
398 | |
346 | Asynchronously open or create a file and call the callback with a newly |
399 | Asynchronously open or create a file and call the callback with a newly |
347 | created filehandle for the file. |
400 | created filehandle for the file (or C<undef> in case of an error). |
348 | |
401 | |
349 | The pathname passed to C<aio_open> must be absolute. See API NOTES, above, |
402 | The pathname passed to C<aio_open> must be absolute. See API NOTES, above, |
350 | for an explanation. |
403 | for an explanation. |
351 | |
404 | |
352 | The C<$flags> argument is a bitmask. See the C<Fcntl> module for a |
405 | The C<$flags> argument is a bitmask. See the C<Fcntl> module for a |
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368 | } else { |
421 | } else { |
369 | die "open failed: $!\n"; |
422 | die "open failed: $!\n"; |
370 | } |
423 | } |
371 | }; |
424 | }; |
372 | |
425 | |
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426 | In addition to all the common open modes/flags (C<O_RDONLY>, C<O_WRONLY>, |
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427 | C<O_RDWR>, C<O_CREAT>, C<O_TRUNC>, C<O_EXCL> and C<O_APPEND>), the |
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428 | following POSIX and non-POSIX constants are available (missing ones on |
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429 | your system are, as usual, C<0>): |
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430 | |
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431 | C<O_ASYNC>, C<O_DIRECT>, C<O_NOATIME>, C<O_CLOEXEC>, C<O_NOCTTY>, C<O_NOFOLLOW>, |
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432 | C<O_NONBLOCK>, C<O_EXEC>, C<O_SEARCH>, C<O_DIRECTORY>, C<O_DSYNC>, |
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433 | C<O_RSYNC>, C<O_SYNC>, C<O_PATH>, C<O_TMPFILE>, C<O_TTY_INIT> and C<O_ACCMODE>. |
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434 | |
373 | |
435 | |
374 | =item aio_close $fh, $callback->($status) |
436 | =item aio_close $fh, $callback->($status) |
375 | |
437 | |
376 | Asynchronously close a file and call the callback with the result |
438 | Asynchronously close a file and call the callback with the result |
377 | code. |
439 | code. |
… | |
… | |
386 | Or in other words: the file descriptor will be closed, but it will not be |
448 | Or in other words: the file descriptor will be closed, but it will not be |
387 | free for reuse until the perl filehandle is closed. |
449 | free for reuse until the perl filehandle is closed. |
388 | |
450 | |
389 | =cut |
451 | =cut |
390 | |
452 | |
|
|
453 | =item aio_seek $fh, $offset, $whence, $callback->($offs) |
|
|
454 | |
|
|
455 | Seeks the filehandle to the new C<$offset>, similarly to perl's |
|
|
456 | C<sysseek>. The C<$whence> can use the traditional values (C<0> for |
|
|
457 | C<IO::AIO::SEEK_SET>, C<1> for C<IO::AIO::SEEK_CUR> or C<2> for |
|
|
458 | C<IO::AIO::SEEK_END>). |
|
|
459 | |
|
|
460 | The resulting absolute offset will be passed to the callback, or C<-1> in |
|
|
461 | case of an error. |
|
|
462 | |
|
|
463 | In theory, the C<$whence> constants could be different than the |
|
|
464 | corresponding values from L<Fcntl>, but perl guarantees they are the same, |
|
|
465 | so don't panic. |
|
|
466 | |
|
|
467 | As a GNU/Linux (and maybe Solaris) extension, also the constants |
|
|
468 | C<IO::AIO::SEEK_DATA> and C<IO::AIO::SEEK_HOLE> are available, if they |
|
|
469 | could be found. No guarantees about suitability for use in C<aio_seek> or |
|
|
470 | Perl's C<sysseek> can be made though, although I would naively assume they |
|
|
471 | "just work". |
|
|
472 | |
391 | =item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
473 | =item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
392 | |
474 | |
393 | =item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
475 | =item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
394 | |
476 | |
395 | Reads or writes C<$length> bytes from or to the specified C<$fh> and |
477 | Reads or writes C<$length> bytes from or to the specified C<$fh> and |
396 | C<$offset> into the scalar given by C<$data> and offset C<$dataoffset> |
478 | C<$offset> into the scalar given by C<$data> and offset C<$dataoffset> and |
397 | and calls the callback without the actual number of bytes read (or -1 on |
479 | calls the callback with the actual number of bytes transferred (or -1 on |
398 | error, just like the syscall). |
480 | error, just like the syscall). |
399 | |
481 | |
400 | C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to |
482 | C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to |
401 | offset plus the actual number of bytes read. |
483 | offset plus the actual number of bytes read. |
402 | |
484 | |
… | |
… | |
427 | |
509 | |
428 | Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts |
510 | Tries to copy C<$length> bytes from C<$in_fh> to C<$out_fh>. It starts |
429 | reading at byte offset C<$in_offset>, and starts writing at the current |
511 | reading at byte offset C<$in_offset>, and starts writing at the current |
430 | file offset of C<$out_fh>. Because of that, it is not safe to issue more |
512 | file offset of C<$out_fh>. Because of that, it is not safe to issue more |
431 | than one C<aio_sendfile> per C<$out_fh>, as they will interfere with each |
513 | than one C<aio_sendfile> per C<$out_fh>, as they will interfere with each |
432 | other. |
514 | other. The same C<$in_fh> works fine though, as this function does not |
|
|
515 | move or use the file offset of C<$in_fh>. |
433 | |
516 | |
434 | Please note that C<aio_sendfile> can read more bytes from C<$in_fh> than |
517 | Please note that C<aio_sendfile> can read more bytes from C<$in_fh> than |
435 | are written, and there is no way to find out how many bytes have been read |
518 | are written, and there is no way to find out how many more bytes have been |
436 | from C<aio_sendfile> alone, as C<aio_sendfile> only provides the number of |
519 | read from C<aio_sendfile> alone, as C<aio_sendfile> only provides the |
437 | bytes written to C<$out_fh>. Only if the result value equals C<$length> |
520 | number of bytes written to C<$out_fh>. Only if the result value equals |
438 | one can assume that C<$length> bytes have been read. |
521 | C<$length> one can assume that C<$length> bytes have been read. |
439 | |
522 | |
440 | Unlike with other C<aio_> functions, it makes a lot of sense to use |
523 | Unlike with other C<aio_> functions, it makes a lot of sense to use |
441 | C<aio_sendfile> on non-blocking sockets, as long as one end (typically |
524 | C<aio_sendfile> on non-blocking sockets, as long as one end (typically |
442 | the C<$in_fh>) is a file - the file I/O will then be asynchronous, while |
525 | the C<$in_fh>) is a file - the file I/O will then be asynchronous, while |
443 | the socket I/O will be non-blocking. Note, however, that you can run into |
526 | the socket I/O will be non-blocking. Note, however, that you can run |
444 | a trap where C<aio_sendfile> reads some data with readahead, then fails |
527 | into a trap where C<aio_sendfile> reads some data with readahead, then |
445 | to write all data, and when the socket is ready the next time, the data |
528 | fails to write all data, and when the socket is ready the next time, the |
446 | in the cache is already lost, forcing C<aio_sendfile> to again hit the |
529 | data in the cache is already lost, forcing C<aio_sendfile> to again hit |
447 | disk. Explicit C<aio_read> + C<aio_write> let's you control resource usage |
530 | the disk. Explicit C<aio_read> + C<aio_write> let's you better control |
448 | much better. |
531 | resource usage. |
449 | |
532 | |
450 | This call tries to make use of a native C<sendfile> syscall to provide |
533 | This call tries to make use of a native C<sendfile>-like syscall to |
451 | zero-copy operation. For this to work, C<$out_fh> should refer to a |
534 | provide zero-copy operation. For this to work, C<$out_fh> should refer to |
452 | socket, and C<$in_fh> should refer to an mmap'able file. |
535 | a socket, and C<$in_fh> should refer to an mmap'able file. |
453 | |
536 | |
454 | If a native sendfile cannot be found or it fails with C<ENOSYS>, |
537 | If a native sendfile cannot be found or it fails with C<ENOSYS>, |
455 | C<ENOTSUP>, C<EOPNOTSUPP>, C<EAFNOSUPPORT>, C<EPROTOTYPE> or C<ENOTSOCK>, |
538 | C<EINVAL>, C<ENOTSUP>, C<EOPNOTSUPP>, C<EAFNOSUPPORT>, C<EPROTOTYPE> or |
456 | it will be emulated, so you can call C<aio_sendfile> on any type of |
539 | C<ENOTSOCK>, it will be emulated, so you can call C<aio_sendfile> on any |
457 | filehandle regardless of the limitations of the operating system. |
540 | type of filehandle regardless of the limitations of the operating system. |
|
|
541 | |
|
|
542 | As native sendfile syscalls (as practically any non-POSIX interface hacked |
|
|
543 | together in a hurry to improve benchmark numbers) tend to be rather buggy |
|
|
544 | on many systems, this implementation tries to work around some known bugs |
|
|
545 | in Linux and FreeBSD kernels (probably others, too), but that might fail, |
|
|
546 | so you really really should check the return value of C<aio_sendfile> - |
|
|
547 | fewer bytes than expected might have been transferred. |
458 | |
548 | |
459 | |
549 | |
460 | =item aio_readahead $fh,$offset,$length, $callback->($retval) |
550 | =item aio_readahead $fh,$offset,$length, $callback->($retval) |
461 | |
551 | |
462 | C<aio_readahead> populates the page cache with data from a file so that |
552 | C<aio_readahead> populates the page cache with data from a file so that |
… | |
… | |
466 | whole pages, so that offset is effectively rounded down to a page boundary |
556 | whole pages, so that offset is effectively rounded down to a page boundary |
467 | and bytes are read up to the next page boundary greater than or equal to |
557 | and bytes are read up to the next page boundary greater than or equal to |
468 | (off-set+length). C<aio_readahead> does not read beyond the end of the |
558 | (off-set+length). C<aio_readahead> does not read beyond the end of the |
469 | file. The current file offset of the file is left unchanged. |
559 | file. The current file offset of the file is left unchanged. |
470 | |
560 | |
471 | If that syscall doesn't exist (likely if your OS isn't Linux) it will be |
561 | If that syscall doesn't exist (likely if your kernel isn't Linux) it will |
472 | emulated by simply reading the data, which would have a similar effect. |
562 | be emulated by simply reading the data, which would have a similar effect. |
473 | |
563 | |
474 | |
564 | |
475 | =item aio_stat $fh_or_path, $callback->($status) |
565 | =item aio_stat $fh_or_path, $callback->($status) |
476 | |
566 | |
477 | =item aio_lstat $fh, $callback->($status) |
567 | =item aio_lstat $fh, $callback->($status) |
478 | |
568 | |
479 | Works like perl's C<stat> or C<lstat> in void context. The callback will |
569 | Works almost exactly like perl's C<stat> or C<lstat> in void context. The |
480 | be called after the stat and the results will be available using C<stat _> |
570 | callback will be called after the stat and the results will be available |
481 | or C<-s _> etc... |
571 | using C<stat _> or C<-s _> and other tests (with the exception of C<-B> |
|
|
572 | and C<-T>). |
482 | |
573 | |
483 | The pathname passed to C<aio_stat> must be absolute. See API NOTES, above, |
574 | The pathname passed to C<aio_stat> must be absolute. See API NOTES, above, |
484 | for an explanation. |
575 | for an explanation. |
485 | |
576 | |
486 | Currently, the stats are always 64-bit-stats, i.e. instead of returning an |
577 | Currently, the stats are always 64-bit-stats, i.e. instead of returning an |
… | |
… | |
493 | behaviour). |
584 | behaviour). |
494 | |
585 | |
495 | C<S_IFMT>, C<S_IFIFO>, C<S_IFCHR>, C<S_IFBLK>, C<S_IFLNK>, C<S_IFREG>, |
586 | C<S_IFMT>, C<S_IFIFO>, C<S_IFCHR>, C<S_IFBLK>, C<S_IFLNK>, C<S_IFREG>, |
496 | C<S_IFDIR>, C<S_IFWHT>, C<S_IFSOCK>, C<IO::AIO::major $dev_t>, |
587 | C<S_IFDIR>, C<S_IFWHT>, C<S_IFSOCK>, C<IO::AIO::major $dev_t>, |
497 | C<IO::AIO::minor $dev_t>, C<IO::AIO::makedev $major, $minor>. |
588 | C<IO::AIO::minor $dev_t>, C<IO::AIO::makedev $major, $minor>. |
|
|
589 | |
|
|
590 | To access higher resolution stat timestamps, see L<SUBSECOND STAT TIME |
|
|
591 | ACCESS>. |
498 | |
592 | |
499 | Example: Print the length of F</etc/passwd>: |
593 | Example: Print the length of F</etc/passwd>: |
500 | |
594 | |
501 | aio_stat "/etc/passwd", sub { |
595 | aio_stat "/etc/passwd", sub { |
502 | $_[0] and die "stat failed: $!"; |
596 | $_[0] and die "stat failed: $!"; |
… | |
… | |
546 | namemax => 255, |
640 | namemax => 255, |
547 | frsize => 1024, |
641 | frsize => 1024, |
548 | fsid => 1810 |
642 | fsid => 1810 |
549 | } |
643 | } |
550 | |
644 | |
551 | |
|
|
552 | =item aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
645 | =item aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
553 | |
646 | |
554 | Works like perl's C<utime> function (including the special case of $atime |
647 | Works like perl's C<utime> function (including the special case of $atime |
555 | and $mtime being undef). Fractional times are supported if the underlying |
648 | and $mtime being undef). Fractional times are supported if the underlying |
556 | syscalls support them. |
649 | syscalls support them. |
557 | |
650 | |
558 | When called with a pathname, uses utimes(2) if available, otherwise |
