[macote]

This is how I use it in my bash script:

  current_ip=$(curl -s -X GET https://1.1.1.1/cdn-cgi/trace | grep -Po "(?<=ip=)(.*)")

[networked]

I find awk more clear for this kind of job. You can replace

  grep -Po "(?<=ip=)(.*)"

with

  awk -F= '$1 == "ip" { print $2 }'

[macote]

Thanks for that, I agree.