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… | |
| 258 | } |
258 | } |
| 259 | }; |
259 | }; |
| 260 | |
260 | |
| 261 | aio_close $fh, $callback->($status) |
261 | aio_close $fh, $callback->($status) |
| 262 | Asynchronously close a file and call the callback with the result |
262 | Asynchronously close a file and call the callback with the result |
| 263 | code. *WARNING:* although accepted, you should not pass in a perl |
263 | code. |
| 264 | filehandle here, as perl will likely close the file descriptor |
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| 265 | another time when the filehandle is destroyed. Normally, you can |
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| 266 | safely call perls "close" or just let filehandles go out of scope. |
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| 267 | |
264 | |
| 268 | This is supposed to be a bug in the API, so that might change. It's |
265 | Unfortunately, you can't do this to perl. Perl *insists* very |
| 269 | therefore best to avoid this function. |
266 | strongly on closing the file descriptor associated with the |
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267 | filehandle itself. Here is what aio_close will try: |
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268 | |
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269 | 1. dup()licate the fd |
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270 | 2. asynchronously close() the duplicated fd |
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271 | 3. dup()licate the fd once more |
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272 | 4. let perl close() the filehandle |
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273 | 5. asynchronously close the duplicated fd |
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274 | |
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275 | The idea is that the first close() flushes stuff to disk that |
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276 | closing an fd will flush, so when perl closes the fd, nothing much |
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277 | will need to be flushed. The second async. close() will then flush |
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278 | stuff to disk that closing the last fd to the file will flush. |
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279 | |
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280 | Just FYI, SuSv3 has this to say on close: |
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281 | |
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282 | All outstanding record locks owned by the process on the file |
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283 | associated with the file descriptor shall be removed. |
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284 | |
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285 | If fildes refers to a socket, close() shall cause the socket to be |
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286 | destroyed. ... close() shall block for up to the current linger |
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287 | interval until all data is transmitted. |
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288 | [this actually sounds like a specification bug, but who knows] |
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289 | |
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290 | And at least Linux additionally actually flushes stuff on every |
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291 | close, even when the file itself is still open. |
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292 | |
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293 | Sounds enourmously inefficient and complicated? Yes... please show |
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294 | me how to nuke perl's fd out of existence... |
| 270 | |
295 | |
| 271 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
296 | aio_read $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
| 272 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
297 | aio_write $fh,$offset,$length, $data,$dataoffset, $callback->($retval) |
| 273 | Reads or writes $length bytes from the specified $fh and $offset |
298 | Reads or writes $length bytes from the specified $fh and $offset |
| 274 | into the scalar given by $data and offset $dataoffset and calls the |
299 | into the scalar given by $data and offset $dataoffset and calls the |
