Creating an RPC Interface

Overview

This tutorial walks you through the steps required to define, implement, and register a Remote Procedure Call (RPC) interface on Windows using the Microsoft Interface Definition Language (MIDL) and the RPC runtime.

Prerequisites

• Windows 10 (or later) development environment
• Visual Studio 2022 (or later) with C++ workload
• Basic knowledge of C/C++

Step 1 – Define the Interface

Create a file named MyInterface.idl and add the following MIDL definition:

// MyInterface.idl
import "rpc.idl";

[ 
    uuid(6D2E5E4C-7B8A-4F5A-9B2B-7C0C8F7F1A2B), 
    version(1.0) 
]
interface MyInterface
{
    void HelloWorld([in, string] const wchar_t* name);
};

Step 2 – Generate Stubs

Run the MIDL compiler to generate the client and server stubs:

midl /win64 MyInterface.idl

This creates MyInterface_h.h, MyInterface_c.c, and MyInterface_s.c.

Step 3 – Implement the Server

Implement the RPC function in server.cpp:

#include "MyInterface_h.h"
#include 

void HelloWorld(const wchar_t* name)
{
    std::wcout << L"Hello, " << name << L"!" << std::endl;
}

Compile and link with rpcrt4.lib and the generated server stub (MyInterface_s.c).

Step 4 – Register the Interface

Register the interface using rpcss:

rpcss -r MyInterface.idl

Step 5 – Create the Client

Write a client that calls the RPC function:

#include "MyInterface_h.h"
#include 

int wmain(int argc, wchar_t* argv[])
{
    RPC_STATUS status = RpcBindingFromStringBinding(L"ncacn_ip_tcp:127.0.0.1[12345]", &MyInterface_IfHandle);
    if (status) { std::wcerr << L"Binding failed: " << status << std::endl; return 1; }

    HelloWorld(L"World");
    RpcBindingFree(&MyInterface_IfHandle);
    return 0;
}

Compile with rpcrt4.lib and the client stub (MyInterface_c.c).

Run the Example

Start the server executable first, then run the client. You should see:

Hello, World!