Module ros2_client::builtin_interfaces
source · Expand description
Some builtin interfaces for ROS2 communication
Defines message types Duration
and Time
. See builtin_interfaces
The name “builtin_interfaces” is not very descriptive, but that is how it is in ROS.
Type “Time” in ROS 2 can mean either
builtin_interfaces::msg::Time
, which is the message type over the wire, orrclcpp::Time
, which is a wrapper forrcl_time_point_value_t
(in RCL), which again is a typedef forrcutils_time_point_value_t
, which is in packagerclutils
and is a typedef forint64_t
. Comment specifies this to be “A single point in time, measured in nanoseconds since the Unix epoch.” This type is used for time-related computations.
This module defines the over-the wire Time
and Duration
types.
The module ros_time
defines types intended for computaiton and
in-memory representation.
As the over-the wire time representation uses signed 32-bit integer for seconds since the unix epoch, it is susceptible to the Year 2038 problem.
This implementation uses 64-bit nanosecond count in memory, which will not overflow until the year 2262, but the serialization will saturate in 2038.
Structs§
- Over-the wire representation of Duration, i.e. difference between two timestamps.
- Over-the wire representation of a timestamp.