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 | |
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167 | use common::sense; |
171 | use common::sense; |
168 | |
172 | |
169 | use base 'Exporter'; |
173 | use base 'Exporter'; |
170 | |
174 | |
171 | BEGIN { |
175 | BEGIN { |
172 | our $VERSION = 4.33; |
176 | our $VERSION = 4.35; |
173 | |
177 | |
174 | our @AIO_REQ = qw(aio_sendfile aio_seek aio_read aio_write aio_open aio_close |
178 | our @AIO_REQ = qw(aio_sendfile aio_seek aio_read aio_write aio_open aio_close |
175 | 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 |
176 | aio_scandir aio_symlink aio_readlink aio_realpath aio_sync |
180 | aio_scandir aio_symlink aio_readlink aio_realpath aio_fcntl aio_ioctl |
177 | aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range aio_allocate |
181 | aio_sync aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range |
178 | aio_pathsync aio_readahead aio_fiemap |
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 |
184 | aio_wd); |
188 | aio_wd); |
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229 | aio_link $srcpath, $dstpath, $callback->($status) |
233 | aio_link $srcpath, $dstpath, $callback->($status) |
230 | aio_symlink $srcpath, $dstpath, $callback->($status) |
234 | aio_symlink $srcpath, $dstpath, $callback->($status) |
231 | aio_readlink $pathname, $callback->($link) |
235 | aio_readlink $pathname, $callback->($link) |
232 | aio_realpath $pathname, $callback->($path) |
236 | aio_realpath $pathname, $callback->($path) |
233 | aio_rename $srcpath, $dstpath, $callback->($status) |
237 | aio_rename $srcpath, $dstpath, $callback->($status) |
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238 | aio_rename2 $srcpath, $dstpath, $flags, $callback->($status) |
234 | aio_mkdir $pathname, $mode, $callback->($status) |
239 | aio_mkdir $pathname, $mode, $callback->($status) |
235 | aio_rmdir $pathname, $callback->($status) |
240 | aio_rmdir $pathname, $callback->($status) |
236 | aio_readdir $pathname, $callback->($entries) |
241 | aio_readdir $pathname, $callback->($entries) |
237 | aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
242 | aio_readdirx $pathname, $flags, $callback->($entries, $flags) |
238 | IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST |
243 | IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST |
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240 | aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs) |
245 | aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs) |
241 | aio_load $pathname, $data, $callback->($status) |
246 | aio_load $pathname, $data, $callback->($status) |
242 | aio_copy $srcpath, $dstpath, $callback->($status) |
247 | aio_copy $srcpath, $dstpath, $callback->($status) |
243 | aio_move $srcpath, $dstpath, $callback->($status) |
248 | aio_move $srcpath, $dstpath, $callback->($status) |
244 | aio_rmtree $pathname, $callback->($status) |
249 | aio_rmtree $pathname, $callback->($status) |
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250 | aio_fcntl $fh, $cmd, $arg, $callback->($status) |
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251 | aio_ioctl $fh, $request, $buf, $callback->($status) |
245 | aio_sync $callback->($status) |
252 | aio_sync $callback->($status) |
246 | aio_syncfs $fh, $callback->($status) |
253 | aio_syncfs $fh, $callback->($status) |
247 | aio_fsync $fh, $callback->($status) |
254 | aio_fsync $fh, $callback->($status) |
248 | aio_fdatasync $fh, $callback->($status) |
255 | aio_fdatasync $fh, $callback->($status) |
249 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
256 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
250 | aio_pathsync $pathname, $callback->($status) |
257 | aio_pathsync $pathname, $callback->($status) |
251 | aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
258 | aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status) |
252 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
259 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
253 | aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
260 | aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
254 | aio_mlockall $flags, $callback->($status) |
261 | aio_mlockall $flags, $callback->($status) |
255 | aio_group $callback->(...) |
262 | aio_group $callback->(...) |
256 | aio_nop $callback->() |
263 | aio_nop $callback->() |
