|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 terminal.|
|-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||Do not display any values for the erase, interrupt and line kill characters.|
|-r||Print the terminal type to the standard error output.|
|-S||Print the terminal type and the termcap entry to the standard output. See the section below on setting the environment for details.|
|-s||Print the sequence of shell commands to initialize the environment variables TERM and TERMCAP 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 terminals capabilities into the shells environment. This is done using the -S and -s options.
When the -S option is specified, the terminal type and the termcap entry are written to the standard output, separated by a space and without a terminating newline. This can be assigned to an array by csh and ksh users and then used like any other shell array.
When the -s option is specified, the commands to enter the information into the shells environment are written to the standard output. If the SHELL environment variable ends in csh, the commands are for the csh, otherwise, they are for sh(1). 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 ... `
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 $term setenv TERMCAP "$term" 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 environment 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 Im on this port at a particular speed, guess that Im 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 users insert a backslash character (\) before any exclamation marks (!).
The tset command utilizes the SHELL and TERM environment variables.
/etc/ttys system port name to terminal type mapping database /usr/share/misc/termcap terminal capability database
The -A , -E , -h , -u and -v options have been deleted from the tset utility. None of them were documented in BSD 4.3 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.
Finally, the tset implementation has been completely redone (as part of the addition to the system of a -p1003.1-88 compliant terminal interface) and will no longer compile on systems with older terminal interfaces.
The tset command appeared in BSD 3.0 .