This method is called in response to all stat() related functions.
$flags can hold one or more of the following values OR'd together:
STREAM_URL_STAT_LINK
For resources with the ability to link to other resource (such as an
HTTP Location: forward, or a filesystem symlink). This flag specified
that only information about the link itself should be returned, not
the resource pointed to by the link. This flag is set in response to
calls to lstat(), is_link(), or filetype().
STREAM_URL_STAT_QUIET
If this flag is set, your wrapper should not raise any errors. If
this flag is not set, you are responsible for reporting errors using
the trigger_error() function during stating of the path.
Note: The stat() call is silenced through the shut-up operator because this method would issue a warning if the
file does not exist - but file_exists() will call pathStat() in order to check exactly that. So without
the "@" operator it wouldn't be possible to run file_exists() on a resource without issuing a warning and
the resulting exception.