Native POSIX

Use the native POSIX target for first experiments, CI smoke tests, and ROS 2 interoperability checks on Linux or *BSD. It uses OS sockets, the host process environment, and the same source checkout layout as the embedded targets.

When to Use It

• You want the shortest path to a working nano-ros publisher or subscriber.
• You are validating message generation, CMake integration, or ROS 2 interop before moving to an RTOS.
• Your deployment target is Linux, *BSD, or an embedded Linux system.

Setup

Build the in-tree nros CLI (Phase 218), then provision the native host. For a host build there is no cross-toolchain to fetch — nros setup native installs only the RMW host daemon (zenohd for zenoh, the Micro-XRCE-DDS agent for xrce) into a shared store. ROS 2 is not required.

# Build the in-tree nros CLI:
source ./activate.sh        # OR: direnv allow / source ./activate.fish
just setup-cli              # builds packages/cli/target/release/nros

# Provision the native host (zenoh RMW is the default):
nros setup native --rmw zenoh        # or: --rmw xrce / --rmw cyclonedds

native and posix are accepted as the same board name.

For a colcon consumer workspace that already has nano-ros under src/:

colcon build && source install/setup.bash

Package Layout

For a POSIX application package:

my_posix_node/
├── package.xml
├── Cargo.toml          # Rust path
├── CMakeLists.txt      # C / C++ path
└── src/
    └── main.rs         # or main.c / main.cpp

Keep package beside nano-ros in workspace src/. Use path dependencies for Rust or add_subdirectory(<path-to-nano-ros>) for C/C++.

Code Example

Rust publisher skeleton:

use nros::prelude::*;

fn main() -> Result<(), Box<dyn std::error::Error>> {
    let config = ExecutorConfig::from_env().node_name("talker");
    let mut executor = Executor::open(&config)?;
    let mut node = executor.create_node("talker")?;
    let publisher = node.create_publisher::<std_msgs::msg::Int32>("/chatter")?;

    let mut msg = std_msgs::msg::Int32 { data: 0 };
    loop {
        publisher.publish(&msg)?;
        msg.data += 1;
        executor.spin_once(100);
    }
}

Use the full First Node — Rust walkthrough for generated messages and runnable commands.

Build and Run

Start the RMW host daemon (installed by nros setup native). For zenoh:

zenohd --listen tcp/127.0.0.1:7447

Run the node directly via cargo run (Rust) or cmake --build build && ./build/<binary> (C/C++), or via colcon build && source install/setup.bash && ros2 run … if the package lives in a colcon consumer workspace.

Configuration

Native examples can read runtime settings from the shell:

export ROS_DOMAIN_ID=0
export NROS_LOCATOR=tcp/127.0.0.1:7447

The same fields are compiled into embedded targets through their platform-specific configuration files. See Configuration for the full layering.

Deployment

POSIX deployment is normal process deployment: install the workspace, source install/setup.bash, set environment, and run the binary. For ROS 2 interop, run ROS 2 Interoperability and set the ROS side to rmw_zenoh_cpp.