TSPI_lineSetAppSpecific function (tspi.h)
The TSPI_lineSetAppSpecific function sets the application-specific field of the specified call's LINECALLINFO structure.
LONG TSPIAPI TSPI_lineSetAppSpecific( HDRVCALL hdCall, DWORD dwAppSpecific );
The handle to the call whose application-specific field is to be set. The call state of hdCall can be any state.
The new content of the dwAppSpecific member for the call's LINECALLINFO structure. This value is uninterpreted by the service provider. This parameter is not validated by TAPI when this function is called.
Returns zero if the function succeeds, or an error number if an error occurs. Possible return values are as follows:
LINEERR_INVALCALLHANDLE, LINEERR_OPERATIONFAILED, LINEERR_NOMEM, LINEERR_RESOURCEUNAVAIL, LINEERR_OPERATIONUNAVAIL.
The application-specific field in the LINECALLINFO data structure that exists for each call is uninterpreted by the Telephony API or any of its service providers. Its usage is entirely defined by the applications. The field can be read from the LINECALLINFO record returned by TSPI_lineGetCallInfo. However, TSPI_lineSetAppSpecific must be used to set the field so that changes become visible to other applications. When this field is changed, the service provider sends a LINE_CALLINFO message with an indication that the AppSpecific field has changed.