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tset(1)                 FreeBSD General Commands Manual                tset(1)

       tset, reset - terminal initialization

       tset [-IQVqrs] [-] [-e ch] [-i ch] [-k ch] [-m mapping] [terminal]
       reset [-IQVqrs] [-] [-e ch] [-i ch] [-k ch] [-m mapping] [terminal]

       Tset initializes terminals.  Tset first determines the type of terminal
       that you are using.  This determination is done as follows, using the
       first terminal type found.

       1. The terminal argument specified on the command line.

       2. The value of the TERM environmental variable.

       3. (BSD systems only.) The terminal type associated with the standard
       error output device in the /etc/ttys file.  (On Linux and System-V-like
       UNIXes, getty does this job by setting TERM according to the type
       passed to it by /etc/inittab.)

       4. The default terminal type, ``unknown''.

       If the terminal type was not specified on the command-line, the -m
       option mappings are then applied (see below for more information).
       Then, if the terminal type begins with a question mark (``?''), the
       user is prompted for confirmation of the terminal type.  An empty
       response confirms the type, or, another type can be entered to specify
       a new type.  Once the terminal type has been determined, the terminfo
       entry for the terminal is retrieved.  If no terminfo entry is found for
       the type, the user is prompted for another terminal type.

       Once the terminfo entry is retrieved, the window size, backspace,
       interrupt and line kill characters (among many other things) are set
       and the terminal and tab initialization strings are sent to the
       standard error output.  Finally, if the erase, interrupt and line kill
       characters have changed, or are not set to their default values, their
       values are displayed to the standard error output.

       When invoked as reset, tset sets cooked and echo modes, turns off
       cbreak and raw modes, turns on newline translation and resets any unset
       special characters to their default values before doing the terminal
       initialization described above.  This is useful after a program dies
       leaving a terminal in an abnormal state.  Note, you may have to type


       (the line-feed character is normally control-J) to get the terminal to
       work, as carriage-return may no longer work in the abnormal state.
       Also, the terminal will often not echo the command.

       The options are as follows:

       -q   The terminal type is displayed to the standard output, and the
            terminal is not initialized in any way.  The option `-' by itself
            is equivalent but archaic.

       -e   Set the erase character to ch.

       -I   Do not send the terminal or tab initialization strings to the

       -Q   Don't display any values for the erase, interrupt and line kill

       -V   reports the version of ncurses which was used in this program, and

       -i   Set the interrupt character to ch.

       -k   Set the line kill character to ch.

       -m   Specify a mapping from a port type to a terminal.  See below for
            more information.

       -r   Print the terminal type to the standard error output.

       -s   Print the sequence of shell commands to initialize the environment
            variable TERM to the standard output.  See the section below on
            setting the environment for details.

       The arguments for the -e, -i, and -k options may either be entered as
       actual characters or by using the `hat' notation, i.e. control-h may be
       specified as ``^H'' or ``^h''.

       It is often desirable to enter the terminal type and information about
       the terminal's capabilities into the shell's environment.  This is done
       using the -s option.

       When the -s option is specified, the commands to enter the information
       into the shell's environment are written to the standard output.  If
       the SHELL environmental variable ends in ``csh'', the commands are for
       csh, otherwise, they are for sh.  Note, the csh commands set and unset
       the shell variable noglob, leaving it unset.  The following line in the
       .login or .profile files will initialize the environment correctly:

           eval `tset -s options ... `

       When the terminal is not hardwired into the system (or the current
       system information is incorrect) the terminal type derived from the
       /etc/ttys file or the TERM environmental variable is often something
       generic like network, dialup, or unknown.  When tset is used in a
       startup script it is often desirable to provide information about the
       type of terminal used on such ports.

       The purpose of the -m option is to map from some set of conditions to a
       terminal type, that is, to tell tset ``If I'm on this port at a
       particular speed, guess that I'm on that kind of terminal''.

       The argument to the -m option consists of an optional port type, an
       optional operator, an optional baud rate specification, an optional
       colon (``:'') character and a terminal type.  The port type is a string
       (delimited by either the operator or the colon character).  The
       operator may be any combination of ``>'', ``<'', ``@'', and ``!'';
       ``>'' means greater than, ``<'' means less than, ``@'' means equal to
       and ``!'' inverts the sense of the test.  The baud rate is specified as
       a number and is compared with the speed of the standard error output
       (which should be the control terminal).  The terminal type is a string.

       If the terminal type is not specified on the command line, the -m
       mappings are applied to the terminal type.  If the port type and baud
       rate match the mapping, the terminal type specified in the mapping
       replaces the current type.  If more than one mapping is specified, the
       first applicable mapping is used.

       For example, consider the following mapping: dialup>9600:vt100.  The
       port type is dialup , the operator is >, the baud rate specification is
       9600, and the terminal type is vt100.  The result of this mapping is to
       specify that if the terminal type is dialup, and the baud rate is
       greater than 9600 baud, a terminal type of vt100 will be used.

       If no baud rate is specified, the terminal type will match any baud
       rate.  If no port type is specified, the terminal type will match any
       port type.  For example, -m dialup:vt100 -m :?xterm will cause any
       dialup port, regardless of baud rate, to match the terminal type vt100,
       and any non-dialup port type to match the terminal type ?xterm.  Note,
       because of the leading question mark, the user will be queried on a
       default port as to whether they are actually using an xterm terminal.

       No whitespace characters are permitted in the -m option argument.
       Also, to avoid problems with meta-characters, it is suggested that the
       entire -m option argument be placed within single quote characters, and
       that csh users insert a backslash character (``\'') before any
       exclamation marks (``!'').

       The tset command appeared in BSD 3.0.  The ncurses implementation was
       lightly adapted from the 4.4BSD sources for a terminfo environment by
       Eric S. Raymond <>.

       The tset utility has been provided for backward-compatibility with BSD
       environments (under most modern UNIXes, /etc/inittab and getty(1) can
       set TERM appropriately for each dial-up line; this obviates what was
       tset's most important use).  This implementation behaves like 4.4BSD
       tset, with a few exceptions specified here.

       The -S option of BSD tset no longer works; it prints an error message
       to stderr and dies.  The -s option only sets TERM, not TERMCAP.  Both
       these changes are because the TERMCAP variable is no longer supported
       under terminfo-based ncurses, which makes tset -S useless (we made it
       die noisily rather than silently induce lossage).

       There was an undocumented 4.4BSD feature that invoking tset via a link
       named `TSET` (or via any other name beginning with an upper-case
       letter) set the terminal to use upper-case only.  This feature has been

       The -A, -E, -h, -u and -v options were deleted from the tset utility in
       4.4BSD. None of them were documented in 4.3BSD and all are of limited
       utility at best. The -a, -d, and -p options are similarly not
       documented or useful, but were retained as they appear to be in
       widespread use.  It is strongly recommended that any usage of these
       three options be changed to use the -m option instead.  The -n option
       remains, but has no effect.  The -adnp options are therefore omitted
       from the usage summary above.

       It is still permissible to specify the -e, -i, and -k options without
       arguments, although it is strongly recommended that such usage be fixed
       to explicitly specify the character.

       As of 4.4BSD, executing tset as reset no longer implies the -Q option.
       Also, the interaction between the - option and the terminal argument in
       some historic implementations of tset has been removed.

       The tset command uses the SHELL and TERM environment variables.

            system port name to terminal type mapping database (BSD versions

            terminal capability database

       csh(1), sh(1), stty(1), tty(4), termcap(5), ttys(5), environ(7)



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