1 | NAME |
1 | NAME |
2 | IO::AIO - Asynchronous Input/Output |
2 | IO::AIO - Asynchronous/Advanced Input/Output |
3 | |
3 | |
4 | SYNOPSIS |
4 | SYNOPSIS |
5 | use IO::AIO; |
5 | use IO::AIO; |
6 | |
6 | |
7 | aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub { |
7 | aio_open "/etc/passwd", IO::AIO::O_RDONLY, 0, sub { |
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55 | not well-supported or restricted (GNU/Linux doesn't allow them on normal |
55 | not well-supported or restricted (GNU/Linux doesn't allow them on normal |
56 | files currently, for example), and they would only support aio_read and |
56 | files currently, for example), and they would only support aio_read and |
57 | aio_write, so the remaining functionality would have to be implemented |
57 | aio_write, so the remaining functionality would have to be implemented |
58 | using threads anyway. |
58 | using threads anyway. |
59 | |
59 | |
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60 | In addition to asynchronous I/O, this module also exports some rather |
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61 | arcane interfaces, such as "madvise" or linux's "splice" system call, |
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62 | which is why the "A" in "AIO" can also mean *advanced*. |
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63 | |
60 | Although the module will work in the presence of other (Perl-) threads, |
64 | Although the module will work in the presence of other (Perl-) threads, |
61 | it is currently not reentrant in any way, so use appropriate locking |
65 | it is currently not reentrant in any way, so use appropriate locking |
62 | yourself, always call "poll_cb" from within the same thread, or never |
66 | yourself, always call "poll_cb" from within the same thread, or never |
63 | call "poll_cb" (or other "aio_" functions) recursively. |
67 | call "poll_cb" (or other "aio_" functions) recursively. |
64 | |
68 | |
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90 | |
94 | |
91 | # file contents now in $contents |
95 | # file contents now in $contents |
92 | print $contents; |
96 | print $contents; |
93 | |
97 | |
94 | # exit event loop and program |
98 | # exit event loop and program |
95 | EV::unloop; |
99 | EV::break; |
96 | }; |
100 | }; |
97 | }; |
101 | }; |
98 | |
102 | |
99 | # possibly queue up other requests, or open GUI windows, |
103 | # possibly queue up other requests, or open GUI windows, |
100 | # check for sockets etc. etc. |
104 | # check for sockets etc. etc. |
101 | |
105 | |
102 | # process events as long as there are some: |
106 | # process events as long as there are some: |
103 | EV::loop; |
107 | EV::run; |
104 | |
108 | |
105 | REQUEST ANATOMY AND LIFETIME |
109 | REQUEST ANATOMY AND LIFETIME |
106 | Every "aio_*" function creates a request. which is a C data structure |
110 | Every "aio_*" function creates a request. which is a C data structure |
107 | not directly visible to Perl. |
111 | not directly visible to Perl. |
108 | |
112 | |
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171 | aio_unlink $pathname, $callback->($status) |
175 | aio_unlink $pathname, $callback->($status) |
172 | aio_mknod $pathname, $mode, $dev, $callback->($status) |
176 | aio_mknod $pathname, $mode, $dev, $callback->($status) |
173 | aio_link $srcpath, $dstpath, $callback->($status) |
177 | aio_link $srcpath, $dstpath, $callback->($status) |
174 | aio_symlink $srcpath, $dstpath, $callback->($status) |
178 | aio_symlink $srcpath, $dstpath, $callback->($status) |
175 | aio_readlink $pathname, $callback->($link) |
179 | aio_readlink $pathname, $callback->($link) |
176 | aio_realpath $pathname, $callback->($link) |
180 | aio_realpath $pathname, $callback->($path) |
177 | aio_rename $srcpath, $dstpath, $callback->($status) |
181 | aio_rename $srcpath, $dstpath, $callback->($status) |
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182 | aio_rename2 $srcpath, $dstpath, $flags, $callback->($status) |
178 | aio_mkdir $pathname, $mode, $callback->($status) |
183 | aio_mkdir $pathname, $mode, $callback->($status) |
179 | aio_rmdir $pathname, $callback->($status) |
184 | aio_rmdir $pathname, $callback->($status) |
180 | aio_readdir $pathname, $callback->($entries) |
185 | aio_readdir $pathname, $callback->($entries) |
181 | aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
186 | aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
182 | IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST |
187 | IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST |
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184 | aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs) |
189 | aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs) |
185 | aio_load $pathname, $data, $callback->($status) |
190 | aio_load $pathname, $data, $callback->($status) |
186 | aio_copy $srcpath, $dstpath, $callback->($status) |
191 | aio_copy $srcpath, $dstpath, $callback->($status) |
187 | aio_move $srcpath, $dstpath, $callback->($status) |
192 | aio_move $srcpath, $dstpath, $callback->($status) |
188 | aio_rmtree $pathname, $callback->($status) |
193 | aio_rmtree $pathname, $callback->($status) |
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194 | aio_fcntl $fh, $cmd, $arg, $callback->($status) |
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195 | aio_ioctl $fh, $request, $buf, $callback->($status) |
189 | aio_sync $callback->($status) |
196 | aio_sync $callback->($status) |
190 | aio_syncfs $fh, $callback->($status) |
197 | aio_syncfs $fh, $callback->($status) |
191 | aio_fsync $fh, $callback->($status) |
198 | aio_fsync $fh, $callback->($status) |
192 | aio_fdatasync $fh, $callback->($status) |
199 | aio_fdatasync $fh, $callback->($status) |
193 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
200 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
194 | aio_pathsync $pathname, $callback->($status) |
201 | aio_pathsync $pathname, $callback->($status) |
195 | aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
202 | aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status) |
196 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
203 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
197 | aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
204 | aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
198 | aio_mlockall $flags, $callback->($status) |
205 | aio_mlockall $flags, $callback->($status) |
199 | aio_group $callback->(...) |
206 | aio_group $callback->(...) |
200 | aio_nop $callback->() |
207 | aio_nop $callback->() |
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214 | IO::AIO::idle_timeout $seconds |
221 | IO::AIO::idle_timeout $seconds |
215 | IO::AIO::max_outstanding $maxreqs |
222 | IO::AIO::max_outstanding $maxreqs |
216 | IO::AIO::nreqs |
223 | IO::AIO::nreqs |
217 | IO::AIO::nready |
224 | IO::AIO::nready |
218 | IO::AIO::npending |
225 | IO::AIO::npending |
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226 | IO::AIO::reinit |
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227 | |
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228 | $nfd = IO::AIO::get_fdlimit |
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229 | IO::AIO::min_fdlimit $nfd |
219 | |
230 | |
220 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
231 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
221 | IO::AIO::fadvise $fh, $offset, $len, $advice |
232 | IO::AIO::fadvise $fh, $offset, $len, $advice |
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233 | |
222 | IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]] |
234 | IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]] |
223 | IO::AIO::munmap $scalar |
235 | IO::AIO::munmap $scalar |
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236 | IO::AIO::mremap $scalar, $new_length, $flags[, $new_address] |
224 | IO::AIO::madvise $scalar, $offset, $length, $advice |
237 | IO::AIO::madvise $scalar, $offset, $length, $advice |
225 | IO::AIO::mprotect $scalar, $offset, $length, $protect |
238 | IO::AIO::mprotect $scalar, $offset, $length, $protect |
226 | IO::AIO::munlock $scalar, $offset = 0, $length = undef |
239 | IO::AIO::munlock $scalar, $offset = 0, $length = undef |
227 | IO::AIO::munlockall |
240 | IO::AIO::munlockall |
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241 | |
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242 | # stat extensions |
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243 | $counter = IO::AIO::st_gen |
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244 | $seconds = IO::AIO::st_atime, IO::AIO::st_mtime, IO::AIO::st_ctime, IO::AIO::st_btime |
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245 | ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtime |
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246 | $nanoseconds = IO::AIO::st_atimensec, IO::AIO::st_mtimensec, IO::AIO::st_ctimensec, IO::AIO::st_btimensec |
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247 | $seconds = IO::AIO::st_btimesec |
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248 | ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtimensec |
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249 | |
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250 | # very much unportable syscalls |
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251 | IO::AIO::accept4 $r_fh, $sockaddr, $sockaddr_len, $flags |
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252 | IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags |
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253 | IO::AIO::tee $r_fh, $w_fh, $length, $flags |
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254 | $actual_size = IO::AIO::pipesize $r_fh[, $new_size] |
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255 | ($rfh, $wfh) = IO::AIO::pipe2 [$flags] |
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256 | $fh = IO::AIO::memfd_create $pathname[, $flags] |
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257 | $fh = IO::AIO::eventfd [$initval, [$flags]] |
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258 | $fh = IO::AIO::timerfd_create $clockid[, $flags] |
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259 | ($cur_interval, $cur_value) = IO::AIO::timerfd_settime $fh, $flags, $new_interval, $nbw_value |
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260 | ($cur_interval, $cur_value) = IO::AIO::timerfd_gettime $fh |
228 | |
261 | |
229 | API NOTES |
262 | API NOTES |
230 | All the "aio_*" calls are more or less thin wrappers around the syscall |
