Function SQLDescribeCol 

pub unsafe fn SQLDescribeCol(
    statementhandle: *mut c_void,
    columnnumber: u16,
    columnname: Option<&mut [u8]>,
    namelength: Option<*mut i16>,
    datatype: Option<*mut i16>,
    columnsize: Option<*mut u64>,
    decimaldigits: Option<*mut i16>,
    nullable: Option<*mut i16>,
) -> i16