Question

What is the exit status of cmp command if both the files are identical?

(a) 0

(b) 1

(c) 2

(d) undefined

I got this question in a national level competition.

I'm obligated to ask this question of Comparing Files:comm, cmp and diff Command in division Handling Ordinary Files of Unix

Answer 1

The correct answer is (a) 0

For explanation I would say: The exit status of cmp command is 0 if both the files are identical and 1 if both the files are different. The exit status is 2 if the program encounters a problem.