How to specify endian?

[goldwind-ting]

Continuing the discussion from How best to convert `&[u8]` to `&[u16]`:

@alice

fn to_u8_slice(slice: &mut [u16]) -> &mut [u8] {
    let byte_len = 2*slice.len();
    unsafe {
        std::slice::from_raw_parts_mut(
            slice.as_mut_ptr().cast::<u8>(),
            byte_len
        )
    }
}

How to specify endian with this method?

[RedDocMD]

@goldwind-ting

How to specify endian with this method?

You cannot, it will take the native endianess.

[H2CO3]

To be clear, you can't change the endianness if you want to re-use the memory as-is (i.e., borrow). That should be obvious. The data is laid out in memory as it is laid out however your system treats multi-byte types, i.e., native endianness.

If you want to convert between representations of different endianness, then you'll have to copy the values in order to rearrange bytes. Example.

[goldwind-ting]

Cool!