Gazebo test case issue 2875 - Modified version of https://github.com/osrf/gazebo/issues/2875#issuecomment-822834452

test.cc

#include <unistd.h>
#include <stdio.h>
#include <signal.h>
#include <gazebo/gazebo.hh>
#include <gazebo/common/common.hh>
#include <gazebo/physics/physics.hh>
#include <gazebo/msgs/msgs.hh>
#include <gazebo/gazebo_client.hh>

volatile sig_atomic_t stop;
const std::string TOPIC = "/chatter";

void inthand(int signum) {
    stop = 1;
}

void cb(ConstGzStringPtr &_msg)
{
  // Dump the message contents to stdout.
  std::cout << _msg->data() << std::endl;
}

// Main function for the child process, runs client
void client_main(int argc, char** argv)
{
  gazebo::client::setup(argc, argv);

  gazebo::transport::NodePtr node(new gazebo::transport::Node());
  node->Init();
  gazebo::transport::SubscriberPtr sub = node->Subscribe(TOPIC, cb);
  while (!stop) {
    gazebo::common::Time::MSleep(10);
  }

  gazebo::client::shutdown();
}

// Main function for the parent process, runs server
void server_main(int argc, char **argv)
{
  gazebo::setupServer(argc, argv);
  gazebo::physics::WorldPtr world = gazebo::loadWorld("worlds/empty.world");

  gazebo::transport::NodePtr node(new gazebo::transport::Node());
  node->Init();

  gazebo::transport::PublisherPtr pub =
    node->Advertise<gazebo::msgs::GzString>(TOPIC);
  pub.reset();

  while (!stop) {
    std::this_thread::sleep_for(std::chrono::milliseconds(100));
    gazebo::msgs::GzString msg;
    msg.set_data("arst");
    // j-rivero: uncommented to make the test to crash
    pub->Publish(msg);
  }

  gazebo::shutdown();
}

/////////////////////////////////////////////////
int main(int argc, char **argv)
{
  signal(SIGINT, inthand);
  if (fork() == 0) {
    client_main(argc, argv);
  } else {
     server_main(argc, argv);
  }
  return 0;
}