Listing 1

#include <stdio.h>
#include <stdlib.h>
#define NUMELEM(a) (sizeof(a)/sizeof(a[0]))

main()
{
   int cmpia(const void *, const void *);
   int array[] = {25, 3, 22, -5, 3, 24};
   int i;
   
   qsort(&array[0], NUMELEM(array), sizeof(int), cmpia);
   
   printf("ascending integer order\n");
   for (i = 0; i < NUMELEM(array); ++i)
      printf("array[%d] = %2d\n", i, array[i]);
   
   return 0;
}

/*  compare ints in ascending order */

int cmpia(const void *pe1, const void *pe2)
{
   const int *pi1 = pe1;
   const int *pi2 = pe2;
   
   if (*pi1 < *pi2)
      return -1;
   else if (*pi1 == *pi2)
      return 0;
   else
      return 1;
}

Output:
ascending integer order
array[0] = -5
array[1] =  3
array[2] =  3
array[3] = 22
array[4] = 24
array[5] = 25