ViewVC Help
View File | Revision Log | Show Annotations | Download File
/cvs/IO-AIO/AIO.pm
(Generate patch)

Comparing IO-AIO/AIO.pm (file contents):
Revision 1.244 by root, Fri Jan 24 23:46:16 2014 UTC vs.
Revision 1.253 by root, Thu Jun 25 13:34:28 2015 UTC

167use common::sense; 167use common::sense;
168 168
169use base 'Exporter'; 169use base 'Exporter';
170 170
171BEGIN { 171BEGIN {
172 our $VERSION = '4.19'; 172 our $VERSION = 4.32;
173 173
174 our @AIO_REQ = qw(aio_sendfile aio_seek aio_read aio_write aio_open aio_close 174 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 175 aio_stat aio_lstat aio_unlink aio_rmdir aio_readdir aio_readdirx
176 aio_scandir aio_symlink aio_readlink aio_realpath aio_sync 176 aio_scandir aio_symlink aio_readlink aio_realpath aio_sync
177 aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range aio_allocate 177 aio_fsync aio_syncfs aio_fdatasync aio_sync_file_range aio_allocate
227 aio_unlink $pathname, $callback->($status) 227 aio_unlink $pathname, $callback->($status)
228 aio_mknod $pathname, $mode, $dev, $callback->($status) 228 aio_mknod $pathname, $mode, $dev, $callback->($status)
229 aio_link $srcpath, $dstpath, $callback->($status) 229 aio_link $srcpath, $dstpath, $callback->($status)
230 aio_symlink $srcpath, $dstpath, $callback->($status) 230 aio_symlink $srcpath, $dstpath, $callback->($status)
231 aio_readlink $pathname, $callback->($link) 231 aio_readlink $pathname, $callback->($link)
232 aio_realpath $pathname, $callback->($link) 232 aio_realpath $pathname, $callback->($path)
233 aio_rename $srcpath, $dstpath, $callback->($status) 233 aio_rename $srcpath, $dstpath, $callback->($status)
234 aio_mkdir $pathname, $mode, $callback->($status) 234 aio_mkdir $pathname, $mode, $callback->($status)
235 aio_rmdir $pathname, $callback->($status) 235 aio_rmdir $pathname, $callback->($status)
236 aio_readdir $pathname, $callback->($entries) 236 aio_readdir $pathname, $callback->($entries)
237 aio_readdirx $pathname, $flags, $callback->($entries, $flags) 237 aio_readdirx $pathname, $flags, $callback->($entries, $flags)
722Works like truncate(2) or ftruncate(2). 722Works like truncate(2) or ftruncate(2).
723 723
724 724
725=item aio_allocate $fh, $mode, $offset, $len, $callback->($status) 725=item aio_allocate $fh, $mode, $offset, $len, $callback->($status)
726 726
727Allocates or freed disk space according to the C<$mode> argument. See the 727Allocates or frees disk space according to the C<$mode> argument. See the
728linux C<fallocate> docuemntation for details. 728linux C<fallocate> documentation for details.
729 729
730C<$mode> can currently be C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> 730C<$mode> is usually C<0> or C<IO::AIO::FALLOC_FL_KEEP_SIZE> to allocate
731to allocate space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE | 731space, or C<IO::AIO::FALLOC_FL_PUNCH_HOLE | IO::AIO::FALLOC_FL_KEEP_SIZE>,
732IO::AIO::FALLOC_FL_KEEP_SIZE>, to deallocate a file range. 732to deallocate a file range.
733
734IO::AIO also supports C<FALLOC_FL_COLLAPSE_RANGE>, to remove a range
735(without leaving a hole) and C<FALLOC_FL_ZERO_RANGE>, to zero a range (see
736your L<fallocate(2)> manpage).
733 737
734The file system block size used by C<fallocate> is presumably the 738The file system block size used by C<fallocate> is presumably the
735C<f_bsize> returned by C<statvfs>. 739C<f_bsize> returned by C<statvfs>.
736 740
737If C<fallocate> isn't available or cannot be emulated (currently no 741If C<fallocate> isn't available or cannot be emulated (currently no
1500 aio_stat [$etcdir, "passwd"], sub { 1504 aio_stat [$etcdir, "passwd"], sub {
1501 # yay 1505 # yay
1502 }; 1506 };
1503 }; 1507 };
1504 1508
1505That C<aio_wd> is a request and not a normal function shows that creating 1509The fact that C<aio_wd> is a request and not a normal function shows that
1506an IO::AIO::WD object is itself a potentially blocking operation, which is 1510creating an IO::AIO::WD object is itself a potentially blocking operation,
1507why it is done asynchronously. 1511which is why it is done asynchronously.
1508 1512
1509To stat the directory obtained with C<aio_wd> above, one could write 1513To stat the directory obtained with C<aio_wd> above, one could write
1510either of the following three request calls: 1514either of the following three request calls:
1511 1515
1512 aio_lstat "/etc" , sub { ... # pathname as normal string 1516 aio_lstat "/etc" , sub { ... # pathname as normal string
