Boolean reading (Scilab gateway)

#include "api_scilab.h"
int read_write_boolean(char *fname,void* pvApiCtx)
{
    SciErr sciErr;
    int i;
    //first variable info : real matrix of double
    int iRows       = 0;
    int iCols       = 0;
    int *piAddr     = NULL;
    int* piBool     = NULL;

    //check input and output arguments
    CheckInputArgument(pvApiCtx, 1,1);
    CheckOutputArgument(pvApiCtx, 1,1);

    //get variable address of the first input argument
    sciErr = getVarAddressFromPosition(pvApiCtx, 1, &piAddr);
    if(sciErr.iErr)
    {
        printError(&sciErr, 0);
        return 0;
    }

    //get size and data from Scilab memory
    sciErr = getMatrixOfBoolean(pvApiCtx, piAddr, &iRows, &iCols, &piBool);
    if(sciErr.iErr)
    {
        printError(&sciErr, 0);
        return 0;
    }

    //Do something with data
    for(i = 0 ; i < iRows * iCols ; i++)
    {
        piBool[i] = piBool[i] == 0 ? 1 : 0;
    }

    sciErr = createMatrixOfBoolean(pvApiCtx, nbInputArgument(pvApiCtx) + 1, iRows, iCols, piBool);
    if(sciErr.iErr)
    {
        printError(&sciErr, 0);
        return 0;
    }

    AssignOutputVariable(pvApiCtx, 1) = nbInputArgument(pvApiCtx) + 1;
    return 0;
}

a = [%t, %f, %t ; %f, %t, %f ; %t, %f, %t];
a_ref = [%f, %t, %f ; %t, %f, %t ; %f, %t, %f];
b = read_write_boolean(a);

if or(b <> a_ref) then error("failed"), end