We are using some outdated encoded script which does not to be allowed to be modified. Therefor I though of a solution to modify the input automatically by using sed. This didn't work and after digging on forums I came up with the "solution" below, however it does not work. That or the output is not modified as expected.

What am I trying to achieve?

There are two kinds of inputs (so I will need two seperate rules/scripts for it). One is with a minus between every four (4) characters and the other is adding a minus between every six (6) characters.

Example 1 input:


Needs to be formatted as:


Example 2 input:


Needs to be formatted as:


I will be needed two seperate rules based on the above, which is not an issue for me.

So what I have tried so far?

After digging around here and on other forums I found the following command to work for both cases:

For example 1:

echo "0HU1L1LQXRFF2W8146LXX5WL" | fold -w4 | paste -sd'-' -
Result: 0HU1-L1LQ-XRFF-2W81-46XX-L5WL


For example 2:

echo "C00W00M9JN0777XT06XJHFGCM7Y195" | fold -w6 | paste -sd'-' -
Result: C00W00-M9JN07-77XT06-XJHFGC-M7Y195

Also perfect!


I having a hard time to translate this into a bash script based on variables. I tried the following:

echo "Unedited:"
echo $example
echo " "
echo "Modified:"
stripped=($example | fold -w6 | paste -sd'-' -)
echo $stripped

With the above I am getting the following error: syntax error near unexpected token `|'

So I modified it by escaping the '|' like this:

echo "Unedited:"
echo $example
echo " "
echo "Modified:"
stripped=($example \| fold -w6 \| paste -sd'-' -)
echo $stripped

I am not getting any errors with the above, but it's not working as it should. Both results are the same or better said the $stripped is without the minus (-) symbols in between.

Maybe someone can be so kind to tell me what I am doing wrong here and how I can fix this?

For the record; I don't need a "combined" script which adds minus (-) symbols between both 4 and 6 chars. Just either one and I will translate it to the other obvious.

Thank you kindly in advance.


In your tests, you used echo to send the value to standard output and thence the pipe, but you left that out in your script. You also need an extra $ to make it a command substitution.

stripped=$(echo $example | fold -w6 | paste -sd'-' -)

will give the desired result.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.