| … | |
… | |
| 152 | print "read $_[0] bytes: <$buffer>\n"; |
152 | print "read $_[0] bytes: <$buffer>\n"; |
| 153 | }; |
153 | }; |
| 154 | |
154 | |
| 155 | =item aio_readahead $fh,$offset,$length, $callback |
155 | =item aio_readahead $fh,$offset,$length, $callback |
| 156 | |
156 | |
| 157 | Asynchronously reads the specified byte range into the page cache, using |
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| 158 | the C<readahead> syscall. If that syscall doesn't exist (likely if your OS |
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| 159 | isn't Linux) the status will be C<-1> and C<$!> is set to C<ENOSYS>. |
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| 160 | |
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| 161 | C<aio_readahead> populates the page cache with data from a file so that |
157 | C<aio_readahead> populates the page cache with data from a file so that |
| 162 | subsequent reads from that file will not block on disk I/O. The C<$offset> |
158 | subsequent reads from that file will not block on disk I/O. The C<$offset> |
| 163 | argument specifies the starting point from which data is to be read and |
159 | argument specifies the starting point from which data is to be read and |
| 164 | C<$length> specifies the number of bytes to be read. I/O is performed in |
160 | C<$length> specifies the number of bytes to be read. I/O is performed in |
| 165 | whole pages, so that offset is effectively rounded down to a page boundary |
161 | whole pages, so that offset is effectively rounded down to a page boundary |
| 166 | and bytes are read up to the next page boundary greater than or equal to |
162 | and bytes are read up to the next page boundary greater than or equal to |
| 167 | (off-set+length). C<aio_readahead> does not read beyond the end of the |
163 | (off-set+length). C<aio_readahead> does not read beyond the end of the |
| 168 | file. The current file offset of the file is left unchanged. |
164 | file. The current file offset of the file is left unchanged. |
| 169 | |
165 | |
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166 | If that syscall doesn't exist (likely if your OS isn't Linux) it will be |
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167 | emulated by simply reading the data, which would have a similar effect. |
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168 | |
| 170 | =item aio_stat $fh_or_path, $callback |
169 | =item aio_stat $fh_or_path, $callback |
| 171 | |
170 | |
| 172 | =item aio_lstat $fh, $callback |
171 | =item aio_lstat $fh, $callback |
| 173 | |
172 | |
| 174 | Works like perl's C<stat> or C<lstat> in void context. The callback will |
173 | Works like perl's C<stat> or C<lstat> in void context. The callback will |
| … | |
… | |
| 200 | with the fsync result code. |
199 | with the fsync result code. |
| 201 | |
200 | |
| 202 | =item aio_fdatasync $fh, $callback |
201 | =item aio_fdatasync $fh, $callback |
| 203 | |
202 | |
| 204 | Asynchronously call fdatasync on the given filehandle and call the |
203 | Asynchronously call fdatasync on the given filehandle and call the |
| 205 | callback with the fdatasync result code. Might set C<$!> to C<ENOSYS> if |
204 | callback with the fdatasync result code. |
| 206 | C<fdatasync> is not available. |
205 | |
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206 | If this call isn't available because your OS lacks it or it couldn't be |
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207 | detected, it will be emulated by calling C<fsync> instead. |
| 207 | |
208 | |
| 208 | =back |
209 | =back |
| 209 | |
210 | |
| 210 | =head2 SUPPORT FUNCTIONS |
211 | =head2 SUPPORT FUNCTIONS |
| 211 | |
212 | |
| … | |
… | |
| 316 | return undef if $_[0] < 0; |
317 | return undef if $_[0] < 0; |
| 317 | |
318 | |
| 318 | # try to generate nice filehandles |
319 | # try to generate nice filehandles |
| 319 | my $sym = "IO::AIO::fd#$_[0]"; |
320 | my $sym = "IO::AIO::fd#$_[0]"; |
| 320 | local *$sym; |
321 | local *$sym; |
| 321 | open *$sym, "+<&=$_[0]" |
322 | |
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323 | open *$sym, "+<&$_[0]" # usually under any unix |
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324 | or open *$sym, "<&$_[0]" # cygwin needs this |
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325 | or open *$sym, ">&$_[0]" # cygwin needs this |
| 322 | or return undef; |
326 | or return undef; |
| 323 | |
327 | |
| 324 | *$sym |
328 | *$sym |
| 325 | } |
329 | } |
| 326 | |
330 | |