651 | When called with a pathname, uses utimensat(2) or utimes(2) if available, |
559 | utime(2). If called on a file descriptor, uses futimes(2) if available, |
652 | otherwise utime(2). If called on a file descriptor, uses futimens(2) |
560 | otherwise returns ENOSYS, so this is not portable. |
653 | or futimes(2) if available, otherwise returns ENOSYS, so this is not |
|
|
654 | portable. |
561 | |
655 | |
562 | Examples: |
656 | Examples: |
563 | |
657 | |
564 | # set atime and mtime to current time (basically touch(1)): |
658 | # set atime and mtime to current time (basically touch(1)): |
565 | aio_utime "path", undef, undef; |
659 | aio_utime "path", undef, undef; |
… | |
… | |
583 | =item aio_truncate $fh_or_path, $offset, $callback->($status) |
677 | =item aio_truncate $fh_or_path, $offset, $callback->($status) |
584 | |
678 | |
585 | Works like truncate(2) or ftruncate(2). |
679 | Works like truncate(2) or ftruncate(2). |
586 | |
680 | |
587 | |
681 | |
|
|
682 | =item aio_allocate $fh, $mode, $offset, $len, $callback->($status) |
|
|
683 | |
|
|
684 | Allocates or frees disk space according to the C<$mode> argument. See the |
|
|
685 | linux C<fallocate> documentation for details. |
|
|
686 | |
|
|
687 | C<$mode> is usually C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> to allocate |
|
|
688 | space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE | IO::AIO::FALLOC_FL_KEEP_SIZE>, |
|
|
689 | to deallocate a file range. |
|
|
690 | |
|
|
691 | IO::AIO also supports C<FALLOC_FL_COLLAPSE_RANGE>, to remove a range |
|
|
692 | (without leaving a hole), C<FALLOC_FL_ZERO_RANGE>, to zero a range, |
|
|
693 | C<FALLOC_FL_INSERT_RANGE> to insert a range and C<FALLOC_FL_UNSHARE_RANGE> |
|
|
694 | to unshare shared blocks (see your L<fallocate(2)> manpage). |
|
|
695 | |
|
|
696 | The file system block size used by C<fallocate> is presumably the |
|
|
697 | C<f_bsize> returned by C<statvfs>, but different filesystems and filetypes |
|
|
698 | can dictate other limitations. |
|
|
699 | |
|
|
700 | If C<fallocate> isn't available or cannot be emulated (currently no |
|
|
701 | emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>. |
|
|
702 | |
|
|
703 | |
588 | =item aio_chmod $fh_or_path, $mode, $callback->($status) |
704 | =item aio_chmod $fh_or_path, $mode, $callback->($status) |
589 | |
705 | |
590 | Works like perl's C<chmod> function. |
706 | Works like perl's C<chmod> function. |
591 | |
707 | |
592 | |
708 | |
… | |
… | |
594 | |
710 | |
595 | Asynchronously unlink (delete) a file and call the callback with the |
711 | Asynchronously unlink (delete) a file and call the callback with the |
596 | result code. |
712 | result code. |
597 | |
713 | |
598 | |
714 | |
599 | =item aio_mknod $path, $mode, $dev, $callback->($status) |
715 | =item aio_mknod $pathname, $mode, $dev, $callback->($status) |
600 | |
716 | |
601 | [EXPERIMENTAL] |
717 | [EXPERIMENTAL] |
602 | |
718 | |
603 | Asynchronously create a device node (or fifo). See mknod(2). |
719 | Asynchronously create a device node (or fifo). See mknod(2). |
604 | |
720 | |
605 | The only (POSIX-) portable way of calling this function is: |
721 | The only (POSIX-) portable way of calling this function is: |
606 | |
722 | |
607 | aio_mknod $path, IO::AIO::S_IFIFO | $mode, 0, sub { ... |
723 | aio_mknod $pathname, IO::AIO::S_IFIFO | $mode, 0, sub { ... |
608 | |
724 | |
609 | See C<aio_stat> for info about some potentially helpful extra constants |
725 | See C<aio_stat> for info about some potentially helpful extra constants |
610 | and functions. |
726 | and functions. |
611 | |
727 | |
612 | =item aio_link $srcpath, $dstpath, $callback->($status) |
728 | =item aio_link $srcpath, $dstpath, $callback->($status) |
… | |
… | |
619 | |
735 | |
620 | Asynchronously create a new symbolic link to the existing object at C<$srcpath> at |
736 | Asynchronously create a new symbolic link to the existing object at C<$srcpath> at |
621 | the path C<$dstpath> and call the callback with the result code. |
737 | the path C<$dstpath> and call the callback with the result code. |
622 | |
738 | |
623 | |
739 | |
624 | =item aio_readlink $path, $callback->($link) |
740 | =item aio_readlink $pathname, $callback->($link) |
625 | |
741 | |
626 | Asynchronously read the symlink specified by C<$path> and pass it to |
742 | Asynchronously read the symlink specified by C<$path> and pass it to |
627 | the callback. If an error occurs, nothing or undef gets passed to the |
743 | the callback. If an error occurs, nothing or undef gets passed to the |
628 | callback. |
744 | callback. |
629 | |
745 | |
630 | |
746 | |
|
|
747 | =item aio_realpath $pathname, $callback->($path) |
|
|
748 | |
|
|
749 | Asynchronously make the path absolute and resolve any symlinks in |
|
|
750 | C<$path>. The resulting path only consists of directories (same as |
|
|
751 | L<Cwd::realpath>). |
|
|
752 | |
|
|
753 | This request can be used to get the absolute path of the current working |
|
|
754 | directory by passing it a path of F<.> (a single dot). |
|
|
755 | |
|
|
756 | |
631 | =item aio_rename $srcpath, $dstpath, $callback->($status) |
757 | =item aio_rename $srcpath, $dstpath, $callback->($status) |
632 | |
758 | |
633 | Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as |
759 | Asynchronously rename the object at C<$srcpath> to C<$dstpath>, just as |
634 | rename(2) and call the callback with the result code. |
760 | rename(2) and call the callback with the result code. |
|
|
761 | |
|
|
762 | On systems that support the AIO::WD working directory abstraction |
|
|
763 | natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead |
|
|
764 | of failing, C<rename> is called on the absolute path of C<$wd>. |
|
|
765 | |
|
|
766 | |
|
|
767 | =item aio_rename2 $srcpath, $dstpath, $flags, $callback->($status) |
|
|
768 | |
|
|
769 | Basically a version of C<aio_rename> with an additional C<$flags> |
|
|
770 | argument. Calling this with C<$flags=0> is the same as calling |
|
|
771 | C<aio_rename>. |
|
|
772 | |
|
|
773 | Non-zero flags are currently only supported on GNU/Linux systems that |
|
|
774 | support renameat2. Other systems fail with C<ENOSYS> in this case. |
|
|
775 | |
|
|
776 | The following constants are available (missing ones are, as usual C<0>), |
|
|
777 | see renameat2(2) for details: |
|
|
778 | |
|
|
779 | C<IO::AIO::RENAME_NOREPLACE>, C<IO::AIO::RENAME_EXCHANGE> |
|
|
780 | and C<IO::AIO::RENAME_WHITEOUT>. |
635 | |
781 | |
636 | |
782 | |
637 | =item aio_mkdir $pathname, $mode, $callback->($status) |
783 | =item aio_mkdir $pathname, $mode, $callback->($status) |
638 | |
784 | |
639 | Asynchronously mkdir (create) a directory and call the callback with |
785 | Asynchronously mkdir (create) a directory and call the callback with |
… | |
… | |
644 | =item aio_rmdir $pathname, $callback->($status) |
790 | =item aio_rmdir $pathname, $callback->($status) |
645 | |
791 | |
646 | Asynchronously rmdir (delete) a directory and call the callback with the |
792 | Asynchronously rmdir (delete) a directory and call the callback with the |
647 | result code. |
793 | result code. |
648 | |
794 | |
|
|
795 | On systems that support the AIO::WD working directory abstraction |
|
|
796 | natively, the case C<[$wd, "."]> is specialcased - instead of failing, |
|
|
797 | C<rmdir> is called on the absolute path of C<$wd>. |
|
|
798 | |
649 | |
799 | |
650 | =item aio_readdir $pathname, $callback->($entries) |
800 | =item aio_readdir $pathname, $callback->($entries) |
651 | |
801 | |
652 | Unlike the POSIX call of the same name, C<aio_readdir> reads an entire |
802 | Unlike the POSIX call of the same name, C<aio_readdir> reads an entire |
653 | directory (i.e. opendir + readdir + closedir). The entries will not be |
803 | directory (i.e. opendir + readdir + closedir). The entries will not be |
… | |
… | |
657 | array-ref with the filenames. |
807 | array-ref with the filenames. |
658 | |
808 | |
659 | |
809 | |
660 | =item aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
810 | =item aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
661 | |
811 | |
662 | Quite similar to C<aio_readdir>, but the C<$flags> argument allows to tune |
812 | Quite similar to C<aio_readdir>, but the C<$flags> argument allows one to |
663 | behaviour and output format. In case of an error, C<$entries> will be |
813 | tune behaviour and output format. In case of an error, C<$entries> will be |
664 | C<undef>. |
814 | C<undef>. |
665 | |
815 | |
666 | The flags are a combination of the following constants, ORed together (the |
816 | The flags are a combination of the following constants, ORed together (the |
667 | flags will also be passed to the callback, possibly modified): |
817 | flags will also be passed to the callback, possibly modified): |
668 | |
818 | |
669 | =over 4 |
819 | =over 4 |
670 | |
820 | |
671 | =item IO::AIO::READDIR_DENTS |
821 | =item IO::AIO::READDIR_DENTS |
672 | |
822 | |
673 | When this flag is off, then the callback gets an arrayref with of names |
823 | Normally the callback gets an arrayref consisting of names only (as |
674 | only (as with C<aio_readdir>), otherwise it gets an arrayref with |
824 | with C<aio_readdir>). If this flag is set, then the callback gets an |
675 | C<[$name, $type, $inode]> arrayrefs, each describing a single directory |
825 | arrayref with C<[$name, $type, $inode]> arrayrefs, each describing a |
676 | entry in more detail. |
826 | single directory entry in more detail: |
677 | |
827 | |
678 | C<$name> is the name of the entry. |
828 | C<$name> is the name of the entry. |
679 | |
829 | |
680 | C<$type> is one of the C<IO::AIO::DT_xxx> constants: |
830 | C<$type> is one of the C<IO::AIO::DT_xxx> constants: |
681 | |
831 | |
682 | C<IO::AIO::DT_UNKNOWN>, C<IO::AIO::DT_FIFO>, C<IO::AIO::DT_CHR>, C<IO::AIO::DT_DIR>, |
832 | C<IO::AIO::DT_UNKNOWN>, C<IO::AIO::DT_FIFO>, C<IO::AIO::DT_CHR>, C<IO::AIO::DT_DIR>, |
683 | C<IO::AIO::DT_BLK>, C<IO::AIO::DT_REG>, C<IO::AIO::DT_LNK>, C<IO::AIO::DT_SOCK>, |
833 | C<IO::AIO::DT_BLK>, C<IO::AIO::DT_REG>, C<IO::AIO::DT_LNK>, C<IO::AIO::DT_SOCK>, |
684 | C<IO::AIO::DT_WHT>. |
834 | C<IO::AIO::DT_WHT>. |
685 | |
835 | |
686 | C<IO::AIO::DT_UNKNOWN> means just that: readdir does not know. If you need to |
836 | C<IO::AIO::DT_UNKNOWN> means just that: readdir does not know. If you need |
687 | know, you have to run stat yourself. Also, for speed reasons, the C<$type> |
837 | to know, you have to run stat yourself. Also, for speed/memory reasons, |
688 | scalars are read-only: you can not modify them. |
838 | the C<$type> scalars are read-only: you must not modify them. |
689 | |
839 | |
690 | C<$inode> is the inode number (which might not be exact on systems with 64 |
840 | C<$inode> is the inode number (which might not be exact on systems with 64 |
691 | bit inode numbers and 32 bit perls). This field has unspecified content on |
841 | bit inode numbers and 32 bit perls). This field has unspecified content on |
692 | systems that do not deliver the inode information. |
842 | systems that do not deliver the inode information. |
693 | |
843 | |
694 | =item IO::AIO::READDIR_DIRS_FIRST |
844 | =item IO::AIO::READDIR_DIRS_FIRST |
695 | |
845 | |
696 | When this flag is set, then the names will be returned in an order where |
846 | When this flag is set, then the names will be returned in an order where |
697 | likely directories come first. This is useful when you need to quickly |
847 | likely directories come first, in optimal stat order. This is useful when |
698 | find directories, or you want to find all directories while avoiding to |
848 | you need to quickly find directories, or you want to find all directories |
699 | stat() each entry. |
849 | while avoiding to stat() each entry. |
700 | |
850 | |
701 | If the system returns type information in readdir, then this is used |
851 | If the system returns type information in readdir, then this is used |
702 | to find directories directly. Otherwise, likely directories are files |
852 | to find directories directly. Otherwise, likely directories are names |
703 | beginning with ".", or otherwise files with no dots, of which files with |
853 | beginning with ".", or otherwise names with no dots, of which names with |
704 | short names are tried first. |
854 | short names are tried first. |
705 | |
855 | |
706 | =item IO::AIO::READDIR_STAT_ORDER |
856 | =item IO::AIO::READDIR_STAT_ORDER |
707 | |
857 | |
708 | When this flag is set, then the names will be returned in an order |
858 | When this flag is set, then the names will be returned in an order |
709 | suitable for stat()'ing each one. That is, when you plan to stat() |
859 | suitable for stat()'ing each one. That is, when you plan to stat() most or |
710 | all files in the given directory, then the returned order will likely |
860 | all files in the given directory, then the returned order will likely be |
711 | be fastest. |
861 | faster. |
712 | |
862 | |
713 | If both this flag and C<IO::AIO::READDIR_DIRS_FIRST> are specified, then |
863 | If both this flag and C<IO::AIO::READDIR_DIRS_FIRST> are specified, |
714 | the likely dirs come first, resulting in a less optimal stat order. |
864 | then the likely dirs come first, resulting in a less optimal stat order |
|
|
865 | for stat'ing all entries, but likely a more optimal order for finding |
|
|
866 | subdirectories. |
715 | |
867 | |
716 | =item IO::AIO::READDIR_FOUND_UNKNOWN |
868 | =item IO::AIO::READDIR_FOUND_UNKNOWN |
717 | |
869 | |
