You open a file with vi. You immediately type `dd`. What have you done, and what mode were you in?

LPIC-1 Exam 101-500, objective 103. GNU and Unix commands easy

Machine-checked — no person has signed for it. This question was read against the source cited below by an automated pass, which found no contradiction. That is a weaker claim than it sounds: the same kind of process wrote the question, so it can confirm its own mistake.

Treat it as a good draft rather than as settled fact, and read the source below before you rely on it. It is not used in mock exams here — only questions a person has signed for are.

How these questions are written — where each question comes from, what the verification ledger records, and what happens when one is found wrong.

The options

Not correct You were in command mode and deleted the character under the cursor twice.

Wrong. That is what pressing x twice does. dd operates on the entire line.

Not correct You were in insert mode and typed the characters 'dd' into the file.

Wrong. vi opens in command mode, not insert mode. You reach insert mode only after pressing i, a, o or a similar key.

Correct You were in command (normal) mode and deleted the current line into the buffer.

Correct. vi starts in command mode, and dd cuts the whole current line, which p can then paste elsewhere.

Not correct You were in command mode and duplicated the current line.

Wrong. Duplicating a line is yy followed by p. dd removes the line rather than copying it.

Why

vi opens in command mode, which is why typing text at first appears to do strange things. In command mode dd cuts a line, yy yanks (copies) one, and p puts the buffer back after the cursor line. Prefix with a count for more lines: 3dd cuts three.

Where this comes from

Cited
LPI exam objective 103.8
What it says
Navigate vi modes and use basic editing commands.

Practise this

Reading one question is not practice. The trainer will draw a short set from objective 103 and space the ones you get wrong.

Practise LPIC-1 Exam 101-500

More questions on this objective

All questions on GNU and Unix commands

Practise LPIC-1 Exam 101-500