1: #include <execinfo.h>
    2: #include <inttypes.h>
    3: #include <stdio.h>
    4: #include <stdlib.h>
    5: 
    6: 
    7: static int
    8: compare (const void *p1, const void *p2)
    9: {
   10:   void *ba[20];
   11:   int n = backtrace (ba, sizeof (ba) / sizeof (ba[0]));
   12:   if (n != 0)
   13:     {
   14:       char **names = backtrace_symbols (ba, n);
   15:       if (names != NULL)
   16:         {
   17:           int i;
   18:           printf ("called from %s\n", names[0]);
   19:           for (i = 1; i < n; ++i)
   20:             printf ("            %s\n", names[i]);
   21:           free (names);
   22:         }
   23:     }
   24: 
   25:   return *(const uint32_t *) p1 - *(const uint32_t *) p2;
   26: }
   27: 
   28: 
   29: int
   30: main (int argc, char *argv[])
   31: {
   32:   uint32_t arr[20];
   33:   size_t cnt;
   34: 
   35:   for (cnt = 0; cnt < sizeof (arr) / sizeof (arr[0]); ++cnt)
   36:     arr[cnt] = random ();
   37: 
   38:   qsort (arr, sizeof (arr) / sizeof (arr[0]), sizeof (arr[0]), compare);
   39: 
   40:   for (cnt = 0; cnt < sizeof (arr) / sizeof (arr[0]); ++cnt)
   41:     printf ("%" PRIx32 "\n", arr[cnt]);
   42: 
   43:   return 0;
   44: }