718 | This flag should not be set when calling C<aio_readdirx>. Instead, it |
870 | This flag should not be set when calling C<aio_readdirx>. Instead, it |
719 | is being set by C<aio_readdirx>, when any of the C<$type>'s found were |
871 | is being set by C<aio_readdirx>, when any of the C<$type>'s found were |
720 | C<IO::AIO::DT_UNKNOWN>. The absense of this flag therefore indicates that all |
872 | C<IO::AIO::DT_UNKNOWN>. The absence of this flag therefore indicates that all |
721 | C<$type>'s are known, which can be used to speed up some algorithms. |
873 | C<$type>'s are known, which can be used to speed up some algorithms. |
722 | |
874 | |
723 | =back |
875 | =back |
724 | |
876 | |
725 | |
877 | |
|
|
878 | =item aio_slurp $pathname, $offset, $length, $data, $callback->($status) |
|
|
879 | |
|
|
880 | Opens, reads and closes the given file. The data is put into C<$data>, |
|
|
881 | which is resized as required. |
|
|
882 | |
|
|
883 | If C<$offset> is negative, then it is counted from the end of the file. |
|
|
884 | |
|
|
885 | If C<$length> is zero, then the remaining length of the file is |
|
|
886 | used. Also, in this case, the same limitations to modifying C<$data> apply |
|
|
887 | as when IO::AIO::mmap is used, i.e. it must only be modified in-place |
|
|
888 | with C<substr>. If the size of the file is known, specifying a non-zero |
|
|
889 | C<$length> results in a performance advantage. |
|
|
890 | |
|
|
891 | This request is similar to the older C<aio_load> request, but since it is |
|
|
892 | a single request, it might be more efficient to use. |
|
|
893 | |
|
|
894 | Example: load F</etc/passwd> into C<$passwd>. |
|
|
895 | |
|
|
896 | my $passwd; |
|
|
897 | aio_slurp "/etc/passwd", 0, 0, $passwd, sub { |
|
|
898 | $_[0] >= 0 |
|
|
899 | or die "/etc/passwd: $!\n"; |
|
|
900 | |
|
|
901 | printf "/etc/passwd is %d bytes long, and contains:\n", length $passwd; |
|
|
902 | print $passwd; |
|
|
903 | }; |
|
|
904 | IO::AIO::flush; |
|
|
905 | |
|
|
906 | |
726 | =item aio_load $path, $data, $callback->($status) |
907 | =item aio_load $pathname, $data, $callback->($status) |
727 | |
908 | |
728 | This is a composite request that tries to fully load the given file into |
909 | This is a composite request that tries to fully load the given file into |
729 | memory. Status is the same as with aio_read. |
910 | memory. Status is the same as with aio_read. |
|
|
911 | |
|
|
912 | Using C<aio_slurp> might be more efficient, as it is a single request. |
730 | |
913 | |
731 | =cut |
914 | =cut |
732 | |
915 | |
733 | sub aio_load($$;$) { |
916 | sub aio_load($$;$) { |
734 | my ($path, undef, $cb) = @_; |
917 | my ($path, undef, $cb) = @_; |
… | |
… | |
754 | =item aio_copy $srcpath, $dstpath, $callback->($status) |
937 | =item aio_copy $srcpath, $dstpath, $callback->($status) |
755 | |
938 | |
756 | Try to copy the I<file> (directories not supported as either source or |
939 | Try to copy the I<file> (directories not supported as either source or |
757 | destination) from C<$srcpath> to C<$dstpath> and call the callback with |
940 | destination) from C<$srcpath> to C<$dstpath> and call the callback with |
758 | a status of C<0> (ok) or C<-1> (error, see C<$!>). |
941 | a status of C<0> (ok) or C<-1> (error, see C<$!>). |
|
|
942 | |
|
|
943 | Existing destination files will be truncated. |
759 | |
944 | |
760 | This is a composite request that creates the destination file with |
945 | This is a composite request that creates the destination file with |
761 | mode 0200 and copies the contents of the source file into it using |
946 | mode 0200 and copies the contents of the source file into it using |
762 | C<aio_sendfile>, followed by restoring atime, mtime, access mode and |
947 | C<aio_sendfile>, followed by restoring atime, mtime, access mode and |
763 | uid/gid, in that order. |
948 | uid/gid, in that order. |
… | |
… | |
853 | if ($_[0] && $! == EXDEV) { |
1038 | if ($_[0] && $! == EXDEV) { |
854 | aioreq_pri $pri; |
1039 | aioreq_pri $pri; |
855 | add $grp aio_copy $src, $dst, sub { |
1040 | add $grp aio_copy $src, $dst, sub { |
856 | $grp->result ($_[0]); |
1041 | $grp->result ($_[0]); |
857 | |
1042 | |
858 | if (!$_[0]) { |
1043 | unless ($_[0]) { |
859 | aioreq_pri $pri; |
1044 | aioreq_pri $pri; |
860 | add $grp aio_unlink $src; |
1045 | add $grp aio_unlink $src; |
861 | } |
1046 | } |
862 | }; |
1047 | }; |
863 | } else { |
1048 | } else { |
… | |
… | |
866 | }; |
1051 | }; |
867 | |
1052 | |
868 | $grp |
1053 | $grp |
869 | } |
1054 | } |
870 | |
1055 | |
871 | =item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs) |
1056 | =item aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs) |
872 | |
1057 | |
873 | Scans a directory (similar to C<aio_readdir>) but additionally tries to |
1058 | Scans a directory (similar to C<aio_readdir>) but additionally tries to |
874 | efficiently separate the entries of directory C<$path> into two sets of |
1059 | efficiently separate the entries of directory C<$path> into two sets of |
875 | names, directories you can recurse into (directories), and ones you cannot |
1060 | names, directories you can recurse into (directories), and ones you cannot |
876 | recurse into (everything else, including symlinks to directories). |
1061 | recurse into (everything else, including symlinks to directories). |
877 | |
1062 | |
878 | C<aio_scandir> is a composite request that creates of many sub requests_ |
1063 | C<aio_scandir> is a composite request that generates many sub requests. |
879 | C<$maxreq> specifies the maximum number of outstanding aio requests that |
1064 | C<$maxreq> specifies the maximum number of outstanding aio requests that |
880 | this function generates. If it is C<< <= 0 >>, then a suitable default |
1065 | this function generates. If it is C<< <= 0 >>, then a suitable default |
881 | will be chosen (currently 4). |
1066 | will be chosen (currently 4). |
882 | |
1067 | |
883 | On error, the callback is called without arguments, otherwise it receives |
1068 | On error, the callback is called without arguments, otherwise it receives |
… | |
… | |
907 | Then entries will be sorted into likely directories a non-initial dot |
1092 | Then entries will be sorted into likely directories a non-initial dot |
908 | currently) and likely non-directories (see C<aio_readdirx>). Then every |
1093 | currently) and likely non-directories (see C<aio_readdirx>). Then every |
909 | entry plus an appended C</.> will be C<stat>'ed, likely directories first, |
1094 | entry plus an appended C</.> will be C<stat>'ed, likely directories first, |
910 | in order of their inode numbers. If that succeeds, it assumes that the |
1095 | in order of their inode numbers. If that succeeds, it assumes that the |
911 | entry is a directory or a symlink to directory (which will be checked |
1096 | entry is a directory or a symlink to directory (which will be checked |
912 | seperately). This is often faster than stat'ing the entry itself because |
1097 | separately). This is often faster than stat'ing the entry itself because |
913 | filesystems might detect the type of the entry without reading the inode |
1098 | filesystems might detect the type of the entry without reading the inode |
914 | data (e.g. ext2fs filetype feature), even on systems that cannot return |
1099 | data (e.g. ext2fs filetype feature), even on systems that cannot return |
915 | the filetype information on readdir. |
1100 | the filetype information on readdir. |
916 | |
1101 | |
917 | If the known number of directories (link count - 2) has been reached, the |
1102 | If the known number of directories (link count - 2) has been reached, the |
… | |
… | |
933 | |
1118 | |
934 | my $grp = aio_group $cb; |
1119 | my $grp = aio_group $cb; |
935 | |
1120 | |
936 | $maxreq = 4 if $maxreq <= 0; |
1121 | $maxreq = 4 if $maxreq <= 0; |
937 | |
1122 | |
938 | # stat once |
1123 | # get a wd object |
939 | aioreq_pri $pri; |
1124 | aioreq_pri $pri; |
940 | add $grp aio_stat $path, sub { |
1125 | add $grp aio_wd $path, sub { |
|
|
1126 | $_[0] |
941 | return $grp->result () if $_[0]; |
1127 | or return $grp->result (); |
942 | my $now = time; |
|
|
943 | my $hash1 = join ":", (stat _)[0,1,3,7,9]; |
|
|
944 | |
1128 | |
945 | # read the directory entries |
1129 | my $wd = [shift, "."]; |
|
|
1130 | |
|
|
1131 | # stat once |
946 | aioreq_pri $pri; |
1132 | aioreq_pri $pri; |
947 | add $grp aio_readdirx $path, READDIR_DIRS_FIRST, sub { |
1133 | add $grp aio_stat $wd, sub { |
948 | my $entries = shift |
|
|
949 | or return $grp->result (); |
1134 | return $grp->result () if $_[0]; |
|
|
1135 | my $now = time; |
|
|
1136 | my $hash1 = join ":", (stat _)[0,1,3,7,9]; |
|
|
1137 | my $rdxflags = READDIR_DIRS_FIRST; |
950 | |
1138 | |
951 | # stat the dir another time |
1139 | if ((stat _)[3] < 2) { |
|
|
1140 | # at least one non-POSIX filesystem exists |
|
|
1141 | # that returns useful DT_type values: btrfs, |
|
|
1142 | # so optimise for this here by requesting dents |
|
|
1143 | $rdxflags |= READDIR_DENTS; |
|
|
1144 | } |
|
|
1145 | |
|
|
1146 | # read the directory entries |
952 | aioreq_pri $pri; |
1147 | aioreq_pri $pri; |
953 | add $grp aio_stat $path, sub { |
1148 | add $grp aio_readdirx $wd, $rdxflags, sub { |
954 | my $hash2 = join ":", (stat _)[0,1,3,7,9]; |
1149 | my ($entries, $flags) = @_ |
|
|
1150 | or return $grp->result (); |
955 | |
1151 | |
|
|
1152 | if ($rdxflags & READDIR_DENTS) { |
|
|
1153 | # if we requested type values, see if we can use them directly. |
|
|
1154 | |
|
|
1155 | # if there were any DT_UNKNOWN entries then we assume we |
|
|
1156 | # don't know. alternatively, we could assume that if we get |
|
|
1157 | # one DT_DIR, then all directories are indeed marked with |
|
|
1158 | # DT_DIR, but this seems not required for btrfs, and this |
|
|
1159 | # is basically the "btrfs can't get it's act together" code |
|
|
1160 | # branch. |
|
|
1161 | unless ($flags & READDIR_FOUND_UNKNOWN) { |
|
|
1162 | # now we have valid DT_ information for all entries, |
|
|
1163 | # so use it as an optimisation without further stat's. |
|
|
1164 | # they must also all be at the beginning of @$entries |
|
|
1165 | # by now. |
|
|
1166 | |
956 | my $ndirs; |
1167 | my $dirs; |
957 | |
1168 | |
958 | # take the slow route if anything looks fishy |
|
|
959 | if ($hash1 ne $hash2 or (stat _)[9] == $now) { |
|
|
960 | $ndirs = -1; |
|
|
961 | } else { |
|
|
962 | # if nlink == 2, we are finished |
|
|
963 | # for non-posix-fs's, we rely on nlink < 2 |
|
|
964 | $ndirs = (stat _)[3] - 2 |
|
|
965 | or return $grp->result ([], $entries); |
|
|
966 | } |
|
|
967 | |
|
|
968 | my (@dirs, @nondirs); |
|
|
969 | |
|
|
970 | my $statgrp = add $grp aio_group sub { |
|
|
971 | $grp->result (\@dirs, \@nondirs); |
|
|
972 | }; |
|
|
973 | |
|
|
974 | limit $statgrp $maxreq; |
|
|
975 | feed $statgrp sub { |
|
|
976 | return unless @$entries; |
|
|
977 | my $entry = shift @$entries; |
|
|
978 | |
|
|
979 | aioreq_pri $pri; |
|
|
980 | add $statgrp aio_stat "$path/$entry/.", sub { |
|
|
981 | if ($_[0] < 0) { |
1169 | if (@$entries) { |
982 | push @nondirs, $entry; |
1170 | for (0 .. $#$entries) { |
983 | } else { |
1171 | if ($entries->[$_][1] != DT_DIR) { |
984 | # need to check for real directory |
1172 | # splice out directories |
985 | aioreq_pri $pri; |
1173 | $dirs = [splice @$entries, 0, $_]; |
986 | add $statgrp aio_lstat "$path/$entry", sub { |
|
|
987 | if (-d _) { |
|
|
988 | push @dirs, $entry; |
|
|
989 | |
|
|
990 | unless (--$ndirs) { |
|
|
991 | push @nondirs, @$entries; |
|
|
992 | feed $statgrp; |
|
|
993 | } |
1174 | last; |
994 | } else { |
|
|
995 | push @nondirs, $entry; |
|
|
996 | } |
1175 | } |
997 | } |
1176 | } |
|
|
1177 | |
|
|
1178 | # if we didn't find any non-dir, then all entries are dirs |
|
|
1179 | unless ($dirs) { |
|
|
1180 | ($dirs, $entries) = ($entries, []); |
|
|
1181 | } |
|
|
1182 | } else { |
|
|
1183 | # directory is empty, so there are no sbdirs |
|
|
1184 | $dirs = []; |
998 | } |
1185 | } |
|
|
1186 | |
|
|
1187 | # either splice'd the directories out or the dir was empty. |
|
|
1188 | # convert dents to filenames |
|
|
1189 | $_ = $_->[0] for @$dirs; |
|
|
1190 | $_ = $_->[0] for @$entries; |
|
|
1191 | |
|
|
1192 | return $grp->result ($dirs, $entries); |
|
|
1193 | } |
|
|
1194 | |
|
|
1195 | # cannot use, so return to our old ways |
|
|
1196 | # by pretending we only scanned for names. |
|
|
1197 | $_ = $_->[0] for @$entries; |
|
|
1198 | } |
|
|
1199 | |
|
|
1200 | # stat the dir another time |
|
|
1201 | aioreq_pri $pri; |
|
|
1202 | add $grp aio_stat $wd, sub { |
|
|
1203 | my $hash2 = join ":", (stat _)[0,1,3,7,9]; |
|
|
1204 | |
|
|
1205 | my $ndirs; |
|
|
1206 | |
|
|
1207 | # take the slow route if anything looks fishy |
|
|
1208 | if ($hash1 ne $hash2 or (stat _)[9] == $now) { |
|
|
1209 | $ndirs = -1; |
|
|
1210 | } else { |
|
|
1211 | # if nlink == 2, we are finished |
|
|
1212 | # for non-posix-fs's, we rely on nlink < 2 |
|
|
1213 | $ndirs = (stat _)[3] - 2 |
|
|
1214 | or return $grp->result ([], $entries); |
|
|
1215 | } |
|
|
1216 | |
|
|
1217 | my (@dirs, @nondirs); |
|
|
1218 | |
|
|
1219 | my $statgrp = add $grp aio_group sub { |
|
|
1220 | $grp->result (\@dirs, \@nondirs); |
|
|
1221 | }; |
|
|
1222 | |
|
|
1223 | limit $statgrp $maxreq; |
|
|
1224 | feed $statgrp sub { |
|
|
1225 | return unless @$entries; |
|
|
1226 | my $entry = shift @$entries; |
|
|
1227 | |
|
|
1228 | aioreq_pri $pri; |
|
|
1229 | $wd->[1] = "$entry/."; |
|
|
1230 | add $statgrp aio_stat $wd, sub { |