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270 | IO::AIO::idle_timeout $seconds |
277 | IO::AIO::idle_timeout $seconds |
271 | IO::AIO::max_outstanding $maxreqs |
278 | IO::AIO::max_outstanding $maxreqs |
272 | IO::AIO::nreqs |
279 | IO::AIO::nreqs |
273 | IO::AIO::nready |
280 | IO::AIO::nready |
274 | IO::AIO::npending |
281 | IO::AIO::npending |
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282 | IO::AIO::min_fdlimit $nfd; |
275 | |
283 | |
276 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
284 | IO::AIO::sendfile $ofh, $ifh, $offset, $count |
277 | IO::AIO::fadvise $fh, $offset, $len, $advice |
285 | IO::AIO::fadvise $fh, $offset, $len, $advice |
278 | IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]] |
286 | IO::AIO::mmap $scalar, $length, $prot, $flags[, $fh[, $offset]] |
279 | IO::AIO::munmap $scalar |
287 | IO::AIO::munmap $scalar |
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439 | =item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
447 | =item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
440 | |
448 | |
441 | =item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
449 | =item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
442 | |
450 | |
443 | Reads or writes C<$length> bytes from or to the specified C<$fh> and |
451 | Reads or writes C<$length> bytes from or to the specified C<$fh> and |
444 | C<$offset> into the scalar given by C<$data> and offset C<$dataoffset> |
452 | C<$offset> into the scalar given by C<$data> and offset C<$dataoffset> and |
445 | and calls the callback without the actual number of bytes read (or -1 on |
453 | calls the callback with the actual number of bytes transferred (or -1 on |
446 | error, just like the syscall). |
454 | error, just like the syscall). |
447 | |
455 | |
448 | C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to |
456 | C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to |
449 | offset plus the actual number of bytes read. |
457 | offset plus the actual number of bytes read. |
450 | |
458 | |
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508 | As native sendfile syscalls (as practically any non-POSIX interface hacked |
516 | As native sendfile syscalls (as practically any non-POSIX interface hacked |
509 | together in a hurry to improve benchmark numbers) tend to be rather buggy |
517 | together in a hurry to improve benchmark numbers) tend to be rather buggy |
510 | on many systems, this implementation tries to work around some known bugs |
518 | on many systems, this implementation tries to work around some known bugs |
511 | in Linux and FreeBSD kernels (probably others, too), but that might fail, |
519 | in Linux and FreeBSD kernels (probably others, too), but that might fail, |
512 | so you really really should check the return value of C<aio_sendfile> - |
520 | so you really really should check the return value of C<aio_sendfile> - |
513 | fewre bytes than expected might have been transferred. |
521 | fewer bytes than expected might have been transferred. |
514 | |
522 | |
515 | |
523 | |
516 | =item aio_readahead $fh,$offset,$length, $callback->($retval) |
524 | =item aio_readahead $fh,$offset,$length, $callback->($retval) |
517 | |
525 | |
518 | C<aio_readahead> populates the page cache with data from a file so that |
526 | C<aio_readahead> populates the page cache with data from a file so that |
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522 | whole pages, so that offset is effectively rounded down to a page boundary |
530 | whole pages, so that offset is effectively rounded down to a page boundary |
523 | and bytes are read up to the next page boundary greater than or equal to |
531 | and bytes are read up to the next page boundary greater than or equal to |
524 | (off-set+length). C<aio_readahead> does not read beyond the end of the |
532 | (off-set+length). C<aio_readahead> does not read beyond the end of the |
525 | file. The current file offset of the file is left unchanged. |
533 | file. The current file offset of the file is left unchanged. |
526 | |
534 | |
527 | If that syscall doesn't exist (likely if your OS isn't Linux) it will be |
535 | If that syscall doesn't exist (likely if your kernel isn't Linux) it will |
528 | emulated by simply reading the data, which would have a similar effect. |
536 | be emulated by simply reading the data, which would have a similar effect. |
529 | |
537 | |
530 | |
538 | |
