diff -rcN mos-ipc/nre/apps/ipc/delegate/delegate.cc mos-ipc-sol/nre/apps/ipc/delegate/delegate.cc
*** mos-ipc/nre/apps/ipc/delegate/delegate.cc	2017-11-07 15:53:46.103152306 +0100
--- mos-ipc-sol/nre/apps/ipc/delegate/delegate.cc	2015-12-02 09:22:34.000000000 +0100
***************
*** 24,37 ****
  
  PORTAL static void portal_getcap(void*) {
      UtcbFrameRef uf;
!     // TODO delegate cap
  }
  
  PORTAL static void portal_echo(void*) {
      UtcbFrameRef uf;
!     // TODO receive integer
      uf.finish_input();
!     // TODO echo integer back
  }
  
  // provides the echo portal
--- 24,38 ----
  
  PORTAL static void portal_getcap(void*) {
      UtcbFrameRef uf;
!     uf.delegate(echo->sel());
  }
  
  PORTAL static void portal_echo(void*) {
      UtcbFrameRef uf;
!     int x;
!     uf >> x;
      uf.finish_input();
!     uf << x;
  }
  
  // provides the echo portal
***************
*** 42,51 ****
  
  // wants to call the echo portal
  static void client(Pt &getcap) {
!     // TODO request echo portal cap
  
      int res;
!     // TODO call portal
  
      Serial::get() << "Hello World: " << res << "\n";
  }
--- 43,64 ----
  
  // wants to call the echo portal
  static void client(Pt &getcap) {
!     capsel_t cap = CapSelSpace::get().allocate(1);
!     {
!         UtcbFrame uf;
!         uf.delegation_window(Crd(cap,0,Crd::OBJ_ALL));
!         getcap.call(uf);
!     }
  
+     // call portal
      int res;
!     {
!         Pt echopt(cap);
!         UtcbFrame uf;
!         uf << 42;
!         echopt.call(uf);
!         uf >> res;
!     }
  
      Serial::get() << "Hello World: " << res << "\n";
  }
diff -rcN mos-ipc/nre/apps/ipc/echo/echo.cc mos-ipc-sol/nre/apps/ipc/echo/echo.cc
*** mos-ipc/nre/apps/ipc/echo/echo.cc	2017-11-07 15:29:27.146550292 +0100
--- mos-ipc-sol/nre/apps/ipc/echo/echo.cc	2015-12-02 09:21:23.000000000 +0100
***************
*** 22,31 ****
  
  PORTAL static void portal_echo(void*) {
      UtcbFrameRef uf;
!     int val;
!     uf >> val;
      uf.finish_input();
!     uf << val;
  }
  
  int main() {
--- 22,31 ----
  
  PORTAL static void portal_echo(void*) {
      UtcbFrameRef uf;
!     int x;
!     uf >> x;
      uf.finish_input();
!     uf << x;
  }
  
  int main() {
diff -rcN mos-ipc/nre/apps/ipc/service/service.cc mos-ipc-sol/nre/apps/ipc/service/service.cc
*** mos-ipc/nre/apps/ipc/service/service.cc	2015-12-02 09:27:19.000000000 +0100
--- mos-ipc-sol/nre/apps/ipc/service/service.cc	2015-12-02 09:21:23.000000000 +0100
***************
*** 19,25 ****
  using namespace nre;
  
  PORTAL static void portal_echo(void*) {
!     // TODO implement me
  }
  
  int main() {
--- 19,29 ----
  using namespace nre;
  
  PORTAL static void portal_echo(void*) {
!     UtcbFrameRef uf;
!     int x;
!     uf >> x;
!     uf.finish_input();
!     uf << x;
  }
  
  int main() {