tset(1BSD) (BSD System Compatibility) tset(1BSD)
NAME
tset, reset - (BSD) establish or restore terminal
characteristics
SYNOPSIS
tset [-InQrs] [-ec] [-kc] [-m [port -ID [baudrate] : type] . . .]
[type]
reset [-] [-ec] [-I] [-kc] [-n] [-Q] [-r] [-s]
[-m [indent] [test baudrate]: type] . . . [type]
DESCRIPTION
tset sets up your terminal, typically when you first log in.
It does terminal dependent processing such as setting erase
and kill characters, setting or resetting delays, sending any
sequences needed to properly initialized the terminal, and the
like. tset first determines the type of terminal involved,
and then does necessary initializations and mode settings. If
a port is not wired permanently to a specific terminal (not
hardwired) it is given an appropriate generic identifier such
as dialup.
reset clears the terminal settings by turning off CBREAK and
RAW modes, output delays and parity checking, turns on NEWLINE
translation, echo and TAB expansion, and restores undefined
special characters to their default state. It then sets the
modes as usual, based on the terminal type (which will
probably override some of the above). See stty(1) for more
information. All arguments to tset may be used with reset.
reset also uses rs= and rf= to reset the initialization string
and file. This is useful after a program dies and leaves the
terminal in a funny state. Often in this situation,
characters will not echo as you type them. You may have to
type `<LINEFEED>reset<LINEFEED>' since `<RETURN>' may not
work.
When no arguments are specified, tset reads the terminal type
from the TERM environment variable and re-initializes the
terminal, and performs initialization of mode, environment and
other options at login time to determine the terminal type and
set up terminal modes.
When used in a startup script (.profile for sh(1) users or
.login for csh(1) users) it is desirable to give information
about the type of terminal you will usually use on ports that
are not hardwired. Any of the alternate generic names given
in /usr/share/lib/termcap may be used for the identifier.
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tset(1BSD) (BSD System Compatibility) tset(1BSD)
Refer to the -m option below for more information. If no
mapping applies and a final type option, not preceded by a -m,
is given on the command line then that type is used.
It is usually desirable to return the terminal type, as
finally determined by tset, and information about the
terminal's capabilities, to a shell's environment. This can
be done using the -, -s, or -S options.
For the Bourne shell, put this command in your .profile file:
eval `tset -s options . . .`
or using the C shell, put this command in your .login file:
eval `tset -s options . . .`
With the C shell, it is also convenient to make an alias in
your .cshrc file:
alias tset 'eval `tset -s \!*`'
This also allows the command:
tset 2621
to be invoked at any time to set the terminal and environment.
It is not possible to get this aliasing effect with a Bourne
shell script, because shell scripts cannot set the environment
of their parent. If a process could set its parent's
environment, none of this nonsense would be necessary in the
first place.
Once the terminal type is known, tset sets the terminal driver
mode. This normally involves sending an initialization
sequence to the terminal, setting the single character erase
(and optionally the line-kill (full line erase)) characters,
and setting special character delays. TAB and NEWLINE
expansion are turned off during transmission of the terminal
initialization sequence.
On terminals that can backspace but not overstrike (such as a
CRT), and when the erase character is `#', the erase character
is changed as if -e had been used.
The following options are available with tset:
- The name of the terminal finally decided upon is output
on the standard output. This is intended to be captured
by the shell and placed in the TERM environment
Copyright 1994 Novell, Inc. Page 2
tset(1BSD) (BSD System Compatibility) tset(1BSD)
variable.
-ec Set the erase character to be the named character c on
all terminals. Default is the BACKSPACE key on the
keyboard, usually ^H (CTRL-H). The character c can
either be typed directly, or entered using the
circumflex-character notation used here.
-ic Set the interrupt character to be the named character c
on all terminals. Default is ^C (CTRL-C). The
character c can either be typed directly, or entered
using the circumflex-character notation used here.
-I Suppress transmitting terminal-initialization strings.
-kc Set the line kill character to be the named character c
on all terminals. Default is ^U (CTRL-U). The kill
character is left alone if -k is not specified. Control
characters can be specified by prefixing the
alphabetical character with a circumflex (as in CTRL-U)
instead of entering the actual control key itself. This
allows you to specify control keys that are currently
assigned.
-n Specify that the new tty driver modes should be
initialized for this terminal. Probably useless since
stty new is the default.
