How to retrieve the first n characters of a variable in Bash?

Question

How to retrieve the first 10 characters of a variable with Bash?

FOO="qwertzuiopasdfghjklyxcvbnm"

I need to get qwertzuiop.

That isn't correct assignment syntax. `foo=${foo:0:10}` ... `foo=${foo%%"${foo##??????????}"}` — ormaaj, Feb 21 '13 at 00:44

score 126 · Answer 1 · answered Feb 21 '13 at 00:43

126

If the variable is: FOO="qwertzuiopasdfghjklyxcvbnm"

then

 echo ${FOO:0:10}

will give the first 10 characters.

answered Feb 21 '13 at 00:43

P.P

score 62 · Answer 2 · answered Feb 21 '13 at 00:47

62

Use the head command.

echo $FOO | head -c 10
=> qwertzuiop

answered Feb 21 '13 at 00:47

pje

I think this answer make the most sense, and works at the end of a long line used to generate the string `FOO`. – Bryson S. Nov 02 '19 at 17:56

2 Answers2