Walter
We use a product called Symphonia that creates a complete OCX/DLL to handle the comminication and parsing of HL7 messages. The downside is I can't parse messages from VFP (probably because I'm not smart enough), but it came with several examples in Visual Basic. So I created a listener in Visual Basic to receive and parse HL7 message and send back acks/nacks. Using the OCX/DLL I can create messages to send out from VFP. It's not cheap, around 5000 plus a run-time license for the user. As a side note, I was able to use winsock to create a listener in VFP, but once I received the message, I had to parse it, and this is a real pain. With the OCX/DLL, once it receives the message, you can just just ask for specific items:
lcLastName=oMsg.Adt01.Patient.LastName
lcFirstName=oMsg.Adt01.Patient.FirstName
etc...
I hope this is helpful.
Kirk