Type the complete sed command that prints only the fifth line of data.txt and nothing else, using the option that suppresses sed's automatic printing together with an explicit print command.
LPIC-1 Exam 101-500, objective 103. GNU and Unix commands medium
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.
Answer
Type the answer.
Accepted answers
sed -n '5p' data.txtsed -n 5p data.txtsed -n "5p" data.txtsed --quiet '5p' data.txtsed -n '5 p' data.txtsed --silent '5p' data.txtsed -n -e '5p' data.txtsed -ne '5p' data.txtsed --quiet 5p data.txt
Case sensitive — Linux is, and grading LS as ls would teach a falsehood.
Why
sed normally prints every line of the pattern space after running the script, so a print command on top of that would duplicate lines. -n (also --quiet or --silent) turns the automatic output off and leaves p as the only thing that emits anything. A bare number is a line-number address; the other address forms are /regex/, $ for the last line, first~step for every step-th line and addr1,addr2 for a range.
Where this comes from
- Cited
- manual page sed(1)
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.
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