NAME
ttytype — terminal identification program
SYNOPSIS
ttytype
[-apsv]
[-t
type]
DESCRIPTION
ttytype
automatically identifies the current terminal type
by sending an identification request sequence to the terminal.
This method works for local, modem, and remote terminal connections,
as well as for the
hpterm
and
xterm
terminal emulators.
Once the terminal has been identified,
ttytype
prints the terminal's type to the standard output (see
terminfo(4)).
This string is usually used as the value for the
TERM
environment variable.
If
ttytype
is unable to determine the correct terminal type,
it prompts the user for the correct terminal identification string.
Options
ttytype
recognizes the following options:
- -a
Causes
ttytype
to return an
ID
of "unknown" instead of prompting for the terminal type
if auto-identification fails.
If this option is not present,
ttytype
interactively prompts the user for the terminal type
if it is unable to determine the correct type automatically.
- -p
Causes
ttytype
to prompt for the terminal type before it sends the
terminal identification request sequence.
If the user responds with only a carriage return,
ttytype
proceeds with the automatic terminal identification process.
Any other response is taken as the correct terminal type.
Note that the
LINES
and
COLUMNS
variables are not set if the user manually enters a terminal type.
The
-p
option is normally used only for terminals
that do not behave well when presented with
ttytype's
terminal identification request sequence.
It gives the user a chance to respond
with the correct terminal type
before any escape sequences are sent that
could have an adverse effect on the terminal.
The
-a
option can be used in conjunction with the
-p
option.
The
-a
option only inhibits interactive prompting after
ttytype
has failed to identify the terminal by other means.
- -s
Tells
ttytype
to print a series of shell commands to set the
TERM,
LINES,
and
COLUMNS
environment variables to appropriate values.
In addition, the variable
ERASE
is set to the two-character sequence
representing the appropriate erase character for the terminal
(DEL for ANSI terminals, backspace for all others).
This two-character sequence can then be used as an argument to
stty
or
tset
(see
stty(1)
and
tset(1)).
The
SHELL
environment variable is consulted to see which shell syntax
to use for setting the environment variables.
This output is normally used with a command of the form:
- -t type
ttytype
normally attempts identification of Wyse, ANSI and HP terminals.
The
-t
type
argument can be used to restrict the inquiry
to that required for terminals of the specified type.
The accepted types are
ansi,
hp,
and
wyse.
Multiple
-t
options can be specified.
- -v
Enable verbose messages to standard error.
Notes
Use of the
-s
option is highly recommended
because many terminals support variable-size displays.
This option provides the only means
for automatically configuring the user environment
in such a manner that applications
can handle these terminals correctly.
Note that
LINES
and
COLUMNS
are not set if the
-p
option is used and the user manually enters a terminal type.
The following steps are performed in the order indicated
when identifying a terminal:
- 1.
ttytype
tries the Wyse 30/50/60 id request sequence.
- 2.
ttytype
tries the standard ANSI ID request sequence.
If a response is received,
it is converted to a string according to an internal table.
- 3.
ttytype
tries the
HP
id request sequence.
- 4.
If none of the above steps succeed,
ttytype
prompts interactively for the correct terminal type unless the
-a
option has been given.
ttytype
may skip one or more of the first three steps,
depending on the presence of
-t
options.
The HP ID request sequence can switch some
ANSI terminals into an unexpected operating mode.
Recovery from such a condition sometimes
requires cycling power on the terminal.
To avoid this problem,
ttytype
always sends the
HP identification sequence last.
EXAMPLES
ttytype
is most commonly used as part of the login sequence.
The following shell script fragment can be used
during login shell initialization:
#
# If TERM is not set, see if our port is listed in /etc/ttytype.
# If /etc/ttytype doesn't have information for our port, run
# ttytype(1) to try to determine the type of terminal we have.
#
# To have ttytype(1) prompt for the terminal type before trying
# to automatically identify the terminal, add the "-p" option
# to the "ttytype -s" command below.
#
if [ -z "$TERM" -o "$TERM" = network ]; then
unset TERM
eval `tset -s -Q`
if [ -z "$TERM" -o "$TERM" = unknown ]; then
eval `ttytype -s`
tset -Q -e ${ERASE:-\^h} $TERM
fi
fi
WARNINGS
The terminal identification sequences sent by
ttytype
can cause unexpected behavior on terminals
other than the Wyse 30/50/60, standard ANSI or HP terminals.
If you have such terminals in your configuration, use the
-t
or
-p
options to prevent
ttytype
from sending sequences that cause unexpected behavior.
AUTHOR
ttytype
was developed by HP.
Printable version
