Function            stroccur - count the occurences of a substring
                                   within a string

  Syntax              int stroccur(str *str, char *substr);

  Prototype in        stringhk.h

  Remarks             stroccur counts the number of times the string
                      substr appears with the string str.

  Return value        returns the number of times the string substr
                      appears within the string str.

  Example             #include <stringhk.h>
                      #include <stdio.h>            /* for the printf */

                      main()
                      {
                           char original[] = "This is his test";

                           printf("%d\n",stroccur(original,"is"));
                      }

  Program output      3