Question

___ operator is used for selecting current line number.

(a) $0

(b) $1

(c) $.

(d) $_

This question was addressed to me in a job interview.

I'd like to ask this question from perl topic in section Awk – An Advanced Filter & Perl – The Master Manipulator of Unix

Answer 1

Correct option is (c) $.

Explanation: perl stores the current line number in a special variable $. ($ followed by a dot). We can use it to represent a line address and select lines from anywhere: