(PECL OAuth >= 0.99.1)
OAuth::getRequestToken — Fetch a request token
$request_token_url
   [, string $callback_url
   [, string $http_method
  ]] )Fetch a request token, secret and any additional response parameters from the service provider.
request_token_urlURL to the request token API.
callback_url
       OAuth callback URL. If callback_url is passed and is an empty value, it is set to "oob" to address the OAuth 2009.1 advisory.
      
http_methodHTTP method to use, e.g. GET or POST.
   Returns an array containing the parsed OAuth response on success or FALSE on failure.
  
| Version | Description | 
|---|---|
| 1.0.0 | Previously returned NULLon failure, instead ofFALSE. | 
| 0.99.9 | The callback_urlparameter was added | 
Example #1 OAuth::getRequestToken() example
<?php
try {
    $oauth = new OAuth(OAUTH_CONSUMER_KEY,OAUTH_CONSUMER_SECRET);
    $request_token_info = $oauth->getRequestToken("https://example.com/oauth/request_token");
    if(!empty($request_token_info)) {
        print_r($request_token_info);
    } else {
        print "Failed fetching request token, response was: " . $oauth->getLastResponse();
    }
} catch(OAuthException $E) {
    echo "Response: ". $E->lastResponse . "\n";
}
?>
The above example will output something similar to:
Array
(
    [oauth_token] => some_token
    [oauth_token_secret] => some_token_secret
)