1  #include <mcheck.h>
       2  #include <stdio.h>
       3  #include <string.h>
       4  
       5  extern const char *foo (void);
       6  
       7  int
       8  main (void)
       9  {
      10    const char *s;
      11  
      12    mtrace ();
      13  
      14    s = foo ();
      15  
      16    printf ("called `foo' from `%s'\n", s);
      17  
      18    return strcmp (s, "filtmod2.c");
      19  }