====== Configure CLion to run an Open MPI project on Windows ======

===== Install OpenMPI on Ubuntu  =====

After installing WSL2/Ubuntu, run:

<code>
sudo apt-get install openmpi-bin openmpi-common libopenmpi-dev
</code>

===== Configure CLion to use WSL2 =====

{{:c:mpi:pasted:20240221-170356.png}}

===== Change build directory =====

Set build directory to the root project folder:
{{:c:mpi:pasted:20240221-165122.png}}

===== Include MPI references in CMake file =====

<code cmake CMakeLists.txt>
cmake_minimum_required(VERSION 3.2)
project(hellompi)

find_package(MPI REQUIRED)
include_directories(${MPI_INCLUDE_PATH})

SET(CMAKE_C_COMPILER mpicc)
SET(CMAKE_CXX_COMPILER mpicxx)

set(SOURCE_FILES main.c)
add_executable(hellompi ${SOURCE_FILES})
</code>

===== Add source file =====

<code c main.c>
#include <mpi.h>
#include <stdio.h>

int main(int argc, char** argv) {
    // Initialize the MPI environment
    MPI_Init(NULL, NULL);

    // Get the number of processes
    int world_size;
    MPI_Comm_size(MPI_COMM_WORLD, &world_size);

    // Get the rank of the process
    int world_rank;
    MPI_Comm_rank(MPI_COMM_WORLD, &world_rank);

    // Check if the current process is the master process
    if (world_rank == 0) {
        // Master process prints this message
        printf("Hello world from master\n");
    } else {
        // All other processes print this message
        printf("Hello world from processor %d out of %d processors\n",
               world_rank, world_size);
    }

    // Finalize the MPI environment.
    MPI_Finalize();
}
</code>

===== Build the project =====

{{:c:mpi:pasted:20240221-165501.png}}

Reload also cmake project if you have issues:

{{:c:mpi:pasted:20240221-165602.png}}

===== Add a CLion Run Configuration =====

{{:c:mpi:pasted:20240221-165939.png}}

===== Run the project =====

{{:c:mpi:pasted:20240221-170033.png}}