263 | All the "aio_*" calls are more or less thin wrappers around the syscall |
231 | with the same name (sans "aio_"). The arguments are similar or |
264 | with the same name (sans "aio_"). The arguments are similar or |
232 | identical, and they all accept an additional (and optional) $callback |
265 | identical, and they all accept an additional (and optional) $callback |
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330 | "O_APPEND"), the following POSIX and non-POSIX constants are |
363 | "O_APPEND"), the following POSIX and non-POSIX constants are |
331 | available (missing ones on your system are, as usual, 0): |
364 | available (missing ones on your system are, as usual, 0): |
332 | |
365 | |
333 | "O_ASYNC", "O_DIRECT", "O_NOATIME", "O_CLOEXEC", "O_NOCTTY", |
366 | "O_ASYNC", "O_DIRECT", "O_NOATIME", "O_CLOEXEC", "O_NOCTTY", |
334 | "O_NOFOLLOW", "O_NONBLOCK", "O_EXEC", "O_SEARCH", "O_DIRECTORY", |
367 | "O_NOFOLLOW", "O_NONBLOCK", "O_EXEC", "O_SEARCH", "O_DIRECTORY", |
335 | "O_DSYNC", "O_RSYNC", "O_SYNC" and "O_TTY_INIT". |
368 | "O_DSYNC", "O_RSYNC", "O_SYNC", "O_PATH", "O_TMPFILE", "O_TTY_INIT" |
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369 | and "O_ACCMODE". |
336 | |
370 | |
337 | aio_close $fh, $callback->($status) |
371 | aio_close $fh, $callback->($status) |
338 | Asynchronously close a file and call the callback with the result |
372 | Asynchronously close a file and call the callback with the result |
339 | code. |
373 | code. |
340 | |
374 | |
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370 | |
404 | |
371 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
405 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
372 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
406 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
373 | Reads or writes $length bytes from or to the specified $fh and |
407 | Reads or writes $length bytes from or to the specified $fh and |
374 | $offset into the scalar given by $data and offset $dataoffset and |
408 | $offset into the scalar given by $data and offset $dataoffset and |
375 | calls the callback without the actual number of bytes read (or -1 on |
409 | calls the callback with the actual number of bytes transferred (or |
376 | error, just like the syscall). |
410 | -1 on error, just like the syscall). |
377 | |
411 | |
378 | "aio_read" will, like "sysread", shrink or grow the $data scalar to |
412 | "aio_read" will, like "sysread", shrink or grow the $data scalar to |
379 | offset plus the actual number of bytes read. |
413 | offset plus the actual number of bytes read. |
380 | |
414 | |
381 | If $offset is undefined, then the current file descriptor offset |
415 | If $offset is undefined, then the current file descriptor offset |
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438 | As native sendfile syscalls (as practically any non-POSIX interface |
472 | As native sendfile syscalls (as practically any non-POSIX interface |
439 | hacked together in a hurry to improve benchmark numbers) tend to be |
473 | hacked together in a hurry to improve benchmark numbers) tend to be |
440 | rather buggy on many systems, this implementation tries to work |
474 | rather buggy on many systems, this implementation tries to work |
441 | around some known bugs in Linux and FreeBSD kernels (probably |
475 | around some known bugs in Linux and FreeBSD kernels (probably |
442 | others, too), but that might fail, so you really really should check |
476 | others, too), but that might fail, so you really really should check |
443 | the return value of "aio_sendfile" - fewre bytes than expected might |
477 | the return value of "aio_sendfile" - fewer bytes than expected might |
444 | have been transferred. |
478 | have been transferred. |
445 | |
479 | |
446 | aio_readahead $fh,$offset,$length, $callback->($retval) |
480 | aio_readahead $fh,$offset,$length, $callback->($retval) |
447 | "aio_readahead" populates the page cache with data from a file so |
481 | "aio_readahead" populates the page cache with data from a file so |
448 | that subsequent reads from that file will not block on disk I/O. The |
482 | that subsequent reads from that file will not block on disk I/O. The |
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452 | to a page boundary and bytes are read up to the next page boundary |
486 | to a page boundary and bytes are read up to the next page boundary |
453 | greater than or equal to (off-set+length). "aio_readahead" does not |
487 | greater than or equal to (off-set+length). "aio_readahead" does not |
454 | read beyond the end of the file. The current file offset of the file |
488 | read beyond the end of the file. The current file offset of the file |
455 | is left unchanged. |
489 | is left unchanged. |
456 | |
490 | |
457 | If that syscall doesn't exist (likely if your OS isn't Linux) it |
491 | If that syscall doesn't exist (likely if your kernel isn't Linux) it |
458 | will be emulated by simply reading the data, which would have a |
492 | will be emulated by simply reading the data, which would have a |
459 | similar effect. |
493 | similar effect. |
460 | |
494 | |
461 | aio_stat $fh_or_path, $callback->($status) |
495 | aio_stat $fh_or_path, $callback->($status) |
462 | aio_lstat $fh, $callback->($status) |
496 | aio_lstat $fh, $callback->($status) |
463 | Works like perl's "stat" or "lstat" in void context. The callback |
497 | Works almost exactly like perl's "stat" or "lstat" in void context. |
464 | will be called after the stat and the results will be available |
498 | The callback will be called after the stat and the results will be |
465 | using "stat _" or "-s _" etc... |
499 | available using "stat _" or "-s _" and other tests (with the |
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500 | exception of "-B" and "-T"). |
466 | |
501 | |
467 | The pathname passed to "aio_stat" must be absolute. See API NOTES, |
502 | The pathname passed to "aio_stat" must be absolute. See API NOTES, |
468 | above, for an explanation. |
503 | above, for an explanation. |
469 | |
504 | |
470 | Currently, the stats are always 64-bit-stats, i.e. instead of |
505 | Currently, the stats are always 64-bit-stats, i.e. instead of |
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478 | back on traditional behaviour). |
513 | back on traditional behaviour). |
479 | |
514 | |
480 | "S_IFMT", "S_IFIFO", "S_IFCHR", "S_IFBLK", "S_IFLNK", "S_IFREG", |
515 | "S_IFMT", "S_IFIFO", "S_IFCHR", "S_IFBLK", "S_IFLNK", "S_IFREG", |
481 | "S_IFDIR", "S_IFWHT", "S_IFSOCK", "IO::AIO::major $dev_t", |
516 | "S_IFDIR", "S_IFWHT", "S_IFSOCK", "IO::AIO::major $dev_t", |
482 | "IO::AIO::minor $dev_t", "IO::AIO::makedev $major, $minor". |
517 | "IO::AIO::minor $dev_t", "IO::AIO::makedev $major, $minor". |
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518 | |
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519 | To access higher resolution stat timestamps, see "SUBSECOND STAT |
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520 | TIME ACCESS". |
483 | |
521 | |
484 | Example: Print the length of /etc/passwd: |
522 | Example: Print the length of /etc/passwd: |
485 | |
523 | |
486 | aio_stat "/etc/passwd", sub { |
524 | aio_stat "/etc/passwd", sub { |
487 | $_[0] and die "stat failed: $!"; |
525 | $_[0] and die "stat failed: $!"; |
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529 | namemax => 255, |
567 | namemax => 255, |
530 | frsize => 1024, |
568 | frsize => 1024, |
531 | fsid => 1810 |
569 | fsid => 1810 |
532 | } |
570 | } |
533 | |
571 | |
534 | Here is a (likely partial - send me updates!) list of fsid values |
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535 | used by Linux - it is safe to hardcode these when $^O is "linux": |
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536 | |
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537 | 0x0000adf5 adfs |
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538 | 0x0000adff affs |
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539 | 0x5346414f afs |
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540 | 0x09041934 anon-inode filesystem |
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541 | 0x00000187 autofs |
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542 | 0x42465331 befs |
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543 | 0x1badface bfs |
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544 | 0x42494e4d binfmt_misc |
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545 | 0x9123683e btrfs |
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546 | 0x0027e0eb cgroupfs |
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547 | 0xff534d42 cifs |
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548 | 0x73757245 coda |
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549 | 0x012ff7b7 coh |
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550 | 0x28cd3d45 cramfs |
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551 | 0x453dcd28 cramfs-wend (wrong endianness) |
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552 | 0x64626720 debugfs |
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553 | 0x00001373 devfs |
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554 | 0x00001cd1 devpts |
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555 | 0x0000f15f ecryptfs |
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556 | 0x00414a53 efs |
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557 | 0x0000137d ext |
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558 | 0x0000ef53 ext2/ext3 |
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559 | 0x0000ef51 ext2 |
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560 | 0x00004006 fat |
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561 | 0x65735546 fuseblk |
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562 | 0x65735543 fusectl |
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563 | 0x0bad1dea futexfs |
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564 | 0x01161970 gfs2 |
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565 | 0x47504653 gpfs |
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566 | 0x00004244 hfs |
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567 | 0xf995e849 hpfs |
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568 | 0x958458f6 hugetlbfs |
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569 | 0x2bad1dea inotifyfs |
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570 | 0x00009660 isofs |
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571 | 0x000072b6 jffs2 |
