[ Version ( since = "1.12" ) ]
public async bool call_waiting_query (Cancellable? cancellable) throws Error
Asynchronously queries the status of the call waiting network service.
When the operation is finished, callback will be invoked in the thread-default main loop of the thread you are
calling this method from. You can then call call_waiting_query.end to get the result of the operation.
See call_waiting_query_sync for the synchronous, blocking version of this method.
| this |
A ModemVoice. |
| cancellable |
A Cancellable or |
| callback |
A TaskReadyCallback to call when the request is satisfied or |
| user_data |
User data to pass to |