I DONT GET IT

whatiswrongwiththis.php

function send_json_to_node($args) {
        $data_string=json_encode($args['postdata']);
        $ch = curl_init($args['url']);
        curl_setopt($ch, CURLOPT_CUSTOMREQUEST,"POST");
        curl_setopt($ch,CURLOPT_POSTFIELDS,$data_string);                                                          
        curl_setopt($ch,CURLOPT_RETURNTRANSFER,true);                                                              
        curl_setopt($ch,CURLOPT_HTTPHEADER,array(
        'Content-Type:application/json','Content-Length:'strlen($data_string)));
        $result = curl_exec($ch);
    }