Description:
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DIR functions (scandir, is_dir, etc.) do not recognize root UNC shares as valid directories, but work on subdirectories of the share. This problem surfaced after upgrading from 5.2.0 to 5.2.1 and is present in the latest snap (php5.2-win32-200702201130.zip).

Reproduce code:
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If the share is //fs/misc,

opendir("//fs/misc");

reports:

Warning: scandir(//fs/misc) [function.scandir]: failed to open dir: No error in myscript.php on line 2

But opening a subdirectory like opendir("//fs/misc/docs"); works without error.


Expected result:
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No error.

Actual result:
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Warning: scandir(//fs/misc) [function.scandir]: failed to open dir: No error in myscript.php on line 2