Question

Note:

• Bash 3.00

How to substitute this example string 123456789, to look like 123-456-789

#!/bin/sh
# trivial example
read number;
# monotically substitute '-' into string after first three and dix digits 

Answer 1

Without the use of sed:

$ number=123456789
$ number=${number:0:3}-${number:3:3}-${number:6:3}
$ echo $number
123-456-789