| Syntax | LONG TSPI_phoneGetButtonInfo(dwRequestID, hdPhone, dwButtonLampID, lpButtonInfo) This function returns information about the specified button. |
| Parameters | DRV_REQUESTID dwRequestID Specifies the identifier of the asynchronous request. The Service Provider returns this value if the function completes asynchronously. |
| HDRVPHONE hdPhone Specifies the Service Provider's opaque handle to the phone to be queried. | |
| DWORD dwButtonLampID Specifies a button on the phone device. | |
| LPPHONEBUTTONINFO lpButtonInfo Specifies a far pointer to a variable sized structure of type PHONEBUTTONINFO. This data structure describes the mode, the function, and provides additional descriptive text corresponding to the button. | |
| Return Value | Returns zero if the function is successful, the (positive) dwRequestID value if the function will be completed asynchronously, or a negative error number if an error has occurred. Possible error returns are: |
| PHONEERR_INVALPHONEHANDLE The specified device handle is invalid. | |
| PHONEERR_INVALBUTTOMLAMPID The specified button/lamp ID is invalid. | |
| PHONEERR_INVALPOINTER The specified pointer parameter is invalid. | |
| PHONEERR_OPERATIONUNAVAIL The specified operation is not available. | |
| PHONEERR_OPERATIONFAILED The specified operation failed for unspecified reasons. | |
| Comments | None. |
| See Also | Functions: TSPI_phoneSetButtonInfo Data Types: PHONEBUTTONINFO, PHONECAPS |
| Fields: | The following table indicates which fields of the PHONEBUTTONINFO data structure are filled in by the Service Provider and which fields are filled in by the TAPI DLL. The Service Provider must preserve (i.e., must not overwrite) the values filled in by the TAPI DLL. |
| Field Name | TAPI DLL | Service Provider |
| dwTotalSize; | X | |
| dwNeededSize; | X | |
| dwUsedSize; | X | |
| dwButtonMode; | X | |
| dwButtonFunction; | X | |
| dwButtonTextSize; | X | |
| dwButtonTextOffset; | X | |
| dwDevSpecificSize; | X | |
| dwDevSpecificOffset; | X |