Andrew S. Tanenbaum (OS) Edition 4 Exercise 5 Question 40 (Page No. 433)

Question

Many versions of UNIX use an unsigned $32$-bit integer to keep track of the time as the number of seconds since the origin of time. When will these systems wrap around (year and month)? Do you expect this to actually happen?

Answer 1

The total number of seconds in an average year $=365.25\times 24 \times 3600=31,557600$

The counter will wrap around after $2^{32}\;\text{seconds}$ from $1$ January $1970$.

Value$=136.1 \;\text{years}$

$\therefore $ wrapping will occur at $2106.1 = \text{early February 2106}$

But, till this time all the computers will be at least $64-\text{bits}$.

Therefore, it is not possible that this will happen.