Clear MATLAB command window from mex function

I have a for loop in a mexFunction, which displays some information at every iteration. Consider this simple code, which will print 100 lines in the MATLAB command window and update at every iteration:

#include "mex.h"
#include <iostream>
#include <sstream>
#include <stdio.h>      
#include <stdlib.h>     
#include <time.h>       

using namespace std;

/* The gateway function */
void mexFunction(int nlhs, mxArray *plhs[],
    int nrhs, const mxArray *prhs[])
{
    int numiters = 100;
    /* initialize random seed: */
    srand(time(NULL));

    for (int iter = 1; iter <= numiters; ++iter)
    {
        int rand_num = rand() % 100 + 1;

        /* Print info in matlab */
        std::ostringstream buffer;
        buffer << "iter = " << iter << " of " << numiters << 
            ". random number = " << rand_num << endl;

        /* need something similar to clc here */
        mexPrintf("%s", buffer.str().c_str());
    }
    return;
}

At every iteration I wish to clear MATLAB's command window before calling mexPrintf().

I am aware that I can use mexCallMATLAB, to invoke MATLAB's clc, but I am not sure if invoking MATLAB at every iteration is very efficient, hence I need a solution native to C++.

Solution

My assumption about mexCallMATLAB being inefficient was wrong, thanks to @Ander Biguri for the heads up. I used the following test code to compare times with and without mexCallMATLAB.

TL;DR - TIMING RESULTS

With mexCallMATLAB(0, NULL, 0, NULL, "clc");: mean time per iteration = 0.1016885 sec
Without mexCallMATLAB(0, NULL, 0, NULL, "clc");: mean time per iteration = 0.0978730 sec

DETAILS

Test Bench Summary

Create a vector with 1 million random integers and take the mean.
Repeat for 500 iterations.
Compute time required for each iteration and save in vector.
Average iteration times to get mean time per iteration.

Code

#include "mex.h"
#include <iostream>
#include <sstream>
#include <stdio.h>      /* printf, scanf, puts, NULL */
#include <stdlib.h>     /* srand, rand */
#include <time.h>       /* time */
#include <ctime>
#include <vector>

using namespace std;
extern bool ioFlush(void);

/* The gateway function */
void mexFunction(int nlhs, mxArray *plhs[],
    int nrhs, const mxArray *prhs[])
{
    int numiters = 500;
    /* initialize random seed: */
    srand(time(NULL));

    std::vector<double> all_times(numiters);

    for (int iter = 1; iter <= numiters; ++iter)
    {
        /* tic */
        clock_t begin = clock();

        std::vector<int> rand_vec;

        for(std::size_t i = 0; i < 1000000; ++i)
            rand_vec.push_back( rand() % 100 + 1 );

        double vec_mean = 0.0;
        for(std::size_t i = 0; i < rand_vec.size(); ++i)
            vec_mean += rand_vec[i];

        vec_mean /= rand_vec.size();

        /* clear screen */
        mexCallMATLAB(0, NULL, 0, NULL, "clc");

        /* toc */
        double time_elapsed = double(clock() - begin) / CLOCKS_PER_SEC;

        /* Print data in matlab */
        std::ostringstream buffer;
        buffer << "iter " << iter << " of " << numiters << 
                ". random vector mean = " << vec_mean << 
                ". in " << time_elapsed << "s" << endl;

        mexPrintf("%s", buffer.str().c_str());
        ioFlush();

        all_times[iter] = time_elapsed;
    }

    double avg_time = 0.0;
    for(std::size_t i = 0; i < all_times.size(); ++i)
        avg_time += all_times[i];

    avg_time /= all_times.size();
    mexPrintf("\navg time per iter = %3.7f\n", avg_time);

    return;
}

Note the use of ioFlush() which is an undocumented function needed to update command window at every iteration. See more details about it here.

To Compile

On Windows using Visual Studio: Add #pragma comment(lib, "libmwservices.lib") in source file.
On Ubuntu using gcc: Compile using mex yourFile.cpp -lmwservices