Considering the following C function:
int sum(int x, int y) {
return x + y;
}When compiled on our sample machines. we generate machine code having the following byte representations:
- Linux 32:
55 89 e5 8b 45 0c 03 45 08 c9 c3 - Windows:
55 89 e5 8b 45 0c 03 45 08 5d c3 - Sun:
81 c3 e0 08 90 02 00 09 - Linux 64:
55 48 89 e5 89 7d fc 89 75 f8 03 45 fc c9 c3
Hence we find that the instruction codings are different. Different machine types use different instructions and encodings, so binary code is seldom portable across different combinations of machine and operating system.