How to pass data in header while using CURL? code example

Example 1: curl pass a header

curl -H "Accept-Charset: utf-8" -H "Content-Type: application/x-www-form-urlencoded" http://www.some-domain.com

Example 2: curl pass data in request

curl -d "param1=value1¶m2=value2" -X POST http://localhost:3000/data