| 1405 | BufferedWriter.__init__(self, raw, buffer_size) |
| 1406 | |
| 1407 | def seek(self, pos, whence=0): |
| 1408 | if whence not in valid_seek_flags: |
| 1409 | raise ValueError("invalid whence value") |
| 1410 | self.flush() |
| 1411 | if self._read_buf: |
| 1412 | # Undo read ahead. |
| 1413 | with self._read_lock: |
| 1414 | self.raw.seek(self._read_pos - len(self._read_buf), 1) |
| 1415 | # First do the raw seek, then empty the read buffer, so that |
| 1416 | # if the raw seek fails, we don't lose buffered data forever. |
| 1417 | pos = self.raw.seek(pos, whence) |
| 1418 | with self._read_lock: |
| 1419 | self._reset_read_buf() |
| 1420 | if pos < 0: |
| 1421 | raise OSError("seek() returned invalid position") |
| 1422 | return pos |
| 1423 | |
| 1424 | def tell(self): |
| 1425 | if self._write_buf: |