1555passing C<undef> as working directory component of a pathname fails the 1559passing C<undef> as working directory component of a pathname fails the
1556request with C<ENOENT>, there is often no need for error checking in the 1560request with C<ENOENT>, there is often no need for error checking in the
1557C<aio_wd> callback, as future requests using the value will fail in the 1561C<aio_wd> callback, as future requests using the value will fail in the
1558expected way. 1562expected way.
1559 1563
1560If this call isn't available because your OS lacks it or it couldn't be
1561detected, it will be emulated by calling C<fsync> instead.
1562
1563=item IO::AIO::CWD 1564=item IO::AIO::CWD
1564 1565
1565This is a compiletime constant (object) that represents the process 1566This is a compiletime constant (object) that represents the process
1566current working directory. 1567current working directory.
1567 1568
1934 1935
1935This is a very bad function to use in interactive programs because it 1936This is a very bad function to use in interactive programs because it
1936blocks, and a bad way to reduce concurrency because it is inexact: Better 1937blocks, and a bad way to reduce concurrency because it is inexact: Better
1937use an C<aio_group> together with a feed callback. 1938use an C<aio_group> together with a feed callback.
1938 1939
1939It's main use is in scripts without an event loop - when you want to stat 1940Its main use is in scripts without an event loop - when you want to stat
1940a lot of files, you can write somehting like this: 1941a lot of files, you can write somehting like this:
1941 1942
1942 IO::AIO::max_outstanding 32; 1943 IO::AIO::max_outstanding 32;
1943 1944
1944 for my $path (...) { 1945 for my $path (...) {
1984 1985
1985=back 1986=back
1986 1987
1987=head3 MISCELLANEOUS FUNCTIONS 1988=head3 MISCELLANEOUS FUNCTIONS
1988 1989
1989IO::AIO implements some functions that might be useful, but are not 1990IO::AIO implements some functions that are useful when you want to use
1990asynchronous. 1991some "Advanced I/O" function not available to in Perl, without going the
1992"Asynchronous I/O" route. Many of these have an asynchronous C<aio_*>
1993counterpart.
1991 1994
1992=over 4 1995=over 4
1993 1996
1994=item IO::AIO::sendfile $ofh, $ifh, $offset, $count 1997=item IO::AIO::sendfile $ofh, $ifh, $offset, $count
1995 1998
2113 2116
2114See the C<splice(2)> manpage for details. 2117See the C<splice(2)> manpage for details.
2115 2118
2116=item IO::AIO::tee $r_fh, $w_fh, $length, $flags 2119=item IO::AIO::tee $r_fh, $w_fh, $length, $flags
2117 2120
2118Calls the GNU/Linux C<tee(2)> syscall, see it's manpage and the 2121Calls the GNU/Linux C<tee(2)> syscall, see its manpage and the
2119description for C<IO::AIO::splice> above for details. 2122description for C<IO::AIO::splice> above for details.
2120 2123
2121=item $actual_size = IO::AIO::pipesize $r_fh[, $new_size] 2124=item $actual_size = IO::AIO::pipesize $r_fh[, $new_size]
2122 2125
2123Attempts to query or change the pipe buffer size. Obviously works only 2126Attempts to query or change the pipe buffer size. Obviously works only
2124on pipes, and currently works only on GNU/Linux systems, and fails with 2127on pipes, and currently works only on GNU/Linux systems, and fails with
2125C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer 2128C<-1>/C<ENOSYS> everywhere else. If anybody knows how to influence pipe buffer
2126size on other systems, drop me a note. 2129size on other systems, drop me a note.
2130
2131=item ($rfh, $wfh) = IO::AIO::pipe2 [$flags]
2132
2133This is a direct interface to the Linux L<pipe2(2)> system call. If
2134C<$flags> is missing or C<0>, then this should be the same as a call to
2135perl's built-in C<pipe> function and create a new pipe, and should work
2136everywhere.
2137
2138If C<$flags> is non-zero, it tries to invoke the pipe2 system call with
2139the given flags (Linux 2.6.27, glibc 2.9).
2140
2141On success, the read and write file handles are returned.
2142
2143On error, nothing will be returned. If the pipe2 syscall is missing and
2144C<$flags> is non-zero, fails with C<ENOSYS>.
2145
2146Please refer to L<pipe2(2)> for more info on the C<$flags>, but at the
2147time of this writing, C<IO::AIO::O_CLOEXEC>, C<IO::AIO::O_NONBLOCK> and
2148C<IO::AIO::O_DIRECT> (Linux 3.4, for packet-based pipes) were supported.
2127 2149
2128=back 2150=back
2129 2151
2130=cut 2152=cut
2131 2153

Diff Legend

Removed lines
+ Added lines
< Changed lines
> Changed lines