|
|
1231 | if ($_[0] < 0) { |
|
|
1232 | push @nondirs, $entry; |
|
|
1233 | } else { |
|
|
1234 | # need to check for real directory |
|
|
1235 | aioreq_pri $pri; |
|
|
1236 | $wd->[1] = $entry; |
|
|
1237 | add $statgrp aio_lstat $wd, sub { |
|
|
1238 | if (-d _) { |
|
|
1239 | push @dirs, $entry; |
|
|
1240 | |
|
|
1241 | unless (--$ndirs) { |
|
|
1242 | push @nondirs, @$entries; |
|
|
1243 | feed $statgrp; |
|
|
1244 | } |
|
|
1245 | } else { |
|
|
1246 | push @nondirs, $entry; |
|
|
1247 | } |
|
|
1248 | } |
|
|
1249 | } |
|
|
1250 | }; |
999 | }; |
1251 | }; |
1000 | }; |
1252 | }; |
1001 | }; |
1253 | }; |
1002 | }; |
1254 | }; |
1003 | }; |
1255 | }; |
1004 | |
1256 | |
1005 | $grp |
1257 | $grp |
1006 | } |
1258 | } |
1007 | |
1259 | |
1008 | =item aio_rmtree $path, $callback->($status) |
1260 | =item aio_rmtree $pathname, $callback->($status) |
1009 | |
1261 | |
1010 | Delete a directory tree starting (and including) C<$path>, return the |
1262 | Delete a directory tree starting (and including) C<$path>, return the |
1011 | status of the final C<rmdir> only. This is a composite request that |
1263 | status of the final C<rmdir> only. This is a composite request that |
1012 | uses C<aio_scandir> to recurse into and rmdir directories, and unlink |
1264 | uses C<aio_scandir> to recurse into and rmdir directories, and unlink |
1013 | everything else. |
1265 | everything else. |
1014 | |
1266 | |
1015 | =cut |
1267 | =cut |
1016 | |
1268 | |
… | |
… | |
1038 | }; |
1290 | }; |
1039 | |
1291 | |
1040 | $grp |
1292 | $grp |
1041 | } |
1293 | } |
1042 | |
1294 | |
|
|
1295 | =item aio_fcntl $fh, $cmd, $arg, $callback->($status) |
|
|
1296 | |
|
|
1297 | =item aio_ioctl $fh, $request, $buf, $callback->($status) |
|
|
1298 | |
|
|
1299 | These work just like the C<fcntl> and C<ioctl> built-in functions, except |
|
|
1300 | they execute asynchronously and pass the return value to the callback. |
|
|
1301 | |
|
|
1302 | Both calls can be used for a lot of things, some of which make more sense |
|
|
1303 | to run asynchronously in their own thread, while some others make less |
|
|
1304 | sense. For example, calls that block waiting for external events, such |
|
|
1305 | as locking, will also lock down an I/O thread while it is waiting, which |
|
|
1306 | can deadlock the whole I/O system. At the same time, there might be no |
|
|
1307 | alternative to using a thread to wait. |
|
|
1308 | |
|
|
1309 | So in general, you should only use these calls for things that do |
|
|
1310 | (filesystem) I/O, not for things that wait for other events (network, |
|
|
1311 | other processes), although if you are careful and know what you are doing, |
|
|
1312 | you still can. |
|
|
1313 | |
|
|
1314 | The following constants are available and can be used for normal C<ioctl> |
|
|
1315 | and C<fcntl> as well (missing ones are, as usual C<0>): |
|
|
1316 | |
|
|
1317 | C<F_DUPFD_CLOEXEC>, |
|
|
1318 | |
|
|
1319 | C<F_OFD_GETLK>, C<F_OFD_SETLK>, C<F_OFD_GETLKW>, |
|
|
1320 | |
|
|
1321 | C<FIFREEZE>, C<FITHAW>, C<FITRIM>, C<FICLONE>, C<FICLONERANGE>, C<FIDEDUPERANGE>. |
|
|
1322 | |
|
|
1323 | C<F_ADD_SEALS>, C<F_GET_SEALS>, C<F_SEAL_SEAL>, C<F_SEAL_SHRINK>, C<F_SEAL_GROW> and |
|
|
1324 | C<F_SEAL_WRITE>. |
|
|
1325 | |
|
|
1326 | C<FS_IOC_GETFLAGS>, C<FS_IOC_SETFLAGS>, C<FS_IOC_GETVERSION>, C<FS_IOC_SETVERSION>, |
|
|
1327 | C<FS_IOC_FIEMAP>. |
|
|
1328 | |
|
|
1329 | C<FS_IOC_FSGETXATTR>, C<FS_IOC_FSSETXATTR>, C<FS_IOC_SET_ENCRYPTION_POLICY>, |
|
|
1330 | C<FS_IOC_GET_ENCRYPTION_PWSALT>, C<FS_IOC_GET_ENCRYPTION_POLICY>, C<FS_KEY_DESCRIPTOR_SIZE>. |
|
|
1331 | |
|
|
1332 | C<FS_SECRM_FL>, C<FS_UNRM_FL>, C<FS_COMPR_FL>, C<FS_SYNC_FL>, C<FS_IMMUTABLE_FL>, |
|
|
1333 | C<FS_APPEND_FL>, C<FS_NODUMP_FL>, C<FS_NOATIME_FL>, C<FS_DIRTY_FL>, |
|
|
1334 | C<FS_COMPRBLK_FL>, C<FS_NOCOMP_FL>, C<FS_ENCRYPT_FL>, C<FS_BTREE_FL>, |
|
|
1335 | C<FS_INDEX_FL>, C<FS_JOURNAL_DATA_FL>, C<FS_NOTAIL_FL>, C<FS_DIRSYNC_FL>, C<FS_TOPDIR_FL>, |
|
|
1336 | C<FS_FL_USER_MODIFIABLE>. |
|
|
1337 | |
|
|
1338 | C<FS_XFLAG_REALTIME>, C<FS_XFLAG_PREALLOC>, C<FS_XFLAG_IMMUTABLE>, C<FS_XFLAG_APPEND>, |
|
|
1339 | C<FS_XFLAG_SYNC>, C<FS_XFLAG_NOATIME>, C<FS_XFLAG_NODUMP>, C<FS_XFLAG_RTINHERIT>, |
|
|
1340 | C<FS_XFLAG_PROJINHERIT>, C<FS_XFLAG_NOSYMLINKS>, C<FS_XFLAG_EXTSIZE>, C<FS_XFLAG_EXTSZINHERIT>, |
|
|
1341 | C<FS_XFLAG_NODEFRAG>, C<FS_XFLAG_FILESTREAM>, C<FS_XFLAG_DAX>, C<FS_XFLAG_HASATTR>, |
|
|
1342 | |
1043 | =item aio_sync $callback->($status) |
1343 | =item aio_sync $callback->($status) |
1044 | |
1344 | |
1045 | Asynchronously call sync and call the callback when finished. |
1345 | Asynchronously call sync and call the callback when finished. |
1046 | |
1346 | |
1047 | =item aio_fsync $fh, $callback->($status) |
1347 | =item aio_fsync $fh, $callback->($status) |
… | |
… | |
1054 | Asynchronously call fdatasync on the given filehandle and call the |
1354 | Asynchronously call fdatasync on the given filehandle and call the |
1055 | callback with the fdatasync result code. |
1355 | callback with the fdatasync result code. |
1056 | |
1356 | |
1057 | If this call isn't available because your OS lacks it or it couldn't be |
1357 | If this call isn't available because your OS lacks it or it couldn't be |
1058 | detected, it will be emulated by calling C<fsync> instead. |
1358 | detected, it will be emulated by calling C<fsync> instead. |
|
|
1359 | |
|
|
1360 | =item aio_syncfs $fh, $callback->($status) |
|
|
1361 | |
|
|
1362 | Asynchronously call the syncfs syscall to sync the filesystem associated |
|
|
1363 | to the given filehandle and call the callback with the syncfs result |
|
|
1364 | code. If syncfs is not available, calls sync(), but returns C<-1> and sets |
|
|
1365 | errno to C<ENOSYS> nevertheless. |
1059 | |
1366 | |
1060 | =item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
1367 | =item aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
1061 | |
1368 | |
1062 | Sync the data portion of the file specified by C<$offset> and C<$length> |
1369 | Sync the data portion of the file specified by C<$offset> and C<$length> |
1063 | to disk (but NOT the metadata), by calling the Linux-specific |
1370 | to disk (but NOT the metadata), by calling the Linux-specific |
… | |
… | |
1067 | C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>, |
1374 | C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>, |
1068 | C<IO::AIO::SYNC_FILE_RANGE_WRITE> and |
1375 | C<IO::AIO::SYNC_FILE_RANGE_WRITE> and |
1069 | C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range |
1376 | C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range |
1070 | manpage for details. |
1377 | manpage for details. |
1071 | |
1378 | |
1072 | =item aio_pathsync $path, $callback->($status) |
1379 | =item aio_pathsync $pathname, $callback->($status) |
1073 | |
1380 | |
1074 | This request tries to open, fsync and close the given path. This is a |
1381 | This request tries to open, fsync and close the given path. This is a |
1075 | composite request intended to sync directories after directory operations |
1382 | composite request intended to sync directories after directory operations |
1076 | (E.g. rename). This might not work on all operating systems or have any |
1383 | (E.g. rename). This might not work on all operating systems or have any |
1077 | specific effect, but usually it makes sure that directory changes get |
1384 | specific effect, but usually it makes sure that directory changes get |
… | |
… | |
1108 | }; |
1415 | }; |
1109 | |
1416 | |
1110 | $grp |
1417 | $grp |
1111 | } |
1418 | } |
1112 | |
1419 | |
1113 | =item aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
1420 | =item aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status) |
1114 | |
1421 | |
1115 | This is a rather advanced IO::AIO call, which only works on mmap(2)ed |
1422 | This is a rather advanced IO::AIO call, which only works on mmap(2)ed |
1116 | scalars (see the C<IO::AIO::mmap> function, although it also works on data |
1423 | scalars (see the C<IO::AIO::mmap> function, although it also works on data |
1117 | scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the |
1424 | scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the |
1118 | scalar must only be modified in-place while an aio operation is pending on |
1425 | scalar must only be modified in-place while an aio operation is pending on |
… | |
… | |
1120 | |
1427 | |
1121 | It calls the C<msync> function of your OS, if available, with the memory |
1428 | It calls the C<msync> function of your OS, if available, with the memory |
1122 | area starting at C<$offset> in the string and ending C<$length> bytes |
1429 | area starting at C<$offset> in the string and ending C<$length> bytes |
1123 | later. If C<$length> is negative, counts from the end, and if C<$length> |
1430 | later. If C<$length> is negative, counts from the end, and if C<$length> |
1124 | is C<undef>, then it goes till the end of the string. The flags can be |
1431 | is C<undef>, then it goes till the end of the string. The flags can be |
1125 | a combination of C<IO::AIO::MS_ASYNC>, C<IO::AIO::MS_INVALIDATE> and |
1432 | either C<IO::AIO::MS_ASYNC> or C<IO::AIO::MS_SYNC>, plus an optional |
1126 | C<IO::AIO::MS_SYNC>. |
1433 | C<IO::AIO::MS_INVALIDATE>. |
1127 | |
1434 | |
1128 | =item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
1435 | =item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
1129 | |
1436 | |
1130 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
1437 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
1131 | scalars. |
1438 | scalars. |
1132 | |
1439 | |
1133 | It touches (reads or writes) all memory pages in the specified |
1440 | It touches (reads or writes) all memory pages in the specified |
1134 | range inside the scalar. All caveats and parameters are the same |
1441 | range inside the scalar. All caveats and parameters are the same |
1135 | as for C<aio_msync>, above, except for flags, which must be either |
1442 | as for C<aio_msync>, above, except for flags, which must be either |
1136 | C<0> (which reads all pages and ensures they are instantiated) or |
1443 | C<0> (which reads all pages and ensures they are instantiated) or |
1137 | C<IO::AIO::MT_MODIFY>, which modifies the memory page s(by reading and |
1444 | C<IO::AIO::MT_MODIFY>, which modifies the memory pages (by reading and |
1138 | writing an octet from it, which dirties the page). |
1445 | writing an octet from it, which dirties the page). |
1139 | |
1446 | |
1140 | =item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
1447 | =item aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
1141 | |
1448 | |
1142 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
1449 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
… | |
… | |
1161 | IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh; |
1468 | IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh; |
1162 | aio_mlock $data; # mlock in background |
1469 | aio_mlock $data; # mlock in background |
1163 | |
1470 | |
1164 | =item aio_mlockall $flags, $callback->($status) |
1471 | =item aio_mlockall $flags, $callback->($status) |
1165 | |
1472 | |
1166 | Calls the C<mlockall> function with the given C<$flags> (a combination of |
1473 | Calls the C<mlockall> function with the given C<$flags> (a |
1167 | C<IO::AIO::MCL_CURRENT> and C<IO::AIO::MCL_FUTURE>). |
1474 | combination of C<IO::AIO::MCL_CURRENT>, C<IO::AIO::MCL_FUTURE> and |
|
|
1475 | C<IO::AIO::MCL_ONFAULT>). |
1168 | |
1476 | |
1169 | On systems that do not implement C<mlockall>, this function returns C<-1> |
1477 | On systems that do not implement C<mlockall>, this function returns C<-1> |
1170 | and sets errno to C<ENOSYS>. |
1478 | and sets errno to C<ENOSYS>. Similarly, flag combinations not supported |
|
|
1479 | by the system result in a return value of C<-1> with errno being set to |
|
|
1480 | C<EINVAL>. |
1171 | |
1481 | |
1172 | Note that the corresponding C<munlockall> is synchronous and is |
1482 | Note that the corresponding C<munlockall> is synchronous and is |
1173 | documented under L<MISCELLANEOUS FUNCTIONS>. |
1483 | documented under L<MISCELLANEOUS FUNCTIONS>. |
1174 | |
1484 | |
1175 | Example: asynchronously lock all current and future pages into memory. |
1485 | Example: asynchronously lock all current and future pages into memory. |
1176 | |
1486 | |
1177 | aio_mlockall IO::AIO::MCL_FUTURE; |
1487 | aio_mlockall IO::AIO::MCL_FUTURE; |
|
|
1488 | |
|
|
1489 | =item aio_fiemap $fh, $start, $length, $flags, $count, $cb->(\@extents) |
|
|
1490 | |
|
|
1491 | Queries the extents of the given file (by calling the Linux C<FIEMAP> |
|
|
1492 | ioctl, see L<http://cvs.schmorp.de/IO-AIO/doc/fiemap.txt> for details). If |
|
|
1493 | the ioctl is not available on your OS, then this request will fail with |
|
|
1494 | C<ENOSYS>. |
|
|
1495 | |
|
|
1496 | C<$start> is the starting offset to query extents for, C<$length> is the |
|
|
1497 | size of the range to query - if it is C<undef>, then the whole file will |
|
|
1498 | be queried. |
|
|
1499 | |
|
|
1500 | C<$flags> is a combination of flags (C<IO::AIO::FIEMAP_FLAG_SYNC> or |
|
|
1501 | C<IO::AIO::FIEMAP_FLAG_XATTR> - C<IO::AIO::FIEMAP_FLAGS_COMPAT> is also |
|
|
1502 | exported), and is normally C<0> or C<IO::AIO::FIEMAP_FLAG_SYNC> to query |
|
|
1503 | the data portion. |
|
|
1504 | |
|
|
1505 | C<$count> is the maximum number of extent records to return. If it is |
|
|
1506 | C<undef>, then IO::AIO queries all extents of the range. As a very special |
