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Comparing IO-AIO/AIO.pm (file contents):
Revision 1.208 by root, Mon Sep 26 20:19:08 2011 UTC vs.
Revision 1.209 by root, Tue Sep 27 00:41:51 2011 UTC

… …
221 aio_utime $fh_or_path, $atime, $mtime, $callback->($status) 221 aio_utime $fh_or_path, $atime, $mtime, $callback->($status)
222 aio_chown $fh_or_path, $uid, $gid, $callback->($status) 222 aio_chown $fh_or_path, $uid, $gid, $callback->($status)
223 aio_truncate $fh_or_path, $offset, $callback->($status) 223 aio_truncate $fh_or_path, $offset, $callback->($status)
224 aio_chmod $fh_or_path, $mode, $callback->($status) 224 aio_chmod $fh_or_path, $mode, $callback->($status)
225 aio_unlink $pathname, $callback->($status) 225 aio_unlink $pathname, $callback->($status)
226 aio_mknod $path, $mode, $dev, $callback->($status) 226 aio_mknod $pathname, $mode, $dev, $callback->($status)
227 aio_link $srcpath, $dstpath, $callback->($status) 227 aio_link $srcpath, $dstpath, $callback->($status)
228 aio_symlink $srcpath, $dstpath, $callback->($status) 228 aio_symlink $srcpath, $dstpath, $callback->($status)
229 aio_readlink $path, $callback->($link) 229 aio_readlink $pathname, $callback->($link)
230 aio_realpath $path, $callback->($link) 230 aio_realpath $pathname, $callback->($link)
231 aio_rename $srcpath, $dstpath, $callback->($status) 231 aio_rename $srcpath, $dstpath, $callback->($status)
232 aio_mkdir $pathname, $mode, $callback->($status) 232 aio_mkdir $pathname, $mode, $callback->($status)
233 aio_rmdir $pathname, $callback->($status) 233 aio_rmdir $pathname, $callback->($status)
234 aio_readdir $pathname, $callback->($entries) 234 aio_readdir $pathname, $callback->($entries)
235 aio_readdirx $pathname, $flags, $callback->($entries, $flags) 235 aio_readdirx $pathname, $flags, $callback->($entries, $flags)
236 IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST 236 IO::AIO::READDIR_DENTS IO::AIO::READDIR_DIRS_FIRST
237 IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN 237 IO::AIO::READDIR_STAT_ORDER IO::AIO::READDIR_FOUND_UNKNOWN
238 aio_load $path, $data, $callback->($status) 238 aio_load $pathname, $data, $callback->($status)
239 aio_copy $srcpath, $dstpath, $callback->($status) 239 aio_copy $srcpath, $dstpath, $callback->($status)
240 aio_move $srcpath, $dstpath, $callback->($status) 240 aio_move $srcpath, $dstpath, $callback->($status)
241 aio_scandir $path, $maxreq, $callback->($dirs, $nondirs) 241 aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
242 aio_rmtree $path, $callback->($status) 242 aio_rmtree $pathname, $callback->($status)
243 aio_sync $callback->($status) 243 aio_sync $callback->($status)
244 aio_syncfs $fh, $callback->($status) 244 aio_syncfs $fh, $callback->($status)
245 aio_fsync $fh, $callback->($status) 245 aio_fsync $fh, $callback->($status)
246 aio_fdatasync $fh, $callback->($status) 246 aio_fdatasync $fh, $callback->($status)
247 aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status) 247 aio_sync_file_range $fh, $offset, $nbytes, $flags, $callback->($status)
248 aio_pathsync $path, $callback->($status) 248 aio_pathsync $pathname, $callback->($status)
249 aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) 249 aio_msync $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
250 aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status) 250 aio_mtouch $scalar, $offset = 0, $length = undef, flags = 0, $callback->($status)
251 aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status) 251 aio_mlock $scalar, $offset = 0, $length = undef, $callback->($status)
252 aio_mlockall $flags, $callback->($status) 252 aio_mlockall $flags, $callback->($status)
253 aio_group $callback->(...) 253 aio_group $callback->(...)
