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XK0-006 Automation, Orchestration, and Scripting Practice Question

A Linux administrator is writing a bash script to process a list of usernames stored in an array. The script must iterate over each username and print a welcome message. Which TWO of the following loops will correctly iterate over the array 'users' and print 'Welcome, <username>'? (Choose TWO.)

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

for ((i=0; i<${#users[@]}; i++)); do echo "Welcome, ${users[$i]}"; done

Arrays can be iterated using for with ${users[@]} or using indices. The correct methods are direct iteration over elements and using a C-style for loop with indices.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✗
for user in $users; do echo "Welcome, $user"; done
Why it's wrong here
$users expands only to the first element of the array.
✗
for user in "${users[*]}"; do echo "Welcome, $user"; done
Why it's wrong here
${users[*]} expands to a single string with all elements joined by IFS, so the loop runs only once.
✗
while read user; do echo "Welcome, $user"; done < <(printf '%s\n' "${users[@]}")
Why it's wrong here
This is unnecessarily complex and not a simple loop for array iteration; it uses process substitution.
✓
for ((i=0; i<${#users[@]}; i++)); do echo "Welcome, ${users[$i]}"; done
Why this is correct
Correct. Uses C-style for loop with array length and indexing.
✓
for user in ${users[@]}; do echo "Welcome, $user"; done
Why this is correct
Correct. ${users[@]} expands to all elements.

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XK0-006 Automation, Orchestration, and Scripting Practice Question

Why each option matters

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