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572 | 0x3153464a jfs |
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573 | 0x6b414653 k-afs |
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574 | 0x0bd00bd0 lustre |
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575 | 0x0000137f minix |
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576 | 0x0000138f minix 30 char names |
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577 | 0x00002468 minix v2 |
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578 | 0x00002478 minix v2 30 char names |
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579 | 0x00004d5a minix v3 |
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580 | 0x19800202 mqueue |
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581 | 0x00004d44 msdos |
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582 | 0x0000564c novell |
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583 | 0x00006969 nfs |
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584 | 0x6e667364 nfsd |
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585 | 0x00003434 nilfs |
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586 | 0x5346544e ntfs |
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587 | 0x00009fa1 openprom |
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588 | 0x7461636F ocfs2 |
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589 | 0x00009fa0 proc |
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590 | 0x6165676c pstorefs |
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591 | 0x0000002f qnx4 |
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592 | 0x858458f6 ramfs |
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593 | 0x52654973 reiserfs |
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594 | 0x00007275 romfs |
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595 | 0x67596969 rpc_pipefs |
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596 | 0x73636673 securityfs |
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597 | 0xf97cff8c selinux |
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598 | 0x0000517b smb |
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599 | 0x534f434b sockfs |
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600 | 0x73717368 squashfs |
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601 | 0x62656572 sysfs |
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602 | 0x012ff7b6 sysv2 |
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603 | 0x012ff7b5 sysv4 |
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604 | 0x01021994 tmpfs |
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605 | 0x15013346 udf |
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606 | 0x00011954 ufs |
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607 | 0x54190100 ufs byteswapped |
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608 | 0x00009fa2 usbdevfs |
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609 | 0x01021997 v9fs |
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610 | 0xa501fcf5 vxfs |
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611 | 0xabba1974 xenfs |
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612 | 0x012ff7b4 xenix |
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613 | 0x58465342 xfs |
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614 | 0x012fd16d xia |
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615 | |
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616 | aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
572 | aio_utime $fh_or_path, $atime, $mtime, $callback->($status) |
617 | Works like perl's "utime" function (including the special case of |
573 | Works like perl's "utime" function (including the special case of |
618 | $atime and $mtime being undef). Fractional times are supported if |
574 | $atime and $mtime being undef). Fractional times are supported if |
619 | the underlying syscalls support them. |
575 | the underlying syscalls support them. |
620 | |
576 | |
621 | When called with a pathname, uses utimes(2) if available, otherwise |
577 | When called with a pathname, uses utimensat(2) or utimes(2) if |
622 | utime(2). If called on a file descriptor, uses futimes(2) if |
578 | available, otherwise utime(2). If called on a file descriptor, uses |
623 | available, otherwise returns ENOSYS, so this is not portable. |
579 | futimens(2) or futimes(2) if available, otherwise returns ENOSYS, so |
|
|
580 | this is not portable. |
624 | |
581 | |
625 | Examples: |
582 | Examples: |
626 | |
583 | |
627 | # set atime and mtime to current time (basically touch(1)): |
584 | # set atime and mtime to current time (basically touch(1)): |
628 | aio_utime "path", undef, undef; |
585 | aio_utime "path", undef, undef; |
… | |
… | |
643 | |
600 | |
644 | aio_truncate $fh_or_path, $offset, $callback->($status) |
601 | aio_truncate $fh_or_path, $offset, $callback->($status) |
645 | Works like truncate(2) or ftruncate(2). |
602 | Works like truncate(2) or ftruncate(2). |
646 | |
603 | |
647 | aio_allocate $fh, $mode, $offset, $len, $callback->($status) |
604 | aio_allocate $fh, $mode, $offset, $len, $callback->($status) |
648 | Allocates or freed disk space according to the $mode argument. See |
605 | Allocates or frees disk space according to the $mode argument. See |
649 | the linux "fallocate" docuemntation for details. |
606 | the linux "fallocate" documentation for details. |
650 | |
607 | |
651 | $mode can currently be 0 or "IO::AIO::FALLOC_FL_KEEP_SIZE" to |
608 | $mode is usually 0 or "IO::AIO::FALLOC_FL_KEEP_SIZE" to allocate |
652 | allocate space, or "IO::AIO::FALLOC_FL_PUNCH_HOLE | |
609 | space, or "IO::AIO::FALLOC_FL_PUNCH_HOLE | |
653 | IO::AIO::FALLOC_FL_KEEP_SIZE", to deallocate a file range. |
610 | IO::AIO::FALLOC_FL_KEEP_SIZE", to deallocate a file range. |
654 | |
611 | |
|
|
612 | IO::AIO also supports "FALLOC_FL_COLLAPSE_RANGE", to remove a range |
|
|
613 | (without leaving a hole), "FALLOC_FL_ZERO_RANGE", to zero a range, |
|
|
614 | "FALLOC_FL_INSERT_RANGE" to insert a range and |
|
|
615 | "FALLOC_FL_UNSHARE_RANGE" to unshare shared blocks (see your |
|
|
616 | fallocate(2) manpage). |
|
|
617 | |
655 | The file system block size used by "fallocate" is presumably the |
618 | The file system block size used by "fallocate" is presumably the |
656 | "f_bsize" returned by "statvfs". |
619 | "f_bsize" returned by "statvfs", but different filesystems and |
|
|
620 | filetypes can dictate other limitations. |
657 | |
621 | |
658 | If "fallocate" isn't available or cannot be emulated (currently no |
622 | If "fallocate" isn't available or cannot be emulated (currently no |
659 | emulation will be attempted), passes -1 and sets $! to "ENOSYS". |
623 | emulation will be attempted), passes -1 and sets $! to "ENOSYS". |
660 | |
624 | |
661 | aio_chmod $fh_or_path, $mode, $callback->($status) |
625 | aio_chmod $fh_or_path, $mode, $callback->($status) |
… | |
… | |
705 | |
669 | |
706 | On systems that support the AIO::WD working directory abstraction |
670 | On systems that support the AIO::WD working directory abstraction |
707 | natively, the case "[$wd, "."]" as $srcpath is specialcased - |
671 | natively, the case "[$wd, "."]" as $srcpath is specialcased - |
708 | instead of failing, "rename" is called on the absolute path of $wd. |
672 | instead of failing, "rename" is called on the absolute path of $wd. |
709 | |
673 | |
|
|
674 | aio_rename2 $srcpath, $dstpath, $flags, $callback->($status) |
|
|
675 | Basically a version of "aio_rename" with an additional $flags |
|
|
676 | argument. Calling this with "$flags=0" is the same as calling |
|
|
677 | "aio_rename". |
|
|
678 | |
|
|
679 | Non-zero flags are currently only supported on GNU/Linux systems |
|
|
680 | that support renameat2. Other systems fail with "ENOSYS" in this |
|
|
681 | case. |
|
|
682 | |
|
|
683 | The following constants are available (missing ones are, as usual |
|
|
684 | 0), see renameat2(2) for details: |
|
|
685 | |
|
|
686 | "IO::AIO::RENAME_NOREPLACE", "IO::AIO::RENAME_EXCHANGE" and |
|
|
687 | "IO::AIO::RENAME_WHITEOUT". |
|
|
688 | |
710 | aio_mkdir $pathname, $mode, $callback->($status) |
689 | aio_mkdir $pathname, $mode, $callback->($status) |
711 | Asynchronously mkdir (create) a directory and call the callback with |
690 | Asynchronously mkdir (create) a directory and call the callback with |
712 | the result code. $mode will be modified by the umask at the time the |
691 | the result code. $mode will be modified by the umask at the time the |
713 | request is executed, so do not change your umask. |
692 | request is executed, so do not change your umask. |
714 | |
693 | |
… | |
… | |
736 | The flags are a combination of the following constants, ORed |
715 | The flags are a combination of the following constants, ORed |
737 | together (the flags will also be passed to the callback, possibly |
716 | together (the flags will also be passed to the callback, possibly |
738 | modified): |
717 | modified): |
739 | |
718 | |
740 | IO::AIO::READDIR_DENTS |
719 | IO::AIO::READDIR_DENTS |
741 | When this flag is off, then the callback gets an arrayref |
720 | Normally the callback gets an arrayref consisting of names only |
742 | consisting of names only (as with "aio_readdir"), otherwise it |
721 | (as with "aio_readdir"). If this flag is set, then the callback |
743 | gets an arrayref with "[$name, $type, $inode]" arrayrefs, each |
722 | gets an arrayref with "[$name, $type, $inode]" arrayrefs, each |
744 | describing a single directory entry in more detail. |
723 | describing a single directory entry in more detail: |
745 | |
724 | |
746 | $name is the name of the entry. |
725 | $name is the name of the entry. |
747 | |
726 | |
748 | $type is one of the "IO::AIO::DT_xxx" constants: |
727 | $type is one of the "IO::AIO::DT_xxx" constants: |
749 | |
728 | |
750 | "IO::AIO::DT_UNKNOWN", "IO::AIO::DT_FIFO", "IO::AIO::DT_CHR", |
729 | "IO::AIO::DT_UNKNOWN", "IO::AIO::DT_FIFO", "IO::AIO::DT_CHR", |
751 | "IO::AIO::DT_DIR", "IO::AIO::DT_BLK", "IO::AIO::DT_REG", |
730 | "IO::AIO::DT_DIR", "IO::AIO::DT_BLK", "IO::AIO::DT_REG", |
752 | "IO::AIO::DT_LNK", "IO::AIO::DT_SOCK", "IO::AIO::DT_WHT". |
731 | "IO::AIO::DT_LNK", "IO::AIO::DT_SOCK", "IO::AIO::DT_WHT". |
753 | |
732 | |
754 | "IO::AIO::DT_UNKNOWN" means just that: readdir does not know. If |
733 | "IO::AIO::DT_UNKNOWN" means just that: readdir does not know. If |
755 | you need to know, you have to run stat yourself. Also, for speed |
734 | you need to know, you have to run stat yourself. Also, for |
