curl -v https://login.salesforce.com/services/oauth2/token -d "grant_type=password&client_id=<client_id>&client_secret=<client_secret>&username=name@address.com&password=<password><security-token>" -H "Content-Type:application/x-www-form-urlencoded"

var task = auth.UsernamePasswordAsync(
    <client_id>,
    <client_secret>,
    name@address.com,
    <password><security_token>,
    https://login.salesforce.com/services/oauth2/token);

task.Wait();