uint8_t * stream;

// Sends to its cartesian neighbours
MPI_Isend(stream, sizeof(stream) * sizeof(MPI_UINT8_T), MPI_UINT8_T, neighbours[j], 0, MPI_COMM_WORLD, &req);
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// If I create a new var uint8_t recv_stream[1000];, somehow recv_stream will start with stream's values.
MPI_Irecv(stream, 1000, MPI_UINT8_T, MPI_ANY_SOURCE, 0, MPI_COMM_WORLD, &req);
MPI_Wait(&req, &stat);

printf("RANK %d, SOURCE %d, RECIEVED: %d\n", rank, stat.MPI_SOURCE, stream);