756 | reasons, the $type scalars are read-only: you can not modify |
735 | speed/memory reasons, the $type scalars are read-only: you must |
757 | them. |
736 | not modify them. |
758 | |
737 | |
759 | $inode is the inode number (which might not be exact on systems |
738 | $inode is the inode number (which might not be exact on systems |
760 | with 64 bit inode numbers and 32 bit perls). This field has |
739 | with 64 bit inode numbers and 32 bit perls). This field has |
761 | unspecified content on systems that do not deliver the inode |
740 | unspecified content on systems that do not deliver the inode |
762 | information. |
741 | information. |
… | |
… | |
774 | of which names with short names are tried first. |
753 | of which names with short names are tried first. |
775 | |
754 | |
776 | IO::AIO::READDIR_STAT_ORDER |
755 | IO::AIO::READDIR_STAT_ORDER |
777 | When this flag is set, then the names will be returned in an |
756 | When this flag is set, then the names will be returned in an |
778 | order suitable for stat()'ing each one. That is, when you plan |
757 | order suitable for stat()'ing each one. That is, when you plan |
779 | to stat() all files in the given directory, then the returned |
758 | to stat() most or all files in the given directory, then the |
780 | order will likely be fastest. |
759 | returned order will likely be faster. |
781 | |
760 | |
782 | If both this flag and "IO::AIO::READDIR_DIRS_FIRST" are |
761 | If both this flag and "IO::AIO::READDIR_DIRS_FIRST" are |
783 | specified, then the likely dirs come first, resulting in a less |
762 | specified, then the likely dirs come first, resulting in a less |
784 | optimal stat order. |
763 | optimal stat order for stat'ing all entries, but likely a more |
|
|
764 | optimal order for finding subdirectories. |
785 | |
765 | |
786 | IO::AIO::READDIR_FOUND_UNKNOWN |
766 | IO::AIO::READDIR_FOUND_UNKNOWN |
787 | This flag should not be set when calling "aio_readdirx". |
767 | This flag should not be set when calling "aio_readdirx". |
788 | Instead, it is being set by "aio_readdirx", when any of the |
768 | Instead, it is being set by "aio_readdirx", when any of the |
789 | $type's found were "IO::AIO::DT_UNKNOWN". The absence of this |
769 | $type's found were "IO::AIO::DT_UNKNOWN". The absence of this |
790 | flag therefore indicates that all $type's are known, which can |
770 | flag therefore indicates that all $type's are known, which can |
791 | be used to speed up some algorithms. |
771 | be used to speed up some algorithms. |
792 | |
772 | |
|
|
773 | aio_slurp $pathname, $offset, $length, $data, $callback->($status) |
|
|
774 | Opens, reads and closes the given file. The data is put into $data, |
|
|
775 | which is resized as required. |
|
|
776 | |
|
|
777 | If $offset is negative, then it is counted from the end of the file. |
|
|
778 | |
|
|
779 | If $length is zero, then the remaining length of the file is used. |
|
|
780 | Also, in this case, the same limitations to modifying $data apply as |
|
|
781 | when IO::AIO::mmap is used, i.e. it must only be modified in-place |
|
|
782 | with "substr". If the size of the file is known, specifying a |
|
|
783 | non-zero $length results in a performance advantage. |
|
|
784 | |
|
|
785 | This request is similar to the older "aio_load" request, but since |
|
|
786 | it is a single request, it might be more efficient to use. |
|
|
787 | |
|
|
788 | Example: load /etc/passwd into $passwd. |
|
|
789 | |
|
|
790 | my $passwd; |
|
|
791 | aio_slurp "/etc/passwd", 0, 0, $passwd, sub { |
|
|
792 | $_[0] >= 0 |
|
|
793 | or die "/etc/passwd: $!\n"; |
|
|
794 | |
|
|
795 | printf "/etc/passwd is %d bytes long, and contains:\n", length $passwd; |
|
|
796 | print $passwd; |
|
|
797 | }; |
|
|
798 | IO::AIO::flush; |
|
|
799 | |
793 | aio_load $pathname, $data, $callback->($status) |
800 | aio_load $pathname, $data, $callback->($status) |
794 | This is a composite request that tries to fully load the given file |
801 | This is a composite request that tries to fully load the given file |
795 | into memory. Status is the same as with aio_read. |
802 | into memory. Status is the same as with aio_read. |
|
|
803 | |
|
|
804 | Using "aio_slurp" might be more efficient, as it is a single |
|
|
805 | request. |
796 | |
806 | |
797 | aio_copy $srcpath, $dstpath, $callback->($status) |
807 | aio_copy $srcpath, $dstpath, $callback->($status) |
798 | Try to copy the *file* (directories not supported as either source |
808 | Try to copy the *file* (directories not supported as either source |
799 | or destination) from $srcpath to $dstpath and call the callback with |
809 | or destination) from $srcpath to $dstpath and call the callback with |
800 | a status of 0 (ok) or -1 (error, see $!). |
810 | a status of 0 (ok) or -1 (error, see $!). |
|
|
811 | |
|
|
812 | Existing destination files will be truncated. |
801 | |
813 | |
802 | This is a composite request that creates the destination file with |
814 | This is a composite request that creates the destination file with |
803 | mode 0200 and copies the contents of the source file into it using |
815 | mode 0200 and copies the contents of the source file into it using |
804 | "aio_sendfile", followed by restoring atime, mtime, access mode and |
816 | "aio_sendfile", followed by restoring atime, mtime, access mode and |
805 | uid/gid, in that order. |
817 | uid/gid, in that order. |
… | |
… | |
822 | to efficiently separate the entries of directory $path into two sets |
834 | to efficiently separate the entries of directory $path into two sets |
823 | of names, directories you can recurse into (directories), and ones |
835 | of names, directories you can recurse into (directories), and ones |
824 | you cannot recurse into (everything else, including symlinks to |
836 | you cannot recurse into (everything else, including symlinks to |
825 | directories). |
837 | directories). |
826 | |
838 | |
827 | "aio_scandir" is a composite request that creates of many sub |
839 | "aio_scandir" is a composite request that generates many sub |
828 | requests_ $maxreq specifies the maximum number of outstanding aio |
840 | requests. $maxreq specifies the maximum number of outstanding aio |
829 | requests that this function generates. If it is "<= 0", then a |
841 | requests that this function generates. If it is "<= 0", then a |
830 | suitable default will be chosen (currently 4). |
842 | suitable default will be chosen (currently 4). |
831 | |
843 | |
832 | On error, the callback is called without arguments, otherwise it |
844 | On error, the callback is called without arguments, otherwise it |
833 | receives two array-refs with path-relative entry names. |
845 | receives two array-refs with path-relative entry names. |
… | |
… | |
880 | Delete a directory tree starting (and including) $path, return the |
892 | Delete a directory tree starting (and including) $path, return the |
881 | status of the final "rmdir" only. This is a composite request that |
893 | status of the final "rmdir" only. This is a composite request that |
882 | uses "aio_scandir" to recurse into and rmdir directories, and unlink |
894 | uses "aio_scandir" to recurse into and rmdir directories, and unlink |
883 | everything else. |
895 | everything else. |
884 | |
896 | |
|
|
897 | aio_fcntl $fh, $cmd, $arg, $callback->($status) |
|
|
898 | aio_ioctl $fh, $request, $buf, $callback->($status) |
|
|
899 | These work just like the "fcntl" and "ioctl" built-in functions, |
|
|
900 | except they execute asynchronously and pass the return value to the |
|
|
901 | callback. |
|
|
902 | |
|
|
903 | Both calls can be used for a lot of things, some of which make more |
|
|
904 | sense to run asynchronously in their own thread, while some others |
|
|
905 | make less sense. For example, calls that block waiting for external |
|
|
906 | events, such as locking, will also lock down an I/O thread while it |
|
|
907 | is waiting, which can deadlock the whole I/O system. At the same |
|
|
908 | time, there might be no alternative to using a thread to wait. |
|
|
909 | |
|
|
910 | So in general, you should only use these calls for things that do |
|
|
911 | (filesystem) I/O, not for things that wait for other events |
|
|
912 | (network, other processes), although if you are careful and know |
|
|
913 | what you are doing, you still can. |
|
|
914 | |
|
|
915 | The following constants are available and can be used for normal |
|
|
916 | "ioctl" and "fcntl" as well (missing ones are, as usual 0): |
|
|
917 | |
|
|
918 | "F_DUPFD_CLOEXEC", |
|
|
919 | |
|
|
920 | "F_OFD_GETLK", "F_OFD_SETLK", "F_OFD_GETLKW", |
|
|
921 | |
|
|
922 | "FIFREEZE", "FITHAW", "FITRIM", "FICLONE", "FICLONERANGE", |
|
|
923 | "FIDEDUPERANGE". |
|
|
924 | |
|
|
925 | "F_ADD_SEALS", "F_GET_SEALS", "F_SEAL_SEAL", "F_SEAL_SHRINK", |
|
|
926 | "F_SEAL_GROW" and "F_SEAL_WRITE". |
|
|
927 | |
|
|
928 | "FS_IOC_GETFLAGS", "FS_IOC_SETFLAGS", "FS_IOC_GETVERSION", |
|
|
929 | "FS_IOC_SETVERSION", "FS_IOC_FIEMAP". |
|
|
930 | |
|
|
931 | "FS_IOC_FSGETXATTR", "FS_IOC_FSSETXATTR", |
|
|
932 | "FS_IOC_SET_ENCRYPTION_POLICY", "FS_IOC_GET_ENCRYPTION_PWSALT", |
|
|
933 | "FS_IOC_GET_ENCRYPTION_POLICY", "FS_KEY_DESCRIPTOR_SIZE". |
|
|
934 | |
|
|
935 | "FS_SECRM_FL", "FS_UNRM_FL", "FS_COMPR_FL", "FS_SYNC_FL", |
|
|
936 | "FS_IMMUTABLE_FL", "FS_APPEND_FL", "FS_NODUMP_FL", "FS_NOATIME_FL", |
|
|
937 | "FS_DIRTY_FL", "FS_COMPRBLK_FL", "FS_NOCOMP_FL", "FS_ENCRYPT_FL", |
|
|
938 | "FS_BTREE_FL", "FS_INDEX_FL", "FS_JOURNAL_DATA_FL", "FS_NOTAIL_FL", |
|
|
939 | "FS_DIRSYNC_FL", "FS_TOPDIR_FL", "FS_FL_USER_MODIFIABLE". |
|
|
940 | |
|
|
941 | "FS_XFLAG_REALTIME", "FS_XFLAG_PREALLOC", "FS_XFLAG_IMMUTABLE", |
|
|
942 | "FS_XFLAG_APPEND", "FS_XFLAG_SYNC", "FS_XFLAG_NOATIME", |
|
|
943 | "FS_XFLAG_NODUMP", "FS_XFLAG_RTINHERIT", "FS_XFLAG_PROJINHERIT", |
|
|
944 | "FS_XFLAG_NOSYMLINKS", "FS_XFLAG_EXTSIZE", "FS_XFLAG_EXTSZINHERIT", |
|
|
945 | "FS_XFLAG_NODEFRAG", "FS_XFLAG_FILESTREAM", "FS_XFLAG_DAX", |
|
|
946 | "FS_XFLAG_HASATTR", |
|
|
947 | |
885 | aio_sync $callback->($status) |
948 | aio_sync $callback->($status) |
886 | Asynchronously call sync and call the callback when finished. |
949 | Asynchronously call sync and call the callback when finished. |
887 | |
950 | |
888 | aio_fsync $fh, $callback->($status) |
951 | aio_fsync $fh, $callback->($status) |
889 | Asynchronously call fsync on the given filehandle and call the |
952 | Asynchronously call fsync on the given filehandle and call the |
… | |
… | |
925 | Future versions of this function might fall back to other methods |
988 | Future versions of this function might fall back to other methods |