|
|
1507 | case, if it is C<0>, then the callback receives the number of extents |
|
|
1508 | instead of the extents themselves (which is unreliable, see below). |
|
|
1509 | |
|
|
1510 | If an error occurs, the callback receives no arguments. The special |
|
|
1511 | C<errno> value C<IO::AIO::EBADR> is available to test for flag errors. |
|
|
1512 | |
|
|
1513 | Otherwise, the callback receives an array reference with extent |
|
|
1514 | structures. Each extent structure is an array reference itself, with the |
|
|
1515 | following members: |
|
|
1516 | |
|
|
1517 | [$logical, $physical, $length, $flags] |
|
|
1518 | |
|
|
1519 | Flags is any combination of the following flag values (typically either C<0> |
|
|
1520 | or C<IO::AIO::FIEMAP_EXTENT_LAST> (1)): |
|
|
1521 | |
|
|
1522 | C<IO::AIO::FIEMAP_EXTENT_LAST>, C<IO::AIO::FIEMAP_EXTENT_UNKNOWN>, |
|
|
1523 | C<IO::AIO::FIEMAP_EXTENT_DELALLOC>, C<IO::AIO::FIEMAP_EXTENT_ENCODED>, |
|
|
1524 | C<IO::AIO::FIEMAP_EXTENT_DATA_ENCRYPTED>, C<IO::AIO::FIEMAP_EXTENT_NOT_ALIGNED>, |
|
|
1525 | C<IO::AIO::FIEMAP_EXTENT_DATA_INLINE>, C<IO::AIO::FIEMAP_EXTENT_DATA_TAIL>, |
|
|
1526 | C<IO::AIO::FIEMAP_EXTENT_UNWRITTEN>, C<IO::AIO::FIEMAP_EXTENT_MERGED> or |
|
|
1527 | C<IO::AIO::FIEMAP_EXTENT_SHARED>. |
|
|
1528 | |
|
|
1529 | At the time of this writing (Linux 3.2), this request is unreliable unless |
|
|
1530 | C<$count> is C<undef>, as the kernel has all sorts of bugs preventing |
|
|
1531 | it to return all extents of a range for files with a large number of |
|
|
1532 | extents. The code (only) works around all these issues if C<$count> is |
|
|
1533 | C<undef>. |
1178 | |
1534 | |
1179 | =item aio_group $callback->(...) |
1535 | =item aio_group $callback->(...) |
1180 | |
1536 | |
1181 | This is a very special aio request: Instead of doing something, it is a |
1537 | This is a very special aio request: Instead of doing something, it is a |
1182 | container for other aio requests, which is useful if you want to bundle |
1538 | container for other aio requests, which is useful if you want to bundle |
… | |
… | |
1219 | like sleep and file handle readable/writable, the overhead this creates is |
1575 | like sleep and file handle readable/writable, the overhead this creates is |
1220 | immense (it blocks a thread for a long time) so do not use this function |
1576 | immense (it blocks a thread for a long time) so do not use this function |
1221 | except to put your application under artificial I/O pressure. |
1577 | except to put your application under artificial I/O pressure. |
1222 | |
1578 | |
1223 | =back |
1579 | =back |
|
|
1580 | |
|
|
1581 | |
|
|
1582 | =head2 IO::AIO::WD - multiple working directories |
|
|
1583 | |
|
|
1584 | Your process only has one current working directory, which is used by all |
|
|
1585 | threads. This makes it hard to use relative paths (some other component |
|
|
1586 | could call C<chdir> at any time, and it is hard to control when the path |
|
|
1587 | will be used by IO::AIO). |
|
|
1588 | |
|
|
1589 | One solution for this is to always use absolute paths. This usually works, |
|
|
1590 | but can be quite slow (the kernel has to walk the whole path on every |
|
|
1591 | access), and can also be a hassle to implement. |
|
|
1592 | |
|
|
1593 | Newer POSIX systems have a number of functions (openat, fdopendir, |
|
|
1594 | futimensat and so on) that make it possible to specify working directories |
|
|
1595 | per operation. |
|
|
1596 | |
|
|
1597 | For portability, and because the clowns who "designed", or shall I write, |
|
|
1598 | perpetrated this new interface were obviously half-drunk, this abstraction |
|
|
1599 | cannot be perfect, though. |
|
|
1600 | |
|
|
1601 | IO::AIO allows you to convert directory paths into a so-called IO::AIO::WD |
|
|
1602 | object. This object stores the canonicalised, absolute version of the |
|
|
1603 | path, and on systems that allow it, also a directory file descriptor. |
|
|
1604 | |
|
|
1605 | Everywhere where a pathname is accepted by IO::AIO (e.g. in C<aio_stat> |
|
|
1606 | or C<aio_unlink>), one can specify an array reference with an IO::AIO::WD |
|
|
1607 | object and a pathname instead (or the IO::AIO::WD object alone, which |
|
|
1608 | gets interpreted as C<[$wd, "."]>). If the pathname is absolute, the |
|
|
1609 | IO::AIO::WD object is ignored, otherwise the pathname is resolved relative |
|
|
1610 | to that IO::AIO::WD object. |
|
|
1611 | |
|
|
1612 | For example, to get a wd object for F</etc> and then stat F<passwd> |
|
|
1613 | inside, you would write: |
|
|
1614 | |
|
|
1615 | aio_wd "/etc", sub { |
|
|
1616 | my $etcdir = shift; |
|
|
1617 | |
|
|
1618 | # although $etcdir can be undef on error, there is generally no reason |
|
|
1619 | # to check for errors here, as aio_stat will fail with ENOENT |
|
|
1620 | # when $etcdir is undef. |
|
|
1621 | |
|
|
1622 | aio_stat [$etcdir, "passwd"], sub { |
|
|
1623 | # yay |
|
|
1624 | }; |
|
|
1625 | }; |
|
|
1626 | |
|
|
1627 | The fact that C<aio_wd> is a request and not a normal function shows that |
|
|
1628 | creating an IO::AIO::WD object is itself a potentially blocking operation, |
|
|
1629 | which is why it is done asynchronously. |
|
|
1630 | |
|
|
1631 | To stat the directory obtained with C<aio_wd> above, one could write |
|
|
1632 | either of the following three request calls: |
|
|
1633 | |
|
|
1634 | aio_lstat "/etc" , sub { ... # pathname as normal string |
|
|
1635 | aio_lstat [$wd, "."], sub { ... # "." relative to $wd (i.e. $wd itself) |
|
|
1636 | aio_lstat $wd , sub { ... # shorthand for the previous |
|
|
1637 | |
|
|
1638 | As with normal pathnames, IO::AIO keeps a copy of the working directory |
|
|
1639 | object and the pathname string, so you could write the following without |
|
|
1640 | causing any issues due to C<$path> getting reused: |
|
|
1641 | |
|
|
1642 | my $path = [$wd, undef]; |
|
|
1643 | |
|
|
1644 | for my $name (qw(abc def ghi)) { |
|
|
1645 | $path->[1] = $name; |
|
|
1646 | aio_stat $path, sub { |
|
|
1647 | # ... |
|
|
1648 | }; |
|
|
1649 | } |
|
|
1650 | |
|
|
1651 | There are some caveats: when directories get renamed (or deleted), the |
|
|
1652 | pathname string doesn't change, so will point to the new directory (or |
|
|
1653 | nowhere at all), while the directory fd, if available on the system, |
|
|
1654 | will still point to the original directory. Most functions accepting a |
|
|
1655 | pathname will use the directory fd on newer systems, and the string on |
|
|
1656 | older systems. Some functions (such as C<aio_realpath>) will always rely on |
|
|
1657 | the string form of the pathname. |
|
|
1658 | |
|
|
1659 | So this functionality is mainly useful to get some protection against |
|
|
1660 | C<chdir>, to easily get an absolute path out of a relative path for future |
|
|
1661 | reference, and to speed up doing many operations in the same directory |
|
|
1662 | (e.g. when stat'ing all files in a directory). |
|
|
1663 | |
|
|
1664 | The following functions implement this working directory abstraction: |
|
|
1665 | |
|
|
1666 | =over 4 |
|
|
1667 | |
|
|
1668 | =item aio_wd $pathname, $callback->($wd) |
|
|
1669 | |
|
|
1670 | Asynchonously canonicalise the given pathname and convert it to an |
|
|
1671 | IO::AIO::WD object representing it. If possible and supported on the |
|
|
1672 | system, also open a directory fd to speed up pathname resolution relative |
|
|
1673 | to this working directory. |
|
|
1674 | |
|
|
1675 | If something goes wrong, then C<undef> is passwd to the callback instead |
|
|
1676 | of a working directory object and C<$!> is set appropriately. Since |
|
|
1677 | passing C<undef> as working directory component of a pathname fails the |
|
|
1678 | request with C<ENOENT>, there is often no need for error checking in the |
|
|
1679 | C<aio_wd> callback, as future requests using the value will fail in the |
|
|
1680 | expected way. |
|
|
1681 | |
|
|
1682 | =item IO::AIO::CWD |
|
|
1683 | |
|
|
1684 | This is a compile time constant (object) that represents the process |
|
|
1685 | current working directory. |
|
|
1686 | |
|
|
1687 | Specifying this object as working directory object for a pathname is as if |
|
|
1688 | the pathname would be specified directly, without a directory object. For |
|
|
1689 | example, these calls are functionally identical: |
|
|
1690 | |
|
|
1691 | aio_stat "somefile", sub { ... }; |
|
|
1692 | aio_stat [IO::AIO::CWD, "somefile"], sub { ... }; |
|
|
1693 | |
|
|
1694 | =back |
|
|
1695 | |
|
|
1696 | To recover the path associated with an IO::AIO::WD object, you can use |
|
|
1697 | C<aio_realpath>: |
|
|
1698 | |
|
|
1699 | aio_realpath $wd, sub { |
|
|
1700 | warn "path is $_[0]\n"; |
|
|
1701 | }; |
|
|
1702 | |
|
|
1703 | Currently, C<aio_statvfs> always, and C<aio_rename> and C<aio_rmdir> |
|
|
1704 | sometimes, fall back to using an absolue path. |
1224 | |
1705 | |
1225 | =head2 IO::AIO::REQ CLASS |
1706 | =head2 IO::AIO::REQ CLASS |
1226 | |
1707 | |
1227 | All non-aggregate C<aio_*> functions return an object of this class when |
1708 | All non-aggregate C<aio_*> functions return an object of this class when |
1228 | called in non-void context. |
1709 | called in non-void context. |
… | |
… | |
1346 | |
1827 | |
1347 | Sets a feeder/generator on this group: every group can have an attached |
1828 | Sets a feeder/generator on this group: every group can have an attached |
1348 | generator that generates requests if idle. The idea behind this is that, |
1829 | generator that generates requests if idle. The idea behind this is that, |
1349 | although you could just queue as many requests as you want in a group, |
1830 | although you could just queue as many requests as you want in a group, |
1350 | this might starve other requests for a potentially long time. For example, |
1831 | this might starve other requests for a potentially long time. For example, |
1351 | C<aio_scandir> might generate hundreds of thousands C<aio_stat> requests, |
1832 | C<aio_scandir> might generate hundreds of thousands of C<aio_stat> |
1352 | delaying any later requests for a long time. |
1833 | requests, delaying any later requests for a long time. |
1353 | |
1834 | |
1354 | To avoid this, and allow incremental generation of requests, you can |
1835 | To avoid this, and allow incremental generation of requests, you can |
1355 | instead a group and set a feeder on it that generates those requests. The |
1836 | instead a group and set a feeder on it that generates those requests. The |
1356 | feed callback will be called whenever there are few enough (see C<limit>, |
1837 | feed callback will be called whenever there are few enough (see C<limit>, |
1357 | below) requests active in the group itself and is expected to queue more |
1838 | below) requests active in the group itself and is expected to queue more |
… | |
… | |
1389 | The default value for the limit is C<0>, but note that setting a feeder |
1870 | The default value for the limit is C<0>, but note that setting a feeder |
1390 | automatically bumps it up to C<2>. |
1871 | automatically bumps it up to C<2>. |
1391 | |
1872 | |
1392 | =back |
1873 | =back |
1393 | |
1874 | |
|
|
1875 | |
1394 | =head2 SUPPORT FUNCTIONS |
1876 | =head2 SUPPORT FUNCTIONS |
1395 | |
1877 | |
1396 | =head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION |
1878 | =head3 EVENT PROCESSING AND EVENT LOOP INTEGRATION |
1397 | |
1879 | |
1398 | =over 4 |
1880 | =over 4 |
… | |
… | |
1406 | |
1888 | |
1407 | See C<poll_cb> for an example. |
1889 | See C<poll_cb> for an example. |
1408 | |
1890 | |
1409 | =item IO::AIO::poll_cb |
1891 | =item IO::AIO::poll_cb |
1410 | |
1892 | |
1411 | Process some outstanding events on the result pipe. You have to call this |
1893 | Process some requests that have reached the result phase (i.e. they have |
1412 | regularly. Returns C<0> if all events could be processed, or C<-1> if it |
1894 | been executed but the results are not yet reported). You have to call |
1413 | returned earlier for whatever reason. Returns immediately when no events |
1895 | this "regularly" to finish outstanding requests. |
1414 | are outstanding. The amount of events processed depends on the settings of |
|
|
1415 | C<IO::AIO::max_poll_req> and C<IO::AIO::max_poll_time>. |
|
|
1416 | |
1896 | |
|
|
1897 | Returns C<0> if all events could be processed (or there were no |
|
|
1898 | events to process), or C<-1> if it returned earlier for whatever |
|
|
1899 | reason. Returns immediately when no events are outstanding. The amount |
|
|
1900 | of events processed depends on the settings of C<IO::AIO::max_poll_req>, |
|
|
1901 | C<IO::AIO::max_poll_time> and C<IO::AIO::max_outstanding>. |
|
|
1902 | |
1417 | If not all requests were processed for whatever reason, the filehandle |
1903 | If not all requests were processed for whatever reason, the poll file |
1418 | will still be ready when C<poll_cb> returns, so normally you don't have to |
1904 | descriptor will still be ready when C<poll_cb> returns, so normally you |
1419 | do anything special to have it called later. |
1905 | don't have to do anything special to have it called later. |
|
|
1906 | |
|
|
1907 | Apart from calling C<IO::AIO::poll_cb> when the event filehandle becomes |
|
|
1908 | ready, it can be beneficial to call this function from loops which submit |
|
|
1909 | a lot of requests, to make sure the results get processed when they become |
|
|
1910 | available and not just when the loop is finished and the event loop takes |
