When Sun Microsystems ported Berkeley Unix from the Digital VAX to the Motorola 680x0 in the early 1980s,many C programs stopped working, and had to be repaired. In effect, the 680x0 revealed certain classes of program bugs that one could “get away with” on the VAX. One of these classes of bugs occurred in programs that use more than one size of integer (e.g., short and long), and arose from the fact that the VAX is a little-endian machine, while the 680x0 is big-endian (Section C 5.2). Another class of bugs occurred in programs that manipulate both null and empty strings. It arose from the fact that location zero in a Unix process’s address space on the VAX always contained a zero, while the same location on the 680x0 is not in the address space, and will generate a protection error if used. For both of these classes of bugs, give examples of program fragments that would work on a VAX but not on a 680x0.