926 | when "fsync" on the directory fails (such as calling "sync"). |
989 | when "fsync" on the directory fails (such as calling "sync"). |
927 | |
990 | |
928 | Passes 0 when everything went ok, and -1 on error. |
991 | Passes 0 when everything went ok, and -1 on error. |
929 | |
992 | |
930 | aio_msync $scalar, $offset = 0, $length = undef, flags = 0, |
993 | aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, |
931 | $callback->($status) |
994 | $callback->($status) |
932 | This is a rather advanced IO::AIO call, which only works on |
995 | This is a rather advanced IO::AIO call, which only works on |
933 | mmap(2)ed scalars (see the "IO::AIO::mmap" function, although it |
996 | mmap(2)ed scalars (see the "IO::AIO::mmap" function, although it |
934 | also works on data scalars managed by the Sys::Mmap or Mmap modules, |
997 | also works on data scalars managed by the Sys::Mmap or Mmap modules, |
935 | note that the scalar must only be modified in-place while an aio |
998 | note that the scalar must only be modified in-place while an aio |
… | |
… | |
937 | |
1000 | |
938 | It calls the "msync" function of your OS, if available, with the |
1001 | It calls the "msync" function of your OS, if available, with the |
939 | memory area starting at $offset in the string and ending $length |
1002 | memory area starting at $offset in the string and ending $length |
940 | bytes later. If $length is negative, counts from the end, and if |
1003 | bytes later. If $length is negative, counts from the end, and if |
941 | $length is "undef", then it goes till the end of the string. The |
1004 | $length is "undef", then it goes till the end of the string. The |
942 | flags can be a combination of "IO::AIO::MS_ASYNC", |
1005 | flags can be either "IO::AIO::MS_ASYNC" or "IO::AIO::MS_SYNC", plus |
943 | "IO::AIO::MS_INVALIDATE" and "IO::AIO::MS_SYNC". |
1006 | an optional "IO::AIO::MS_INVALIDATE". |
944 | |
1007 | |
945 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, |
1008 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, |
946 | $callback->($status) |
1009 | $callback->($status) |
947 | This is a rather advanced IO::AIO call, which works best on |
1010 | This is a rather advanced IO::AIO call, which works best on |
948 | mmap(2)ed scalars. |
1011 | mmap(2)ed scalars. |
… | |
… | |
979 | IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh; |
1042 | IO::AIO::mmap $data, -s $fh, IO::AIO::PROT_READ, IO::AIO::MAP_SHARED, $fh; |
980 | aio_mlock $data; # mlock in background |
1043 | aio_mlock $data; # mlock in background |
981 | |
1044 | |
982 | aio_mlockall $flags, $callback->($status) |
1045 | aio_mlockall $flags, $callback->($status) |
983 | Calls the "mlockall" function with the given $flags (a combination |
1046 | Calls the "mlockall" function with the given $flags (a combination |
984 | of "IO::AIO::MCL_CURRENT" and "IO::AIO::MCL_FUTURE"). |
1047 | of "IO::AIO::MCL_CURRENT", "IO::AIO::MCL_FUTURE" and |
|
|
1048 | "IO::AIO::MCL_ONFAULT"). |
985 | |
1049 | |
986 | On systems that do not implement "mlockall", this function returns |
1050 | On systems that do not implement "mlockall", this function returns |
987 | -1 and sets errno to "ENOSYS". |
1051 | -1 and sets errno to "ENOSYS". Similarly, flag combinations not |
|
|
1052 | supported by the system result in a return value of -1 with errno |
|
|
1053 | being set to "EINVAL". |
988 | |
1054 | |
989 | Note that the corresponding "munlockall" is synchronous and is |
1055 | Note that the corresponding "munlockall" is synchronous and is |
990 | documented under "MISCELLANEOUS FUNCTIONS". |
1056 | documented under "MISCELLANEOUS FUNCTIONS". |
991 | |
1057 | |
992 | Example: asynchronously lock all current and future pages into |
1058 | Example: asynchronously lock all current and future pages into |
… | |
… | |
1034 | "IO::AIO::FIEMAP_EXTENT_DATA_INLINE", |
1100 | "IO::AIO::FIEMAP_EXTENT_DATA_INLINE", |
1035 | "IO::AIO::FIEMAP_EXTENT_DATA_TAIL", |
1101 | "IO::AIO::FIEMAP_EXTENT_DATA_TAIL", |
1036 | "IO::AIO::FIEMAP_EXTENT_UNWRITTEN", "IO::AIO::FIEMAP_EXTENT_MERGED" |
1102 | "IO::AIO::FIEMAP_EXTENT_UNWRITTEN", "IO::AIO::FIEMAP_EXTENT_MERGED" |
1037 | or "IO::AIO::FIEMAP_EXTENT_SHARED". |
1103 | or "IO::AIO::FIEMAP_EXTENT_SHARED". |
1038 | |
1104 | |
1039 | At the time of this writing (Linux 3.2), this requets is unreliable |
1105 | At the time of this writing (Linux 3.2), this request is unreliable |
1040 | unless $count is "undef", as the kernel has all sorts of bugs |
1106 | unless $count is "undef", as the kernel has all sorts of bugs |
1041 | preventing it to return all extents of a range for files with large |
1107 | preventing it to return all extents of a range for files with a |
1042 | number of extents. The code works around all these issues if $count |
1108 | large number of extents. The code (only) works around all these |
1043 | is undef. |
1109 | issues if $count is "undef". |
1044 | |
1110 | |
1045 | aio_group $callback->(...) |
1111 | aio_group $callback->(...) |
1046 | This is a very special aio request: Instead of doing something, it |
1112 | This is a very special aio request: Instead of doing something, it |
1047 | is a container for other aio requests, which is useful if you want |
1113 | is a container for other aio requests, which is useful if you want |
1048 | to bundle many requests into a single, composite, request with a |
1114 | to bundle many requests into a single, composite, request with a |
… | |
… | |
1128 | aio_stat [$etcdir, "passwd"], sub { |
1194 | aio_stat [$etcdir, "passwd"], sub { |
1129 | # yay |
1195 | # yay |
1130 | }; |
1196 | }; |
1131 | }; |
1197 | }; |
1132 | |
1198 | |
1133 | That "aio_wd" is a request and not a normal function shows that creating |
1199 | The fact that "aio_wd" is a request and not a normal function shows that |
1134 | an IO::AIO::WD object is itself a potentially blocking operation, which |
1200 | creating an IO::AIO::WD object is itself a potentially blocking |
1135 | is why it is done asynchronously. |
1201 | operation, which is why it is done asynchronously. |
1136 | |
1202 | |
1137 | To stat the directory obtained with "aio_wd" above, one could write |
1203 | To stat the directory obtained with "aio_wd" above, one could write |
1138 | either of the following three request calls: |
1204 | either of the following three request calls: |
1139 | |
1205 | |
1140 | aio_lstat "/etc" , sub { ... # pathname as normal string |
1206 | aio_lstat "/etc" , sub { ... # pathname as normal string |
… | |
… | |
1157 | There are some caveats: when directories get renamed (or deleted), the |
1223 | There are some caveats: when directories get renamed (or deleted), the |
1158 | pathname string doesn't change, so will point to the new directory (or |
1224 | pathname string doesn't change, so will point to the new directory (or |
1159 | nowhere at all), while the directory fd, if available on the system, |
1225 | nowhere at all), while the directory fd, if available on the system, |
1160 | will still point to the original directory. Most functions accepting a |
1226 | will still point to the original directory. Most functions accepting a |
1161 | pathname will use the directory fd on newer systems, and the string on |
1227 | pathname will use the directory fd on newer systems, and the string on |
1162 | older systems. Some functions (such as realpath) will always rely on the |
1228 | older systems. Some functions (such as "aio_realpath") will always rely |
1163 | string form of the pathname. |
1229 | on the string form of the pathname. |
1164 | |
1230 | |
1165 | So this functionality is mainly useful to get some protection against |
1231 | So this functionality is mainly useful to get some protection against |
1166 | "chdir", to easily get an absolute path out of a relative path for |
1232 | "chdir", to easily get an absolute path out of a relative path for |
1167 | future reference, and to speed up doing many operations in the same |
1233 | future reference, and to speed up doing many operations in the same |
1168 | directory (e.g. when stat'ing all files in a directory). |
1234 | directory (e.g. when stat'ing all files in a directory). |
… | |
… | |
1181 | fails the request with "ENOENT", there is often no need for error |
1247 | fails the request with "ENOENT", there is often no need for error |
1182 | checking in the "aio_wd" callback, as future requests using the |
1248 | checking in the "aio_wd" callback, as future requests using the |
1183 | value will fail in the expected way. |
1249 | value will fail in the expected way. |
1184 | |
1250 | |
1185 | IO::AIO::CWD |
1251 | IO::AIO::CWD |
1186 | This is a compiletime constant (object) that represents the process |
1252 | This is a compile time constant (object) that represents the process |
1187 | current working directory. |
1253 | current working directory. |
1188 | |
1254 | |
1189 | Specifying this object as working directory object for a pathname is |
1255 | Specifying this object as working directory object for a pathname is |
1190 | as if the pathname would be specified directly, without a directory |
1256 | as if the pathname would be specified directly, without a directory |
1191 | object. For example, these calls are functionally identical: |
1257 | object. For example, these calls are functionally identical: |
… | |
… | |
1416 | Strictly equivalent to: |
1482 | Strictly equivalent to: |
1417 | |
1483 | |
1418 | IO::AIO::poll_wait, IO::AIO::poll_cb |
1484 | IO::AIO::poll_wait, IO::AIO::poll_cb |
1419 | while IO::AIO::nreqs; |
1485 | while IO::AIO::nreqs; |
1420 | |
1486 | |
|
|
1487 | This function can be useful at program aborts, to make sure |
|
|
1488 | outstanding I/O has been done ("IO::AIO" uses an "END" block which |
|
|
1489 | already calls this function on normal exits), or when you are merely |
|
|
1490 | using "IO::AIO" for its more advanced functions, rather than for |
|
|
1491 | async I/O, e.g.: |
|
|
1492 | |
|
|
1493 | my ($dirs, $nondirs); |
|
|
1494 | IO::AIO::aio_scandir "/tmp", 0, sub { ($dirs, $nondirs) = @_ }; |
|
|
1495 | IO::AIO::flush; |
|
|
1496 | # $dirs, $nondirs are now set |
|
|
1497 | |
1421 | IO::AIO::max_poll_reqs $nreqs |
1498 | IO::AIO::max_poll_reqs $nreqs |
1422 | IO::AIO::max_poll_time $seconds |
1499 | IO::AIO::max_poll_time $seconds |
1423 | These set the maximum number of requests (default 0, meaning |
1500 | These set the maximum number of requests (default 0, meaning |
1424 | infinity) that are being processed by "IO::AIO::poll_cb" in one |
1501 | infinity) that are being processed by "IO::AIO::poll_cb" in one |
