JAVASCRIPT

1line uuid

// using Date
new Date().getTime().toString().substring(9,13)

// using Random
Math.ceil(Math.random()*100)
// Note: add more 0s in 100 if you want to make it even more unique.

1 line uuid

awk '("uuidgen" | getline uuid) > 0 {print uuid, $0} {close("uuidgen")}' myfile.csv