531 | =item aio_stat $fh_or_path, $callback->($status) |
539 | =item aio_stat $fh_or_path, $callback->($status) |
532 | |
540 | |
533 | =item aio_lstat $fh, $callback->($status) |
541 | =item aio_lstat $fh, $callback->($status) |
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733 | C<$mode> is usually C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> to allocate |
741 | C<$mode> is usually C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> to allocate |
734 | space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE | IO::AIO::FALLOC_FL_KEEP_SIZE>, |
742 | space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE | IO::AIO::FALLOC_FL_KEEP_SIZE>, |
735 | to deallocate a file range. |
743 | to deallocate a file range. |
736 | |
744 | |
737 | IO::AIO also supports C<FALLOC_FL_COLLAPSE_RANGE>, to remove a range |
745 | IO::AIO also supports C<FALLOC_FL_COLLAPSE_RANGE>, to remove a range |
738 | (without leaving a hole) and C<FALLOC_FL_ZERO_RANGE>, to zero a range (see |
746 | (without leaving a hole), C<FALLOC_FL_ZERO_RANGE>, to zero a range, |
739 | your L<fallocate(2)> manpage). |
747 | C<FALLOC_FL_INSERT_RANGE> to insert a range and C<FALLOC_FL_UNSHARE_RANGE> |
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748 | to unshare shared blocks (see your L<fallocate(2)> manpage). |
740 | |
749 | |
741 | The file system block size used by C<fallocate> is presumably the |
750 | The file system block size used by C<fallocate> is presumably the |
742 | C<f_bsize> returned by C<statvfs>. |
751 | C<f_bsize> returned by C<statvfs>, but different filesystems and filetypes |
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752 | can dictate other limitations. |
743 | |
753 | |
744 | If C<fallocate> isn't available or cannot be emulated (currently no |
754 | If C<fallocate> isn't available or cannot be emulated (currently no |
745 | emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>. |
755 | emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>. |
746 | |
756 | |
747 | |
757 | |
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804 | rename(2) and call the callback with the result code. |
814 | rename(2) and call the callback with the result code. |
805 | |
815 | |
806 | On systems that support the AIO::WD working directory abstraction |
816 | On systems that support the AIO::WD working directory abstraction |
807 | natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead |
817 | natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead |
808 | of failing, C<rename> is called on the absolute path of C<$wd>. |
818 | of failing, C<rename> is called on the absolute path of C<$wd>. |
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819 | |
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820 | |
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821 | =item aio_rename2 $srcpath, $dstpath, $flags, $callback->($status) |
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822 | |
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823 | Basically a version of C<aio_rename> with an additional C<$flags> |
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824 | argument. Calling this with C<$flags=0> is the same as calling |
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825 | C<aio_rename>. |
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826 | |
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827 | Non-zero flags are currently only supported on GNU/Linux systems that |
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828 | support renameat2. Other systems fail with C<ENOSYS> in this case. |
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829 | |
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830 | The following constants are available (missing ones are, as usual C<0>), |
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831 | see renameat2(2) for details: |
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832 | |
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833 | C<IO::AIO::RENAME_NOREPLACE>, C<IO::AIO::RENAME_EXCHANGE> |
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834 | and C<IO::AIO::RENAME_WHITEOUT>. |
809 | |
835 | |
810 | |
836 | |
811 | =item aio_mkdir $pathname, $mode, $callback->($status) |
837 | =item aio_mkdir $pathname, $mode, $callback->($status) |
812 | |
838 | |
813 | Asynchronously mkdir (create) a directory and call the callback with |
