NAME
tip
—
connect to a remote system
SYNOPSIS
tip |
[-nv ]
[- speed]
[system-name] |
DESCRIPTION
Thetip
utility establishes a full-duplex connection to
another machine, giving the appearance of being logged in directly on the
remote CPU. It goes without saying that you must have a login on the machine
(or equivalent) to which you wish to connect.
The options are as follows:
-n
- No escape (disable tilde).
-v
- Set verbose mode.
If speed is specified, it will override any baudrate specified in the system description being used.
If neither speed nor
system-name are specified,
system-name will be set to the value of the
HOST
environment variable.
If speed is specified but
system-name is not, system-name
will be set to a value of “tip
” with
speed appended. For example,
tip
-1200
will set
system-name to
“tip1200
”.
Typed characters are normally transmitted directly to the remote
machine (which does the echoing as well). A tilde
(‘~
’) appearing as the first character
of a line is an escape signal; the following are recognized:
~^D
or~.
- Drop the connection and exit. Only the connection is dropped – the login session is not terminated.
~c
[name]- Change directory to name (no argument implies change to home directory).
~!
- Escape to a shell (exiting the shell will return to
tip
). ~>
- Copy file from local to remote. The
tip
utility prompts for the name of a local file to transmit. ~<
- Copy file from remote to local. The
tip
utility prompts first for the name of the file to be sent, then for a command to be executed on the remote machine. ~p
from [to]- Send a file to a remote UNIX host. This command
causes the remote UNIX system to run the following
command string, sending it the from file:
stty -echo; cat > 'to'; stty echo
If the to file is not specified, the from file name is used. This command is actually a UNIX specific version of the
~>
command. ~t
from [to]- Take a file from a remote UNIX host. As in the
~p
command, the to file defaults to the from file name if it is not specified. The remote host executes the following command string to send the file totip
:cat 'from'; echo '' | tr '\012' '\01'
~|
- Pipe the output from a remote command to a local UNIX process. The command string sent to the local UNIX system is processed by the shell.
~$
- Pipe the output from a local UNIX process to the remote host. The command string sent to the local UNIX system is processed by the shell.
~C
- Fork a child process on the local system to perform special protocols such
as XMODEM. The child program will be run with the following arrangement of
file descriptors:
0 <-> remote tty in 1 <-> remote tty out 2 <-> local tty stderr
~#
- Send a
BREAK
to the remote system. For systems which do not support the necessaryioctl
() call, the break is simulated by a sequence of line speed changes andDEL
characters. ~s
- Set a variable (see the discussion below).
~v
- List all variables and their values (if set).
~^Z
- Stop
tip
(only available with job control). ~^Y
- Stop only the “local side” of
tip
(only available with job control); the “remote side” oftip
, the side that displays output from the remote host, is left running. ~?
- Get a summary of the tilde escapes.
To find the system description, and thus the operating
characteristics of system-name,
tip
searches for a system description with a name
identical to system-name. The search order is as
follows:
- If the environment variable
REMOTE
does not start with a ‘/
’ it is assumed to be a system description, and is considered first. - If the environment variable
REMOTE
begins with a ‘/
’ it is assumed to be a path to a remote(5) database, and the specified database is searched. - The default remote(5) database, /etc/remote, is searched.
See remote(5) for full documentation on system descriptions.
The br capability is used in system
descriptions to specify the baud rate with which to establish a connection.
If the value specified is not suitable, the baud rate to be used may be
given on the command line, e.g. “tip -300
mds
”.
When tip
establishes a connection, it
sends out the connection message specified in the cm
capability of the system description being used.
When tip
prompts for an argument, for
example during setup of a file transfer, the line typed may be edited with
the standard erase and kill characters. A null line in response to a prompt,
or an interrupt, will abort the dialogue and return the user to the remote
machine.
The tip
utility guards against multiple
users connecting to a remote system by opening modems and terminal lines
with exclusive access, and by honoring the locking protocol used by
uucico(8) (ports/net/freebsd-uucp).
During file transfers tip
provides a
running count of the number of lines transferred. When using the
~>
and ~<
commands,
the eofread and eofwrite
variables are used to recognize end-of-file when reading, and specify
end-of-file when writing (see below). File transfers normally depend on
hardwareflow or tandem mode for flow control. If the remote system does not
support hardwareflow or tandem mode, echocheck may be
set to indicate that tip
should synchronize with the
remote system on the echo of each transmitted character.
When tip
must dial a phone number to
connect to a system, it will print various messages indicating its actions.
The tip
utility supports a variety of auto-call
units and modems with the at capability in system
descriptions.
Support for Ventel 212+ (ventel), Hayes AT-style (hayes), USRobotics Courier (courier), Telebit T3000 (t3000) and Racal-Vadic 831 (vadic) units is enabled by default.
Support for Bizcomp 1031[fw] (biz31[fw]), Bizcomp 1022[fw]
(biz22[fw]), DEC DF0[23]-AC (df0[23]), DEC DN-11 (dn11) and Racal-Vadic 3451
(v3451) units can be added by recompiling tip
with
the appropriate defines.
