_CP_root is equivalent to the root string1, string2 to result BASIC statement.
int _CP_root(CPSTR* string1, CPSTR* string2, int* result)
This function returns -1 if an error occurs. The error code is contained in _CP_errno.
/* Gets the first item-ID which contains "a" as attribute 1. */
CPSTR * n = _CP_mkstr("myfile");
CPSTR * a = _CP_mkstr("a1");
CPSTR * op = _CP_mkstr("n");
CPSTR * k = _CP_mkstr("a");
CPSTR * i = _CP_str_null;
int r,dummy;
_CP_root(n,a,&r);
_CP_key(op,r,&k,&i,&dummy);