poke: wait indefinitely if --timeout is not specified

Change-Id: I0051e65d27780d8b58a0c0febf3572b0c6a23e8c

tools/peek/ndnpoke/ndnpoke.cpp

@@ -60,10 +60,12 @@ NdnPoke::start()
       m_registeredPrefix.cancel();
     },
     [this] (auto&&) {
-      m_timeoutEvent = m_scheduler.schedule(m_options.timeout, [this] {
-        m_result = Result::TIMEOUT;
-        m_registeredPrefix.cancel();
-      });
+      if (m_options.timeout) {
+        m_timeoutEvent = m_scheduler.schedule(*m_options.timeout, [this] {
+          m_result = Result::TIMEOUT;
+          m_registeredPrefix.cancel();
+        });
+      }
     },
     [this] (auto&&, const auto& reason) {
       m_result = Result::PREFIX_REG_FAIL;

tools/peek/ndnpoke/ndnpoke.hpp

@@ -48,7 +48,7 @@ struct PokeOptions
 
   // program behavior options
   bool wantForceData = false;
-  time::milliseconds timeout = 10_s;
+  optional<time::milliseconds> timeout;
 };
 
 class NdnPoke : boost::noncopyable