Type the bash builtin that, with no options or arguments, prints every shell variable and function of the current shell, including those that have never been exported, and that is also the builtin used with -o and +o to control shell options.
LPIC-1 Exam 102-500, objective 105. Shells and shell scripting easy
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Answer
Type the answer.
Accepted answer
set
Case sensitive — Linux is, and grading LS as ls would teach a falsehood.
Why
set with no arguments prints the names and values of all shell variables and functions in a form that can be reused as input. Given arguments it does something quite different: it sets shell options with -o and +o and replaces the positional parameters with any remaining words, which is what makes it the one builtin that does both jobs. declare and typeset print a comparable listing, but neither takes -o. The narrower view of only the exported variables comes from env or printenv, and comparing the two outputs is the quickest way to see whether a variable has been exported.
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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