You could try the “REMOTE_HOST” CGI variable (in LScript doc.Remote_Host where doc is in the in memory context document) but I doubt you will get what you are looking for. Generally the only thing you get about a client are the browser used and the IP address.
Is this for an internal website or external? If using a Form for the interface you can just add a field called REMOTE_HOST and access it. If using anything else, use the above line of code in your Query_Open.
Redirecting is at times cumbersome, a Java Servlet might be better for what you are trying to do.