CODEWITHSUNDEEP
bash
Wizard
Wizard

Reputation: 22043

Use quote after command echo

I came across a small script:

$ for i in *.sh; do echo "$i"; done
name with space.sh
name_with_dash.sh

When I unquoted $i, it produces the same result.

$ for i in *.sh; do echo $i; done
name with space.sh
name_with_dash.sh

I can see how "$i" might need to be quoted for old-fashioned commands like test [ ], cd, or rm. Is it necessary to use quotes with echo, too?

Upvotes: 1

Views: 82

Answers (1)

Barmar
Barmar

Reputation: 780724

You'll see a difference if a filename contains multiple consecutive spaces:

touch "name with   multiple spaces.sh"

With the quotes it will correctly echo:

name with   multiple spaces.sh

Without the quotes it will combine all the spaces, displaying an incorrect filename:

name with multiple spaces.sh

The quotes prevent word-splitting, which parses the result of the variable expansion as words separated by whitespace (you can change the delimiter characters by setting the IFS variable).

You'll rarely go wrong if you always quote your variables. You should only use the variable unquoted when you specifically need word splitting or wildcard expansions.

Upvotes: 5

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