Returns the user ID of the owner of the file, or FALSE in case of an error. The user ID is returned in numerical format, use posix_getpwuid() to resolve it to a username.
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提示: As of PHP 5.0.0 this function can also be used with some URL wrappers. Refer to 附錄 M for a listing of which wrappers support stat() family of functionality.
See also stat()