Type the bash builtin command, with its argument, that reads one line from standard input and stores it in the shell variable named ANSWER.
LPIC-1 Exam 102-500, objective 105. Shells and shell scripting 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
read ANSWERread -r ANSWER
Case sensitive — Linux is, and grading LS as ls would teach a falsehood.
Why
`read ANSWER` consumes one line from standard input, strips the trailing newline and assigns the result to ANSWER, without a dollar sign on the variable name. Useful options: -p to print a prompt first, -r to stop backslashes being treated as escapes (recommended, and what shellcheck advises), -s to hide typing for passwords, and -t for a timeout. With several names, the line is split on IFS and the last name receives everything that remains. read returns a non-zero exit status at end of file, which is what makes `while read -r line; do ... done < file` terminate.
Where this comes from
- Cited
- LPI exam objective 105.2
- What it says
- Read user input inside a shell script.
Practise this
Reading one question is not practice. The trainer will draw a short set from objective 105 and space the ones you get wrong.
More questions on this objective
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