Closing a Serial Port
Other versions of this page are also available for the following:
8/28/2008
Call the CloseHandle function to close a serial port when an application is done using it.
CloseHandle has one parameter, which is the handle returned by the CreateFile function call that opened the port.
There is a two-second delay after CloseHandle is called before the port is closed and resource are freed. This delay allows pending operations to complete.