… …
292internally until the request has finished. 292internally until the request has finished.
293 293
294All functions return request objects of type L<IO::AIO::REQ> that allow 294All functions return request objects of type L<IO::AIO::REQ> that allow
295further manipulation of those requests while they are in-flight. 295further manipulation of those requests while they are in-flight.
296 296
297The pathnames you pass to these routines I<must> be absolute and 297The pathnames you pass to these routines I<should> be absolute. The
298encoded as octets. The reason for the former is that at the time the 298reason for this is that at the time the request is being executed, the
299request is being executed, the current working directory could have 299current working directory could have changed. Alternatively, you can make
300changed. Alternatively, you can make sure that you never change the 300sure that you never change the current working directory anywhere in
301current working directory anywhere in the program and then use relative 301the program and then use relative paths. Lastly, you can take advantage
302paths. 302of IO::AIOs working directory abstraction - see the description of the
303C<IO::AIO::WD> class later in this document.
303 304
304To encode pathnames as octets, either make sure you either: a) always pass 305To encode pathnames as octets, either make sure you either: a) always pass
305in filenames you got from outside (command line, readdir etc.) without 306in filenames you got from outside (command line, readdir etc.) without
306tinkering, b) are ASCII or ISO 8859-1, c) use the Encode module and encode 307tinkering, b) are ASCII or ISO 8859-1, c) use the Encode module and encode
307your pathnames to the locale (or other) encoding in effect in the user 308your pathnames to the locale (or other) encoding in effect in the user
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616 617
617Asynchronously unlink (delete) a file and call the callback with the 618Asynchronously unlink (delete) a file and call the callback with the
618result code. 619result code.
619 620
620 621
621=item aio_mknod $path, $mode, $dev, $callback->($status) 622=item aio_mknod $pathname, $mode, $dev, $callback->($status)
622 623
623[EXPERIMENTAL] 624[EXPERIMENTAL]
624 625
625Asynchronously create a device node (or fifo). See mknod(2). 626Asynchronously create a device node (or fifo). See mknod(2).
626 627
627The only (POSIX-) portable way of calling this function is: 628The only (POSIX-) portable way of calling this function is:
628 629
629 aio_mknod $path, IO::AIO::S_IFIFO | $mode, 0, sub { ... 630 aio_mknod $pathname, IO::AIO::S_IFIFO | $mode, 0, sub { ...
630 631
631See C<aio_stat> for info about some potentially helpful extra constants 632See C<aio_stat> for info about some potentially helpful extra constants
632and functions. 633and functions.
633 634
634=item aio_link $srcpath, $dstpath, $callback->($status) 635=item aio_link $srcpath, $dstpath, $callback->($status)
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641 642
642Asynchronously create a new symbolic link to the existing object at C<$srcpath> at 643Asynchronously create a new symbolic link to the existing object at C<$srcpath> at
643the path C<$dstpath> and call the callback with the result code. 644the path C<$dstpath> and call the callback with the result code.
644 645
645 646
646=item aio_readlink $path, $callback->($link) 647=item aio_readlink $pathname, $callback->($link)
647 648
648Asynchronously read the symlink specified by C<$path> and pass it to 649Asynchronously read the symlink specified by C<$path> and pass it to
649the callback. If an error occurs, nothing or undef gets passed to the 650the callback. If an error occurs, nothing or undef gets passed to the
650callback. 651callback.
651 652
652 653
653=item aio_realpath $path, $callback->($path) 654=item aio_realpath $pathname, $callback->($path)
654 655
655Asynchronously make the path absolute and resolve any symlinks in 656Asynchronously make the path absolute and resolve any symlinks in
656C<$path>. The resulting path only consists of directories (Same as 657C<$path>. The resulting path only consists of directories (Same as
657L<Cwd::realpath>). 658L<Cwd::realpath>).
