sed 未选择 bash 变量值

Question

I have a file named webroot with below contents:

ROOT= .
#ROOT = Current Directory for Installers. Specify in double quotes.

I want to replace value foe first occurrence of ROOT with the path in double quotes, for which I created below script

#!/bin/bash

ppath="$(dirname $(pwd))"

sed -i '0,/^ROOT.*/s/^ROOT.*/ROOT = \"\${ppath}\"/' webroot

grep -m1 ROOT webroot 

However, when I execute the script, I see below as output:

ROOT = "${ppath}"

Updated the script to below, however same result:

#!/bin/bash

ppath="$(dirname $(pwd))"

sed -i "0,/^ROOT.*/s/^ROOT.*/ROOT = \"\${ppath}\"/" webroot

grep -m1 ROOT webroot 

Any suggestions, how this can be fixed?

Answer 1

Used below:

sed -i "0,/^ROOT.*/s|^ROOT.*|ROOT = \"${ppath}"|" webroot