rlogin -- remote login


rlogin rhost [ -ec ] [ -8 ] [ -E ] [ -L ] [ -l username ]

/usr/hosts/rhost [ -ec ] [ -8 ] [ -E ] [ -L ] [ -l username ]


rlogin connects your terminal on the current local host system lhost to the remote host system rhost.

Each host has a file /etc/hosts.equiv which contains a list of rhost's with which it shares account names. (The host names must be the standard names as described in rcmd(TC).) When you rlogin as the same user on an equivalent host, you do not need to give a password. Users may also have a private equivalence list in a file .rhosts in their login directories. Each line in this file should contain an rhost and a username separated by a space, giving additional cases where logins without passwords are to be permitted. If the originating user is not equivalent to the remote user, then a login and password will be prompted for on the remote machine as in login(M). To avoid some security problems, the .rhosts file must be owned by either the remote user or root.

The remote terminal type is the same as your local terminal type (as given in your environment TERM variable). The terminal or window size is also copied to the remote system if the server supports the option, and changes in size are reflected as well. All echoing takes place at the remote site, so that (except for delays) the rlogin is transparent. Flow control via <Ctrl>s and <Ctrl>q and flushing of input and output on interrupts are handled properly. The optional argument -8 allows an eight-bit input data path at all times; otherwise the input data path is left as per the current local termios(M) settings. The argument -L allows the rlogin session to be run without any output post-processing, (for example, stty -opost.)

A line of the form ``~.'' disconnects from the remote host, where ``~'' is the default escape character.

A line of the form ``~susp'' suspends the login session (only if you are using the Korn shell). ``susp'' is your ``suspend'' character, usually ``^Z'', (CTRL-Z). See stty(C).

An escape character other than ``~'' may be specified with the -e option. There is no space separating this option flag and the argument character. The -E option specifies that no character is to be recognized as the escape character.

Authenticated rlogin using Kerberos

Authenticated rlogin attempts to connect to a different port (klogin) than the standard login port. klogin is assigned to port 543/tcp in /etc/services.

If the connection to the klogin port succeeds in reaching an authenticated rlogind server, then rlogin will establish authentication (using krb5_sendauth). If rlogin cannot connect to klogin, it will abort the connection and retry using the standard login port.

To execute authenticated rlogin, the user must have network credentials, and the user's principal name must appear in the $HOME/.k5login file on the remote host (this file must be writable only by the user or by root, and it must be readable by root in the filesystem where it resides).


Authentication is based on Version 5 of the Kerberos Network Authentication Service protocol. Only this version of the protocol is supported.

Data encryption is not supported.

Using rlogin(TC) to log into a machine running SCO UNIX System V/386 Release 3.2 Operating System Version 4.2 can give the error message bad login user id.

This message appears when a user, already logged in as a non-root user, recursively logs in as root and runs tcp stop followed by tcp start -- see the tcp(ADMN) manual page.

To avoid this error, start TCP/IP using the sd(ADM) command while logged in as root. To do so, enter the following command:

sd tcp start

Only root and other users with the sysadmin authorization are permitted to run sd.

This error does not occur when the destination machine is running an SCO OpenServer system in either of the two lower security modes (``Traditional'' and ``Low'').

If you connect from your machine to a remote machine using rlogin, you receive messages in the default language of the server (the remote machine). The r commands (rcmd, rlogin, rcp) do not pass the LANG to the remote host. The only environment variable passed is TERM. telnet passes many of the user's environment variables including LANG. Therefore, we recommend that you use telnet instead of rlogin if you use your system in a language other than English.


equivalent users for authenticated rlogin

equivalent users

list of trusted hosts

list of Internet services

rhost version of the command

See also

hosts.equiv(SFF), rcmd(TC), rlogind(ADMN), services(SFF)

Standards conformance

rlogin is not part of any currently supported standard. It is an extension of AT&T UNIX System V provided by The Santa Cruz Operation, Inc.

rlogin is conformant with:
RFC 1282

© 2007 The SCO Group, Inc. All rights reserved.
SCO OpenServer Release 6.0.0 -- 05 June 2007