Getting Started

System Requirements

• POSIX-compliant OS (Ubuntu 22.04 and 24.04 are tested)

• GNU-compliant C++ compiler that supports the C++20 standard

  • gcc 11 or later

  • clang 16 or later

• CMake 3.28 or later

Usage in CMake

To use the Xronos C++ SDK in your CMake project, add one of the following code snippets to your CMakeLists.txt and link your targets with xronos::xronos-sdk. FetchContent downloads the binary artifacts or sources and integrates them with your build. Note that building the Xronos SDK from source may take some time. We recommend using the pre-built binary artifacts.

binary artifactsfrom source

set(XRONOS_SDK_VERSION "0.5.0" CACHE STRING "Xronos SDK version")
include(FetchContent)
FetchContent_Declare(
  "xronos-sdk"
  URL https://github.com/xronos-inc/xronos/releases/download/v${XRONOS_SDK_VERSION}/xronos-sdk-${XRONOS_SDK_VERSION}-Linux-${CMAKE_SYSTEM_PROCESSOR}.tar.gz
)
FetchContent_MakeAvailable(xronos-sdk)
set(xronos-sdk_DIR ${xronos-sdk_SOURCE_DIR}/share/cmake/xronos-sdk)
find_package(xronos-sdk)

Installation (Optional)

Alternatively to the FetchContent method described above, the Xronos SDK can also be installed and used in CMake via find_package(xronos-sdk).

.deb Package

For system-wide installation on Ubuntu 22.04 (or newer) we provide a .deb package. Download the .deb package for your architecture from the release page and install it using the following command.

$ sudo dpkg -i <path-to-your-deb-file>

Binary Artifacts

Alternatively, you can download the .tar.gz archive containing pre-built binary artifacts from the release page. Simply extract the archive in the system root or in a directory of your choice.

$ tar -xf <path-to-your-tar-file> -C <xronos-install-location>

When installing in a location other than /, you will have to use -DCMAKE_INSTALL_PREFIX=<xronos-install-location> when invoking cmake.

Hello World

This section shows you how to write a “Hello, World!” program using the Xronos SDK.

Application Code

In a new directory, create a new file hello.cc and paste the following content into it.

#include <iostream>

#include "xronos/sdk.hh"

namespace sdk = xronos::sdk;

class Hello : public sdk::Reactor {
  using sdk::Reactor::Reactor;

  class HelloReaction : public sdk::Reaction<Hello> {
    using sdk::Reaction<Hello>::Reaction;
    Trigger<void> startup_trigger{self().startup(), context()};
    void handler() final { std::cout << "Hello, World!\n"; }
  };

  void assemble() final { add_reaction<HelloReaction>("hello"); }
};

auto main() -> int {
  sdk::Environment env{};
  Hello hello{"hello", env.context()};
  env.execute();
  return 0;
}

CMake Config

Then create CMakeLists.txt using your preferred method of including the SDK.

binary artifactsfrom sourceinstalled

cmake_minimum_required(VERSION 3.28)

project(hello LANGUAGES CXX)

set(XRONOS_SDK_VERSION "0.5.0" CACHE STRING "Xronos SDK version")
include(FetchContent)
FetchContent_Declare(
  "xronos-sdk"
  URL https://github.com/xronos-inc/xronos/releases/download/v${XRONOS_SDK_VERSION}/xronos-sdk-${XRONOS_SDK_VERSION}-Linux-${CMAKE_SYSTEM_PROCESSOR}.tar.gz
)
FetchContent_MakeAvailable(xronos-sdk)
set(xronos-sdk_DIR ${xronos-sdk_SOURCE_DIR}/share/cmake/xronos-sdk)

find_package(xronos-sdk)

add_executable(hello hello.cc)
target_link_libraries(hello xronos::xronos-sdk)

Build and Run

Configure the CMake project and build the hello world application.

$ cmake -B build
$ cmake --build build --target hello

Then run the program.

$ ./build/hello
Hello, World!

Additional Examples

See https://github.com/xronos-inc/xronos/tree/main/cpp-sdk/examples for additional examples.