Interview Q&A / Linux & Shell

INTERVIEW Q&A · 63 QUESTIONS

Linux & Shell interview questions

Permissions, processes, pipes and the commands you are expected to know cold.

  1. When do you need grep -E, and what is the difference from basic grep patterns?

    Basic grep treats +, ?, | and () as ordinary characters unless escaped. grep -E (extended regex) gives them their regex meaning, so grep -E 'cat|dog' matches either word. Use -F when you want a plain fixed string with no regex at all.

    IntermediateQuick answer1 min read