839 | Asynchronously mkdir (create) a directory and call the callback with |
… | |
… | |
932 | =item aio_copy $srcpath, $dstpath, $callback->($status) |
958 | =item aio_copy $srcpath, $dstpath, $callback->($status) |
933 | |
959 | |
934 | Try to copy the I<file> (directories not supported as either source or |
960 | Try to copy the I<file> (directories not supported as either source or |
935 | destination) from C<$srcpath> to C<$dstpath> and call the callback with |
961 | destination) from C<$srcpath> to C<$dstpath> and call the callback with |
936 | a status of C<0> (ok) or C<-1> (error, see C<$!>). |
962 | a status of C<0> (ok) or C<-1> (error, see C<$!>). |
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963 | |
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964 | Existing destination files will be truncated. |
937 | |
965 | |
938 | This is a composite request that creates the destination file with |
966 | This is a composite request that creates the destination file with |
939 | mode 0200 and copies the contents of the source file into it using |
967 | mode 0200 and copies the contents of the source file into it using |
940 | C<aio_sendfile>, followed by restoring atime, mtime, access mode and |
968 | C<aio_sendfile>, followed by restoring atime, mtime, access mode and |
941 | uid/gid, in that order. |
969 | uid/gid, in that order. |
… | |
… | |
1227 | }; |
1255 | }; |
1228 | |
1256 | |
1229 | $grp |
1257 | $grp |
1230 | } |
1258 | } |
1231 | |
1259 | |
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1260 | =item aio_fcntl $fh, $cmd, $arg, $callback->($status) |
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1261 | |
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1262 | =item aio_ioctl $fh, $request, $buf, $callback->($status) |
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1263 | |
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1264 | These work just like the C<fcntl> and C<ioctl> built-in functions, except |
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1265 | they execute asynchronously and pass the return value to the callback. |
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1266 | |
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1267 | Both calls can be used for a lot of things, some of which make more sense |
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1268 | to run asynchronously in their own thread, while some others make less |
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1269 | sense. For example, calls that block waiting for external events, such |
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1270 | as locking, will also lock down an I/O thread while it is waiting, which |
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1271 | can deadlock the whole I/O system. At the same time, there might be no |
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1272 | alternative to using a thread to wait. |
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1273 | |
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1274 | So in general, you should only use these calls for things that do |
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1275 | (filesystem) I/O, not for things that wait for other events (network, |
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1276 | other processes), although if you are careful and know what you are doing, |
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1277 | you still can. |
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1278 | |
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1279 | The following constants are available (missing ones are, as usual C<0>): |
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1280 | |
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1281 | C<F_DUPFD_CLOEXEC>, |
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1282 | |
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1283 | C<F_OFD_GETLK>, C<F_OFD_SETLK>, C<F_OFD_GETLKW>, |
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1284 | |
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1285 | C<FIFREEZE>, C<FITHAW>, C<FITRIM>, C<FICLONE>, C<FICLONERANGE>, C<FIDEDUPERANGE>. |
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1286 | |
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1287 | C<FS_IOC_GETFLAGS>, C<FS_IOC_SETFLAGS>, C<FS_IOC_GETVERSION>, C<FS_IOC_SETVERSION>, |
