memcpy in rust

rust_memcpy.rs

fn memcpy(src: &[u8], dst: &mut [u8], len: usize) {
    let i: usize = 0;

    while i < len {
        dst[i] = src[i];
    }
}

fn main() {
    let buf: [u8; 10] = [1; 10];
    let mut dst: [u8; 20] = [2; 20];

    memcpy(&buf, &mut dst, 10);
    for i in dst {
        println!("{}", i);
    }
}