pub type SmsInteractRequestProc = Option<unsafe extern "C" fn(arg1: SmsConn, arg2: SmPointer, arg3: c_int)>;
enum SmsInteractRequestProc { None, Some(unsafe extern "C" fn(_: *mut _SmsConn, _: *mut c_void, _: i32)), }
No value.
Some value of type T.
T