Error when executing client for pt1 of challenge

[David-Feldt]

Hi I get this error when trying to execute my client

terminate called after throwing an instance of 'rclcpp::exceptions::RCLInvalidArgument'
  what():  failed to create interrupt guard condition: context argument is null, at /tmp/binarydeb/ros-foxy-rcl-1.1.11/src/rcl/guard_condition.c:65

What could I be doing wrong?

[wmmc88]

Did you call rclcpp::init in your node?

[David-Feldt]

I did not

[wmmc88]

Ah. Try that. I think it should resolve the error.

There may be other things missing in ur code. Have another look at the rclcpp node examples in the ros2 tutorials.

[David-Feldt]

I needed to add the argc and argv to my main and init, turtle has been killed

[niiquaye]

Please take a look at using composition.

[niiquaye]

Can you provide a code snippet?

[David-Feldt]

`#include "rclcpp/rclcpp.hpp"

#include
#include
#include
#include <turtlesim/srv/kill.hpp>

using namespace std::chrono_literals;

int main()
{
std::shared_ptrrclcpp::Node node = rclcpp::Node::make_shared("kill_client");
rclcpp::Clientturtlesim::srv::Kill::SharedPtr client = node->create_clientturtlesim::srv::Kill("/kill");

auto request = std::make_sharedturtlesim::srv::Kill::Request();
request->name = "turtle1";

while (!client->wait_for_service(1s)) {
if (!rclcpp::ok()) {
RCLCPP_ERROR(rclcpp::get_logger("rclcpp"), "Interrupted while waiting for the service. Exiting.");
return 0;
}
RCLCPP_INFO(rclcpp::get_logger("rclcpp"), "service not available, waiting again...");
}

auto result = client->async_send_request(request);
if (rclcpp::spin_until_future_complete(node, result) ==
rclcpp::FutureReturnCode::SUCCESS)
{
RCLCPP_INFO(rclcpp::get_logger("rclcpp"), "Turtle killed");
} else {
RCLCPP_ERROR(rclcpp::get_logger("rclcpp"), "Failed to kill");
}

rclcpp::shutdown();

return 0;
}
`

[niiquaye]

You are using the old ROS1 way of instantiating a client. Take a look at how to create a component. Furthermore, look at the line when you are creating a client, you are missing an angle bracket for the template argument.

[niiquaye]

Take a look at this.