x3270 package includes s3270-

"There is also a scripting-only version of x3270, s3270 3.2. This program is intended primarily for writing "screen-scraping" applications, e.g., a CGI back-end script that retrieves database information from a mainframe."

Depending on how interactive you need to get it might be able to be coerced into doing what you want.

--
Until you've lost your reputation, you never realize what a burden it was or what freedom really is. -Margaret Mitchell