(PHP 5, PHP 7, PHP 8)
streamWrapper::unlink — Delete a file
$path): boolThis method is called in response to unlink().
注意:
In order for the appropriate error message to be returned this method should not be defined if the wrapper does not support removing files.
pathThe file URL which should be deleted.
成功時返回 true， 或者在失敗時返回 false。
調用此方法失敗將給出
E_WARNING（未實現(xiàn)）。
注意:
當合法的上下文傳遞給調用函數(shù)時，屬性 streamWrapper::$context 會被改變。