WaitForEvent
efi_status (*WaitForEvent) (size_t num_events, efi_event* event, size_t* index) EFIAPI;
WaitForEvent(MSG_QUIT);
void WaitForEvent(uint32 event);
context.WaitForEvent(CliContext::MSG_VALUE_NODE_CHANGED);
context.WaitForEvent(CliContext::MSG_THREAD_STACK_TRACE_CHANGED);
kBootServices->WaitForEvent(1, &event, &index);