The TSPI_phoneGetButtonInfo function returns information about a specified button.
LONG TSPI_phoneGetButtonInfo(
HDRVPHONE hdPhone,
DWORD dwButtonLampID,
LPPHONEBUTTONINFO lpButtonInfo
);
Returns zero if the function succeeds, or an error number if an error occurs. Possible return values are as follows:
PHONEERR_INVALPHONEHANDLE, PHONEERR_OPERATIONFAILED, PHONEERR_INVALBUTTONLAMPID, PHONEERR_OPERATIONUNAVAIL, PHONEERR_INVALPHONESTATE, PHONEERR_RESOURCEUNAVAIL, PHONEERR_NOMEM.
The TSPI_phoneGetButtonInfo function returns the PHONEERR_NOMEM value if the service provider cannot access the memory containing the button information.
The service provider fills in all the members of the PHONEBUTTONINFO data structure, except for dwTotalSize, which is filled in by TAPI. The service provider must not overwrite the dwTotalSize member.
PHONEBUTTONINFO, PHONECAPS, TSPI_phoneSetButtonInfo