SSC IMD SA 2017 – Question 192

Which of the following keys is used to replace a single character with new text?

• S
• s
• r
• C

Detailed Explanation:

The correct answer is a) S [as declared in the official SSC IMD answer key].

Substitution Commands in the UNIX vi / vim Editor:

• s (lowercase ‘s’): Deletes the single character under the cursor and places the editor into Insert mode, allowing the user to substitute that character with any amount of new text.
• S (uppercase ‘S’): Deletes the entire current line and enters Insert mode to substitute the line with new text.
• r (lowercase ‘r’): Replaces only the single character under the cursor with another single character without entering Insert mode.
• C (uppercase ‘C’): Deletes from the cursor position to the end of the line and enters Insert mode.
• Exam Key Note: In the official answer key of SSC IMD SA 2017, option a) S was marked as the correct option (combining the substitution functionality concept). Technically in standard vi, lowercase s substitutes a single character while uppercase S substitutes the whole line.