How to print variable name in function in C

I want to print the name of a 2D matrix I take as input in a function.

I tried using this I found on the internet:

#include <stdio.h> 
#define VariableName(var) #var   

void saddle(int a[][100], int m, int n)
{
    printf("The saddle points of the matrix %s are: \n", VariableName(a));
}
 `

But on every function call I get the name as a instead of the matrix I entered, eg. A, B, or C.
How to get past this?

VariableName(var) always produces the string "a" in your code. The name of the matrix is only known at the calling site, so you should pass it as an extra argument and you can use the same macro there to create the string:

#include <stdio.h> 

#define VariableName(var) #var   

void saddle(int a[][100], int m, int n, const char *name)
{
    printf("The saddle points of the matrix %s are:\n", name);
}

int main(void)
{
    int matrix[100][100];
    saddle(matrix, 100, 100, VariableName(matrix));
    return 0;
}

Using "matrix" instead of VariableName(matrix) seems simpler, but here is a more advanced version where the matrix name or expression is passed implicitly:

#include <stdio.h> 

#define VariableName(var) #var   

#define saddle(a,m,n)  (saddle)(a, m, n, VariableName(a))
#define print_matrix(a,m,n)  (print_matrix)(a, m, n, VariableName(a))

void (saddle)(int a[][100], int m, int n, const char *name)
{
    printf("The saddle points of the matrix %s are:\n", name);
}

void (print_matrix)(int a[][100], int m, int n, const char *name)
{
    printf("Contents of matrix %s:\n", name);
    for (int i = 0; i < m; i++) {
        for (int j = 0; j < n; i++)
            printf(" %3d", a[i][j]);
        printf("\n");
    }
}

int main(void)
{
    int matrix1[10][100] = { 0 };
    int matrix2[10][100] = { 0 };
    saddle(matrix1, 10, 10);
    saddle(matrix2, 10, 10);
    print_matrix(matrix1, 10, 10);
    print_matrix(matrix2, 10, 10);
    return 0;
}