For Loops in Bash

By Thomas Taylor | | 2 minutes
Bash

Using a for loop in Bash is simple!

for loop over strings

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for i in "follow" "the" "white" "rabbit"; do
    echo "${i}"
done

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follow
the
white
rabbit

for loop with range

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for i in {0..2}; do
    echo "${i}"
done

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bash 4 added an increment parameter for ranges

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for i in {0..6..2}; do
    echo "${i}"
done

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for loop with array

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a=("fried" "green" "tomatoes")
for i in ${a[@]}; do
    echo "${i}"
done

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fried
green
tomatoes

for loop C-style

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for (( i = 0; i <= 3; i++ )); do
    echo "${i}"
done

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for loop control statements: break & continue

break statement

The break statement terminates the current loop.

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for i in "first" "second" "break" "third"; do
    if [[ "${i}" == "break" ]]; then
        break
    fi
    echo "${i}"
done

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first
second

continue statement

The continue statement skips the current iteration and ‘continues’ to the next iteration.

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for i in "first" "second" "break" "third"; do
    if [[ "${i}" == "break" ]]; then
        continue
    fi
    echo "${i}"
done

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first
second
third