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1288 | C<FS_IOC_FIEMAP>. |
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1289 | |
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1290 | C<FS_IOC_FSGETXATTR>, C<FS_IOC_FSSETXATTR>, C<FS_IOC_SET_ENCRYPTION_POLICY>, |
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1291 | C<FS_IOC_GET_ENCRYPTION_PWSALT>, C<FS_IOC_GET_ENCRYPTION_POLICY>, C<FS_KEY_DESCRIPTOR_SIZE>. |
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1292 | |
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1293 | C<FS_SECRM_FL>, C<FS_UNRM_FL>, C<FS_COMPR_FL>, C<FS_SYNC_FL>, C<FS_IMMUTABLE_FL>, |
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1294 | C<FS_APPEND_FL>, C<FS_NODUMP_FL>, C<FS_NOATIME_FL>, C<FS_DIRTY_FL>, |
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1295 | C<FS_COMPRBLK_FL>, C<FS_NOCOMP_FL>, C<FS_ENCRYPT_FL>, C<FS_BTREE_FL>, |
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1296 | C<FS_INDEX_FL>, C<FS_JOURNAL_DATA_FL>, C<FS_NOTAIL_FL>, C<FS_DIRSYNC_FL>, C<FS_TOPDIR_FL>, |
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1297 | C<FS_FL_USER_MODIFIABLE>. |
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1298 | |
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1299 | C<FS_XFLAG_REALTIME>, C<FS_XFLAG_PREALLOC>, C<FS_XFLAG_IMMUTABLE>, C<FS_XFLAG_APPEND>, |
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1300 | C<FS_XFLAG_SYNC>, C<FS_XFLAG_NOATIME>, C<FS_XFLAG_NODUMP>, C<FS_XFLAG_RTINHERIT>, |
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1301 | C<FS_XFLAG_PROJINHERIT>, C<FS_XFLAG_NOSYMLINKS>, C<FS_XFLAG_EXTSIZE>, C<FS_XFLAG_EXTSZINHERIT>, |
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1302 | C<FS_XFLAG_NODEFRAG>, C<FS_XFLAG_FILESTREAM>, C<FS_XFLAG_DAX>, C<FS_XFLAG_HASATTR>, |
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1303 | |
1232 | =item aio_sync $callback->($status) |
1304 | =item aio_sync $callback->($status) |
1233 | |
1305 | |
1234 | Asynchronously call sync and call the callback when finished. |
1306 | Asynchronously call sync and call the callback when finished. |
1235 | |
1307 | |
1236 | =item aio_fsync $fh, $callback->($status) |
1308 | =item aio_fsync $fh, $callback->($status) |
… | |
… | |
1304 | }; |
1376 | }; |
1305 | |
1377 | |
1306 | $grp |
1378 | $grp |
1307 | } |
1379 | } |
1308 | |
1380 | |
1309 | =item aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
1381 | =item aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status) |
1310 | |
1382 | |
1311 | This is a rather advanced IO::AIO call, which only works on mmap(2)ed |
1383 | This is a rather advanced IO::AIO call, which only works on mmap(2)ed |
1312 | scalars (see the C<IO::AIO::mmap> function, although it also works on data |
1384 | scalars (see the C<IO::AIO::mmap> function, although it also works on data |
1313 | scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the |
1385 | scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the |
1314 | scalar must only be modified in-place while an aio operation is pending on |
1386 | scalar must only be modified in-place while an aio operation is pending on |
… | |
… | |
1316 | |
1388 | |
1317 | It calls the C<msync> function of your OS, if available, with the memory |
1389 | It calls the C<msync> function of your OS, if available, with the memory |
1318 | area starting at C<$offset> in the string and ending C<$length> bytes |
1390 | area starting at C<$offset> in the string and ending C<$length> bytes |
1319 | later. If C<$length> is negative, counts from the end, and if C<$length> |
1391 | later. If C<$length> is negative, counts from the end, and if C<$length> |
1320 | is C<undef>, then it goes till the end of the string. The flags can be |
1392 | is C<undef>, then it goes till the end of the string. The flags can be |
1321 | a combination of C<IO::AIO::MS_ASYNC>, C<IO::AIO::MS_INVALIDATE> and |
1393 | either C<IO::AIO::MS_ASYNC> or C<IO::AIO::MS_SYNC>, plus an optional |
1322 | C<IO::AIO::MS_SYNC>. |
1394 | C<IO::AIO::MS_INVALIDATE>. |
1323 | |
1395 | |
1324 | =item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
1396 | =item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
1325 | |
1397 | |
1326 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
1398 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
1327 | scalars. |
1399 | scalars. |
… | |
… | |
