_CP_in is equivalent to the in result for expression BASIC statement.
int _CP_in(int* result, int expression)
If no for clause is used, the user should pass -1 in expression. This function returns -1 if an error occurs. The error code is contained in _CP_errno. If the time out occurs, _CP_errno contains PE_TMOUT.
/* Gets 1 character of input. */
int i;
_CP_in(&i,-1);
_CP_unix_env();
printf("%d\n", i);