Note that if support for both the Racal-Vadic 831 and 3451 is enabled, they are referred to as the v831 and v3451, respectively. If only one of the two is supported, it is referred to as vadic.
Variables
The tip
utility maintains a set of
variables which control its operation. Some of these variables are read-only
to normal users (root is allowed to change anything of interest). Variables
may be displayed and set through the ~s
escape. The
syntax for variables is patterned after
vi(1)
and Mail(1). Supplying “all
” as an
argument to the set command displays all variables readable by the user.
Alternatively, the user may request display of a particular variable by
attaching a ‘?
’ to the end. For
example, “escape?
” displays the
current escape character.
Variables are numeric, string, character, or boolean values.
Boolean variables are set merely by specifying their name; they may be reset
by prepending a ‘!
’ to the name. Other
variable types are set by concatenating an
‘=
’ and the value. The entire
assignment must not have any blanks in it. A single set command may be used
to interrogate as well as set a number of variables. Variables may be
initialized at run time by placing set commands (without the
~s
prefix) in the initialization file
~/.tiprc; the -v
option
additionally causes tip
to display the sets as they
are made. Certain common variables have abbreviations. The following is a
list of common variables, their abbreviations, and their default values:
- baudrate
- (num) The baud rate at which the connection was established; abbreviated ba.
- beautify
- (bool) Discard unprintable characters when a session is being scripted; abbreviated be.
- dialtimeout
- (num) When dialing a phone number, the time (in seconds) to wait for a connection to be established; abbreviated dial.
- echocheck
- (bool) Synchronize with the remote host during file
transfer by waiting for the echo of the last character transmitted;
default is
off
. - eofread
- (str) The set of characters which signify an
end-of-transmission during a
~<
file transfer command; abbreviated eofr. - eofwrite
- (str) The string sent to indicate
end-of-transmission during a
~>
file transfer command; abbreviated eofw. - eol
- (str) The set of characters which indicate an
end-of-line. The
tip
utility will recognize escape characters only after an end-of-line. - escape
- (char) The command prefix (escape) character;
abbreviated es; default value is
‘
~
’. - exceptions
- (str) The set of characters which should not be
discarded due to the beautification switch; abbreviated
ex; default value is
“
\t\n\f\b
”. - force
- (char) The character used to force literal data
transmission; abbreviated fo; default value is
‘
^P
’. - framesize
- (num) The amount of data (in bytes) to buffer between file system writes when receiving files; abbreviated fr.
- hardwareflow
- (bool) Whether hardware flow control (CRTSCTS) is
enabled for the connection; abbreviated hf; default
value is
off
. - host
- (str) The name of the host to which you are connected; abbreviated ho.
- linedisc
- (num) The line discipline to use; abbreviated ld.
- prompt
- (char) The character which indicates an end-of-line
on the remote host; abbreviated pr; default value is
‘
\n
’. This value is used to synchronize during data transfers. The count of lines transferred during a file transfer command is based on receipt of this character. - raise
- (bool) Upper case mapping mode; abbreviated
ra; default value is
off
. When this mode is enabled, all lowercase letters will be mapped to uppercase bytip
for transmission to the remote machine. - raisechar
- (char) The input character used to toggle uppercase mapping mode; abbreviated rc; not set by default.
- record
- (str) The name of the file in which a session script is recorded; abbreviated rec; default value is tip.record.
- script
- (bool) Session scripting mode; abbreviated
sc; default is
off
. When script istrue
,tip
will record everything transmitted by the remote machine in the script record file specified in record. If the beautify switch is on, only printable ASCII characters will be included in the script file (those characters between 040 and 0177). The variable exceptions is used to indicate characters which are an exception to the normal beautification rules. - tabexpand
- (bool) Expand tabs to spaces during file transfers;
abbreviated tab; default value is
false
. Each tab is expanded to 8 spaces. - tandem
- (bool) Use XON/XOFF flow control to throttle data
from the remote host; abbreviated ta. The default
value is
true
unless the nt capability has been specified in /etc/remote, in which case the default value isfalse
. - verbose
- (bool) Verbose mode; abbreviated
verb; default is
true
. When verbose mode is enabled,tip
prints messages while dialing, shows the current number of lines transferred during a file transfer operations, and more.
ENVIRONMENT
HOME
- The home directory to use for the
~c
command. HOST
- The default value for system-name if none is specified via the command line.
PHONES
- A path to a phones(5) database.
REMOTE
- A system description, or an absolute path to a remote(5) system description database.
SHELL
- The name of the shell to use for the
~!
command; default value is “/bin/sh
”.
FILES
- ~/.tiprc
- initialization file
- tip.record
- record file
- /etc/phones
- default phones(5) file
- /etc/remote
- global remote(5) database
- /var/log/aculog
- line access log
- /var/spool/lock/LCK..*
- lock file to avoid conflicts with uucp(1) (ports/net/freebsd-uucp)
EXAMPLES
Connect to the first USB serial port at the speed of 115200 baud:
tip ucom1 -115200
SEE ALSO
HISTORY
The tip
command appeared in
4.2BSD.
BUGS
The full set of variables is undocumented and should, probably, be pared down.