Function in3_sys::hex_to_bytes

pub unsafe extern "C" fn hex_to_bytes(
    hexdata: *const c_char, 
    hexlen: c_int, 
    out: *mut u8, 
    outlen: c_int
) -> c_int

convert a c hex string to a byte array storing it into an existing buffer.

@param hexdata: the hex string @param hexlen: the len of the string to read. -1 will use strlen to determine the length. @param out: the byte buffer @param outlen: the length of the buffer to write into @retval the number of bytes written