Description:
------------
file_get_contents() supports an offset. However, at certain times this gives an "stream does not support seeking" at a certain offset. This offset might differ with installations and the website a resource is requested from.



Reproduce code:
---------------
file_get_contents("http://stock.ter.dk/taske.jpg", null, null, 8000, 1000);

Expected result:
----------------
The content should be returned

Actual result:
--------------
Warning: file_get_contents(): stream does not support seeking in Command line code on line 1

Warning: file_get_contents(): Failed to seek to position 8000 in the stream in Command line code on line 1



The exact cutoff-point seem to differ. A script such as the following gives different results at different servers.

<?php
$offset = 0;
$length = 500;
while ($file = file_get_contents("http://stock.ter.dk/taske.jpg", null, null, $offset, $length)) {
  print "$offset, $length\n";
  $offset += $length;
}
?>

PHP 5.2.6-0.dotdeb.1 with Suhosin-Patch 0.9.6.2 (cli):

0, 500
500, 500
1000, 500
1500, 500
2000, 500
2500, 500
3000, 500
3500, 500
4000, 500
4500, 500
5000, 500
5500, 500
6000, 500
6500, 500
7000, 500
7500, 500

Warning: file_get_contents(): stream does not support seeking in /home/penguin/- on line 4

Warning: file_get_contents(): Failed to seek to position 8000 in the stream in /home/penguin/- on line 4

PHP 5.2.0 (cli) (built: Nov 26 2006 10:25:07):

0, 500
500, 500
1000, 500

Warning: file_get_contents(): stream does not support seeking in /home/penguin/- on line 4

Warning: file_get_contents(): Failed to seek to position 1500 in the stream. in /home/penguin/- on line 4



The behaviour is the same whether php-cli or mod_php is used, as seen at http://stock.ter.dk/filegetbug.php


(as a side note, file_get_contents() [or rather, the http stream] could try to use a ranged request when an offset and range is present, with a fallback to the current behaviour if the webserver returns the whole file)