Find and replace in shell scripting

Question

Is it possible to search in a file using shell and then replace a value? When I install a service I would like to be able to search out a variable in a config file and then repl

Answer 1

You can use sed to perform search/replace. I usually do this from a bash shell script, and move the original file containing values to be substituted to a new name, and run sed writing the output to my original file name like this:

#!/bin/bash
mv myfile.txt myfile.txt.in

sed -e 's/PatternToBeReplaced/Replacement/g' myfile.txt.in > myfile.txt.

If you don't specify an output, the replacement will go to stdout.