EG> I want to create a little program in Borland c++ to use under DOS.
EG> This   programm should check the serial port. If there is a
EG> information (from a   ISDN-telefon-system) the program should open a
EG> file and write it in it. My problem is the communication to the
EG> serial port.
It sounds as though what you will need to do is have part of an
asynchronous communication program embedded in your application and
running all the time.  This is no trivial task in DOS.  I would advise
you to use a 3rd party package.  I was going to give you a
recommendation but the company I had in mind (Blaise Computing) has
moved and I can't find their new address.  There should be
advertisements for comperable software packages from other vendors in
magazines, however.
 * KWQ/2 1.2i * 
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