Note: This special syntax is generally not used from the user interfaces of wc3270 or wx3270, except in scripts or at the x3270> prompt. Those user interfaces allow these options to be specified separately, and construct a properly-formatted host name from them.
The basic syntax is:
- [prefix:...] host [:port] [=accept-name]
A prefix sets an option for a single host session, rather than for all sessions created by the emulator. A prefix is a single letter, separated from the host name by a colon (:), e.g.:
To specify multiple prefixes, separate each of them with a colon, e.g.:
- A - NVT-only session
- Marks the host as supporting NVT mode only. The emulator does not attempt to negotiate 3270 mode, and defaults the terminal name to
xterm(if a monochrome display) or
xterm-color(if a color display, New in 4.2).
- B - No-op
- Formerly caused a change in bind-unlock behavior, but this has now been subsumed by the default value of the bindUnlock resource.
- C - CICS host
- Disables the automatic keyboard lock after connecting to a host, waiting for the host to format the screen. This is needed for CICS hosts, for example, which do not initially format the screen.
- L - Use a TLS tunnel
- Causes the emulator to set up a TLS tunnel for the host connection. TLS negotiation happens before TELNET negotiation, so the entire session is encrypted.
- N - Disable TN3270E
- Disables TN3270E mode. If the host attempts to negotiate TN3270E when this prefix is in use, the emulator will reject it.
- T - No-TELNET host
- Disables the TELNET protocol for the session. The emulator will no longer treat the TELNET IAC character (0xff) specially.
- Y - Disable TLS host certificate checking
- Disables TLS host certificate checking. It overrides the value of the verifyHostCert resource.
The host is either a fully-qualified domain name (e.g.,
foo.bar.com) or a numeric address in either IPv4 dotted-decimal or IPv6 hexadecimal format. A numeric IPv6 addres must be surrounded by square-bracket characters, e.g.,
[100:200::1], to keep the colon characters from being misinterpreted.
The optional port is a number separated from the host name by a colon. It overrides the default value of 23 (the TELNET port).
The optional accept-name is separated from the host and optional port by an equals sign (
=). It overrides the value of the acceptHostname resource, specifying a name to match against the host's TLS certificate.
foo.bar.com without a TLS tunnel, on port 23.
foo.bar.com with a TLS tunnel but not verifying the host certificate, on port 9100.
Connect to IPv4 address
220.127.116.11 on port 23.
Connect to IPv6 address
100:200::1 on port 23.
Connect to IPv6 address
100:200::1 on port 9100 with a TLS tunnel, using
myhost to match the name from the host's TLS certificate.