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#[cfg(test)]
mod test {

    use std::slice::from_raw_parts;
    use std::mem::size_of;

    //use super::BigU32;

    #[repr(C)]
    struct Buffer {
        i1: u16,
        i2: u16,
    }

    // doing basic test of big integration conversion and so forth
    #[test]
    fn test_zero_copy() {
        let b = Buffer {
            i1: (10u16).to_be(),
            i2: 11,
        };

        let p: *const Buffer = &b;
        let p: *const u8 = p as *const u8;
        let bytes = unsafe { from_raw_parts(p, size_of::<Buffer>()) };

        println!("{:X}{:X}{:X}{:X}", bytes[0], bytes[1], bytes[2], bytes[3]);

        // should print out as 0AB0

        let z: *const Buffer = p as *const Buffer;
        let k: &Buffer = unsafe { &*z };
        assert_eq!(k.i2, 11);
        assert_eq!(k.i1.to_be(), 10);
    }
}