en to <b>*ex</b> reusing or allocating a new extension if necessary so <b>*ex</b> should either be <b>NULL</b> or a valid <b>X509_EXTENSION</b> structure it must <b>not</b> be an uninitialised pointer.</p>

<p>X509_EXTENSION_create_by_OBJ() is identical to X509_EXTENSION_create_by_NID() except it creates and extension using <b>obj</b> instead of a NID.</p>

<p>X509_EXTENSION_get_object() returns the extension type of <b>ex</b> as an <b>ASN1_OBJECT</b> pointer. The returned pointer is an internal value which