Backend tool for telnet sessions to IBM mainframes

 b3270 opens a telnet connection to an IBM host, handling the 3270,
 TELNET and TLS protocols, allowing a front-end application handle user
 interactions. It uses XML on its standard input and standard output to
 communicate with the front end.
 .
 b3270 implements RFCs 2355 (TN3270E), 1576 (TN3270) and 1646 (LU name
 selection), and supports IND$FILE file transfer.