|
|
1911 | over again. This function returns very fast when there are no outstanding |
|
|
1912 | requests. |
1420 | |
1913 | |
1421 | Example: Install an Event watcher that automatically calls |
1914 | Example: Install an Event watcher that automatically calls |
1422 | IO::AIO::poll_cb with high priority (more examples can be found in the |
1915 | IO::AIO::poll_cb with high priority (more examples can be found in the |
1423 | SYNOPSIS section, at the top of this document): |
1916 | SYNOPSIS section, at the top of this document): |
1424 | |
1917 | |
… | |
… | |
1426 | poll => 'r', async => 1, |
1919 | poll => 'r', async => 1, |
1427 | cb => \&IO::AIO::poll_cb); |
1920 | cb => \&IO::AIO::poll_cb); |
1428 | |
1921 | |
1429 | =item IO::AIO::poll_wait |
1922 | =item IO::AIO::poll_wait |
1430 | |
1923 | |
1431 | If there are any outstanding requests and none of them in the result |
1924 | Wait until either at least one request is in the result phase or no |
1432 | phase, wait till the result filehandle becomes ready for reading (simply |
1925 | requests are outstanding anymore. |
1433 | does a C<select> on the filehandle. This is useful if you want to |
1926 | |
1434 | synchronously wait for some requests to finish). |
1927 | This is useful if you want to synchronously wait for some requests to |
|
|
1928 | become ready, without actually handling them. |
1435 | |
1929 | |
1436 | See C<nreqs> for an example. |
1930 | See C<nreqs> for an example. |
1437 | |
1931 | |
1438 | =item IO::AIO::poll |
1932 | =item IO::AIO::poll |
1439 | |
1933 | |
… | |
… | |
1450 | |
1944 | |
1451 | Strictly equivalent to: |
1945 | Strictly equivalent to: |
1452 | |
1946 | |
1453 | IO::AIO::poll_wait, IO::AIO::poll_cb |
1947 | IO::AIO::poll_wait, IO::AIO::poll_cb |
1454 | while IO::AIO::nreqs; |
1948 | while IO::AIO::nreqs; |
|
|
1949 | |
|
|
1950 | This function can be useful at program aborts, to make sure outstanding |
|
|
1951 | I/O has been done (C<IO::AIO> uses an C<END> block which already calls |
|
|
1952 | this function on normal exits), or when you are merely using C<IO::AIO> |
|
|
1953 | for its more advanced functions, rather than for async I/O, e.g.: |
|
|
1954 | |
|
|
1955 | my ($dirs, $nondirs); |
|
|
1956 | IO::AIO::aio_scandir "/tmp", 0, sub { ($dirs, $nondirs) = @_ }; |
|
|
1957 | IO::AIO::flush; |
|
|
1958 | # $dirs, $nondirs are now set |
1455 | |
1959 | |
1456 | =item IO::AIO::max_poll_reqs $nreqs |
1960 | =item IO::AIO::max_poll_reqs $nreqs |
1457 | |
1961 | |
1458 | =item IO::AIO::max_poll_time $seconds |
1962 | =item IO::AIO::max_poll_time $seconds |
1459 | |
1963 | |
… | |
… | |
1486 | poll => 'r', nice => 1, |
1990 | poll => 'r', nice => 1, |
1487 | cb => &IO::AIO::poll_cb); |
1991 | cb => &IO::AIO::poll_cb); |
1488 | |
1992 | |
1489 | =back |
1993 | =back |
1490 | |
1994 | |
|
|
1995 | |
1491 | =head3 CONTROLLING THE NUMBER OF THREADS |
1996 | =head3 CONTROLLING THE NUMBER OF THREADS |
1492 | |
1997 | |
1493 | =over |
1998 | =over |
1494 | |
1999 | |
1495 | =item IO::AIO::min_parallel $nthreads |
2000 | =item IO::AIO::min_parallel $nthreads |
… | |
… | |
1547 | Sets the minimum idle timeout (default 10) after which worker threads are |
2052 | Sets the minimum idle timeout (default 10) after which worker threads are |
1548 | allowed to exit. SEe C<IO::AIO::max_idle>. |
2053 | allowed to exit. SEe C<IO::AIO::max_idle>. |
1549 | |
2054 | |
1550 | =item IO::AIO::max_outstanding $maxreqs |
2055 | =item IO::AIO::max_outstanding $maxreqs |
1551 | |
2056 | |
|
|
2057 | Sets the maximum number of outstanding requests to C<$nreqs>. If |
|
|
2058 | you do queue up more than this number of requests, the next call to |
|
|
2059 | C<IO::AIO::poll_cb> (and other functions calling C<poll_cb>, such as |
|
|
2060 | C<IO::AIO::flush> or C<IO::AIO::poll>) will block until the limit is no |
|
|
2061 | longer exceeded. |
|
|
2062 | |
|
|
2063 | In other words, this setting does not enforce a queue limit, but can be |
|
|
2064 | used to make poll functions block if the limit is exceeded. |
|
|
2065 | |
1552 | This is a very bad function to use in interactive programs because it |
2066 | This is a very bad function to use in interactive programs because it |
1553 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
2067 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
1554 | use an C<aio_group> together with a feed callback. |
2068 | use an C<aio_group> together with a feed callback. |
1555 | |
2069 | |
1556 | Sets the maximum number of outstanding requests to C<$nreqs>. If you |
2070 | Its main use is in scripts without an event loop - when you want to stat |
1557 | do queue up more than this number of requests, the next call to the |
2071 | a lot of files, you can write something like this: |
1558 | C<poll_cb> (and C<poll_some> and other functions calling C<poll_cb>) |
|
|
1559 | function will block until the limit is no longer exceeded. |
|
|
1560 | |
2072 | |
1561 | The default value is very large, so there is no practical limit on the |
2073 | IO::AIO::max_outstanding 32; |
1562 | number of outstanding requests. |
|
|
1563 | |
2074 | |
1564 | You can still queue as many requests as you want. Therefore, |
2075 | for my $path (...) { |
1565 | C<max_outstanding> is mainly useful in simple scripts (with low values) or |
2076 | aio_stat $path , ...; |
1566 | as a stop gap to shield against fatal memory overflow (with large values). |
2077 | IO::AIO::poll_cb; |
|
|
2078 | } |
|
|
2079 | |
|
|
2080 | IO::AIO::flush; |
|
|
2081 | |
|
|
2082 | The call to C<poll_cb> inside the loop will normally return instantly, but |
|
|
2083 | as soon as more thna C<32> reqeusts are in-flight, it will block until |
|
|
2084 | some requests have been handled. This keeps the loop from pushing a large |
|
|
2085 | number of C<aio_stat> requests onto the queue. |
|
|
2086 | |
|
|
2087 | The default value for C<max_outstanding> is very large, so there is no |
|
|
2088 | practical limit on the number of outstanding requests. |
1567 | |
2089 | |
1568 | =back |
2090 | =back |
|
|
2091 | |
1569 | |
2092 | |
1570 | =head3 STATISTICAL INFORMATION |
2093 | =head3 STATISTICAL INFORMATION |
1571 | |
2094 | |
1572 | =over |
2095 | =over |
1573 | |
2096 | |
… | |
… | |
1591 | Returns the number of requests currently in the pending state (executed, |
2114 | Returns the number of requests currently in the pending state (executed, |
1592 | but not yet processed by poll_cb). |
2115 | but not yet processed by poll_cb). |
1593 | |
2116 | |
1594 | =back |
2117 | =back |
1595 | |
2118 | |
|
|
2119 | |
|
|
2120 | =head3 SUBSECOND STAT TIME ACCESS |
|
|
2121 | |
|
|
2122 | Both C<aio_stat>/C<aio_lstat> and perl's C<stat>/C<lstat> functions can |
|
|
2123 | generally find access/modification and change times with subsecond time |
|
|
2124 | accuracy of the system supports it, but perl's built-in functions only |
|
|
2125 | return the integer part. |
|
|
2126 | |
|
|
2127 | The following functions return the timestamps of the most recent |
|
|
2128 | stat with subsecond precision on most systems and work both after |
|
|
2129 | C<aio_stat>/C<aio_lstat> and perl's C<stat>/C<lstat> calls. Their return |
|
|
2130 | value is only meaningful after a successful C<stat>/C<lstat> call, or |
|
|
2131 | during/after a successful C<aio_stat>/C<aio_lstat> callback. |
|
|
2132 | |
|
|
2133 | This is similar to the L<Time::HiRes> C<stat> functions, but can return |
|
|
2134 | full resolution without rounding and work with standard perl C<stat>, |
|
|
2135 | alleviating the need to call the special C<Time::HiRes> functions, which |
|
|
2136 | do not act like their perl counterparts. |
|
|
2137 | |
|
|
2138 | On operating systems or file systems where subsecond time resolution is |
|
|
2139 | not supported or could not be detected, a fractional part of C<0> is |
|
|
2140 | returned, so it is always safe to call these functions. |
|
|
2141 | |
|
|
2142 | =over 4 |
|
|
2143 | |
|
|
2144 | =item $seconds = IO::AIO::st_atime, IO::AIO::st_mtime, IO::AIO::st_ctime, IO::AIO::st_btime |
|
|
2145 | |
|
|
2146 | Return the access, modication, change or birth time, respectively, |
|
|
2147 | including fractional part. Due to the limited precision of floating point, |
|
|
2148 | the accuracy on most platforms is only a bit better than milliseconds |
|
|
2149 | for times around now - see the I<nsec> function family, below, for full |
|
|
2150 | accuracy. |
|
|
2151 | |
|
|
2152 | File birth time is only available when the OS and perl support it (on |
|
|
2153 | FreeBSD and NetBSD at the time of this writing, although support is |
|
|
2154 | adaptive, so if your OS/perl gains support, IO::AIO can take advantage of |
|
|
2155 | it). On systems where it isn't available, C<0> is currently returned, but |
|
|
2156 | this might change to C<undef> in a future version. |
|
|
2157 | |
|
|
2158 | =item ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtime |
|
|
2159 | |
|
|
2160 | Returns access, modification, change and birth time all in one go, and |
|
|
2161 | maybe more times in the future version. |
|
|
2162 | |
|
|
2163 | =item $nanoseconds = IO::AIO::st_atimensec, IO::AIO::st_mtimensec, IO::AIO::st_ctimensec, IO::AIO::st_btimensec |
|
|
2164 | |
|
|
2165 | Return the fractional access, modifcation, change or birth time, in nanoseconds, |
|
|
2166 | as an integer in the range C<0> to C<999999999>. |
|
|
2167 | |
|
|
2168 | Note that no accessors are provided for access, modification and |
|
|
2169 | change times - you need to get those from C<stat _> if required (C<int |
|
|
2170 | IO::AIO::st_atime> and so on will I<not> generally give you the correct |
|
|
2171 | value). |
|
|
2172 | |
|
|
2173 | =item $seconds = IO::AIO::st_btimesec |
|
|
2174 | |
|
|
2175 | The (integral) seconds part of the file birth time, if available. |
|
|
2176 | |
|
|
2177 | =item ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtimensec |
|
|
2178 | |
|
|
2179 | Like the functions above, but returns all four times in one go (and maybe |
|
|
2180 | more in future versions). |
|
|
2181 | |
|
|
2182 | =item $counter = IO::AIO::st_gen |
|
|
2183 | |
|
|
2184 | Returns the generation counter (in practice this is just a random number) |
|
|
2185 | of the file. This is only available on platforms which have this member in |
|
|
2186 | their C<struct stat> (most BSDs at the time of this writing) and generally |
|
|
2187 | only to the root usert. If unsupported, C<0> is returned, but this might |
|
|
2188 | change to C<undef> in a future version. |
|
|
2189 | |
|
|
2190 | =back |
|
|
2191 | |
|
|
2192 | Example: print the high resolution modification time of F</etc>, using |
|
|
2193 | C<stat>, and C<IO::AIO::aio_stat>. |
|
|
2194 | |
|
|
2195 | if (stat "/etc") { |
|
|
2196 | printf "stat(/etc) mtime: %f\n", IO::AIO::st_mtime; |
|
|
2197 | } |
|
|
2198 | |
|
|
2199 | IO::AIO::aio_stat "/etc", sub { |
|
|
2200 | $_[0] |
|
|
2201 | and return; |
|
|
2202 | |
|
|
2203 | printf "aio_stat(/etc) mtime: %d.%09d\n", (stat _)[9], IO::AIO::st_mtimensec; |
|
|
2204 | }; |
|
|
2205 | |
|
|
2206 | IO::AIO::flush; |
|
|
2207 | |
|
|
2208 | Output of the awbove on my system, showing reduced and full accuracy: |
|
|
2209 | |
|
|
2210 | stat(/etc) mtime: 1534043702.020808 |
|
|
2211 | aio_stat(/etc) mtime: 1534043702.020807792 |
|
|
2212 | |
|
|
2213 | |
1596 | =head3 MISCELLANEOUS FUNCTIONS |
2214 | =head3 MISCELLANEOUS FUNCTIONS |
1597 | |
2215 | |
1598 | IO::AIO implements some functions that might be useful, but are not |
2216 | IO::AIO implements some functions that are useful when you want to use |
1599 | asynchronous. |
2217 | some "Advanced I/O" function not available to in Perl, without going the |
|
|
2218 | "Asynchronous I/O" route. Many of these have an asynchronous C<aio_*> |
|
|
2219 | counterpart. |
1600 | |
2220 | |
1601 | =over 4 |
2221 | =over 4 |
|
|
2222 | |
|
|
2223 | =item $numfd = IO::AIO::get_fdlimit |
|
|
2224 | |
|
|
2225 | Tries to find the current file descriptor limit and returns it, or |
|
|
2226 | C<undef> and sets C<$!> in case of an error. The limit is one larger than |
|
|
2227 | the highest valid file descriptor number. |
|
|
2228 | |
|
|
2229 | =item IO::AIO::min_fdlimit [$numfd] |
|
|
2230 | |
|
|
2231 | Try to increase the current file descriptor limit(s) to at least C<$numfd> |
|
|
2232 | by changing the soft or hard file descriptor resource limit. If C<$numfd> |
|
|
2233 | is missing, it will try to set a very high limit, although this is not |
|
|
2234 | recommended when you know the actual minimum that you require. |
|
|
2235 | |
|
|
2236 | If the limit cannot be raised enough, the function makes a best-effort |
|
|
2237 | attempt to increase the limit as much as possible, using various |
|
|
2238 | tricks, while still failing. You can query the resulting limit using |
|
|
2239 | C<IO::AIO::get_fdlimit>. |
|
|
2240 | |
|
|
2241 | If an error occurs, returns C<undef> and sets C<$!>, otherwise returns |
|
|
2242 | true. |
1602 | |
2243 | |
1603 | =item IO::AIO::sendfile $ofh, $ifh, $offset, $count |
2244 | =item IO::AIO::sendfile $ofh, $ifh, $offset, $count |
1604 | |
2245 | |
1605 | Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>, |
2246 | Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>, |
1606 | but is blocking (this makes most sense if you know the input data is |
2247 | but is blocking (this makes most sense if you know the input data is |
… | |
… | |
1611 | |
2252 | |
1612 | =item IO::AIO::fadvise $fh, $offset, $len, $advice |
