How to use complex data type in MKL C program?

Dear all:

I am facing a problem on how to use lapack_complex_double data type, Including multiply, divide,conjugate(I can do this using z_imag=-z_imag, is this the best way?), and print the results(actually I can print the result, but every time I need a cast (double)z.real, (double)z.imag, which is not convenient).I have tried cast the variable (double complex) z the multiply, but it failed. I will give my sample program. Anyone please kindly show me how I can handle this data type. Please modify on my program so that I can see clear how this is done. I am a novice in both C and MKL programming. I have searched this site and found some similar thread, but I still cannot work it out. 

Below is my program, you can do the matrix element operations using matrix m in it. 

#include    <complex.h>
#include    <math.h>
#include    <stdlib.h>
#include    <stdint.h>
#include    <stdio.h>
#include    <mkl.h>
lapack_int LAPACKE_zheev( int matrix_order, char jobz, char uplo, lapack_int n, lapack_complex_double* a, lapack_int lda, double* w );
//hermitian matrix, each row in output is an eigenvector
void    diag(lapack_complex_double *mat, double *e, lapack_int n)
{
    char    jobz='V';   //also eigenvectors
    char    uplo='U';   //upper triangle
    lapack_int  info;

    info=LAPACKE_zheev(LAPACK_ROW_MAJOR,jobz,uplo,n,mat,n,e);

    if(info!=0){
        printf("matrix diag fail,the %d argument is wrong\n",info);
        exit(1);
    }
}

int main()
{
    lapack_complex_double *mat;
    lapack_complex_double *m;
    double  *e;

    mat=(lapack_complex_double *)malloc(sizeof(lapack_complex_double)*4);
    m=(lapack_complex_double *)malloc(sizeof(lapack_complex_double)*4);
    e=(double *)malloc(sizeof(double)*2);
    mat[0].real=1.0;    mat[0].imag=0.0;
    mat[1].real=1.0;    mat[1].imag=-1.0;
    mat[2].real=1.0;    mat[2].imag=1.0;
    mat[3].real=2.0;    mat[3].imag=0.0;
    *m=*mat;
    *(m+1)=*(mat+1);
    *(m+2)=*(mat+2);
    *(m+3)=*(mat+3);
diag(mat,e,2);

    printf("{(%f,+%fI),(%f,+%fI)}\n",(double)m[0].real,(double)m[0].imag,(double)m[1].real,(double)m[1].imag);
    printf("{(%f,+%fI),(%f,+%fI)}\n",(double)m[2].real,(double)m[2].imag,(double)m[3].real,(double)m[3].imag);
    printf("the eigenvalue is %f,%f\n",e[0],e[1]);

    printf("{(%f,+%fI),(%f,+%fI)}\n",(double)mat[0].real,(double)mat[0].imag,(double)mat[1].real,(double)mat[1].imag);
    printf("{(%f,+%fI),(%f,+%fI)}\n",(double)mat[2].real,(double)mat[2].imag,(double)mat[3].real,(double)mat[3].imag);

    printf("{(%f,+%fI),(%f,+%fI)}\n",(double)mat[0].real,(double)mat[0].imag,(double)mat[1].real,(double)mat[1].imag);
    printf("{(%f,+%fI),(%f,+%fI)}\n",(double)mat[2].real,(double)mat[2].imag,(double)mat[3].real,(double)mat[3].imag);
    free(mat);
    free(m);
    free(e);
    return 0;
}

By the way, I am using gcc, below is my Makefile so that you may need when you compile the above program.

NAME=upload
OBJECTS = $(NAME).c
cc = gcc
MKLPATH=/opt/intel/composer_xe_2013.5.192/mkl/lib/intel64
MKLINCLUDE=/opt/intel/composer_xe_2013.5.192/mkl/include
MODPATH=/opt/intel/composer_xe_2013.5.192/mkl/include/intel64/lp64
FLAGS= -L$(MKLPATH) -I$(MKLINCLUDE)  -I$(MODPATH)    -lmkl_intel_lp64 -lmkl_intel_thread -lmkl_core  -liomp5 -lm -lpthread

OUTNAME=$(NAME).out

$(NAME): $(OBJECTS)
    $(cc) -o $(OUTNAME) $(OBJECTS) $(FLAGS)
clean:
    rm -f $(OUTNAME)

Another question is how I can easily do the matrix-matrix multiply and matrix-vector multiply using C program. Is there any function in MKL or something can do this? If so, can you add that to the above program? thanks very much!