In almost examples in the gazebo repository, a new gazebo server is initiated by the standalone code by loading a world file. How to connect to an existing gazebo server on localhost from a standalone cpp code? This is my code for creating a joint between two models

#include <sdf/sdf.hh>
#include "gazebo/gazebo.hh"
#include "gazebo/common/Plugin.hh"
#include "gazebo/msgs/msgs.hh"
#include "gazebo/transport/transport.hh"

#include <gazebo/gazebo.hh>
#include <gazebo/common/common.hh>
#include <gazebo/physics/physics.hh>

/// \example examples/plugins/world_edit.cc
/// This example creates a WorldPlugin, initializes the Transport system by
/// creating a new Node, and publishes messages to alter gravity.
int main(int _argc, char **_argv)
{
    gazebo::physics::WorldPtr world = gazebo::physics::get_world("default");
    gazebo::physics::ModelPtr package = world->GetModel("my_package");
    gazebo::physics::LinkPtr package_link = package->GetLink("simple_box");
    gazebo::physics::ModelPtr maru = world->GetModel("maru");
    gazebo::physics::LinkPtr gripper_rot_link = maru->GetLink("gripper_rot");
    gazebo::physics::JointPtr newJoint;
    newJoint = world->GetPhysicsEngine()->CreateJoint("fixed", maru);
    newJoint->SetName("package_joint");
    newJoint->SetModel(maru);
    newJoint->Load(package_link, gripper_rot_link, gripper_rot_link->GetWorldPose());
    newJoint->Attach(package_link, gripper_rot_link);
    newJoint->SetAxis(0,  gazebo::math::Vector3(0.0f,0.0f,1.0f) );
    if( maru->GetJoint("package_joint") == NULL )
        std::cout<<"Model GetJoint : FALSE \n"<<std::endl;
    else
        std::cout<<"Model GetJoint : OK \n"<<std::endl;
    return 0;
}

i get the following error even though I launched Gazebo with

"roslaunch gazebo_ros empty_world.launch" 

where the world's name is default.

Error [PhysicsIface.cc:75] Unable to find world by name in physics::getworld[default] Exception [PhysicsIface.cc:77] Unable to find world by name in physics::getworld(world_name)

After digging into the source code I found out that the only function that can be used to connect to Gazebo is "gazebo::setupServer". This function doesn't have a parameter for choosing to either create a new master or connect to an existing one. It always create a new master

  g_master = new gazebo::Master();

Does it mean that it is impossible for the moment to connect to a running Gazebo master from cpp?