2253 | =item IO::AIO::fadvise $fh, $offset, $len, $advice |
1613 | |
2254 | |
1614 | Simply calls the C<posix_fadvise> function (see its |
2255 | Simply calls the C<posix_fadvise> function (see its |
1615 | manpage for details). The following advice constants are |
2256 | manpage for details). The following advice constants are |
1616 | avaiable: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>, |
2257 | available: C<IO::AIO::FADV_NORMAL>, C<IO::AIO::FADV_SEQUENTIAL>, |
1617 | C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>, |
2258 | C<IO::AIO::FADV_RANDOM>, C<IO::AIO::FADV_NOREUSE>, |
1618 | C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>. |
2259 | C<IO::AIO::FADV_WILLNEED>, C<IO::AIO::FADV_DONTNEED>. |
1619 | |
2260 | |
1620 | On systems that do not implement C<posix_fadvise>, this function returns |
2261 | On systems that do not implement C<posix_fadvise>, this function returns |
1621 | ENOSYS, otherwise the return value of C<posix_fadvise>. |
2262 | ENOSYS, otherwise the return value of C<posix_fadvise>. |
1622 | |
2263 | |
1623 | =item IO::AIO::madvise $scalar, $offset, $len, $advice |
2264 | =item IO::AIO::madvise $scalar, $offset, $len, $advice |
1624 | |
2265 | |
1625 | Simply calls the C<posix_madvise> function (see its |
2266 | Simply calls the C<posix_madvise> function (see its |
1626 | manpage for details). The following advice constants are |
2267 | manpage for details). The following advice constants are |
1627 | avaiable: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>, |
2268 | available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>, |
1628 | C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>. |
2269 | C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, |
|
|
2270 | C<IO::AIO::MADV_DONTNEED>. |
|
|
2271 | |
|
|
2272 | If C<$offset> is negative, counts from the end. If C<$length> is negative, |
|
|
2273 | the remaining length of the C<$scalar> is used. If possible, C<$length> |
|
|
2274 | will be reduced to fit into the C<$scalar>. |
1629 | |
2275 | |
1630 | On systems that do not implement C<posix_madvise>, this function returns |
2276 | On systems that do not implement C<posix_madvise>, this function returns |
1631 | ENOSYS, otherwise the return value of C<posix_madvise>. |
2277 | ENOSYS, otherwise the return value of C<posix_madvise>. |
1632 | |
2278 | |
1633 | =item IO::AIO::mprotect $scalar, $offset, $len, $protect |
2279 | =item IO::AIO::mprotect $scalar, $offset, $len, $protect |
1634 | |
2280 | |
1635 | Simply calls the C<mprotect> function on the preferably AIO::mmap'ed |
2281 | Simply calls the C<mprotect> function on the preferably AIO::mmap'ed |
1636 | $scalar (see its manpage for details). The following protect |
2282 | $scalar (see its manpage for details). The following protect |
1637 | constants are avaiable: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>, |
2283 | constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>, |
1638 | C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>. |
2284 | C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>. |
|
|
2285 | |
|
|
2286 | If C<$offset> is negative, counts from the end. If C<$length> is negative, |
|
|
2287 | the remaining length of the C<$scalar> is used. If possible, C<$length> |
|
|
2288 | will be reduced to fit into the C<$scalar>. |
1639 | |
2289 | |
1640 | On systems that do not implement C<mprotect>, this function returns |
2290 | On systems that do not implement C<mprotect>, this function returns |
1641 | ENOSYS, otherwise the return value of C<mprotect>. |
2291 | ENOSYS, otherwise the return value of C<mprotect>. |
1642 | |
2292 | |
1643 | =item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
2293 | =item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
1644 | |
2294 | |
1645 | Memory-maps a file (or anonymous memory range) and attaches it to the |
2295 | Memory-maps a file (or anonymous memory range) and attaches it to the |
1646 | given C<$scalar>, which will act like a string scalar. |
2296 | given C<$scalar>, which will act like a string scalar. Returns true on |
|
|
2297 | success, and false otherwise. |
1647 | |
2298 | |
|
|
2299 | The scalar must exist, but its contents do not matter - this means you |
|
|
2300 | cannot use a nonexistant array or hash element. When in doubt, C<undef> |
|
|
2301 | the scalar first. |
|
|
2302 | |
1648 | The only operations allowed on the scalar are C<substr>/C<vec> that don't |
2303 | The only operations allowed on the mmapped scalar are C<substr>/C<vec>, |
1649 | change the string length, and most read-only operations such as copying it |
2304 | which don't change the string length, and most read-only operations such |
1650 | or searching it with regexes and so on. |
2305 | as copying it or searching it with regexes and so on. |
1651 | |
2306 | |
1652 | Anything else is unsafe and will, at best, result in memory leaks. |
2307 | Anything else is unsafe and will, at best, result in memory leaks. |
1653 | |
2308 | |
1654 | The memory map associated with the C<$scalar> is automatically removed |
2309 | The memory map associated with the C<$scalar> is automatically removed |
1655 | when the C<$scalar> is destroyed, or when the C<IO::AIO::mmap> or |
2310 | when the C<$scalar> is undef'd or destroyed, or when the C<IO::AIO::mmap> |
1656 | C<IO::AIO::munmap> functions are called. |
2311 | or C<IO::AIO::munmap> functions are called on it. |
1657 | |
2312 | |
1658 | This calls the C<mmap>(2) function internally. See your system's manual |
2313 | This calls the C<mmap>(2) function internally. See your system's manual |
1659 | page for details on the C<$length>, C<$prot> and C<$flags> parameters. |
2314 | page for details on the C<$length>, C<$prot> and C<$flags> parameters. |
1660 | |
2315 | |
1661 | The C<$length> must be larger than zero and smaller than the actual |
2316 | The C<$length> must be larger than zero and smaller than the actual |
1662 | filesize. |
2317 | filesize. |
1663 | |
2318 | |
1664 | C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>, |
2319 | C<$prot> is a combination of C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_EXEC>, |
1665 | C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>, |
2320 | C<IO::AIO::PROT_READ> and/or C<IO::AIO::PROT_WRITE>, |
1666 | |
2321 | |
1667 | C<$flags> can be a combination of C<IO::AIO::MAP_SHARED> or |
2322 | C<$flags> can be a combination of |
1668 | C<IO::AIO::MAP_PRIVATE>, or a number of system-specific flags (when |
2323 | C<IO::AIO::MAP_SHARED> or |
1669 | not available, the are defined as 0): C<IO::AIO::MAP_ANONYMOUS> |
2324 | C<IO::AIO::MAP_PRIVATE>, |
|
|
2325 | or a number of system-specific flags (when not available, the are C<0>): |
1670 | (which is set to C<MAP_ANON> if your system only provides this |
2326 | C<IO::AIO::MAP_ANONYMOUS> (which is set to C<MAP_ANON> if your system only provides this constant), |
1671 | constant), C<IO::AIO::MAP_HUGETLB>, C<IO::AIO::MAP_LOCKED>, |
2327 | C<IO::AIO::MAP_LOCKED>, |
1672 | C<IO::AIO::MAP_NORESERVE>, C<IO::AIO::MAP_POPULATE> or |
2328 | C<IO::AIO::MAP_NORESERVE>, |
|
|
2329 | C<IO::AIO::MAP_POPULATE>, |
1673 | C<IO::AIO::MAP_NONBLOCK> |
2330 | C<IO::AIO::MAP_NONBLOCK>, |
|
|
2331 | C<IO::AIO::MAP_FIXED>, |
|
|
2332 | C<IO::AIO::MAP_GROWSDOWN>, |
|
|
2333 | C<IO::AIO::MAP_32BIT>, |
|
|
2334 | C<IO::AIO::MAP_HUGETLB> or |
|
|
2335 | C<IO::AIO::MAP_STACK>. |
1674 | |
2336 | |
1675 | If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed. |
2337 | If C<$fh> is C<undef>, then a file descriptor of C<-1> is passed. |
1676 | |
2338 | |
1677 | C<$offset> is the offset from the start of the file - it generally must be |
2339 | C<$offset> is the offset from the start of the file - it generally must be |
1678 | a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>. |
2340 | a multiple of C<IO::AIO::PAGESIZE> and defaults to C<0>. |
… | |
… | |
1692 | |
2354 | |
1693 | =item IO::AIO::munmap $scalar |
2355 | =item IO::AIO::munmap $scalar |
1694 | |
2356 | |
1695 | Removes a previous mmap and undefines the C<$scalar>. |
2357 | Removes a previous mmap and undefines the C<$scalar>. |
1696 | |
2358 | |
|
|
2359 | =item IO::AIO::mremap $scalar, $new_length, $flags = MREMAP_MAYMOVE[, $new_address = 0] |
|
|
2360 | |
|
|
2361 | Calls the Linux-specific mremap(2) system call. The C<$scalar> must have |
|
|
2362 | been mapped by C<IO::AIO::mmap>, and C<$flags> must currently either be |
|
|
2363 | C<0> or C<IO::AIO::MREMAP_MAYMOVE>. |
|
|
2364 | |
|
|
2365 | Returns true if successful, and false otherwise. If the underlying mmapped |
|
|
2366 | region has changed address, then the true value has the numerical value |
|
|
2367 | C<1>, otherwise it has the numerical value C<0>: |
|
|
2368 | |
|
|
2369 | my $success = IO::AIO::mremap $mmapped, 8192, IO::AIO::MREMAP_MAYMOVE |
|
|
2370 | or die "mremap: $!"; |
|
|
2371 | |
|
|
2372 | if ($success*1) { |
|
|
2373 | warn "scalar has chanegd address in memory\n"; |
|
|
2374 | } |
|
|
2375 | |
|
|
2376 | C<IO::AIO::MREMAP_FIXED> and the C<$new_address> argument are currently |
|
|
2377 | implemented, but not supported and might go away in a future version. |
|
|
2378 | |
|
|
2379 | On systems where this call is not supported or is not emulated, this call |
|
|
2380 | returns falls and sets C<$!> to C<ENOSYS>. |
|
|
2381 | |
|
|
2382 | =item IO::AIO::mlockall $flags |
|
|
2383 | |
|
|
2384 | Calls the C<eio_mlockall_sync> function, which is like C<aio_mlockall>, |
|
|
2385 | but is blocking. |
|
|
2386 | |
1697 | =item IO::AIO::munlock $scalar, $offset = 0, $length = undef |
2387 | =item IO::AIO::munlock $scalar, $offset = 0, $length = undef |
1698 | |
2388 | |
1699 | Calls the C<munlock> function, undoing the effects of a previous |
2389 | Calls the C<munlock> function, undoing the effects of a previous |
1700 | C<aio_mlock> call (see its description for details). |
2390 | C<aio_mlock> call (see its description for details). |
1701 | |
2391 | |
… | |
… | |
1703 | |
2393 | |
1704 | Calls the C<munlockall> function. |
2394 | Calls the C<munlockall> function. |
1705 | |
2395 | |
1706 | On systems that do not implement C<munlockall>, this function returns |
2396 | On systems that do not implement C<munlockall>, this function returns |
1707 | ENOSYS, otherwise the return value of C<munlockall>. |
2397 | ENOSYS, otherwise the return value of C<munlockall>. |
|
|
2398 | |
|
|
2399 | =item $fh = IO::AIO::accept4 $r_fh, $sockaddr, $sockaddr_maxlen, $flags |
|
|
2400 | |
|
|
2401 | Uses the GNU/Linux C<accept4(2)> syscall, if available, to accept a socket |
|
|
2402 | and return the new file handle on success, or sets C<$!> and returns |
|
|
2403 | C<undef> on error. |
|
|
2404 | |
|
|
2405 | The remote name of the new socket will be stored in C<$sockaddr>, which |
|
|
2406 | will be extended to allow for at least C<$sockaddr_maxlen> octets. If the |
|
|
2407 | socket name does not fit into C<$sockaddr_maxlen> octets, this is signaled |
|
|
2408 | by returning a longer string in C<$sockaddr>, which might or might not be |
|
|
2409 | truncated. |
|
|
2410 | |
|
|
2411 | To accept name-less sockets, use C<undef> for C<$sockaddr> and C<0> for |
|
|
2412 | C<$sockaddr_maxlen>. |
|
|
2413 | |
|
|
2414 | The main reasons to use this syscall rather than portable C<accept(2)> |
|
|
2415 | are that you can specify C<SOCK_NONBLOCK> and/or C<SOCK_CLOEXEC> |
|
|
2416 | flags and you can accept name-less sockets by specifying C<0> for |
|
|
2417 | C<$sockaddr_maxlen>, which is sadly not possible with perl's interface to |
|
|
2418 | C<accept>. |
|
|
2419 | |
|
|
2420 | =item IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags |
|
|
2421 | |
|
|
2422 | Calls the GNU/Linux C<splice(2)> syscall, if available. If C<$r_off> or |
|
|
2423 | C<$w_off> are C<undef>, then C<NULL> is passed for these, otherwise they |
|
|
2424 | should be the file offset. |
|
|
2425 | |
|
|
2426 | C<$r_fh> and C<$w_fh> should not refer to the same file, as splice might |
|
|
2427 | silently corrupt the data in this case. |
|
|
2428 | |
|
|
2429 | The following symbol flag values are available: C<IO::AIO::SPLICE_F_MOVE>, |
|
|
2430 | C<IO::AIO::SPLICE_F_NONBLOCK>, C<IO::AIO::SPLICE_F_MORE> and |
|
|
2431 | C<IO::AIO::SPLICE_F_GIFT>. |
|
|
2432 | |
|
|
2433 | See the C<splice(2)> manpage for details. |
|
|
2434 | |
|
|
2435 | =item IO::AIO::tee $r_fh, $w_fh, $length, $flags |
|
|
2436 | |
|
|
2437 | Calls the GNU/Linux C<tee(2)> syscall, see its manpage and the |
|
|
2438 | description for C<IO::AIO::splice> above for details. |
|
|
2439 | |
|
|
2440 | =item $actual_size = IO::AIO::pipesize $r_fh[, $new_size] |
|
|
2441 | |
|
|
2442 | Attempts to query or change the pipe buffer size. Obviously works only |
|
|
2443 | on pipes, and currently works only on GNU/Linux systems, and fails with |
|
|
2444 | C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer |
|
|
2445 | size on other systems, drop me a note. |
|
|
2446 | |
|
|
2447 | =item ($rfh, $wfh) = IO::AIO::pipe2 [$flags] |
|
|
2448 | |
|
|
2449 | This is a direct interface to the Linux L<pipe2(2)> system call. If |
|
|
2450 | C<$flags> is missing or C<0>, then this should be the same as a call to |
|
|
2451 | perl's built-in C<pipe> function and create a new pipe, and works on |
|
|
2452 | systems that lack the pipe2 syscall. On win32, this case invokes C<_pipe |
|
|
2453 | (..., 4096, O_BINARY)>. |
|
|
2454 | |
|
|
2455 | If C<$flags> is non-zero, it tries to invoke the pipe2 system call with |
|
|
2456 | the given flags (Linux 2.6.27, glibc 2.9). |
|
|
2457 | |
|
|
