Invoke a BN_GENCB progress callback with event codes a and b.
1 to continue, or 0 if the callback requested cancellation.
| Name | Description |
|---|---|
| cb | Callback object populated with BN_GENCB_set() or BN_GENCB_set_old(); NULL is ignored. |
| a | Primary event / stage code passed to the callback. |
| b | Secondary progress value passed to the callback. |