Enum DeliveredMessageKind

Enum Documentation

enum class rclcpp::DeliveredMessageKind : uint8_t

The kind of message that the subscription delivers in its callback, used by the executor.

This enum needs to exist because the callback handle is not accessible to the executor’s scope.

“Kind” is used since what is being delivered is a category of messages, for example, there are different ROS message types that can be delivered, but they’re all ROS messages.

As a concrete example, all of the following callbacks will be considered ROS_MESSAGE for DeliveredMessageKind:

  • void callback(const std_msgs::msg::String &)

  • void callback(const std::string &) // type adaption

  • void callback(std::unique_ptr<std_msgs::msg::String>)

Values:

enumerator INVALID
enumerator ROS_MESSAGE
enumerator SERIALIZED_MESSAGE
enumerator DYNAMIC_MESSAGE