pub unsafe extern "C" fn gst_sdp_message_add_attribute(
msg: *mut GstSDPMessage,
key: *const c_char,
value: *const c_char,
) -> GstSDPResult
pub unsafe extern "C" fn gst_sdp_message_add_attribute(
msg: *mut GstSDPMessage,
key: *const c_char,
value: *const c_char,
) -> GstSDPResult