| Conditions | Result | |
| ios_base::in is set in which | positions the input sequence | |
| ios_base::out is set in which | positions the output sequence | |
| both ios_base::in and ios_base::out are
set in which and either way == ios_base::beg or way == ios_base::end | positions both the input and the output sequences | |
| Otherwise | the positioning operation fails. |