1939 | This is a very bad function to use in interactive programs because it |
2011 | This is a very bad function to use in interactive programs because it |
1940 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
2012 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
1941 | use an C<aio_group> together with a feed callback. |
2013 | use an C<aio_group> together with a feed callback. |
1942 | |
2014 | |
1943 | Its main use is in scripts without an event loop - when you want to stat |
2015 | Its main use is in scripts without an event loop - when you want to stat |
1944 | a lot of files, you can write somehting like this: |
2016 | a lot of files, you can write something like this: |
1945 | |
2017 | |
1946 | IO::AIO::max_outstanding 32; |
2018 | IO::AIO::max_outstanding 32; |
1947 | |
2019 | |
1948 | for my $path (...) { |
2020 | for my $path (...) { |
1949 | aio_stat $path , ...; |
2021 | aio_stat $path , ...; |
… | |
… | |
1994 | some "Advanced I/O" function not available to in Perl, without going the |
2066 | some "Advanced I/O" function not available to in Perl, without going the |
1995 | "Asynchronous I/O" route. Many of these have an asynchronous C<aio_*> |
2067 | "Asynchronous I/O" route. Many of these have an asynchronous C<aio_*> |
1996 | counterpart. |
2068 | counterpart. |
1997 | |
2069 | |
1998 | =over 4 |
2070 | =over 4 |
|
|
2071 | |
|
|
2072 | =item $numfd = IO::AIO::get_fdlimit |
|
|
2073 | |
|
|
2074 | Tries to find the current file descriptor limit and returns it, or |
|
|
2075 | C<undef> and sets C<$!> in case of an error. The limit is one larger than |
|
|
2076 | the highest valid file descriptor number. |
|
|
2077 | |
|
|
2078 | =item IO::AIO::min_fdlimit [$numfd] |
|
|
2079 | |
|
|
2080 | Try to increase the current file descriptor limit(s) to at least C<$numfd> |
|
|
2081 | by changing the soft or hard file descriptor resource limit. If C<$numfd> |
|
|
2082 | is missing, it will try to set a very high limit, although this is not |
|
|
2083 | recommended when you know the actual minimum that you require. |
|
|
2084 | |
|
|
2085 | If the limit cannot be raised enough, the function makes a best-effort |
|
|
2086 | attempt to increase the limit as much as possible, using various |
|
|
2087 | tricks, while still failing. You can query the resulting limit using |
|
|
2088 | C<IO::AIO::get_fdlimit>. |
|
|
2089 | |
|
|
2090 | If an error occurs, returns C<undef> and sets C<$!>, otherwise returns |
|
|
2091 | true. |
1999 | |
2092 | |
2000 | =item IO::AIO::sendfile $ofh, $ifh, $offset, $count |
2093 | =item IO::AIO::sendfile $ofh, $ifh, $offset, $count |
2001 | |
2094 | |
2002 | Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>, |
2095 | Calls the C<eio_sendfile_sync> function, which is like C<aio_sendfile>, |
2003 | but is blocking (this makes most sense if you know the input data is |
2096 | but is blocking (this makes most sense if you know the input data is |
… | |
… | |
2020 | =item IO::AIO::madvise $scalar, $offset, $len, $advice |
2113 | =item IO::AIO::madvise $scalar, $offset, $len, $advice |
2021 | |
2114 | |
2022 | Simply calls the C<posix_madvise> function (see its |
2115 | Simply calls the C<posix_madvise> function (see its |
2023 | manpage for details). The following advice constants are |
2116 | manpage for details). The following advice constants are |
2024 | available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>, |
2117 | available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>, |
2025 | C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>. |
2118 | C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, |
|
|
2119 | C<IO::AIO::MADV_DONTNEED>. |
|
|
2120 | |
|
|
2121 | If C<$offset> is negative, counts from the end. If C<$length> is negative, |
|
|
2122 | the remaining length of the C<$scalar> is used. If possible, C<$length> |
|
|
2123 | will be reduced to fit into the C<$scalar>. |
2026 | |
2124 | |
2027 | On systems that do not implement C<posix_madvise>, this function returns |
2125 | On systems that do not implement C<posix_madvise>, this function returns |
2028 | ENOSYS, otherwise the return value of C<posix_madvise>. |
2126 | ENOSYS, otherwise the return value of C<posix_madvise>. |
2029 | |
2127 | |
2030 | =item IO::AIO::mprotect $scalar, $offset, $len, $protect |
2128 | =item IO::AIO::mprotect $scalar, $offset, $len, $protect |
… | |
… | |
2032 | Simply calls the C<mprotect> function on the preferably AIO::mmap'ed |
