The lineShutdown function shuts down the application's usage of the line abstraction of the API.
LONG lineShutdown( HLINEAPP hLineApp );
Application's usage handle for the line API.
Returns zero if the request succeeds or a negative error number if an error occurs. Possible return values are:
LINEERR_INVALAPPHANDLE, LINEERR_RESOURCEUNAVAIL, LINEERR_NOMEM, LINEERR_UNINITIALIZED.
If this function is called when the application has lines open or calls active, the call handles are deleted and TAPI automatically performs the equivalent of a lineClose on each open line. However, it is recommended that applications explicitly close all open lines before invoking lineShutdown. If shutdown is performed while asynchronous requests are outstanding, those requests are canceled.