Add double quotation on duplicated name

Question

I want to find duplicated name from the file like below and marked them with \"\".

file:

James Miki:123-456-7890
Wang Tai:  234-563-6879
James Miki: 123-         


        

Answer 1

awk to the rescue!

$ awk -F: 'a[$1]++ {print "\"" $1 "\"" FS $2}' file

"James Miki": 123-456-7890