src/RpkUtils/Sysinfo/Server.php
public static function hostname()
    {
        if($os = static::os(true)){
            $os = explode(' ', $os);
             if('/' == DIRECTORY_SEPARATOR ){
                $hostname = $os[1];
            }else{
                $hostname = $os[2];
            }
        }else{
            $hostname = '';
        }
        
        return $hostname;
    }
public static function hostname()
    {
        if($os = static::os(true)){
            $os = explode(' ', $os);
             if('/' == DIRECTORY_SEPARATOR ){
                $hostname = $os[1];
            }else{
                $hostname = $os[2];
            }
        }else{
            $hostname = '';
        }
        
        return $hostname;
    }
Server hostname
@return string