ct
PURPOSE
Dials an attached terminal and issues a login process.
SYNOPSIS
ct [-w n][-x n][-h][-v][-s speed] telno...
DESCRIPTION
The Basic Networking Utilities (BNU) command ct enables a
user on a remote ASCII terminal, such as an IBM 3161 or a
DEC VT100, to communicate with an RT PC over a telephone
line attached to a modem at each end of the connection.
The user on the remote terminal can then log in and work
on the RT PC.
A user on the local system issues ct with the appropriate
telephone number to call the modem attached to the remote
terminal. When the connection is established, ct issues
an AIX login prompt that is displayed on the remote ter-
minal. The user on the remote terminal enters an AIX
login name at the prompt, and AIX opens a new shell. The
user at the remote terminal then proceeds to work on the
RT PC just like a local user.
Note: In order to establish a ct connection, the remote
user generally contacts a local user (with a regular
phone call) and asks the local user to issue the command.
The ct command is useful in the following situations:
o When a user working offsite needs to communicate with
a local system under strictly supervised conditions.
Because the local system contacts the remote ter-
minal, the remote user does not need to know the
phone number of the local system.
o When the cost of the connection should be charged
either to the local site, or to a specific account on
the calling RT PC. If the remote user has the appro-
priate access permission and can make outgoing calls
on the attached modem, that user can make the equiv-
alent of a collect call. The remote user calls the
specified local system, logs in, and issues the phone
number of the remote terminal without the -h flag.
The local system hangs up the initial link so that
the remote terminal is free for an incoming call, and
then calls back to the modem attached to the remote
terminal.
Note: Before issuing the ct command, be certain that the
remote terminal is attached to a modem that can answer
the telephone.
The ct command is not as flexible as the BNU command cu.
For example, the user can not issue AIX commands on the
local system while connected to a remote system via ct.
However, the ct command does have two features not avail-
able with cu:
o The user can instruct ct to continue dialing the
specified number until the connection is established
or a set amount of time has elapsed.
o The user can specify more than one telephone number
at a time to instruct ct to continue dialing each
modem until a connection is established over one of
the lines.
If the user specifies alternate dialing paths by entering
more than one number on the command line, ct tries each
line listed in the file /usr/adm/uucp/Devices until it
finds an available line with appropriate attributes, or
runs out of entries. If there are no free lines, ct asks
if it should wait for one, and if so, for how many
minutes. The ct command continues to try to open the
dialers at 1-minute intervals until the specified time is
exceeded. The user can override this prompt by speci-
fying a time with the -wn flag when entering the command.
After the user logs out, ct prompts the user on the
remote terminal with a reconnect option; the system can
either display a new login prompt drop the line.
FLAGS
-wn Allows the dialogue to be overridden by speci-
fying n as the maximum number of minutes that ct
is to wait for a line. The command then dials
the remote modem at 1-minute intervals until the
connection is established or the specified time
has elapsed.
-xn Used for debugging. Produces detailed informa-
tion about the command's execution on standard
error output on the local system. The debugging
level, n, is a single digit between 0 and 9.
The recommended default is 9.
-h Prevents ct from hanging up the current line to
answer an incoming call.
-v Allows ct to send a running narrative to
standard error output.
-sspeed Sets the data rate where speed is expressed in
baud. The default is 1200.
telno Specifies the telephone number of the modem
attached to the remote terminal. The telno may
include the digits 0 - 9, minus signs (-)
representing delays, equal signs (=) repres-
enting secondary dial tones, asterisks (*), and
pound/number signs (#). The phone number may
contain a maximum of 31 characters.
EXAMPLES
1. To connect to a modem with an internal number 4-1589
(the - is optional):
ct 41589
The system responds:
Allocated dialer at 1200 baud
Confirm hang_up? (y to hang_up)
2. To dial a modem connected to a local telephone number
(dialing 9 for an outside line and specifying a
3-minute wait time):
ct -w3 9=2453017
3. To dial a long-distance number (specifying an outside
line and a 5-minute wait):
ct -w5 9=15026647003
FILES
/usr/adm/uucp/Devices Information about avail-
able devices.
/usr/adm/uucp/Dialcodes Dialing code abbrevi-
ations.
/usr/adm/uucp/Dialers Initial handshaking on a
link.
/usr/adm/uucp/Permissions Access permission codes.
/usr/adm/uucp/Systems Accessible remote
systems.
RELATED INFORMATION
The following commands: "cu" and "login."