tip - connect to a remote system


tip [-nv] -speed system-name
tip [-nv] -speed phone-number


The tip(1) command establishes a full-duplex connection to another computer, giving the appearance of being logged in directly on the remote CPU. You must have a login on the computer (or equivalent) to which you want to connect.

The options are as follows:

Set verbose mode.
No escape (disable tilde).

Typed characters are usually transmitted directly to the remote computer (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 (you can still be logged in on the remote computer).
~c [name]
Change directory to name (no argument implies change to your home directory).
Escape to a shell (exiting the shell will return you to tip(1)).
Copy file from local to remote. The tip(1) command prompts for the name of a local file to transmit.
Copy file from remote to local. The tip(1) command prompts first for the name of the file to be sent, then for a command to be executed on the remote computer.
~p from [to]
Send a file to a remote UNIX host. The put command causes the remote UNIX system to run the command string cat > to, while tip(1) sends it the from file. If the to file name 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 with the put command, the to file name defaults to the from file name if it is not specified. The remote host executes the command string cat from;echo ^A to send the file to tip(1).
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.

Fork a child process on the local system to perform special protocols, such as XMODEM. The child program will be run with the following somewhat unusual arrangement of file descriptors:

0 <-> local tty in
1 <-> local tty out
2 <-> local tty out
3 <-> remote tty in
4 <-> remote tty out

Send a BREAK to the remote system. For systems that do not support the necessary ioctl(2) call, the break is simulated by a sequence of line-speed changes and DEL characters.
Set a variable (see the discussion later in this topic).
Stop tip(1) (only available with job control).
Stop only the local side of tip(1) (only available with job control); the remote side of tip(1), that is, the side that displays output from the remote host, is left running.
Get a summary of the tilde (~)escapes.

The tip(1) command uses the file /etc/remote to determine how to reach a particular system and to then determine how it should operate while talking to the system; see remote for a full description. Each system has a default baud rate with which to establish a connection. If this value is not suitable, the baud rate to be used can be specified on the command line; for example, tip -300 mds.

When tip(1) establishes a connection, it sends out a connection message to the remote system; the default value, if any, is defined in /etc/remote (see remote).

When tip(1) prompts for an argument (for example, during setup of a file transfer) the line typed can 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 you to the remote computer.

The tip(1) command 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.

During file transfers, tip(1) 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 tandem mode for flow control. If the remote system does not support tandem mode, echocheck can be set to indicate tip(1) should synchronize with the remote system on the echo of each transmitted character.

When tip(1) must dial a phone number to connect to a system, it will print various messages indicating its actions. The tip(1) command supports the DEC DN Ns-11 and Racal-Vadic 831 auto-call-units; the DEC DF02 and DF03, Ventel 212+, Racal-Vadic 3451, and Bizcomp 1031 and 1032 integral call unit/modems.


The tip(1) command maintains a set of variables which controls its operation. Some of these variables are read-only to normal users (root is allowed to change anything of interest). Variables can 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 can request a 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 can be reset by prepending a ! to the name. Other variable types are set by concatenating an = and the value. The entire assignment must not contain any blanks. A single set command can be used to interrogate as well as set a number of variables. Variables can be initialized at run time by placing set commands (without the ~s prefix in a file .tiprc in one's home directory). The -v option causes tip(1) 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:

(bool) Discard unprintable characters when a session is being scripted; abbreviated be.
(num) The baud rate at which the connection was established; abbreviated ba.
(num) When dialing a phone number, the time (in seconds) to wait for a connection to be established; abbreviated dial.
(bool) Synchronize with the remote host during file transfer by waiting for the echo of the last character transmitted; default is off.
(str) The set of characters that signify an end-of-transmission during a ~< file transfer command; abbreviated eofr.
(str) The string sent to indicate end-of-transmission during a ~> file transfer command; abbreviated eofw.
(str) The set of characters that indicate an end-of-line. The tip(1) command will recognize escape characters only after an end-of-line.
(char) The command prefix (escape) character; abbreviated es; default value is ~.
(str) The set of characters that should not be discarded due to the beautification switch; abbreviated ex; default value is \t\n\f\b.
(char) The character used to force literal data transmission; abbreviated fo; default value is ^P.
(num) The amount of data (in bytes) to buffer between file system write operations when receiving files; abbreviated fr.
(str) The name of the host to which you are connected; abbreviated ho.
(char) The character that 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.
(bool) Uppercase mapping mode; abbreviated ra; default value is off. When this mode is enabled, all lowercase letters will be mapped to uppercase by tip(1) for transmission to the remote computer.
(char) The input character used to toggle uppercase mapping mode; abbreviated rc; default value is ^A.
(str) The name of the file in which a session script is recorded; abbreviated rec; default value is tip.record.
(bool) Session scripting mode; abbreviated sc; default is off. When script is true, tip(1) will record everything transmitted by the remote computer 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 that are an exception to the normal beautification rules.
(bool) Expand tabs to spaces during file transfers; abbreviated tab; default value is false. Each tab is expanded to eight spaces.
(bool) Verbose mode; abbreviated verb; default is true. When verbose mode is enabled, tip(1) prints messages while dialing, shows the current number of lines transferred during a file transfer operations, and more.


(str) The name of the shell to use for the ~! command; default value is /bin/sh, or taken from the environment.
(str) The home directory to use for the ~c command; default value is taken from the environment.
Check for a default host if none specified.

The variables ${REMOTE} and ${PHONES} are also exported.


Global system descriptions
Global phone number database
Private system descriptions
Private phone numbers
Initialization file
Record file
Line access log
Lock file to avoid conflicts with uucp


The tip appeared command in 4.2BSD.


The full set of variables is undocumented and should probably be pared down.