Question

Which one of the following command is used for replacing | with : globally?

(a) sed  ‘s/|/:/’ emp.lst

(b) sed ‘/|/:/’ emp.lst

(c) sed  ‘s/|/:/g’ emp.lst

(d) sed ‘s/

I have been asked this question in a national level competition.

I want to ask this question from sed command topic in portion Filters using Regular Expressions of Unix

Answer 1

Right choice is (c) sed  ‘s/|/:/g’ emp.lst

Easiest explanation: sed can perform substitution i.e. it allows us to replace a pattern in its input with some other pattern. The flag g is used for performing substitution globally.