How to get the string between two dots in bash?

Question

I have several git-Repos in such format:

product.module1.git
product.module2.git
...

Now I just want to iterate over the list to get just

module1
module2

How can I achieve this? I've already tried ls in combination with grep, but I'm not able to remove the first and last string parts.

Answer 1

If your grep supports the -P option:

$ grep -oP '(?<=[.])\w+(?=[.])' file
module1
module2

(?<=[.]) is a look behind. It matches, in this case, just after a period.

\w+ matches any number of word characters.

(?=[.]) is a look ahead. It matches, in this case, just before a period.