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 = 4.34; |
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_fcntl aio_ioctl |
180 | aio_scandir aio_symlink aio_readlink aio_realpath aio_fcntl aio_ioctl |
177 | aio_sync aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range |
181 | aio_sync aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range |
178 | aio_pathsync aio_readahead aio_fiemap aio_allocate |
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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248 | aio_syncfs $fh, $callback->($status) |
253 | aio_syncfs $fh, $callback->($status) |
249 | aio_fsync $fh, $callback->($status) |
254 | aio_fsync $fh, $callback->($status) |
250 | aio_fdatasync $fh, $callback->($status) |
255 | aio_fdatasync $fh, $callback->($status) |
251 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
256 | aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) |
252 | aio_pathsync $pathname, $callback->($status) |
257 | aio_pathsync $pathname, $callback->($status) |
253 | aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
258 | aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status) |
254 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
259 | aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
255 | aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
260 | aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) |
256 | aio_mlockall $flags, $callback->($status) |
261 | aio_mlockall $flags, $callback->($status) |
257 | aio_group $callback->(...) |
262 | aio_group $callback->(...) |
258 | aio_nop $callback->() |
263 | aio_nop $callback->() |
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441 | =item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
446 | =item aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
442 | |
447 | |
443 | =item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
448 | =item aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
444 | |
449 | |
445 | Reads or writes C<$length> bytes from or to the specified C<$fh> and |
450 | Reads or writes C<$length> bytes from or to the specified C<$fh> and |
446 | C<$offset> into the scalar given by C<$data> and offset C<$dataoffset> |
451 | C<$offset> into the scalar given by C<$data> and offset C<$dataoffset> and |
447 | and calls the callback without the actual number of bytes read (or -1 on |
452 | calls the callback with the actual number of bytes transferred (or -1 on |
448 | error, just like the syscall). |
453 | error, just like the syscall). |
449 | |
454 | |
450 | C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to |
455 | C<aio_read> will, like C<sysread>, shrink or grow the C<$data> scalar to |
451 | offset plus the actual number of bytes read. |
456 | offset plus the actual number of bytes read. |
452 | |
457 | |
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735 | C<$mode> is usually C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> to allocate |
740 | C<$mode> is usually C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> to allocate |
736 | space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE | IO::AIO::FALLOC_FL_KEEP_SIZE>, |
741 | space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE | IO::AIO::FALLOC_FL_KEEP_SIZE>, |
737 | to deallocate a file range. |
742 | to deallocate a file range. |
738 | |
743 | |
739 | IO::AIO also supports C<FALLOC_FL_COLLAPSE_RANGE>, to remove a range |
744 | IO::AIO also supports C<FALLOC_FL_COLLAPSE_RANGE>, to remove a range |
740 | (without leaving a hole) and C<FALLOC_FL_ZERO_RANGE>, to zero a range (see |
745 | (without leaving a hole), C<FALLOC_FL_ZERO_RANGE>, to zero a range, |
741 | your L<fallocate(2)> manpage). |
746 | C<FALLOC_FL_INSERT_RANGE> to insert a range and C<FALLOC_FL_UNSHARE_RANGE> |
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747 | to unshare shared blocks (see your L<fallocate(2)> manpage). |
742 | |
748 | |
743 | The file system block size used by C<fallocate> is presumably the |
749 | The file system block size used by C<fallocate> is presumably the |
744 | C<f_bsize> returned by C<statvfs>. |
750 | C<f_bsize> returned by C<statvfs>, but different filesystems and filetypes |
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751 | can dictate other limitations. |
745 | |
752 | |
746 | If C<fallocate> isn't available or cannot be emulated (currently no |
753 | If C<fallocate> isn't available or cannot be emulated (currently no |
747 | emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>. |
754 | emulation will be attempted), passes C<-1> and sets C<$!> to C<ENOSYS>. |
748 | |
755 | |
749 | |
756 | |
… | |
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806 | rename(2) and call the callback with the result code. |
813 | rename(2) and call the callback with the result code. |
807 | |
814 | |
808 | On systems that support the AIO::WD working directory abstraction |
