Type the name of the shell variable, without a leading dollar sign, whose value bash expands and displays as the primary prompt string before each interactive command.
LPIC-1 Exam 102-500, objective 105. Shells and shell scripting easy
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Answer
Type the answer.
Accepted answer
PS1
Case sensitive — Linux is, and grading LS as ls would teach a falsehood.
Why
PS1 holds the primary prompt, and bash expands its backslash escapes afresh every time it prompts: \u is the user name, \h the short hostname, \w the working directory and \$ prints # for root and $ for everyone else. The companion variables are PS2, the continuation prompt shown when a quote or a pipeline is unfinished and whose default is >, PS3, the prompt used by select, and PS4, the prefix printed by an execution trace under set -x. A prompt is a per-shell setting rather than something children inherit, so it belongs in ~/.bashrc, or in /etc/bash.bashrc when it is meant for everyone, not in ~/.bash_profile alone.
Where this comes from
- Cited
- manual page bash(1)
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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