-/******************************************************************************/
-/* SIMIX_comm_copy_data callbacks */
-/******************************************************************************/
-// XBT_ATTRIB_DEPRECATED_v333
-void SIMIX_comm_set_copy_data_callback(void (*callback)(simgrid::kernel::activity::CommImpl*, void*, size_t))
+namespace simgrid::kernel::activity {
+xbt::signal<void(CommImpl const&)> CommImpl::on_start;
+xbt::signal<void(CommImpl const&)> CommImpl::on_completion;
+
+std::function<void(CommImpl*, void*, size_t)> CommImpl::copy_data_callback_ = &s4u::Comm::copy_pointer_callback;
+
+void CommImpl::set_copy_data_callback(const std::function<void(CommImpl*, void*, size_t)>& callback)