[user02@FC4 Lesson11]$ cat -n chgparam.c

   1  #include <stdio.h>
   2
   3  void change_values(int *a, int *b)
   4  {
   5     *a = 1001;

   6     *b = 1001;
   7
   8     printf("The values within display_values are %d and %d\n", *a, *b);
   9  }
  10
  11  int main(void)
  12  {
  13     int big = 2002, small = 0;
  14
  15     printf("Values before function %d and %d\n", big, small);
  16
  17     change_values(&big, &small);
  18
  19     printf("Values after function %d and %d\n", big, small);
  20
  21     return 0;
  22  }

[user02@FC4 Lesson11]$ gcc -o chgparam chgparam.c
[user02@FC4 Lesson11]$ ./chgparam
Values before function 2002 and 0
The values within display_values are 1001 and 1001
Values after function 1001 and 1001
[user02@FC4 Lesson11]$