Unified C++ FIDL bindings examples

This directory contains experimental example code for the nascent unified C++ bindings (fxbug.dev/60240). It follows the structure of /examples/fidl. We can incubate the bindings API here.

To use the unified bindings for a library //examples/fidl/fuchsia.examples, declare the following dependency:

deps = [
    "//examples/fidl/fuchsia.examples:fuchsia.examples_cpp",
]

and include the following header:

#include <fidl/fuchsia.examples/cpp/fidl.h>

After the unified bindings is sufficiently stable for general use, we can move it to the top-level /examples directory.

Client example

Note: the instruction here is adapted from the LLCPP tutorials. We should write a similar full-fledged tutorial for the unified bindings as it matures.

To run the client example, run the echo_realm component. This creates the client and server component instances and routes the capabilities:

ffx component run fuchsia-pkg://fuchsia.com/echo-cpp-client#meta/echo_realm.cm

Then, we can start the echo_client instance:

ffx component start /core/ffx-laboratory:echo_realm/echo_client

The server component starts when the client attempts to connect to the Echo protocol. You should see the following output using fx log:

[echo_server][I] Running echo server
[echo_server][I] Incoming connection for fuchsia.examples.Echo
[echo_client][I] (Natural types) got response: hello
[echo_client][I] (Natural types) got response: hello
[echo_client][I] (Wire types) got response: hello
[echo_server][W] server error: FIDL endpoint was unbound due to peer closed, status: ZX_ERR_PEER_CLOSED (-24)