1425 | call, respectively the maximum amount of time (default 0, meaning |
1502 | call, respectively the maximum amount of time (default 0, meaning |
… | |
… | |
1518 | |
1595 | |
1519 | This is a very bad function to use in interactive programs because |
1596 | This is a very bad function to use in interactive programs because |
1520 | it blocks, and a bad way to reduce concurrency because it is |
1597 | it blocks, and a bad way to reduce concurrency because it is |
1521 | inexact: Better use an "aio_group" together with a feed callback. |
1598 | inexact: Better use an "aio_group" together with a feed callback. |
1522 | |
1599 | |
1523 | It's main use is in scripts without an event loop - when you want to |
1600 | Its main use is in scripts without an event loop - when you want to |
1524 | stat a lot of files, you can write somehting like this: |
1601 | stat a lot of files, you can write something like this: |
1525 | |
1602 | |
1526 | IO::AIO::max_outstanding 32; |
1603 | IO::AIO::max_outstanding 32; |
1527 | |
1604 | |
1528 | for my $path (...) { |
1605 | for my $path (...) { |
1529 | aio_stat $path , ...; |
1606 | aio_stat $path , ...; |
… | |
… | |
1558 | |
1635 | |
1559 | IO::AIO::npending |
1636 | IO::AIO::npending |
1560 | Returns the number of requests currently in the pending state |
1637 | Returns the number of requests currently in the pending state |
1561 | (executed, but not yet processed by poll_cb). |
1638 | (executed, but not yet processed by poll_cb). |
1562 | |
1639 | |
|
|
1640 | SUBSECOND STAT TIME ACCESS |
|
|
1641 | Both "aio_stat"/"aio_lstat" and perl's "stat"/"lstat" functions can |
|
|
1642 | generally find access/modification and change times with subsecond time |
|
|
1643 | accuracy of the system supports it, but perl's built-in functions only |
|
|
1644 | return the integer part. |
|
|
1645 | |
|
|
1646 | The following functions return the timestamps of the most recent stat |
|
|
1647 | with subsecond precision on most systems and work both after |
|
|
1648 | "aio_stat"/"aio_lstat" and perl's "stat"/"lstat" calls. Their return |
|
|
1649 | value is only meaningful after a successful "stat"/"lstat" call, or |
|
|
1650 | during/after a successful "aio_stat"/"aio_lstat" callback. |
|
|
1651 | |
|
|
1652 | This is similar to the Time::HiRes "stat" functions, but can return full |
|
|
1653 | resolution without rounding and work with standard perl "stat", |
|
|
1654 | alleviating the need to call the special "Time::HiRes" functions, which |
|
|
1655 | do not act like their perl counterparts. |
|
|
1656 | |
|
|
1657 | On operating systems or file systems where subsecond time resolution is |
|
|
1658 | not supported or could not be detected, a fractional part of 0 is |
|
|
1659 | returned, so it is always safe to call these functions. |
|
|
1660 | |
|
|
1661 | $seconds = IO::AIO::st_atime, IO::AIO::st_mtime, IO::AIO::st_ctime, |
|
|
1662 | IO::AIO::st_btime |
|
|
1663 | Return the access, modication, change or birth time, respectively, |
|
|
1664 | including fractional part. Due to the limited precision of floating |
|
|
1665 | point, the accuracy on most platforms is only a bit better than |
|
|
1666 | milliseconds for times around now - see the *nsec* function family, |
|
|
1667 | below, for full accuracy. |
|
|
1668 | |
|
|
1669 | File birth time is only available when the OS and perl support it |
|
|
1670 | (on FreeBSD and NetBSD at the time of this writing, although support |
|
|
1671 | is adaptive, so if your OS/perl gains support, IO::AIO can take |
|
|
1672 | advantage of it). On systems where it isn't available, 0 is |
|
|
1673 | currently returned, but this might change to "undef" in a future |
|
|
1674 | version. |
|
|
1675 | |
|
|
1676 | ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtime |
|
|
1677 | Returns access, modification, change and birth time all in one go, |
|
|
1678 | and maybe more times in the future version. |
|
|
1679 | |
|
|
1680 | $nanoseconds = IO::AIO::st_atimensec, IO::AIO::st_mtimensec, |
|
|
1681 | IO::AIO::st_ctimensec, IO::AIO::st_btimensec |
|
|
1682 | Return the fractional access, modifcation, change or birth time, in |
|
|
1683 | nanoseconds, as an integer in the range 0 to 999999999. |
|
|
1684 | |
|
|
1685 | Note that no accessors are provided for access, modification and |
|
|
1686 | change times - you need to get those from "stat _" if required ("int |
|
|
1687 | IO::AIO::st_atime" and so on will *not* generally give you the |
|
|
1688 | correct value). |
|
|
1689 | |
|
|
1690 | $seconds = IO::AIO::st_btimesec |
|
|
1691 | The (integral) seconds part of the file birth time, if available. |
|
|
1692 | |
|
|
1693 | ($atime, $mtime, $ctime, $btime, ...) = IO::AIO::st_xtimensec |
|
|
1694 | Like the functions above, but returns all four times in one go (and |
|
|
1695 | maybe more in future versions). |
|
|
1696 | |
|
|
1697 | $counter = IO::AIO::st_gen |
|
|
1698 | Returns the generation counter (in practice this is just a random |
|
|
1699 | number) of the file. This is only available on platforms which have |
|
|
1700 | this member in their "struct stat" (most BSDs at the time of this |
|
|
1701 | writing) and generally only to the root usert. If unsupported, 0 is |
|
|
1702 | returned, but this might change to "undef" in a future version. |
|
|
1703 | |
|
|
1704 | Example: print the high resolution modification time of /etc, using |
|
|
1705 | "stat", and "IO::AIO::aio_stat". |
|
|
1706 | |
|
|
1707 | if (stat "/etc") { |
|
|
1708 | printf "stat(/etc) mtime: %f\n", IO::AIO::st_mtime; |
|
|
1709 | } |
|
|
1710 | |
|
|
1711 | IO::AIO::aio_stat "/etc", sub { |
|
|
1712 | $_[0] |
|
|
1713 | and return; |
|
|
1714 | |
|
|
1715 | printf "aio_stat(/etc) mtime: %d.%09d\n", (stat _)[9], IO::AIO::st_mtimensec; |
|
|
1716 | }; |
|
|
1717 | |
|
|
1718 | IO::AIO::flush; |
|
|
1719 | |
|
|
1720 | Output of the awbove on my system, showing reduced and full accuracy: |
|
|
1721 | |
|
|
1722 | stat(/etc) mtime: 1534043702.020808 |
|
|
1723 | aio_stat(/etc) mtime: 1534043702.020807792 |
|
|
1724 | |
1563 | MISCELLANEOUS FUNCTIONS |
1725 | MISCELLANEOUS FUNCTIONS |
1564 | IO::AIO implements some functions that might be useful, but are not |
1726 | IO::AIO implements some functions that are useful when you want to use |
1565 | asynchronous. |
1727 | some "Advanced I/O" function not available to in Perl, without going the |
|
|
1728 | "Asynchronous I/O" route. Many of these have an asynchronous "aio_*" |
|
|
1729 | counterpart. |
|
|
1730 | |
|
|
1731 | $numfd = IO::AIO::get_fdlimit |
|
|
1732 | Tries to find the current file descriptor limit and returns it, or |
|
|
1733 | "undef" and sets $! in case of an error. The limit is one larger |
|
|
1734 | than the highest valid file descriptor number. |
|
|
1735 | |
|
|
1736 | IO::AIO::min_fdlimit [$numfd] |
|
|
1737 | Try to increase the current file descriptor limit(s) to at least |
|
|
1738 | $numfd by changing the soft or hard file descriptor resource limit. |
|
|
1739 | If $numfd is missing, it will try to set a very high limit, although |
|
|
1740 | this is not recommended when you know the actual minimum that you |
|
|
1741 | require. |
|
|
1742 | |
|
|
1743 | If the limit cannot be raised enough, the function makes a |
|
|
1744 | best-effort attempt to increase the limit as much as possible, using |
|
|
1745 | various tricks, while still failing. You can query the resulting |
|
|
1746 | limit using "IO::AIO::get_fdlimit". |
|
|
1747 | |
|
|
1748 | If an error occurs, returns "undef" and sets $!, otherwise returns |
|
|
1749 | true. |
1566 | |
1750 | |
1567 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
1751 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
1568 | Calls the "eio_sendfile_sync" function, which is like |
1752 | Calls the "eio_sendfile_sync" function, which is like |
1569 | "aio_sendfile", but is blocking (this makes most sense if you know |
1753 | "aio_sendfile", but is blocking (this makes most sense if you know |
1570 | the input data is likely cached already and the output filehandle is |
1754 | the input data is likely cached already and the output filehandle is |
… | |
… | |
1587 | details). The following advice constants are available: |
1771 | details). The following advice constants are available: |
1588 | "IO::AIO::MADV_NORMAL", "IO::AIO::MADV_SEQUENTIAL", |
1772 | "IO::AIO::MADV_NORMAL", "IO::AIO::MADV_SEQUENTIAL", |
1589 | "IO::AIO::MADV_RANDOM", "IO::AIO::MADV_WILLNEED", |
1773 | "IO::AIO::MADV_RANDOM", "IO::AIO::MADV_WILLNEED", |
1590 | "IO::AIO::MADV_DONTNEED". |
1774 | "IO::AIO::MADV_DONTNEED". |
1591 | |
1775 | |
|
|
1776 | If $offset is negative, counts from the end. If $length is negative, |
|
|
1777 | the remaining length of the $scalar is used. If possible, $length |
|
|
1778 | will be reduced to fit into the $scalar. |
|
|
1779 | |
1592 | On systems that do not implement "posix_madvise", this function |
1780 | On systems that do not implement "posix_madvise", this function |
1593 | returns ENOSYS, otherwise the return value of "posix_madvise". |
1781 | returns ENOSYS, otherwise the return value of "posix_madvise". |
1594 | |
1782 | |
1595 | IO::AIO::mprotect $scalar, $offset, $len, $protect |
1783 | IO::AIO::mprotect $scalar, $offset, $len, $protect |
1596 | Simply calls the "mprotect" function on the preferably AIO::mmap'ed |
1784 | Simply calls the "mprotect" function on the preferably AIO::mmap'ed |
1597 | $scalar (see its manpage for details). The following protect |
1785 | $scalar (see its manpage for details). The following protect |
1598 | constants are available: "IO::AIO::PROT_NONE", "IO::AIO::PROT_READ", |
1786 | constants are available: "IO::AIO::PROT_NONE", "IO::AIO::PROT_READ", |
1599 | "IO::AIO::PROT_WRITE", "IO::AIO::PROT_EXEC". |
1787 | "IO::AIO::PROT_WRITE", "IO::AIO::PROT_EXEC". |
1600 | |
1788 | |
|
|
1789 | If $offset is negative, counts from the end. If $length is negative, |
|
|
1790 | the remaining length of the $scalar is used. If possible, $length |
|
|
1791 | will be reduced to fit into the $scalar. |
|
|
1792 | |
1601 | On systems that do not implement "mprotect", this function returns |
1793 | On systems that do not implement "mprotect", this function returns |
1602 | ENOSYS, otherwise the return value of "mprotect". |
1794 | ENOSYS, otherwise the return value of "mprotect". |
1603 | |
1795 | |
1604 | IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
1796 | IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
1605 | Memory-maps a file (or anonymous memory range) and attaches it to |
1797 | Memory-maps a file (or anonymous memory range) and attaches it to |
