A version of this page is also available for

Windows Embedded CE 6.0 R3


This function deallocates the specified call handle.


LONG lineDeallocateCall(
  HCALL hCall


  • hCall
    [in] Call handle to be deallocated. An application with monitoring privileges for a call can always deallocate its handle for that call. An application with owner privilege for a call can deallocate its handle unless it is the sole owner of the call and the call is not in the idle state. The call handle is no longer valid after it has been deallocated.

Return Value

Zero indicates success. A negative error number indicates that an error occurred. The following table shows the return values for this function.

Value Description


Invalid call handle


Call is not in the idle state


Not enough memory


The operation failed


The resource is unavailable


The parameter is uninitialized


The deallocation does not affect the call state of the physical call. It does, however, release internal resources related to the call.

In TAPI versions earlier than 2.0, if the application is the sole owner of a call and the call is not in the idle state, LINEERR_INVALCALLSTATE is returned. In this case, the application can first drop the call using the lineDrop function and deallocate its call handle afterwards. An application that has monitor privilege for a call can always deallocate its handle for the call.


Be aware that leaving the call without an owner can result in the user being unable to terminate the call if there are monitoring applications open preventing TAPI from calling TSPI_lineCloseCall. Use this feature only if the application can determine that the call can be controlled externally by the user.

When the lineDeallocateCall function deallocates a call handle, it also suspends further processing of any outstanding LINE_REPLY messages for the call. An application must be designed not to wait indefinitely for LINE_REPLY messages for each corresponding call to an asynchronous function if it also uses the lineDeallocateCall function to deallocate handles.


Header tapi.h
Library coredll.lib
Windows Embedded CE Windows CE 1.0 and later
Windows Mobile Windows Mobile Version 5.0 and later

See Also