_CP_count is equivalent to the result = count(string1, string2) BASIC statement.
int _CP_count(int* result, CPSTR* string1, CPSTR* string2)
This function returns -1 if an error occurs. The error code is contained in _CP_errno.
/* Prints "2". */
CPSTR * s = _CP_mkstr("bbc");
CPSTR * t = _CP_mkstr("b");
int i;
_CP_count(&i,s,t);
_CP_unix_env();
printf("%d\n", i);