1606 | the given $scalar, which will act like a string scalar. Returns true |
1798 | the given $scalar, which will act like a string scalar. Returns true |
1607 | on success, and false otherwise. |
1799 | on success, and false otherwise. |
1608 | |
1800 | |
|
|
1801 | The scalar must exist, but its contents do not matter - this means |
|
|
1802 | you cannot use a nonexistant array or hash element. When in doubt, |
|
|
1803 | "undef" the scalar first. |
|
|
1804 | |
1609 | The only operations allowed on the scalar are "substr"/"vec" that |
1805 | The only operations allowed on the mmapped scalar are |
1610 | don't change the string length, and most read-only operations such |
1806 | "substr"/"vec", which don't change the string length, and most |
1611 | as copying it or searching it with regexes and so on. |
1807 | read-only operations such as copying it or searching it with regexes |
|
|
1808 | and so on. |
1612 | |
1809 | |
1613 | Anything else is unsafe and will, at best, result in memory leaks. |
1810 | Anything else is unsafe and will, at best, result in memory leaks. |
1614 | |
1811 | |
1615 | The memory map associated with the $scalar is automatically removed |
1812 | The memory map associated with the $scalar is automatically removed |
1616 | when the $scalar is destroyed, or when the "IO::AIO::mmap" or |
1813 | when the $scalar is undef'd or destroyed, or when the |
1617 | "IO::AIO::munmap" functions are called. |
1814 | "IO::AIO::mmap" or "IO::AIO::munmap" functions are called on it. |
1618 | |
1815 | |
1619 | This calls the "mmap"(2) function internally. See your system's |
1816 | This calls the "mmap"(2) function internally. See your system's |
1620 | manual page for details on the $length, $prot and $flags parameters. |
1817 | manual page for details on the $length, $prot and $flags parameters. |
1621 | |
1818 | |
1622 | The $length must be larger than zero and smaller than the actual |
1819 | The $length must be larger than zero and smaller than the actual |
… | |
… | |
1626 | "IO::AIO::PROT_EXEC", "IO::AIO::PROT_READ" and/or |
1823 | "IO::AIO::PROT_EXEC", "IO::AIO::PROT_READ" and/or |
1627 | "IO::AIO::PROT_WRITE", |
1824 | "IO::AIO::PROT_WRITE", |
1628 | |
1825 | |
1629 | $flags can be a combination of "IO::AIO::MAP_SHARED" or |
1826 | $flags can be a combination of "IO::AIO::MAP_SHARED" or |
1630 | "IO::AIO::MAP_PRIVATE", or a number of system-specific flags (when |
1827 | "IO::AIO::MAP_PRIVATE", or a number of system-specific flags (when |
1631 | not available, the are defined as 0): "IO::AIO::MAP_ANONYMOUS" |
1828 | not available, the are 0): "IO::AIO::MAP_ANONYMOUS" (which is set to |
1632 | (which is set to "MAP_ANON" if your system only provides this |
1829 | "MAP_ANON" if your system only provides this constant), |
|
|
1830 | "IO::AIO::MAP_LOCKED", "IO::AIO::MAP_NORESERVE", |
1633 | constant), "IO::AIO::MAP_HUGETLB", "IO::AIO::MAP_LOCKED", |
1831 | "IO::AIO::MAP_POPULATE", "IO::AIO::MAP_NONBLOCK", |
|
|
1832 | "IO::AIO::MAP_FIXED", "IO::AIO::MAP_GROWSDOWN", |
1634 | "IO::AIO::MAP_NORESERVE", "IO::AIO::MAP_POPULATE" or |
1833 | "IO::AIO::MAP_32BIT", "IO::AIO::MAP_HUGETLB" or |
1635 | "IO::AIO::MAP_NONBLOCK" |
1834 | "IO::AIO::MAP_STACK". |
1636 | |
1835 | |
1637 | If $fh is "undef", then a file descriptor of -1 is passed. |
1836 | If $fh is "undef", then a file descriptor of -1 is passed. |
1638 | |
1837 | |
1639 | $offset is the offset from the start of the file - it generally must |
1838 | $offset is the offset from the start of the file - it generally must |
1640 | be a multiple of "IO::AIO::PAGESIZE" and defaults to 0. |
1839 | be a multiple of "IO::AIO::PAGESIZE" and defaults to 0. |
… | |
… | |
1652 | |
1851 | |
1653 | my $fast_md5 = md5 $data; |
1852 | my $fast_md5 = md5 $data; |
1654 | |
1853 | |
1655 | IO::AIO::munmap $scalar |
1854 | IO::AIO::munmap $scalar |
1656 | Removes a previous mmap and undefines the $scalar. |
1855 | Removes a previous mmap and undefines the $scalar. |
|
|
1856 | |
|
|
1857 | IO::AIO::mremap $scalar, $new_length, $flags = MREMAP_MAYMOVE[, |
|
|
1858 | $new_address = 0] |
|
|
1859 | Calls the Linux-specific mremap(2) system call. The $scalar must |
|
|
1860 | have been mapped by "IO::AIO::mmap", and $flags must currently |
|
|
1861 | either be 0 or "IO::AIO::MREMAP_MAYMOVE". |
|
|
1862 | |
|
|
1863 | Returns true if successful, and false otherwise. If the underlying |
|
|
1864 | mmapped region has changed address, then the true value has the |
|
|
1865 | numerical value 1, otherwise it has the numerical value 0: |
|
|
1866 | |
|
|
1867 | my $success = IO::AIO::mremap $mmapped, 8192, IO::AIO::MREMAP_MAYMOVE |
|
|
1868 | or die "mremap: $!"; |
|
|
1869 | |
|
|
1870 | if ($success*1) { |
|
|
1871 | warn "scalar has chanegd address in memory\n"; |
|
|
1872 | } |
|
|
1873 | |
|
|
1874 | "IO::AIO::MREMAP_FIXED" and the $new_address argument are currently |
|
|
1875 | implemented, but not supported and might go away in a future |
|
|
1876 | version. |
|
|
1877 | |
|
|
1878 | On systems where this call is not supported or is not emulated, this |
|
|
1879 | call returns falls and sets $! to "ENOSYS". |
|
|
1880 | |
|
|
1881 | IO::AIO::mlockall $flags |
|
|
1882 | Calls the "eio_mlockall_sync" function, which is like |
|
|
1883 | "aio_mlockall", but is blocking. |
1657 | |
1884 | |
1658 | IO::AIO::munlock $scalar, $offset = 0, $length = undef |
1885 | IO::AIO::munlock $scalar, $offset = 0, $length = undef |
1659 | Calls the "munlock" function, undoing the effects of a previous |
1886 | Calls the "munlock" function, undoing the effects of a previous |
1660 | "aio_mlock" call (see its description for details). |
1887 | "aio_mlock" call (see its description for details). |
1661 | |
1888 | |
1662 | IO::AIO::munlockall |
1889 | IO::AIO::munlockall |
1663 | Calls the "munlockall" function. |
1890 | Calls the "munlockall" function. |
1664 | |
1891 | |
1665 | On systems that do not implement "munlockall", this function returns |
1892 | On systems that do not implement "munlockall", this function returns |
1666 | ENOSYS, otherwise the return value of "munlockall". |
1893 | ENOSYS, otherwise the return value of "munlockall". |
|
|
1894 | |
|
|
1895 | $fh = IO::AIO::accept4 $r_fh, $sockaddr, $sockaddr_maxlen, $flags |
|
|
1896 | Uses the GNU/Linux accept4(2) syscall, if available, to accept a |
|
|
1897 | socket and return the new file handle on success, or sets $! and |
|
|
1898 | returns "undef" on error. |
|
|
1899 | |
|
|
1900 | The remote name of the new socket will be stored in $sockaddr, which |
|
|
1901 | will be extended to allow for at least $sockaddr_maxlen octets. If |
|
|
1902 | the socket name does not fit into $sockaddr_maxlen octets, this is |
|
|
1903 | signaled by returning a longer string in $sockaddr, which might or |
|
|
1904 | might not be truncated. |
|
|
1905 | |
|
|
1906 | To accept name-less sockets, use "undef" for $sockaddr and 0 for |
|
|
1907 | $sockaddr_maxlen. |
|
|
1908 | |
|
|
1909 | The main reasons to use this syscall rather than portable accept(2) |
|
|
1910 | are that you can specify "SOCK_NONBLOCK" and/or "SOCK_CLOEXEC" flags |
|
|
1911 | and you can accept name-less sockets by specifying 0 for |
|
|
1912 | $sockaddr_maxlen, which is sadly not possible with perl's interface |
|
|
1913 | to "accept". |
1667 | |
1914 | |
1668 | IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags |
1915 | IO::AIO::splice $r_fh, $r_off, $w_fh, $w_off, $length, $flags |
1669 | Calls the GNU/Linux splice(2) syscall, if available. If $r_off or |
1916 | Calls the GNU/Linux splice(2) syscall, if available. If $r_off or |
1670 | $w_off are "undef", then "NULL" is passed for these, otherwise they |
1917 | $w_off are "undef", then "NULL" is passed for these, otherwise they |
1671 | should be the file offset. |
1918 | should be the file offset. |
… | |
… | |
1678 | "IO::AIO::SPLICE_F_MORE" and "IO::AIO::SPLICE_F_GIFT". |
1925 | "IO::AIO::SPLICE_F_MORE" and "IO::AIO::SPLICE_F_GIFT". |
1679 | |
1926 | |
1680 | See the splice(2) manpage for details. |
1927 | See the splice(2) manpage for details. |
1681 | |
1928 | |
1682 | IO::AIO::tee $r_fh, $w_fh, $length, $flags |
1929 | IO::AIO::tee $r_fh, $w_fh, $length, $flags |
1683 | Calls the GNU/Linux tee(2) syscall, see it's manpage and the |
1930 | Calls the GNU/Linux tee(2) syscall, see its manpage and the |
1684 | description for "IO::AIO::splice" above for details. |
1931 | description for "IO::AIO::splice" above for details. |
1685 | |
1932 | |
1686 | $actual_size = IO::AIO::pipesize $r_fh[, $new_size] |
1933 | $actual_size = IO::AIO::pipesize $r_fh[, $new_size] |
1687 | Attempts to query or change the pipe buffer size. Obviously works |
1934 | Attempts to query or change the pipe buffer size. Obviously works |
1688 | only on pipes, and currently works only on GNU/Linux systems, and |
1935 | only on pipes, and currently works only on GNU/Linux systems, and |
1689 | fails with -1/"ENOSYS" everywhere else. If anybody knows how to |
1936 | fails with -1/"ENOSYS" everywhere else. If anybody knows how to |
1690 | influence pipe buffer size on other systems, drop me a note. |
1937 | influence pipe buffer size on other systems, drop me a note. |
|
|
1938 | |
|
|
1939 | ($rfh, $wfh) = IO::AIO::pipe2 [$flags] |
|
|
1940 | This is a direct interface to the Linux pipe2(2) system call. If |
|
|
1941 | $flags is missing or 0, then this should be the same as a call to |
|
|
1942 | perl's built-in "pipe" function and create a new pipe, and works on |
|
|
1943 | systems that lack the pipe2 syscall. On win32, this case invokes |
|
|
1944 | "_pipe (..., 4096, O_BINARY)". |
|
|
1945 | |
|
|
1946 | If $flags is non-zero, it tries to invoke the pipe2 system call with |
|
|
1947 | the given flags (Linux 2.6.27, glibc 2.9). |
|
|
1948 | |
|
|
1949 | On success, the read and write file handles are returned. |
|
|
1950 | |
|
|
1951 | On error, nothing will be returned. If the pipe2 syscall is missing |
|
|
1952 | and $flags is non-zero, fails with "ENOSYS". |
|
|
1953 | |
|
|
1954 | Please refer to pipe2(2) for more info on the $flags, but at the |
|
|
1955 | time of this writing, "IO::AIO::O_CLOEXEC", "IO::AIO::O_NONBLOCK" |
|
|
1956 | and "IO::AIO::O_DIRECT" (Linux 3.4, for packet-based pipes) were |
|
|
1957 | supported. |
|
|
1958 | |
|
|
1959 | Example: create a pipe race-free w.r.t. threads and fork: |
|
|
1960 | |
|
|
1961 | my ($rfh, $wfh) = IO::AIO::pipe2 IO::AIO::O_CLOEXEC |
|
|
1962 | or die "pipe2: $!\n"; |
|
|
1963 | |
|
|
1964 | $fh = IO::AIO::memfd_create $pathname[, $flags] |
|
|
1965 | This is a direct interface to the Linux memfd_create(2) system call. |
|
|
