Store application-specific data on a BIO at the given ex_data index.
1 on success, or 0 on failure.
| Name | Description |
|---|---|
| bio | BIO that owns the ex_data table. |
| idx | Index obtained from BIO_get_ex_new_index() (or 0 for app data). |
| data | Pointer to store; ownership and lifetime are caller-defined. |