Add the specified number of hours if the result is valid.
Add to this time interval the specified number of hours. Return 0 if the resulting time interval value is valid (i.e., the days field must not overflow an int) and a non-zero value (with no effect) otherwise.
0 on success, and a non-zero value (with no effect) otherwise
| Name | Description |
|---|---|
| hours | hours to add |