815 | On systems that support the AIO::WD working directory abstraction |
809 | natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead |
816 | natively, the case C<[$wd, "."]> as C<$srcpath> is specialcased - instead |
810 | of failing, C<rename> is called on the absolute path of C<$wd>. |
817 | of failing, C<rename> is called on the absolute path of C<$wd>. |
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818 | |
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819 | |
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820 | =item aio_rename2 $srcpath, $dstpath, $flags, $callback->($status) |
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821 | |
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822 | Basically a version of C<aio_rename> with an additional C<$flags> |
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823 | argument. Calling this with C<$flags=0> is the same as calling |
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824 | C<aio_rename>. |
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825 | |
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826 | Non-zero flags are currently only supported on GNU/Linux systems that |
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827 | support renameat2. Other systems fail with C<ENOSYS> in this case. |
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828 | |
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829 | The following constants are available (missing ones are, as usual C<0>), |
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830 | see renameat2(2) for details: |
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831 | |
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832 | C<IO::AIO::RENAME_NOREPLACE>, C<IO::AIO::RENAME_EXCHANGE> |
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833 | and C<IO::AIO::RENAME_WHITEOUT>. |
811 | |
834 | |
812 | |
835 | |
813 | =item aio_mkdir $pathname, $mode, $callback->($status) |
836 | =item aio_mkdir $pathname, $mode, $callback->($status) |
814 | |
837 | |
815 | Asynchronously mkdir (create) a directory and call the callback with |
838 | Asynchronously mkdir (create) a directory and call the callback with |
… | |
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1248 | So in general, you should only use these calls for things that do |
1271 | So in general, you should only use these calls for things that do |
1249 | (filesystem) I/O, not for things that wait for other events (network, |
1272 | (filesystem) I/O, not for things that wait for other events (network, |
1250 | other processes), although if you are careful and know what you are doing, |
1273 | other processes), although if you are careful and know what you are doing, |
1251 | you still can. |
1274 | you still can. |
1252 | |
1275 | |
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1276 | The following constants are available (missing ones are, as usual C<0>): |
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1277 | |
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1278 | C<F_DUPFD_CLOEXEC>, |
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1279 | |
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1280 | C<F_OFD_GETLK>, C<F_OFD_SETLK>, C<F_OFD_GETLKW>, |
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1281 | |
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1282 | C<FIFREEZE>, C<FITHAW>, C<FITRIM>, C<FICLONE>, C<FICLONERANGE>, C<FIDEDUPERANGE>. |
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1283 | |
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1284 | C<FS_IOC_GETFLAGS>, C<FS_IOC_SETFLAGS>, C<FS_IOC_GETVERSION>, C<FS_IOC_SETVERSION>, |
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1285 | C<FS_IOC_FIEMAP>. |
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1286 | |
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1287 | C<FS_IOC_FSGETXATTR>, C<FS_IOC_FSSETXATTR>, C<FS_IOC_SET_ENCRYPTION_POLICY>, |
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1288 | C<FS_IOC_GET_ENCRYPTION_PWSALT>, C<FS_IOC_GET_ENCRYPTION_POLICY>, C<FS_KEY_DESCRIPTOR_SIZE>. |
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1289 | |
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1290 | C<FS_SECRM_FL>, C<FS_UNRM_FL>, C<FS_COMPR_FL>, C<FS_SYNC_FL>, C<FS_IMMUTABLE_FL>, |
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1291 | C<FS_APPEND_FL>, C<FS_NODUMP_FL>, C<FS_NOATIME_FL>, C<FS_DIRTY_FL>, |
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1292 | C<FS_COMPRBLK_FL>, C<FS_NOCOMP_FL>, C<FS_ENCRYPT_FL>, C<FS_BTREE_FL>, |
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1293 | 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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1294 | C<FS_FL_USER_MODIFIABLE>. |
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1295 | |
