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RedHat 9 (Linux i386) - man page for reset (redhat section 1)

tset(1) 			     General Commands Manual				  tset(1)

NAME
       tset, reset - terminal initialization

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

DESCRIPTION
       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 val-
       ues before doing the terminal initialization described above.  This is useful after a pro-
       gram dies leaving a terminal in an 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:

       -q   The  terminal  type is displayed to the standard output, and the terminal is not ini-
	    tialized 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 terminal.

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

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

       -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''.

SETTING THE ENVIRONMENT
       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 ... `

TERMINAL TYPE MAPPING
       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  termi-
       nal 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 speci-
       fied, 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 (``!'').

HISTORY
       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 <esr@snark.thyrsus.com>.

COMPATIBILITY
       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 omitted.

       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 interac-
       tion  between  the  - option and the terminal argument in some historic implementations of
       tset has been removed.

ENVIRONMENT
       The tset command uses the SHELL and TERM environment variables.

FILES
       /etc/ttys
	    system port name to terminal type mapping database (BSD versions only).

       /usr/share/terminfo
	    terminal capability database

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

											  tset(1)


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