1966 | The (unhelpful) default for $flags is 0, but your default should be |
|
|
1967 | "IO::AIO::MFD_CLOEXEC". |
|
|
1968 | |
|
|
1969 | On success, the new memfd filehandle is returned, otherwise returns |
|
|
1970 | "undef". If the memfd_create syscall is missing, fails with |
|
|
1971 | "ENOSYS". |
|
|
1972 | |
|
|
1973 | Please refer to memfd_create(2) for more info on this call. |
|
|
1974 | |
|
|
1975 | The following $flags values are available: "IO::AIO::MFD_CLOEXEC", |
|
|
1976 | "IO::AIO::MFD_ALLOW_SEALING" and "IO::AIO::MFD_HUGETLB". |
|
|
1977 | |
|
|
1978 | Example: create a new memfd. |
|
|
1979 | |
|
|
1980 | my $fh = IO::AIO::memfd_create "somenameforprocfd", IO::AIO::MFD_CLOEXEC |
|
|
1981 | or die "memfd_create: $!\n"; |
|
|
1982 | |
|
|
1983 | $fh = IO::AIO::pidfd_open $pid[, $flags] |
|
|
1984 | This is an interface to the Linux pidfd_open(2) system call. The |
|
|
1985 | default for $flags is 0. |
|
|
1986 | |
|
|
1987 | On success, a new pidfd filehandle is returned (that is already set |
|
|
1988 | to close-on-exec), otherwise returns "undef". If the syscall is |
|
|
1989 | missing, fails with "ENOSYS". |
|
|
1990 | |
|
|
1991 | Example: open pid 6341 as pidfd. |
|
|
1992 | |
|
|
1993 | my $fh = IO::AIO::pidfd_open 6341 |
|
|
1994 | or die "pidfd_open: $!\n"; |
|
|
1995 | |
|
|
1996 | $status = IO::AIO::pidfd_send_signal $pidfh, $signal[, $siginfo[, |
|
|
1997 | $flags]] |
|
|
1998 | This is an interface to the Linux pidfd_send_signal system call. The |
|
|
1999 | default for $siginfo is "undef" and the default for $flags is 0. |
|
|
2000 | |
|
|
2001 | Returns the system call status. If the syscall is missing, fails |
|
|
2002 | with "ENOSYS". |
|
|
2003 | |
|
|
2004 | When specified, $siginfo must be a reference to a hash with one or |
|
|
2005 | more of the following members: |
|
|
2006 | |
|
|
2007 | code - the "si_code" member |
|
|
2008 | pid - the "si_pid" member |
|
|
2009 | uid - the "si_uid" member |
|
|
2010 | value_int - the "si_value.sival_int" member |
|
|
2011 | value_ptr - the "si_value.sival_ptr" member, specified as an integer |
|
|
2012 | |
|
|
2013 | Example: send a SIGKILL to the specified process. |
|
|
2014 | |
|
|
2015 | my $status = IO::AIO::pidfd_send_signal $pidfh, 9, undef |
|
|
2016 | and die "pidfd_send_signal: $!\n"; |
|
|
2017 | |
|
|
2018 | Example: send a SIGKILL to the specified process with extra data. |
|
|
2019 | |
|
|
2020 | my $status = IO::AIO::pidfd_send_signal $pidfh, 9, { code => -1, value_int => 7 } |
|
|
2021 | and die "pidfd_send_signal: $!\n"; |
|
|
2022 | |
|
|
2023 | $fh = IO::AIO::pidfd_getfd $pidfh, $targetfd[, $flags] |
|
|
2024 | This is an interface to the Linux pidfd_getfd system call. The |
|
|
2025 | default for $flags is 0. |
|
|
2026 | |
|
|
2027 | On success, returns a dup'ed copy of the target file descriptor |
|
|
2028 | (specified as an integer) returned (that is already set to |
|
|
2029 | close-on-exec), otherwise returns "undef". If the syscall is |
|
|
2030 | missing, fails with "ENOSYS". |
|
|
2031 | |
|
|
2032 | Example: get a copy of standard error of another process and print |
|
|
2033 | soemthing to it. |
|
|
2034 | |
|
|
2035 | my $errfh = IO::AIO::pidfd_getfd $pidfh, 2 |
|
|
2036 | or die "pidfd_getfd: $!\n"; |
|
|
2037 | print $errfh "stderr\n"; |
|
|
2038 | |
|
|
2039 | $fh = IO::AIO::eventfd [$initval, [$flags]] |
|
|
2040 | This is a direct interface to the Linux eventfd(2) system call. The |
|
|
2041 | (unhelpful) defaults for $initval and $flags are 0 for both. |
|
|
2042 | |
|
|
2043 | On success, the new eventfd filehandle is returned, otherwise |
|
|
2044 | returns "undef". If the eventfd syscall is missing, fails with |
|
|
2045 | "ENOSYS". |
|
|
2046 | |
|
|
2047 | Please refer to eventfd(2) for more info on this call. |
|
|
2048 | |
|
|
2049 | The following symbol flag values are available: |
|
|
2050 | "IO::AIO::EFD_CLOEXEC", "IO::AIO::EFD_NONBLOCK" and |
|
|
2051 | "IO::AIO::EFD_SEMAPHORE" (Linux 2.6.30). |
|
|
2052 | |
|
|
2053 | Example: create a new eventfd filehandle: |
|
|
2054 | |
|
|
2055 | $fh = IO::AIO::eventfd 0, IO::AIO::EFD_CLOEXEC |
|
|
2056 | or die "eventfd: $!\n"; |
|
|
2057 | |
|
|
2058 | $fh = IO::AIO::timerfd_create $clockid[, $flags] |
|
|
2059 | This is a direct interface to the Linux timerfd_create(2) system |
|
|
2060 | call. The (unhelpful) default for $flags is 0, but your default |
|
|
2061 | should be "IO::AIO::TFD_CLOEXEC". |
|
|
2062 | |
|
|
2063 | On success, the new timerfd filehandle is returned, otherwise |
|
|
2064 | returns "undef". If the timerfd_create syscall is missing, fails |
|
|
2065 | with "ENOSYS". |
|
|
2066 | |
|
|
2067 | Please refer to timerfd_create(2) for more info on this call. |
|
|
2068 | |
|
|
2069 | The following $clockid values are available: |
|
|
2070 | "IO::AIO::CLOCK_REALTIME", "IO::AIO::CLOCK_MONOTONIC" |
|
|
2071 | "IO::AIO::CLOCK_CLOCK_BOOTTIME" (Linux 3.15) |
|
|
2072 | "IO::AIO::CLOCK_CLOCK_REALTIME_ALARM" (Linux 3.11) and |
|
|
2073 | "IO::AIO::CLOCK_CLOCK_BOOTTIME_ALARM" (Linux 3.11). |
|
|
2074 | |
|
|
2075 | The following $flags values are available (Linux 2.6.27): |
|
|
2076 | "IO::AIO::TFD_NONBLOCK" and "IO::AIO::TFD_CLOEXEC". |
|
|
2077 | |
|
|
2078 | Example: create a new timerfd and set it to one-second repeated |
|
|
2079 | alarms, then wait for two alarms: |
|
|
2080 | |
|
|
2081 | my $fh = IO::AIO::timerfd_create IO::AIO::CLOCK_BOOTTIME, IO::AIO::TFD_CLOEXEC |
|
|
2082 | or die "timerfd_create: $!\n"; |
|
|
2083 | |
|
|
2084 | defined IO::AIO::timerfd_settime $fh, 0, 1, 1 |
|
|
2085 | or die "timerfd_settime: $!\n"; |
|
|
2086 | |
|
|
2087 | for (1..2) { |
|
|
2088 | 8 == sysread $fh, my $buf, 8 |
|
|
2089 | or die "timerfd read failure\n"; |
|
|
2090 | |
|
|
2091 | printf "number of expirations (likely 1): %d\n", |
|
|
2092 | unpack "Q", $buf; |
|
|
2093 | } |
|
|
2094 | |
|
|
2095 | ($cur_interval, $cur_value) = IO::AIO::timerfd_settime $fh, $flags, |
|
|
2096 | $new_interval, $nbw_value |
|
|
2097 | This is a direct interface to the Linux timerfd_settime(2) system |
|
|
2098 | call. Please refer to its manpage for more info on this call. |
|
|
2099 | |
|
|
2100 | The new itimerspec is specified using two (possibly fractional) |
|
|
2101 | second values, $new_interval and $new_value). |
|
|
2102 | |
|
|
2103 | On success, the current interval and value are returned (as per |
|
|
2104 | "timerfd_gettime"). On failure, the empty list is returned. |
|
|
2105 | |
|
|
2106 | The following $flags values are available: |
|
|
2107 | "IO::AIO::TFD_TIMER_ABSTIME" and "IO::AIO::TFD_TIMER_CANCEL_ON_SET". |
|
|
2108 | |
|
|
2109 | See "IO::AIO::timerfd_create" for a full example. |
|
|
2110 | |
|
|
2111 | ($cur_interval, $cur_value) = IO::AIO::timerfd_gettime $fh |
|
|
2112 | This is a direct interface to the Linux timerfd_gettime(2) system |
|
|
2113 | call. Please refer to its manpage for more info on this call. |
|
|
2114 | |
|
|
2115 | On success, returns the current values of interval and value for the |
|
|
2116 | given timerfd (as potentially fractional second values). On failure, |
|
|
2117 | the empty list is returned. |
1691 | |
2118 | |
1692 | EVENT LOOP INTEGRATION |
2119 | EVENT LOOP INTEGRATION |
1693 | It is recommended to use AnyEvent::AIO to integrate IO::AIO |
2120 | It is recommended to use AnyEvent::AIO to integrate IO::AIO |
1694 | automatically into many event loops: |
2121 | automatically into many event loops: |
1695 | |
2122 | |
… | |
… | |
1745 | forking, if "IO::AIO" was used in the parent. Calling it while |
2172 | forking, if "IO::AIO" was used in the parent. Calling it while |
1746 | IO::AIO is active in the process will result in undefined behaviour. |
2173 | IO::AIO is active in the process will result in undefined behaviour. |
1747 | Calling it at any time will also result in any undefined (by POSIX) |
2174 | Calling it at any time will also result in any undefined (by POSIX) |
1748 | behaviour. |
2175 | behaviour. |
1749 | |
2176 | |
|
|
2177 | LINUX-SPECIFIC CALLS |
|
|
2178 | When a call is documented as "linux-specific" then this means it |
|
|
2179 | originated on GNU/Linux. "IO::AIO" will usually try to autodetect the |
|
|
2180 | availability and compatibility of such calls regardless of the platform |
|
|
2181 | it is compiled on, so platforms such as FreeBSD which often implement |
|
|
2182 | these calls will work. When in doubt, call them and see if they fail wth |
|
|
2183 | "ENOSYS". |
|
|
2184 | |
1750 | MEMORY USAGE |
2185 | MEMORY USAGE |
1751 | Per-request usage: |
2186 | Per-request usage: |
1752 | |
2187 | |
1753 | Each aio request uses - depending on your architecture - around 100-200 |
2188 | Each aio request uses - depending on your architecture - around 100-200 |
1754 | bytes of memory. In addition, stat requests need a stat buffer (possibly |
2189 | bytes of memory. In addition, stat requests need a stat buffer (possibly |
… | |
… | |
1764 | In the execution phase, some aio requests require more memory for |
2199 | In the execution phase, some aio requests require more memory for |
1765 | temporary buffers, and each thread requires a stack and other data |
2200 | temporary buffers, and each thread requires a stack and other data |
1766 | structures (usually around 16k-128k, depending on the OS). |
2201 | structures (usually around 16k-128k, depending on the OS). |
1767 | |
2202 | |
1768 | KNOWN BUGS |
2203 | KNOWN BUGS |
1769 | Known bugs will be fixed in the next release. |
2204 | Known bugs will be fixed in the next release :) |
|
|
2205 | |
|
|
2206 | KNOWN ISSUES |
|
|
2207 | Calls that try to "import" foreign memory areas (such as "IO::AIO::mmap" |
|
|
2208 | or "IO::AIO::aio_slurp") do not work with generic lvalues, such as |
|
|
2209 | non-created hash slots or other scalars I didn't think of. It's best to |
|
|
2210 | avoid such and either use scalar variables or making sure that the |
|
|
2211 | scalar exists (e.g. by storing "undef") and isn't "funny" (e.g. tied). |
|
|
2212 | |
|
|
2213 | I am not sure anything can be done about this, so this is considered a |
|
|
2214 | known issue, rather than a bug. |
1770 | |
2215 | |
1771 | SEE ALSO |
2216 | SEE ALSO |
1772 | AnyEvent::AIO for easy integration into event loops, Coro::AIO for a |
2217 | AnyEvent::AIO for easy integration into event loops, Coro::AIO for a |
1773 | more natural syntax. |
2218 | more natural syntax and IO::FDPass for file descriptor passing. |
1774 | |
2219 | |
1775 | AUTHOR |
2220 | AUTHOR |
1776 | Marc Lehmann <schmorp@schmorp.de> |
2221 | Marc Lehmann <schmorp@schmorp.de> |
1777 | http://home.schmorp.de/ |
2222 | http://home.schmorp.de/ |
1778 | |
2223 | |