cross_language_communication_container

Cross-Language Communication Container

Caution

Every payload you transmit with iceoryx2 must implement [ZeroCopySend] to be compatible with shared memory. Usually, you can use the derive-macro #[derive(ZeroCopySend)] for most types. If you implement it manually you must ensure that the payload type:

• is self contained, no heap, no pointers to external sources
• has a uniform memory representation -> #[repr(C)]
• does not use pointers to manage their internal structure
• and its members don't implement Drop explicitly
• has a 'static lifetime

Data types like String or Vec will cause undefined behavior and may result in segmentation faults. We provide alternative data types that are compatible with shared memory. See the complex data type example for guidance on how to use them.

Only fixed-size integers (like u8), floating-point types (f32 and f64), and the types in the iceoryx2-bb-container library are cross-language compatible!

This example illustrates how the iceoryx2-bb-container C++ and Rust libraries can be used for cross-language communication. We use a StaticVec<u64> with a fixed capacity as payload and add a StaticString with a fixed capacity as the user header.

How to Run

To observe the dynamic communication in action, open two separate terminals and execute the following commands:

Terminal 1

Run the Rust subscriber application:

cargo run --example cross_language_communication_container_subscriber

Terminal 2

Run the Rust publisher application:

cargo run --example cross_language_communication_container_publisher

Tip

You may hit the maximum supported number of ports when too many publisher or subscriber processes are running. Check the iceoryx2 config to set the limits globally or refer to the API of the Service builder to set them for a single service.

How to enable cross-language communication

To enable cross-language communication with containers like StaticVec, the contained type must itself be cross-language compatible. This applies to all fixed-size integer and floating-point types such as u8, i16, f32, and f64. Types like char and bool are not supported because their sizes differ across languages.

iceoryx2 verifies before connecting that the type name, size, and alignment of the payload match, preventing the use of non–cross-language-compatible types.