Question

I have a file containing many words ending in a ., most of which are abbreviations, e.g.:

• etc.
• p.s.

How can I output a list which shows all of these words, only once?

• All of the words have a space before, so this space can be used to find the beginning of the word.
• None of the words appear at the beginning of the line.
• There are no sentences in the file, so the periods are all used in this manner.

Answer 1

One of the ways to do it would be:

egrep -o '\b[^ ]+\.' < list_of_words | sort | uniq