It does not make sence using CORBA to access this small piece C code only to access the COM1 port.
I agree with Jabber that JNI should be used.
But the whole idea sounds like crazy. Why Java and the COM1 together?
If you can treat the COM1 like a character stream (like in BASIC) you may possiblly use File/StreamReader to access the DOS device COM1 for read/write. But the quality of service may not be garanteed.