Let's say username is 'e5454' and password is 'gf9flge'.
Here's what I have, but I don't know how to pass the -u :, when I pass them as parameters, I get an error that the credentials were not passed.
$accessWatsonToken = curl_init($url);
$params=http_build_query(array('url' => 'https://gateway.watsonplatform.net/tone-analyzer/api/v3/tone', 'password' =>'gf9flge', 'username'=>'e5454'));
curl_setopt($accessWatsonToken, CURLOPT_URL, "https://gateway.watsonplatform.net/authorization/api/v1/token?$params");
curl_setopt($accessWatsonToken, CURLOPT_RETURNTRANSFER, 1);
$url='index.php?token='.curl_exec($accessWatsonToken);
curl_close($accessWatsonToken);
echo($url);