Cloudflare API v4 Dynamic DNS Update in Bash, without unnecessary requests
bash <(curl -fsSL git.io/cf-ddns.sh) \
-k cloudflare-api-key \
-u user@example.com \
-z example.com \
-h host.example.com \
-t A|AAAA \
-p true \
-o 1.2.3.4 \
-f false