--- /dev/null
+/* Copyright (c) 2023. The SimGrid Team. All rights reserved. */
+
+/* This program is free software; you can redistribute it and/or modify it
+ * under the terms of the license (GNU LGPL) which comes with this package. */
+
+/* This example shows how to use simgrid::s4u::this_actor::wait() to wait for a given communication.
+ *
+ * As for the other asynchronous examples, the sender initiate all the messages it wants to send and
+ * pack the resulting simgrid::s4u::CommPtr objects in a vector. All messages thus occurs concurrently.
+ *
+ * The sender then loops until there is no ongoing communication.
+ */
+
+#include "simgrid/s4u.hpp"
+#include <cstdlib>
+#include <iostream>
+#include <string>
+namespace sg4 = simgrid::s4u;
+
+XBT_LOG_NEW_DEFAULT_CATEGORY(s4u_mess_wait, "Messages specific for this s4u example");
+
+static void sender(int messages_count)
+{
+ sg4::MessageQueue* mqueue = sg4::MessageQueue::by_name("control");
+
+ sg4::this_actor::sleep_for(0.5);
+
+ for (int i = 0; i < messages_count; i++) {
+ std::string msg_content = "Message " + std::to_string(i);
+ // Copy the data we send: the 'msg_content' variable is not a stable storage location.
+ // It will be destroyed when this actor leaves the loop, ie before the receiver gets the data
+ auto* payload = new std::string(msg_content);
+
+ /* Create a control message and put it in the message queue */
+ sg4::MessPtr mess = mqueue->put_async(payload);
+ XBT_INFO("Send '%s' to '%s'", msg_content.c_str(), mqueue->get_cname());
+ mess->wait();
+ }
+
+ /* Send message to let the receiver know that it should stop */
+ XBT_INFO("Send 'finalize' to 'receiver'");
+ mqueue->put(new std::string("finalize"), 0);
+}
+
+/* Receiver actor expects 1 argument: its ID */
+static void receiver()
+{
+ sg4::MessageQueue* mqueue = sg4::MessageQueue::by_name("control");
+
+ sg4::this_actor::sleep_for(1);
+
+ XBT_INFO("Wait for my first message");
+ for (bool cont = true; cont;) {
+ std::string* received;
+ sg4::MessPtr mess = mqueue->get_async<std::string>(&received);
+
+ sg4::this_actor::sleep_for(0.1);
+ mess->wait();
+
+ XBT_INFO("I got a '%s'.", received->c_str());
+ if (*received == "finalize")
+ cont = false; // If it's a finalize message, we're done.
+ delete received;
+ }
+}
+
+int main(int argc, char* argv[])
+{
+ sg4::Engine e(&argc, argv);
+
+ e.load_platform(argv[1]);
+
+ sg4::Actor::create("sender", e.host_by_name("Tremblay"), sender, 3);
+ sg4::Actor::create("receiver", e.host_by_name("Fafard"), receiver);
+
+ e.run();
+
+ return 0;
+}
