the ChangeStatus subroutine:
<pre>
   ChangeStatus(in a as integer)
</pre>

This specifies a subroutine that takes one argument.  "In a as integer"
means that there is an argument, a, which is an integer.  It also 
specifies that this is an in parameter.  There are three kinds of
arguments: in, out, and inout (one word).  In parameters are used
when a value should just go in the shared library function.  In the 
case of in arguments, the C code of the shared library expects a simple 
type such as