drupal_realpath
function drupal_realpath
drupal_realpath($uri)
Resolves the absolute filepath of a local URI or filepath.
The use of drupal_realpath() is discouraged, because it does not work for remote URIs. Except in rare cases, URIs should not be manually resolved.
Only use this function if you know that the stream wrapper in the URI uses the local file system, and you need to pass an absolute path to a function that is incompatible with stream URIs.
Parameters
string $uri: A stream wrapper URI or a filepath, possibly including one or more symbolic links.
Return value
string|false The absolute local filepath (with no symbolic links), or FALSE on failure.