How to append a string at end of a specific line in a file in bash [duplicate]

Answer 1

I would go with awk, since you can use strings and do not have to use regex, where dots would need to be escaped and anchors and/or word boundaries would need to be used. Also you can make sure the string matches a value in column 1.

awk '$1==s{$0=$0 OFS alias}1' s=192.168.1.2 alias=myalias file

Also when it is part of a larger script, it is nice to be able to use variable strings. With sed you would need shell variables and quote trickery..