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1296 | C<FS_XFLAG_REALTIME>, C<FS_XFLAG_PREALLOC>, C<FS_XFLAG_IMMUTABLE>, C<FS_XFLAG_APPEND>, |
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1297 | C<FS_XFLAG_SYNC>, C<FS_XFLAG_NOATIME>, C<FS_XFLAG_NODUMP>, C<FS_XFLAG_RTINHERIT>, |
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1298 | C<FS_XFLAG_PROJINHERIT>, C<FS_XFLAG_NOSYMLINKS>, C<FS_XFLAG_EXTSIZE>, C<FS_XFLAG_EXTSZINHERIT>, |
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1299 | C<FS_XFLAG_NODEFRAG>, C<FS_XFLAG_FILESTREAM>, C<FS_XFLAG_DAX>, C<FS_XFLAG_HASATTR>, |
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1300 | |
1253 | =item aio_sync $callback->($status) |
1301 | =item aio_sync $callback->($status) |
1254 | |
1302 | |
1255 | Asynchronously call sync and call the callback when finished. |
1303 | Asynchronously call sync and call the callback when finished. |
1256 | |
1304 | |
1257 | =item aio_fsync $fh, $callback->($status) |
1305 | =item aio_fsync $fh, $callback->($status) |
… | |
… | |
1325 | }; |
1373 | }; |
1326 | |
1374 | |
1327 | $grp |
1375 | $grp |
1328 | } |
1376 | } |
1329 | |
1377 | |
1330 | =item aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
1378 | =item aio_msync $scalar, $offset = 0, $length = undef, flags = MS_SYNC, $callback->($status) |
1331 | |
1379 | |
1332 | This is a rather advanced IO::AIO call, which only works on mmap(2)ed |
1380 | This is a rather advanced IO::AIO call, which only works on mmap(2)ed |
1333 | scalars (see the C<IO::AIO::mmap> function, although it also works on data |
1381 | scalars (see the C<IO::AIO::mmap> function, although it also works on data |
1334 | scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the |
1382 | scalars managed by the L<Sys::Mmap> or L<Mmap> modules, note that the |
1335 | scalar must only be modified in-place while an aio operation is pending on |
1383 | scalar must only be modified in-place while an aio operation is pending on |
… | |
… | |
1337 | |
1385 | |
1338 | It calls the C<msync> function of your OS, if available, with the memory |
1386 | It calls the C<msync> function of your OS, if available, with the memory |
1339 | area starting at C<$offset> in the string and ending C<$length> bytes |
1387 | area starting at C<$offset> in the string and ending C<$length> bytes |
1340 | later. If C<$length> is negative, counts from the end, and if C<$length> |
1388 | later. If C<$length> is negative, counts from the end, and if C<$length> |
1341 | is C<undef>, then it goes till the end of the string. The flags can be |
1389 | is C<undef>, then it goes till the end of the string. The flags can be |
1342 | a combination of C<IO::AIO::MS_ASYNC>, C<IO::AIO::MS_INVALIDATE> and |
1390 | either C<IO::AIO::MS_ASYNC> or C<IO::AIO::MS_SYNC>, plus an optional |
1343 | C<IO::AIO::MS_SYNC>. |
1391 | C<IO::AIO::MS_INVALIDATE>. |
1344 | |
1392 | |
1345 | =item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
1393 | =item aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) |
1346 | |
1394 | |
1347 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
1395 | This is a rather advanced IO::AIO call, which works best on mmap(2)ed |
1348 | scalars. |
1396 | scalars. |
… | |
… | |
1960 | This is a very bad function to use in interactive programs because it |
2008 | This is a very bad function to use in interactive programs because it |
1961 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
2009 | blocks, and a bad way to reduce concurrency because it is inexact: Better |
1962 | use an C<aio_group> together with a feed callback. |
2010 | use an C<aio_group> together with a feed callback. |
1963 | |
2011 | |
1964 | Its main use is in scripts without an event loop - when you want to stat |
2012 | Its main use is in scripts without an event loop - when you want to stat |
1965 | a lot of files, you can write somehting like this: |
2013 | a lot of files, you can write something like this: |
1966 | |
2014 | |
1967 | IO::AIO::max_outstanding 32; |
2015 | IO::AIO::max_outstanding 32; |
1968 | |
2016 | |
1969 | for my $path (...) { |
2017 | for my $path (...) { |
1970 | aio_stat $path , ...; |
2018 | aio_stat $path , ...; |
… | |
… | |
2041 | =item IO::AIO::madvise $scalar, $offset, $len, $advice |
2089 | =item IO::AIO::madvise $scalar, $offset, $len, $advice |
2042 | |
2090 | |
2043 | Simply calls the C<posix_madvise> function (see its |
2091 | Simply calls the C<posix_madvise> function (see its |
2044 | manpage for details). The following advice constants are |
2092 | manpage for details). The following advice constants are |
2045 | available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>, |
2093 | available: C<IO::AIO::MADV_NORMAL>, C<IO::AIO::MADV_SEQUENTIAL>, |
2046 | C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, C<IO::AIO::MADV_DONTNEED>. |
2094 | C<IO::AIO::MADV_RANDOM>, C<IO::AIO::MADV_WILLNEED>, |
