curl_easy_setopt() and you provide the handle, the option you want to set and the argument to the option. All options take exactly one argument and you must always pass exactly three parameters to the curl_easy_setopt() calls.curl_easy_setopt() call accepts several hundred different options and the various options accept a variety of different types of arguments, it is important to read up on the specifics and provide exactly the argument type the specific option supports and expects. Passing in the wrong type can lead to unexpected side-effects or hard to understand hiccups.CURLOPT_URL as all options are prefixed with CURLOPT_ and then the descriptive name — all using uppercase letters. An example line setting the URL to get the http://example.com HTTP contents could look like:curl_easy_setopt(). If you need to be able to extract the information again that you set earlier, we encourage you to keep track of that data yourself in your application.