sed - Add text at the end of each line

Question

I'm on Linux command line and I have file with

127.0.0.1
128.0.0.0
121.121.33.111

I want

127.0.0.1:80
128.0.0.0:80
121.121.33.111:80

I remember my colleagues were using sed for that, but after reading sed manual still not clear how to do it on command line?

Answer 1

You could try using something like:

sed -n 's/$/:80/' ips.txt > new-ips.txt

Provided that your file format is just as you have described in your question.

The s/// substitution command matches (finds) the end of each line in your file (using the $ character) and then appends (replaces) the :80 to the end of each line. The ips.txt file is your input file... and new-ips.txt is your newly-created file (the final result of your changes.)

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Also, if you have a list of IP numbers that happen to have port numbers attached already, (as noted by Vlad and as given by aragaer,) you could try using something like:

sed '/:[0-9]*$/ ! s/$/:80/' ips.txt > new-ips.txt

So, for example, if your input file looked something like this (note the :80):

127.0.0.1
128.0.0.0:80
121.121.33.111

The final result would look something like this:

127.0.0.1:80
128.0.0.0:80
121.121.33.111:80