bash escape ~ tilde

Question

Does tilde character need to be escaped in bash script?

I have tried to escape it with \~ but it does not help. If I remove the ~ character, the code below works as expected.

            if ! [[ "$line" =~ ^[0-9a-zA-Z-~]+$ ]]; then
                    echo "skipping .. $line"
                    continue
            fi

How do I add the tilde character in the above expression?

score 8 · Accepted Answer · edited May 23 '17 at 12:11

8

Don't put ~ after -. Change the regexp to:

if ! [[ "$line" =~ ^[0-9a-zA-Z~-]+$ ]]; then

and you'll be fine.

Take a look to this post for more explanations why hyphen may be the last element of the class.

edited May 23 '17 at 12:11

Community

answered Mar 25 '13 at 22:44

Bash is just confused because `-` is used to specify ranges in `[]`, except when it's first or last. – that other guy Mar 25 '13 at 23:30
1

That's not only `bash`, see the link added in the post – Gilles Quénot Mar 25 '13 at 23:30
It does make sense now. Thanks for the link – surajz Mar 26 '13 at 02:03

1 Answers1