Description:
------------
According to the manual, "readdir" Returns the filename of the next file from the directory. The filenames are returned in the order in which they are stored by the filesystem.

Under ZFS filesystem, return is not done in the right way.

tests are done under debian x86 with one zfs filer (sunOS) and one linux filer (debizn x86).

Reproduce code:
---------------
# mkdir temp
# cd temp/
# for i in `seq 0 19`; do touch $i.txt; done

<?php
$dir = opendir("temp");
while (false !== ($file = readdir($dir))) {
        echo "$file\n";
        }
?>

Expected result:
----------------
.
..
0.txt
1.txt
2.txt
3.txt
4.txt
5.txt
6.txt
7.txt
8.txt
9.txt
10.txt
11.txt
12.txt
13.txt
14.txt
15.txt
16.txt
17.txt
18.txt
19.txt

Actual result:
--------------
.
..
0.txt
7.txt
9.txt
12.txt
15.txt
14.txt
8.txt
13.txt
6.txt
1.txt
10.txt
17.txt
19.txt
2.txt
5.txt
4.txt
18.txt
3.txt
16.txt
11.txt