658 659
… …
753C<$type>'s are known, which can be used to speed up some algorithms. 754C<$type>'s are known, which can be used to speed up some algorithms.
754 755
755=back 756=back
756 757
757 758
758=item aio_load $path, $data, $callback->($status) 759=item aio_load $pathname, $data, $callback->($status)
759 760
760This is a composite request that tries to fully load the given file into 761This is a composite request that tries to fully load the given file into
761memory. Status is the same as with aio_read. 762memory. Status is the same as with aio_read.
762 763
763=cut 764=cut
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898 }; 899 };
899 900
900 $grp 901 $grp
901} 902}
902 903
903=item aio_scandir $path, $maxreq, $callback->($dirs, $nondirs) 904=item aio_scandir $pathname, $maxreq, $callback->($dirs, $nondirs)
904 905
905Scans a directory (similar to C<aio_readdir>) but additionally tries to 906Scans a directory (similar to C<aio_readdir>) but additionally tries to
906efficiently separate the entries of directory C<$path> into two sets of 907efficiently separate the entries of directory C<$path> into two sets of
907names, directories you can recurse into (directories), and ones you cannot 908names, directories you can recurse into (directories), and ones you cannot
908recurse into (everything else, including symlinks to directories). 909recurse into (everything else, including symlinks to directories).
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1035 }; 1036 };
1036 1037
1037 $grp 1038 $grp
1038} 1039}
1039 1040
1040=item aio_rmtree $path, $callback->($status) 1041=item aio_rmtree $pathname, $callback->($status)
1041 1042
1042Delete a directory tree starting (and including) C<$path>, return the 1043Delete a directory tree starting (and including) C<$path>, return the
1043status of the final C<rmdir> only. This is a composite request that 1044status of the final C<rmdir> only. This is a composite request that
1044uses C<aio_scandir> to recurse into and rmdir directories, and unlink 1045uses C<aio_scandir> to recurse into and rmdir directories, and unlink
1045everything else. 1046everything else.
… …
1106C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>, 1107C<$flags> can be a combination of C<IO::AIO::SYNC_FILE_RANGE_WAIT_BEFORE>,
1107C<IO::AIO::SYNC_FILE_RANGE_WRITE> and 1108C<IO::AIO::SYNC_FILE_RANGE_WRITE> and
1108C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range 1109C<IO::AIO::SYNC_FILE_RANGE_WAIT_AFTER>: refer to the sync_file_range
1109manpage for details. 1110manpage for details.
1110 1111
1111=item aio_pathsync $path, $callback->($status) 1112=item aio_pathsync $pathname, $callback->($status)
1112 1113
1113This request tries to open, fsync and close the given path. This is a 1114This request tries to open, fsync and close the given path. This is a
1114composite request intended to sync directories after directory operations 1115composite request intended to sync directories after directory operations
1115(E.g. rename). This might not work on all operating systems or have any 1116(E.g. rename). This might not work on all operating systems or have any
1116specific effect, but usually it makes sure that directory changes get 1117specific effect, but usually it makes sure that directory changes get
… …
1259immense (it blocks a thread for a long time) so do not use this function 1260immense (it blocks a thread for a long time) so do not use this function
1260except to put your application under artificial I/O pressure. 1261except to put your application under artificial I/O pressure.
1261 1262
1262=back 1263=back
1263 1264
1265
1266=head2 IO::AIO::WD - multiple working directories
1267
1268Your process only has one current working directory, which is used by all
1269threads. This makes it hard to use relative paths (some other component
1270could call C<chdir> at any time, and it is hard to control when the path
1271will be used by IO::AIO).
1272
1273One solution for this is to always use absolute paths. This usually works,
1274but can be quite slow (the kernel has to walk the whole path on every
1275access), and can also be a hassle to implement.
1276
1277Newer POSIX systems have a number of functions (openat, fdopendir,
1278futimensat and so on) that make it possible to specify working directories
1279per operation.
