There are nine asynchronous operations related to phones. These are initiated by the TSPI_phoneDevSpecific, TSPI_phoneSetButtonInfo, TSPI_phoneSetData, TSPI_phoneSetDisplay, TSPI_phoneSetGain, TSPI_phoneSetHookSwitch, TSPI_phoneSetLamp, TSPI_phoneSetRing, and TSPI_phoneSetVolume functions. If an application calls the TAPI phoneClose function and has the only handle to the phone, TAPI calls the TSPI_phoneClose function to direct the service provider to terminate the asynchronous operations and call the ASYNC_COMPLETION callback function as appropriate. If the application does not have the only handle to the phone, the service provider receives no notification of the request and any outstanding asynchronous operations remain active.