Description:
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When using open_basedir as a prefix, attempting to access files or directories which match the prefix but are not present on the filesystem raise open_basedir restriction warnings.



Reproduce code:
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// create files or directories on the file system "/foo1", "/foo2"
// add "/foo" (not "/foo/") to the open basedir restriction, then:

var_dump(file_exists('/foo1'));
var_dump(file_exists('/foo2'));
var_dump(file_exists('/foo3'));



Expected result:
----------------
this is the output returned:
bool(true)
bool(true)
bool(false)

which is expected, however, the "false" returned by the third call is disingenuous... it is false because the call is being blocked by open_basedir, and the following warning is triggered:

[Fri May  2 17:33:05 2008] [error] PHP Warning:  file_exists(): open_basedir restriction in effect. File(/foo3) is not within the allowed path(s)