1280
1281For portability, and because the clowns who "designed", or shall I write,
1282perpetrated this new interface were obviously half-drunk, this abstraction
1283cannot be perfect, though.
1284
1285IO::AIO allows you to convert directory paths into a so-called IO::AIO::WD
1286object. This object stores the canonicalised, absolute version of the
1287path, and on systems that allow it, also a directory file descriptor.
1288
1289Everywhere where a pathname is accepted by IO::AIO (e.g. in C<aio_stat>
1290or C<aio_unlink>), one can specify an array reference with an IO::AIO::WD
1291object and a pathname instead. If the pathname is absolute, the
1292IO::AIO::WD objetc is ignored, otherwise the pathname is resolved relative
1293to that IO::AIO::WD object.
1294
1295For example, to get a wd object for F</etc> and then stat F<passwd>
1296inside, you would write:
1297
1298 aio_wd "/etc", sub {
1299 my $etcdir = shift;
1300
1301 # although $etcdir can be undef on error, there is generally no reason
1302 # to check for errors here, as aio_stat will fail with ENOENT
1303 # when $etcdir is undef.
1304
1305 aio_stat [$etcdir, "passwd"], sub {
1306 # yay
1307 };
1308 };
1309
1310This shows that creating an IO::AIO::WD object is itself a potentially
1311blocking operation, which is why it is done asynchronously.
1312
1313As with normal pathnames, IO::AIO keeps a copy of the working directory
1314object and the pathname string, so you could write the following without
1315causing any issues due to C<$path> getting reused:
1316
1317 my $path = [$wd, undef];
1318
1319 for my $name (qw(abc def ghi)) {
1320 $path->[1] = $name;
1321 aio_stat $path, sub {
1322 # ...
1323 };
1324 }
1325
1326There are some caveats: when directories get renamed (or deleted), the
1327pathname string doesn't change, so will point to the new directory (or
1328nowhere at all), while the directory fd, if available on the system,
1329will still point to the original directory. Most functions accepting a
1330pathname will use the directory fd on newer systems, and the string on
1331older systems. Some functions (such as realpath) will always rely on the
1332string form of the pathname.
1333
1334So this fucntionality is mainly useful to get some protection against
1335C<chdir>, to easily get an absolute path out of a relative path for future
1336reference, and to speed up doing many operations in the same directory
1337(e.g. when stat'ing all files in a directory).
1338
1339The following functions implement this working directory abstraction:
1340
1341=over 4
1342
1343=item aio_wd $pathname, $callback->($wd)
1344
1345Asynchonously canonicalise the given pathname and convert it to an
1346IO::AIO::WD object representing it. If possible and supported on the
1347system, also open a directory fd to speed up pathname resolution relative
1348to this working directory.
1349
1350If something goes wrong, then C<undef> is passwd to the callback instead
1351of a working directory object and C<$!> is set appropriately. Since
1352passing C<undef> as working directory component of a pathname fails the
1353request with C<ENOENT>, there is often no need for error checking in the
1354C<aio_wd> callback, as future requests using the value will fail in the
1355expected way.
1356
1357If this call isn't available because your OS lacks it or it couldn't be
1358detected, it will be emulated by calling C<fsync> instead.
1359
1360=item IO::AIO::CWD
1361
1362This is a compiletime constant (object) that represents the process
1363current working directory.
1364
1365Specifying this object as working directory object for a pathname is as
1366if the pathname would be specified directly, without a directory object,
1367e.g., these calls are functionally identical:
1368
1369 aio_stat "somefile", sub { ... };
1370 aio_stat [IO::AIO::CWD, "somefile"], sub { ... };
1371
1372=back
1373
1374
1264=head2 IO::AIO::REQ CLASS 1375=head2 IO::AIO::REQ CLASS
1265 1376
1266All non-aggregate C<aio_*> functions return an object of this class when 1377All non-aggregate C<aio_*> functions return an object of this class when
1267called in non-void context. 1378called in non-void context.
1268 1379

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