-Q Suppress printing the `Erase set to' and `Kill set to'
messages.
-r In addition to other actions, reports the terminal type.
-s Output commands to set and export TERM. This can be
used with
set noglob
eval `tset -s . . .`
unset noglob
to bring the terminal information into the environment.
Doing so makes programs such as vi(1) start up faster.
If the SHELL environment variable ends with csh, C shell
commands are output, otherwise Bourne shell commands are
output.
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tset(1BSD) (BSD System Compatibility) tset(1BSD)
-m [port-ID[baudrate]:type] . . .
Specify (map) a terminal type when connected to a
generic port (such as dialup or plugboard) identified by
port-ID. The baudrate argument can be used to check the
baudrate of the port and set the terminal type
accordingly. The target rate is prefixed by any
combination of the following operators to specify the
conditions under which the mapping is made:
> Greater than
@ Equals or ``at''
< Less than
! It is not the case that (negates the above
operators)
? Prompt for the terminal type. If no response is
given, then type is selected by default.
In the following example, the terminal type is set to
adm3a if the port is a dialup with a speed of greater
than 300 or to dw2 if the port is a dialup at 300 baud
or less. In the third case, the question mark preceding
the terminal type indicates that the user is to verify
the type desired. A NULL response indicates that the
named type is correct. Otherwise, the user's response
is taken to be the type desired.
tset -m 'dialup>300:adm3a' -m 'dialup:dw2' -m \
'plugboard:?adm3a'
To prevent interpretation as metacharacters, the entire
argument to -m should be enclosed in single quotes.
When using the C shell, exclamation points should be
preceded by a backslash (\).
EXAMPLES
These examples all use the `-' option. A typical use of tset
in a .profile or .login will also use the -e and -k options,
and often the -n or -Q options as well. These options have
been omitted here to keep the examples short.
To select a 2621, you might put the following sequence of
commands in your .login file (or .profile for Bourne shell
users).
set noglob
eval `tset -s 2621`
unset noglob
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tset(1BSD) (BSD System Compatibility) tset(1BSD)
If you have a switch which connects to various ports (making
it impractical to identify which port you may be connected
to), and use various terminals from time to time, you can
select from among those terminals according to the speed or
baud rate. In the example below, tset will prompt you for a
terminal type if the baud rate is greater than 1200 (say, 9600
for a terminal connected by an RS-232 line), and use a WyseO
50 by default. If the baud rate is less than or equal to
1200, it will select a 2621. Note the placement of the
question mark, and the quotes to protect the > and ? from
interpretation by the shell.
set noglob
eval `tset -s -m 'switch>1200:?wy' -m 'switch<=1200:2621'`
unset noglob
The following entry is appropriate if you always dial up,
always at the same baud rate, on many different kinds of
terminals, and the terminal you use most often is an adm3a.
set noglob
eval `tset -s ?adm3a`
unset noglob
If you want to make the selection based only on the baud rate,
you might use the following:
set noglob
eval `tset -s -m '>1200:wy' 2621`
unset noglob
The following example quietly sets the erase character to
BACKSPACE, and kill to CTRL-U. If the port is switched, it
selects a Concept 100 for speeds less than or equal to 1200,
and asks for the terminal type otherwise (the default in this
case is a Wyse 50). If the port is a direct dialup, it
selects Concept 100 as the terminal type. If logging in over
the ARPANET, the terminal type selected is a DatamediaO 2500
terminal or emulator. Note the backslash escaping the NEWLINE
at the end of the first line in the example.
set noglob
eval `tset -e -k^U -Q -s -m 'switch<=1200:concept100' -m \
'switch:?wy' -m dialup:concept100 -m arpanet:dm2500`
unset noglob
FILES
.login
Copyright 1994 Novell, Inc. Page 5
tset(1BSD) (BSD System Compatibility) tset(1BSD)
.profile
REFERENCES
csh(1), environ(5), sh(1), stty(1), terminfo(4), vi(1)
NOTICES
The tset command is one of the first commands a user must
master when getting started on a UNIX system. Unfortunately,
it is one of the most complex, largely because of the extra
effort the user must go through to get the environment of the
login shell set.
This program cannot intuit personal choices for erase,
interrupt and line kill characters, so it leaves these set to
the local system standards.
It could well be argued that the shell should be responsible
for ensuring that the terminal remains in a sane state; this
would eliminate the need for the reset program.
Copyright 1994 Novell, Inc. Page 6