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2095 | C<IO::AIO::MADV_DONTNEED>. |
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2096 | |
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2097 | If C<$offset> is negative, counts from the end. If C<$length> is negative, |
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2098 | the remaining length of the C<$scalar> is used. If possible, C<$length> |
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2099 | will be reduced to fit into the C<$scalar>. |
2047 | |
2100 | |
2048 | On systems that do not implement C<posix_madvise>, this function returns |
2101 | On systems that do not implement C<posix_madvise>, this function returns |
2049 | ENOSYS, otherwise the return value of C<posix_madvise>. |
2102 | ENOSYS, otherwise the return value of C<posix_madvise>. |
2050 | |
2103 | |
2051 | =item IO::AIO::mprotect $scalar, $offset, $len, $protect |
2104 | =item IO::AIO::mprotect $scalar, $offset, $len, $protect |
… | |
… | |
2053 | Simply calls the C<mprotect> function on the preferably AIO::mmap'ed |
2106 | Simply calls the C<mprotect> function on the preferably AIO::mmap'ed |
2054 | $scalar (see its manpage for details). The following protect |
2107 | $scalar (see its manpage for details). The following protect |
2055 | constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>, |
2108 | constants are available: C<IO::AIO::PROT_NONE>, C<IO::AIO::PROT_READ>, |
2056 | C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>. |
2109 | C<IO::AIO::PROT_WRITE>, C<IO::AIO::PROT_EXEC>. |
2057 | |
2110 | |
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2111 | If C<$offset> is negative, counts from the end. If C<$length> is negative, |
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2112 | the remaining length of the C<$scalar> is used. If possible, C<$length> |
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2113 | will be reduced to fit into the C<$scalar>. |
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2114 | |
2058 | On systems that do not implement C<mprotect>, this function returns |
2115 | On systems that do not implement C<mprotect>, this function returns |
2059 | ENOSYS, otherwise the return value of C<mprotect>. |
2116 | ENOSYS, otherwise the return value of C<mprotect>. |
2060 | |
2117 | |
2061 | =item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
2118 | =item IO::AIO::mmap $scalar, $length, $prot, $flags, $fh[, $offset] |
2062 | |
2119 | |
2063 | Memory-maps a file (or anonymous memory range) and attaches it to the |
2120 | Memory-maps a file (or anonymous memory range) and attaches it to the |
2064 | given C<$scalar>, which will act like a string scalar. Returns true on |
2121 | given C<$scalar>, which will act like a string scalar. Returns true on |
2065 | success, and false otherwise. |
2122 | success, and false otherwise. |
2066 | |
2123 | |
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2124 | The scalar must exist, but its contents do not matter - this means you |
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2125 | cannot use a nonexistant array or hash element. When in doubt, C<undef> |
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2126 | the scalar first. |
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2127 | |
2067 | The only operations allowed on the scalar are C<substr>/C<vec> that don't |
2128 | The only operations allowed on the mmapped scalar are C<substr>/C<vec>, |
2068 | change the string length, and most read-only operations such as copying it |
2129 | which don't change the string length, and most read-only operations such |
2069 | or searching it with regexes and so on. |
2130 | as copying it or searching it with regexes and so on. |
2070 | |
2131 | |
2071 | Anything else is unsafe and will, at best, result in memory leaks. |
2132 | Anything else is unsafe and will, at best, result in memory leaks. |
2072 | |
2133 | |
2073 | The memory map associated with the C<$scalar> is automatically removed |
2134 | The memory map associated with the C<$scalar> is automatically removed |
2074 | when the C<$scalar> is destroyed, or when the C<IO::AIO::mmap> or |
2135 | when the C<$scalar> is undef'd or destroyed, or when the C<IO::AIO::mmap> |
2075 | C<IO::AIO::munmap> functions are called. |
2136 | or C<IO::AIO::munmap> functions are called on it. |
2076 | |
2137 | |
2077 | This calls the C<mmap>(2) function internally. See your system's manual |
2138 | This calls the C<mmap>(2) function internally. See your system's manual |
2078 | page for details on the C<$length>, C<$prot> and C<$flags> parameters. |
2139 | page for details on the C<$length>, C<$prot> and C<$flags> parameters. |
2079 | |
2140 | |
2080 | The C<$length> must be larger than zero and smaller than the actual |
2141 | The C<$length> must be larger than zero and smaller than the actual |