2130 | Simply calls the C<mprotect> function on the preferably AIO::mmap'ed |
2033 | $scalar (see its manpage for details). The following protect |
2131 | $scalar (see its manpage for details). The following protect |
2034 | constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>, |
2132 | constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>, |
2035 | C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>. |
2133 | C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>. |
2036 | |
2134 | |
|
|
2135 | If C<$offset> is negative, counts from the end. If C<$length> is negative, |
|
|
2136 | the remaining length of the C<$scalar> is used. If possible, C<$length> |
|
|
2137 | will be reduced to fit into the C<$scalar>. |
|
|
2138 | |
2037 | On systems that do not implement C<mprotect>, this function returns |
2139 | On systems that do not implement C<mprotect>, this function returns |
2038 | ENOSYS, otherwise the return value of C<mprotect>. |
2140 | ENOSYS, otherwise the return value of C<mprotect>. |
2039 | |
2141 | |
2040 | =item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
2142 | =item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
2041 | |
2143 | |
2042 | Memory-maps a file (or anonymous memory range) and attaches it to the |
2144 | Memory-maps a file (or anonymous memory range) and attaches it to the |
2043 | given C<$scalar>, which will act like a string scalar. Returns true on |
2145 | given C<$scalar>, which will act like a string scalar. Returns true on |
2044 | success, and false otherwise. |
2146 | success, and false otherwise. |
2045 | |
2147 | |
|
|
2148 | The scalar must exist, but its contents do not matter - this means you |
|
|
2149 | cannot use a nonexistant array or hash element. When in doubt, C<undef> |
|
|
2150 | the scalar first. |
|
|
2151 | |
2046 | The only operations allowed on the scalar are C<substr>/C<vec> that don't |
2152 | The only operations allowed on the mmapped scalar are C<substr>/C<vec>, |
2047 | change the string length, and most read-only operations such as copying it |
2153 | which don't change the string length, and most read-only operations such |
2048 | or searching it with regexes and so on. |
2154 | as copying it or searching it with regexes and so on. |
2049 | |
2155 | |
2050 | Anything else is unsafe and will, at best, result in memory leaks. |
2156 | Anything else is unsafe and will, at best, result in memory leaks. |
2051 | |
2157 | |
2052 | The memory map associated with the C<$scalar> is automatically removed |
2158 | The memory map associated with the C<$scalar> is automatically removed |
2053 | when the C<$scalar> is destroyed, or when the C<IO::AIO::mmap> or |
2159 | when the C<$scalar> is undef'd or destroyed, or when the C<IO::AIO::mmap> |
2054 | C<IO::AIO::munmap> functions are called. |
2160 | or C<IO::AIO::munmap> functions are called on it. |
2055 | |
2161 | |
2056 | This calls the C<mmap>(2) function internally. See your system's manual |
2162 | This calls the C<mmap>(2) function internally. See your system's manual |
2057 | page for details on the C<$length>, C<$prot> and C<$flags> parameters. |
2163 | page for details on the C<$length>, C<$prot> and C<$flags> parameters. |
2058 | |
2164 | |
2059 | The C<$length> must be larger than zero and smaller than the actual |
2165 | The C<$length> must be larger than zero and smaller than the actual |
… | |
… | |
2065 | C<$flags> can be a combination of |
2171 | C<$flags> can be a combination of |
2066 | C<IO::AIO::MAP_SHARED> or |
2172 | C<IO::AIO::MAP_SHARED> or |
2067 | C<IO::AIO::MAP_PRIVATE>, |
2173 | C<IO::AIO::MAP_PRIVATE>, |
2068 | or a number of system-specific flags (when not available, the are C<0>): |
2174 | or a number of system-specific flags (when not available, the are C<0>): |
2069 | C<IO::AIO::MAP_ANONYMOUS> (which is set to C<MAP_ANON> if your system only provides this constant), |
2175 | C<IO::AIO::MAP_ANONYMOUS> (which is set to C<MAP_ANON> if your system only provides this constant), |
2070 | C<IO::AIO::MAP_HUGETLB>, |
|
|
2071 | C<IO::AIO::MAP_LOCKED>, |
2176 | C<IO::AIO::MAP_LOCKED>, |
2072 | C<IO::AIO::MAP_NORESERVE>, |
2177 | C<IO::AIO::MAP_NORESERVE>, |
2073 | C<IO::AIO::MAP_POPULATE>, |
2178 | C<IO::AIO::MAP_POPULATE>, |
2074 | C<IO::AIO::MAP_NONBLOCK>, |
2179 | C<IO::AIO::MAP_NONBLOCK>, |
2075 | C<IO::AIO::MAP_FIXED>, |
2180 | C<IO::AIO::MAP_FIXED>, |