The type iostate is a bitmask type ([bitmask.types]) that contains the elements indicated in Table [tab:iostreams.iostate.effects].
| Element | Effect(s) if set |
| badbit | indicates a loss of integrity in an input or output sequence (such as an irrecoverable read error from a file); |
| eofbit | indicates that an input operation reached the end of an input sequence; |
| failbit | indicates that an input operation failed to read the expected characters, or that an output operation failed to generate the desired characters. |