Minimum sensor polling demo for linux with sdl2 and c-api

Hi I am using the C api 3.2 on linux and would like to have a minimum loop the polls the sensors each frame. This is what I have so far:

#include <iostream>
#include <SDL2/SDL.h>
#include <memory>
#include <OVR_CAPI.h>
#include <OVR_CAPI_GL.h>
#include <chrono>
#include <thread>

using namespace std;

ostream& operator<<(ostream& os, const ovrQuatf& quat) {
    return os << "q(" << quat.x << quat.y << quat.z << quat.w << ")";
}

ostream& operator<<(ostream& os, const ovrVector3f& pos) {
    return os << "vec3(" << pos.x << pos.y << pos.z << ")";
}

ostream& operator<<(ostream& os, ovrPosef pose) {
    return os << "pose(" << pose.Orientation << pose.Position << ")";
}

int main(int argc, char* argv[]){
    for(int i = 0; i < argc; i++) {
        cout << argv << endl;
    }



    if ( !ovr_Initialize() ){
        cout << "can't init ovr" << endl;
    } else {
        cout << "ovr ok" << endl;
    }

    auto hmd = ovrHmd_Create(0);
    if ( hmd == nullptr ) {
        cout << "create debug" << endl;
        hmd = ovrHmd_CreateDebug(ovrHmd_DK1);
    }

    ovrHmdDesc desc;
    ovrHmd_GetDesc(hmd, &desc);

    int ok = SDL_Init(SDL_INIT_EVERYTHING);
    cout << "Hello World! " << ok << endl;

    auto window = SDL_CreateWindow("bla",SDL_WINDOWPOS_CENTERED, SDL_WINDOWPOS_CENTERED,320,240,0);

    SDL_Event event;

    cout << "pseudo render loop" << endl;
    ok = true;
    while (ok) {
        ovrHmd_BeginFrame(hmd,0);
        for (int j = 0; j < ovrEye_Count; j++){
            auto eye = desc.EyeRenderOrder[j];
            ovrPosef pose = ovrHmd_BeginEyeRender(hmd, eye);
            cout << pose;
            ovrHmd_EndEyeRender(hmd, eye, pose, nullptr);
            this_thread::sleep_for(chrono::milliseconds(16));
        }
        ovrHmd_EndFrame(hmd);
        cout << endl;

        SDL_PumpEvents();
        SDL_PollEvent(&event);

        switch(event.type) {
            case SDL_KEYDOWN:
                if (event.key.keysym.scancode == SDL_SCANCODE_ESCAPE) {
                    ok = false;
                }
                break;
            case SDL_WINDOWEVENT_CLOSE:
                ok = false;
                break;
        }
    }

    SDL_DestroyWindow(window);

    ovrHmd_Destroy(hmd);

    ovr_Shutdown();
    SDL_Quit();
    return 0;
}

this is the output:

0x7fffed2f4b98
OVR::DeviceManagerThread - running (ThreadId=0x7f53f352b700).
OVR::DeviceManager - initialized.
ovr ok
*** SensorFusion Startup: TimeSeconds = 1406735779.733282
OVR::Linux::HIDDevice - Opened '/dev/hidraw1'
                    Manufacturer:'Oculus VR, Inc.'  Product:'Tracker DK'  Serial#:'8D82318D4855'
OVR::SensorDevice - Closed '/dev/hidraw1'
OVR::Linux::HIDDevice - HID Device Closed '/dev/hidraw1'
OVR::Linux::HIDDevice - HIDShutdown '/dev/hidraw1'
Hello World! 0
pseudo render loop
pose(q(0001)vec3(000))pose(q(0001)vec3(000))
pose(q(0001)vec3(000))pose(q(0001)vec3(000))
pose(q(0001)vec3(000))pose(q(0001)vec3(000))
pose(q(0001)vec3(000))pose(q(0001)vec3(000))
pose(q(0001)vec3(000))pose(q(0001)vec3(000))
pose(q(0001)vec3(000))pose(q(0001)vec3(000))
pose(q(0001)vec3(000))pose(q(0001)vec3(000))
pose(q(0001)vec3(000))pose(q(0001)vec3(000))
pose(q(0001)vec3(000))pose(q(0001)vec3(000))
pose(q(0001)vec3(000))pose(q(0001)vec3(000))
pose(q(0001)vec3(000))pose(q(0001)vec3(000))
pose(q(0001)vec3(000))pose(q(0001)vec3(000))
pose(q(0001)vec3(000))pose(q(0001)vec3(000))
pose(q(0001)vec3(000))pose(q(0001)vec3(000))
pose(q(0001)vec3(000))pose(q(0001)vec3(000))
pose(q(0001)vec3(000))pose(q(0001)vec3(000))
pose(q(0001)vec3(000))pose(q(0001)vec3(000))
pose(q(0001)vec3(000))pose(q(0001)vec3(000))
pose(q(0001)vec3(000))pose(q(0001)vec3(000))
[...]

the sensors are not able to be moved at all.