Looping all subdierctories in multiple pipes

Hello friends,
I want to run this code on every document in every sub-directory.

tr -d '\n' < MulitpleInput.txt | awk '{gsub(/\. /,".\n");print}' | grep �\[" >> SingleOutput.txt

I tried several looping techniques but couldn't get it to run in this example. Any ideas?

Thank you

I can't tell from your code what you are trying to do.
If you are looking to change, a lot of files, the find
command works well along with sed.

You may want to show what is in the input files
and what the output files should look like.

Whatever you're up to, the tr is unnecessary and potentially problematic. Its output is not a valid text file and its length could pose a problem for some awk implementations.

You can achieve the same effect directly with awk and an empty ORS.

Regards,
Alister