tset(1)

DESCRIPTION

tset sets up the terminal when logging in on an HP-UX system. It does terminal-dependent processing, such as setting erase and kill characters, setting or resetting delays, and sending any sequences needed to properly initialize the terminal. It first determines the type of terminal involved, then does the necessary initializations and mode settings. The type of terminal attached to each HP-UX port is specified in the /etc/ttytype data base. Type names for terminals can be found in the files under the /usr/share/lib/terminfo directory (see terminfo(4)). If a port is not wired permanently to a specific terminal (not hardwired), it is given an appropriate generic identifier, such as dialup.

reset performs a similar function, setting the terminal to a sensible default state.

In the case where no arguments are specified, tset simply reads the terminal type out of the environment variable TERM and re-initializes the terminal. The rest of this manual entry concerns itself with mode and environment initialization, typically done once at login, and options used at initialization time to determine the terminal type and set up terminal modes.

When used in a startup script (.profile for sh(1), or .login for csh(1) users), it is desirable to give information about the type of terminal that will normally be used on ports that are not hardwired. These ports are identified in /etc/ttytype as dialup or plugboard, etc. To specify what terminal type you usually use on these ports, the -m (map) option flag is followed by the appropriate port type identifier, an optional baud rate specification, and the terminal type. (The effect is to "map" from some conditions to a terminal type; that is, to tell tset that "If I am on this kind of port, I will probably be on this kind of terminal.") If more than one mapping is specified, the first applicable mapping prevails. A missing port type identifier matches all identifiers. A baudrate is specified as with stty (see stty(1)), and is compared with the speed of the diagnostic output (which should be the control terminal). The baud rate test can be any combination of >, =, <, @, and !. @ is a synonym for =, and ! inverts the sense of the test. To avoid problems with metacharacters, it is best to place the entire argument to -m within single quotes; users of csh(1) must also put a \ before any ! used.

Thus,

causes the terminal type to be set to an HP 2622 if the port in use is a dialup at a speed greater than 300 baud, or to an HP 2624 if the port is otherwise a dialup (i.e., at 300 baud or less). If the type finally determined by tset begins with a question mark, the user is asked for verification that the type indicated is really the one desired. A null response means to use that type; otherwise, another type can be entered. Thus, in the above case, if the user is on a plugboard port, he or she will be asked whether or not he or she is actually using an HP 2623.

If no mapping applies and a final type option, not preceded by a -m, is given on the command line, that type is used. Otherwise, the identifier found in the /etc/ttytype data base is taken to be the terminal type. The latter should always be the case for hardwired ports.

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 option. From sh(1), the command:

or using the C shell, (csh(1)):

These commands cause tset to generate as output a sequence of shell commands which place the variable TERM in the environment; see environ(5).

Once the terminal type is known, tset engages in terminal mode setting. This normally involves sending an initialization sequence to the terminal, setting the single character erase (and optionally the full line erase or line-kill) characters, and setting special character delays. Tab and new-line 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 default erase character (# on standard systems), the erase character is changed to Backspace.

EXTERNAL INFLUENCES

EXAMPLES

These examples all assume the sh(1). Note that a typical use of tset in a .profile also uses the -e and -k options, and often the -m or -Q options as well. These options have been omitted here to keep the examples small.

Assume, for the moment, that you are on an HP 2622. This is suitable for typing by hand but not for a .profile unless you are always on a 2622.

Assume you have an HP 2623 at home that you dial up on, but your office terminal is hardwired and known in /etc/ttytype.

Suppose you are accessing the system through a switching network that can connect any system to any incoming modem line in an arbitrary combination, making it nearly impossible to key on what port you are coming in on. Your office terminal is an HP 2622, and your home terminal is an HP 2623 running at 1200 baud on dial-up switch ports. Sometimes you use someone else's terminal at work, so you want it to verify what terminal type you have at high speeds, but at 1200 baud you are always on a 2623. Note the placement of the question mark and the quotes to protect the > and ? from interpretation by the shell.

All of the above entries fall back on the terminal type specified in /etc/ttytype if none of the conditions hold. The following entry is appropriate if you always dial up, always at the same baud rate, on many different kinds of terminals. Your most common terminal is an HP 2622. It always asks you what kind of terminal you are on, defaulting to 2622.

If the file /etc/ttytype is not properly installed and you want to key entirely on the baud rate, the following can be used:

AUTHOR

tset was developed by the University of California, Berkeley.

FILES

SEE ALSO

csh(1), sh(1), stty(1), ttytype(4), environ(5).