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TSET(1)                     General Commands Manual                    TSET(1)

     tset, reset - terminal initialization

     tset [-IQrs] [-] [-e ch] [-i ch] [-k ch] [-m mapping] [terminal]

     reset [-IQrs] [-] [-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.

              The terminal argument specified on the command line.
              The value of the TERM environmental variable.
              The terminal type associated with the standard error output
               device in the /etc/ttys file.
              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 a abnormal state.  Note, you may have to type
     "<LF>reset<LF>" (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:

     -     The terminal type is displayed to the standard output, and the
           terminal is not initialized in any way.

     -e    Set the erase character to ch.

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

     -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.

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

     -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 the
     csh(1), otherwise, they are for sh(1).  Note, the csh(1) commands set and
     unset the shell variable "noglob", leaving it unset.  The following line
     in the .login or .profile files will initialize the environment

           eval `tset -s options ... `

     To demonstrate a simple use of the -S option, the following lines in the
     .login file have an equivalent effect:

           set noglob
           set term=(`tset -S options ...`)
           setenv TERM $term[1]
           unset term
           unset noglob

     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
     (.profile for sh(1) users or .login for csh(1) users) 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 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 metacharacters, it is suggested that the entire -m
     option argument be placed within single quote characters, and that csh(1)
     users insert a backslash character (``\'') before any exclamation marks

     The tset command uses the SHELL and TERM environment variables.

     /etc/ttys                 system port name to terminal type mapping
     /usr/share/misc/terminfo  terminal capability database

     The -A, -E, -h, -u and -v options have been deleted from the tset
     utility.  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.
     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.

     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 -E and -S options have been removed as they only make sense for
     termcap and tset now uses terminfo.  As such, the TERMCAP entry has been
     removed from -s.

     Finally, the tset implementation has been completely redone (as part of
     the addition to the system of a IEEE Std 1003.1-1988 ("POSIX.1")
     compliant terminal interface) and will no longer compile on systems with
     older terminal interfaces.

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

     The reset and tset commands appeared in 1BSD.

NetBSD 10.99                     April 5, 2012                    NetBSD 10.99