2458 | On success, the read and write file handles are returned. |
|
|
2459 | |
|
|
2460 | On error, nothing will be returned. If the pipe2 syscall is missing and |
|
|
2461 | C<$flags> is non-zero, fails with C<ENOSYS>. |
|
|
2462 | |
|
|
2463 | Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the |
|
|
2464 | time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and |
|
|
2465 | C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported. |
|
|
2466 | |
|
|
2467 | Example: create a pipe race-free w.r.t. threads and fork: |
|
|
2468 | |
|
|
2469 | my ($rfh, $wfh) = IO::AIO::pipe2 IO::AIO::O_CLOEXEC |
|
|
2470 | or die "pipe2: $!\n"; |
|
|
2471 | |
|
|
2472 | =item $fh = IO::AIO::memfd_create $pathname[, $flags] |
|
|
2473 | |
|
|
2474 | This is a direct interface to the Linux L<memfd_create(2)> system |
|
|
2475 | call. The (unhelpful) default for C<$flags> is C<0>, but your default |
|
|
2476 | should be C<IO::AIO::MFD_CLOEXEC>. |
|
|
2477 | |
|
|
2478 | On success, the new memfd filehandle is returned, otherwise returns |
|
|
2479 | C<undef>. If the memfd_create syscall is missing, fails with C<ENOSYS>. |
|
|
2480 | |
|
|
2481 | Please refer to L<memfd_create(2)> for more info on this call. |
|
|
2482 | |
|
|
2483 | The following C<$flags> values are available: C<IO::AIO::MFD_CLOEXEC>, |
|
|
2484 | C<IO::AIO::MFD_ALLOW_SEALING> and C<IO::AIO::MFD_HUGETLB>. |
|
|
2485 | |
|
|
2486 | Example: create a new memfd. |
|
|
2487 | |
|
|
2488 | my $fh = IO::AIO::memfd_create "somenameforprocfd", IO::AIO::MFD_CLOEXEC |
|
|
2489 | or die "memfd_create: $!\n"; |
|
|
2490 | |
|
|
2491 | =item $fh = IO::AIO::pidfd_open $pid[, $flags] |
|
|
2492 | |
|
|
2493 | This is an interface to the Linux L<pidfd_open(2)> system call. The |
|
|
2494 | default for C<$flags> is C<0>. |
|
|
2495 | |
|
|
2496 | On success, a new pidfd filehandle is returned (that is already set to |
|
|
2497 | close-on-exec), otherwise returns C<undef>. If the syscall is missing, |
|
|
2498 | fails with C<ENOSYS>. |
|
|
2499 | |
|
|
2500 | Example: open pid 6341 as pidfd. |
|
|
2501 | |
|
|
2502 | my $fh = IO::AIO::pidfd_open 6341 |
|
|
2503 | or die "pidfd_open: $!\n"; |
|
|
2504 | |
|
|
2505 | =item $status = IO::AIO::pidfd_send_signal $pidfh, $signal[, $siginfo[, $flags]] |
|
|
2506 | |
|
|
2507 | This is an interface to the Linux L<pidfd_send_signal> system call. The |
|
|
2508 | default for C<$siginfo> is C<undef> and the default for C<$flags> is C<0>. |
|
|
2509 | |
|
|
2510 | Returns the system call status. If the syscall is missing, fails with |
|
|
2511 | C<ENOSYS>. |
|
|
2512 | |
|
|
2513 | When specified, C<$siginfo> must be a reference to a hash with one or more |
|
|
2514 | of the following members: |
|
|
2515 | |
|
|
2516 | =over |
|
|
2517 | |
|
|
2518 | =item code - the C<si_code> member |
|
|
2519 | |
|
|
2520 | =item pid - the C<si_pid> member |
|
|
2521 | |
|
|
2522 | =item uid - the C<si_uid> member |
|
|
2523 | |
|
|
2524 | =item value_int - the C<si_value.sival_int> member |
|
|
2525 | |
|
|
2526 | =item value_ptr - the C<si_value.sival_ptr> member, specified as an integer |
|
|
2527 | |
|
|
2528 | =back |
|
|
2529 | |
|
|
2530 | Example: send a SIGKILL to the specified process. |
|
|
2531 | |
|
|
2532 | my $status = IO::AIO::pidfd_send_signal $pidfh, 9, undef |
|
|
2533 | and die "pidfd_send_signal: $!\n"; |
|
|
2534 | |
|
|
2535 | Example: send a SIGKILL to the specified process with extra data. |
|
|
2536 | |
|
|
2537 | my $status = IO::AIO::pidfd_send_signal $pidfh, 9, { code => -1, value_int => 7 } |
|
|
2538 | and die "pidfd_send_signal: $!\n"; |
|
|
2539 | |
|
|
2540 | =item $fh = IO::AIO::pidfd_getfd $pidfh, $targetfd[, $flags] |
|
|
2541 | |
|
|
2542 | This is an interface to the Linux L<pidfd_getfd> system call. The default |
|
|
2543 | for C<$flags> is C<0>. |
|
|
2544 | |
|
|
2545 | On success, returns a dup'ed copy of the target file descriptor (specified |
|
|
2546 | as an integer) returned (that is already set to close-on-exec), otherwise |
|
|
2547 | returns C<undef>. If the syscall is missing, fails with C<ENOSYS>. |
|
|
2548 | |
|
|
2549 | Example: get a copy of standard error of another process and print soemthing to it. |
|
|
2550 | |
|
|
2551 | my $errfh = IO::AIO::pidfd_getfd $pidfh, 2 |
|
|
2552 | or die "pidfd_getfd: $!\n"; |
|
|
2553 | print $errfh "stderr\n"; |
|
|
2554 | |
|
|
2555 | =item $fh = IO::AIO::eventfd [$initval, [$flags]] |
|
|
2556 | |
|
|
2557 | This is a direct interface to the Linux L<eventfd(2)> system call. The |
|
|
2558 | (unhelpful) defaults for C<$initval> and C<$flags> are C<0> for both. |
|
|
2559 | |
|
|
2560 | On success, the new eventfd filehandle is returned, otherwise returns |
|
|
2561 | C<undef>. If the eventfd syscall is missing, fails with C<ENOSYS>. |
|
|
2562 | |
|
|
2563 | Please refer to L<eventfd(2)> for more info on this call. |
|
|
2564 | |
|
|
2565 | The following symbol flag values are available: C<IO::AIO::EFD_CLOEXEC>, |
|
|
2566 | C<IO::AIO::EFD_NONBLOCK> and C<IO::AIO::EFD_SEMAPHORE> (Linux 2.6.30). |
|
|
2567 | |
|
|
2568 | Example: create a new eventfd filehandle: |
|
|
2569 | |
|
|
2570 | $fh = IO::AIO::eventfd 0, IO::AIO::EFD_CLOEXEC |
|
|
2571 | or die "eventfd: $!\n"; |
|
|
2572 | |
|
|
2573 | =item $fh = IO::AIO::timerfd_create $clockid[, $flags] |
|
|
2574 | |
|
|
2575 | This is a direct interface to the Linux L<timerfd_create(2)> system |
|
|
2576 | call. The (unhelpful) default for C<$flags> is C<0>, but your default |
|
|
2577 | should be C<IO::AIO::TFD_CLOEXEC>. |
|
|
2578 | |
|
|
2579 | On success, the new timerfd filehandle is returned, otherwise returns |
|
|
2580 | C<undef>. If the timerfd_create syscall is missing, fails with C<ENOSYS>. |
|
|
2581 | |
|
|
2582 | Please refer to L<timerfd_create(2)> for more info on this call. |
|
|
2583 | |
|
|
2584 | The following C<$clockid> values are |
|
|
2585 | available: C<IO::AIO::CLOCK_REALTIME>, C<IO::AIO::CLOCK_MONOTONIC> |
|
|
2586 | C<IO::AIO::CLOCK_CLOCK_BOOTTIME> (Linux 3.15) |
|
|
2587 | C<IO::AIO::CLOCK_CLOCK_REALTIME_ALARM> (Linux 3.11) and |
|
|
2588 | C<IO::AIO::CLOCK_CLOCK_BOOTTIME_ALARM> (Linux 3.11). |
|
|
2589 | |
|
|
2590 | The following C<$flags> values are available (Linux |
|
|
2591 | 2.6.27): C<IO::AIO::TFD_NONBLOCK> and C<IO::AIO::TFD_CLOEXEC>. |
|
|
2592 | |
|
|
2593 | Example: create a new timerfd and set it to one-second repeated alarms, |
|
|
2594 | then wait for two alarms: |
|
|
2595 | |
|
|
2596 | my $fh = IO::AIO::timerfd_create IO::AIO::CLOCK_BOOTTIME, IO::AIO::TFD_CLOEXEC |
|
|
2597 | or die "timerfd_create: $!\n"; |
|
|
2598 | |
|
|
2599 | defined IO::AIO::timerfd_settime $fh, 0, 1, 1 |
|
|
2600 | or die "timerfd_settime: $!\n"; |
|
|
2601 | |
|
|
2602 | for (1..2) { |
|
|
2603 | 8 == sysread $fh, my $buf, 8 |
|
|
2604 | or die "timerfd read failure\n"; |
|
|
2605 | |
|
|
2606 | printf "number of expirations (likely 1): %d\n", |
|
|
2607 | unpack "Q", $buf; |
|
|
2608 | } |
|
|
2609 | |
|
|
2610 | =item ($cur_interval, $cur_value) = IO::AIO::timerfd_settime $fh, $flags, $new_interval, $nbw_value |
|
|
2611 | |
|
|
2612 | This is a direct interface to the Linux L<timerfd_settime(2)> system |
|
|
2613 | call. Please refer to its manpage for more info on this call. |
|
|
2614 | |
|
|
2615 | The new itimerspec is specified using two (possibly fractional) second |
|
|
2616 | values, C<$new_interval> and C<$new_value>). |
|
|
2617 | |
|
|
2618 | On success, the current interval and value are returned (as per |
|
|
2619 | C<timerfd_gettime>). On failure, the empty list is returned. |
|
|
2620 | |
|
|
2621 | The following C<$flags> values are |
|
|
2622 | available: C<IO::AIO::TFD_TIMER_ABSTIME> and |
|
|
2623 | C<IO::AIO::TFD_TIMER_CANCEL_ON_SET>. |
|
|
2624 | |
|
|
2625 | See C<IO::AIO::timerfd_create> for a full example. |
|
|
2626 | |
|
|
2627 | =item ($cur_interval, $cur_value) = IO::AIO::timerfd_gettime $fh |
|
|
2628 | |
|
|
2629 | This is a direct interface to the Linux L<timerfd_gettime(2)> system |
|
|
2630 | call. Please refer to its manpage for more info on this call. |
|
|
2631 | |
|
|
2632 | On success, returns the current values of interval and value for the given |
|
|
2633 | timerfd (as potentially fractional second values). On failure, the empty |
|
|
2634 | list is returned. |
1708 | |
2635 | |
1709 | =back |
2636 | =back |
1710 | |
2637 | |
1711 | =cut |
2638 | =cut |
1712 | |
2639 | |
… | |
… | |
1747 | Danga::Socket->AddOtherFds (IO::AIO::poll_fileno => |
2674 | Danga::Socket->AddOtherFds (IO::AIO::poll_fileno => |
1748 | \&IO::AIO::poll_cb); |
2675 | \&IO::AIO::poll_cb); |
1749 | |
2676 | |
1750 | =head2 FORK BEHAVIOUR |
2677 | =head2 FORK BEHAVIOUR |
1751 | |
2678 | |
1752 | This module should do "the right thing" when the process using it forks: |
2679 | Usage of pthreads in a program changes the semantics of fork |
|
|
2680 | considerably. Specifically, only async-safe functions can be called after |
|
|
2681 | fork. Perl doesn't know about this, so in general, you cannot call fork |
|
|
2682 | with defined behaviour in perl if pthreads are involved. IO::AIO uses |
|
|
2683 | pthreads, so this applies, but many other extensions and (for inexplicable |
|
|
2684 | reasons) perl itself often is linked against pthreads, so this limitation |
|
|
2685 | applies to quite a lot of perls. |
1753 | |
2686 | |
1754 | Before the fork, IO::AIO enters a quiescent state where no requests |
2687 | This module no longer tries to fight your OS, or POSIX. That means IO::AIO |
1755 | can be added in other threads and no results will be processed. After |
2688 | only works in the process that loaded it. Forking is fully supported, but |
1756 | the fork the parent simply leaves the quiescent state and continues |
2689 | using IO::AIO in the child is not. |
1757 | request/result processing, while the child frees the request/result queue |
|
|
1758 | (so that the requests started before the fork will only be handled in the |
|
|
1759 | parent). Threads will be started on demand until the limit set in the |
|
|
1760 | parent process has been reached again. |
|
|
1761 | |
2690 | |
1762 | In short: the parent will, after a short pause, continue as if fork had |
2691 | You might get around by not I<using> IO::AIO before (or after) |
1763 | not been called, while the child will act as if IO::AIO has not been used |
2692 | forking. You could also try to call the L<IO::AIO::reinit> function in the |
1764 | yet. |
2693 | child: |
|
|
2694 | |
|
|
2695 | =over 4 |
|
|
2696 | |
|
|
2697 | =item IO::AIO::reinit |
|
|
2698 | |
|
|
2699 | Abandons all current requests and I/O threads and simply reinitialises all |
|
|
2700 | data structures. This is not an operation supported by any standards, but |
|
|
2701 | happens to work on GNU/Linux and some newer BSD systems. |
|
|
2702 | |
|
|
2703 | The only reasonable use for this function is to call it after forking, if |
|
|
2704 | C<IO::AIO> was used in the parent. Calling it while IO::AIO is active in |
|
|
2705 | the process will result in undefined behaviour. Calling it at any time |
|
|
2706 | will also result in any undefined (by POSIX) behaviour. |
|
|
2707 | |
|
|
2708 | =back |
|
|
2709 | |
|
|
2710 | =head2 LINUX-SPECIFIC CALLS |
|
|
2711 | |
|
|
2712 | When a call is documented as "linux-specific" then this means it |
|
|
2713 | originated on GNU/Linux. C<IO::AIO> will usually try to autodetect the |
|
|
2714 | availability and compatibility of such calls regardless of the platform |
|
|
2715 | it is compiled on, so platforms such as FreeBSD which often implement |
|
|
2716 | these calls will work. When in doubt, call them and see if they fail wth |
|
|
2717 | C<ENOSYS>. |
1765 | |
2718 | |
1766 | =head2 MEMORY USAGE |
2719 | =head2 MEMORY USAGE |
1767 | |
2720 | |
1768 | Per-request usage: |
2721 | Per-request usage: |
1769 | |
2722 | |
… | |
… | |
1782 | temporary buffers, and each thread requires a stack and other data |
2735 | temporary buffers, and each thread requires a stack and other data |
1783 | structures (usually around 16k-128k, depending on the OS). |
2736 | structures (usually around 16k-128k, depending on the OS). |
1784 | |
2737 | |
1785 | =head1 KNOWN BUGS |
2738 | =head1 KNOWN BUGS |
1786 | |
2739 | |
1787 | Known bugs will be fixed in the next release. |
2740 | Known bugs will be fixed in the next release :) |
|
|
2741 | |
|
|
2742 | =head1 KNOWN ISSUES |
|
|
2743 | |
|
|
2744 | Calls that try to "import" foreign memory areas (such as C<IO::AIO::mmap> |
|
|
2745 | or C<IO::AIO::aio_slurp>) do not work with generic lvalues, such as |
|
|
2746 | non-created hash slots or other scalars I didn't think of. It's best to |
|
|
2747 | avoid such and either use scalar variables or making sure that the scalar |
|
|
2748 | exists (e.g. by storing C<undef>) and isn't "funny" (e.g. tied). |
|
|
2749 | |
|
|
2750 | I am not sure anything can be done about this, so this is considered a |
|
|
2751 | known issue, rather than a bug. |
1788 | |
2752 | |
1789 | =head1 SEE ALSO |
2753 | =head1 SEE ALSO |
1790 | |
2754 | |
1791 | L<AnyEvent::AIO> for easy integration into event loops, L<Coro::AIO> for a |
2755 | L<AnyEvent::AIO> for easy integration into event loops, L<Coro::AIO> for a |
1792 | more natural syntax. |
2756 | more natural syntax and L<IO::FDPass> for file descriptor passing. |
1793 | |
2757 | |
1794 | =head1 AUTHOR |
2758 | =head1 AUTHOR |
1795 | |
2759 | |
1796 | Marc Lehmann <schmorp@schmorp.de> |
2760 | Marc Lehmann <schmorp@schmorp.de> |
1797 | http://home.schmorp.de/ |
2761 | http://home.schmorp.de/ |