This program initializes terminals.
- First, tset retrieves the current terminal mode settings for your ter-
- minal. It does this by successively testing
+ First, tset retrieves the current terminal mode settings for your
+ terminal. It does this by successively testing
o the standard error,
@@ -82,40 +83,41 @@
3. (BSD systems only.) The terminal type associated with the standard
error output device in the /etc/ttys file. (On System-V-like UNIXes
- and systems using that convention, getty does this job by setting TERM
- according to the type passed to it by /etc/inittab.)
+ and systems using that convention, getty(1) does this job by setting
+ TERM according to the type passed to it by /etc/inittab.)
- 4. The default terminal type, "unknown".
+ 4. The default terminal type, "unknown", is not suitable for curses
+ applications.
- If the terminal type was not specified on the command-line, the -m
+ If the terminal type was not specified on the command-line, the -m
option mappings are then applied (see the section TERMINALTYPEMAPPING
- for more information). Then, if the terminal type begins with a ques-
- tion 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 deter-
- mined, the terminal description for the terminal is retrieved. If no
- terminal description is found for the type, the user is prompted for
+ 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 terminal description for the terminal is retrieved. If
+ no terminal description is found for the type, the user is prompted for
another terminal type.
Once the terminal description is retrieved,
- o if the "-w" option is enabled, tset may update the terminal's win-
- dow size.
+ o if the "-w" option is enabled, tset may update the terminal's
+ window size.
- If the window size cannot be obtained from the operating system,
- but the terminal description (or environment, e.g., LINES and COL-
- UMNS variables specify this), use this to set the operating sys-
- tem's notion of the window size.
+ If the window size cannot be obtained from the operating system,
+ but the terminal description (or environment, e.g., LINES and
+ COLUMNS variables specify this), use this to set the operating
+ system's notion of the window size.
- o if the "-c" option is enabled, the backspace, interrupt and line
+ o if the "-c" option is enabled, the backspace, interrupt and line
kill characters (among many other things) are set
- o unless the "-I" option is enabled, the terminal and tab initializa-
- tion strings are sent to the standard error output, and tset waits
- one second (in case a hardware reset was issued).
+ o unless the "-I" option is enabled, the terminal and tab
+ initialization strings are sent to the standard error output, and
+ tset waits one second (in case a hardware reset was issued).
- o Finally, if the erase, interrupt and line kill characters have
- changed, or are not set to their default values, their values are
+ o 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.
@@ -131,10 +133,10 @@
o resets any unset special characters to their default values
before doing the terminal initialization described above. Also, rather
- than using the terminal initialization strings, it uses the terminal
+ than using the terminal initialization strings, it uses the terminal
reset strings.
- The reset command is useful after a program dies leaving a terminal in
+ The reset command is useful after a program dies leaving a terminal in
an abnormal state:
o you may have to type
@@ -142,7 +144,7 @@
<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
+ to work, as carriage-return may no longer work in the abnormal
state.
o Also, the terminal will often not echo the command.
@@ -153,24 +155,28 @@
-c Set control characters and modes.
- -e Set the erase character to ch.
+ -ech
+ Set the erase character to ch.
- -I Do not send the terminal or tab initialization strings to the ter-
- minal.
+ -I Do not send the terminal or tab initialization strings to the
+ terminal.
- -i Set the interrupt character to ch.
+ -ich
+ Set the interrupt character to ch.
- -k Set the line kill character to ch.
+ -kch
+ Set the line kill character to ch.
- -m Specify a mapping from a port type to a terminal. See the section
+ -mmapping
+ Specify a mapping from a port type to a terminal. See the section
TERMINALTYPEMAPPING for more information.
- -Q Do not display any values for the erase, interrupt and line kill
- characters. Normally tset displays the values for control charac-
- ters which differ from the system's default values.
+ -Q Do not display any values for the erase, interrupt and line kill
+ characters. Normally tset displays the values for control
+ characters which differ from the system's default values.
- -q The terminal type is displayed to the standard output, and the
- terminal is not initialized in any way. The option "-" by itself
+ -q The terminal type is displayed to the standard output, and the
+ terminal is not initialized in any way. The option "-" by itself
is equivalent but archaic.
-r Print the terminal type to the standard error output.
@@ -182,35 +188,36 @@
-V reports the version of ncurses which was used in this program, and
exits.
- -w Resize the window to match the size deduced via setupterm(3x).
- Normally this has no effect, unless setupterm is not able to
+ -w Resize the window to match the size deduced via setupterm(3x).
+ Normally this has no effect, unless setupterm is not able to
detect the window size.
- 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
+ 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".
If neither -c or -w is given, both options are assumed.
- It is often desirable to enter the terminal type and information about
+ 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:
+ 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(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 ... `
- When the terminal is not hardwired into the system (or the current sys-
- tem information is incorrect) the terminal type derived from the
+ 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
@@ -223,18 +230,18 @@
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 opera-
- tor 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 con-
- trol terminal). The terminal type is a string.
-
- If the terminal type is not specified on the command line, the -m map-
- pings 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.
+ (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
@@ -253,32 +260,26 @@
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 exclama-
- tion marks ("!").
+ that csh users insert a backslash character ("\") before any
+ exclamation marks ("!").
- A reset command appeared in 2BSD (April 1979), written by Kurt Shoens.
+ A reset command appeared in 1BSD (March 1978), written by Kurt Shoens.
This program set the erase and kill characters to ^H (backspace) and @
respectively. Mark Horton improved that in 3BSD (October 1979), adding
- intr, quit, start/stop and eof characters as well as changing the pro-
- gram to avoid modifying any user settings.
-
- Later in 4.1BSD (December 1980), Mark Horton added a call to the tset
- program using the -I and -Q options, i.e., using that to improve the
- terminal modes. With those options, that version of reset did not use
- the termcap database.
+ intr, quit, start/stop and eof characters as well as changing the
+ program to avoid modifying any user settings. That version of reset
+ did not use the termcap database.
- A separate tset command was provided in 2BSD by Eric Allman. While the
- oldest published source (from 1979) provides both tset and reset, All-
- man's comments in the 2BSD source code indicate that he began work in
- October 1977, continuing development over the next few years.
+ A separate tset command was provided in 1BSD by Eric Allman, using the
+ termcap database. Allman's comments in the source code indicate that
+ he began work in October 1977, continuing development over the next few
+ years.
- In September 1980, Eric Allman modified tset, adding the code from the
- existing "reset" feature when tset was invoked as reset. Rather than
- simply copying the existing program, in this merged version, tset used
- the termcap database to do additional (re)initialization of the termi-
- nal. This version appeared in 4.1cBSD, late in 1982.
+ According to comments in the source code, the tset program was modified
+ in September 1980, to use logic copied from the 3BSD "reset" when it
+ was invoked as reset. This version appeared in 4.1cBSD, late in 1982.
Other developers (e.g., Keith Bostic and Jim Bloom) continued to modify
tset until 4.4BSD was released in 1993.
@@ -293,87 +294,89 @@
The AT&T tput utility (AIX, HPUX, Solaris) incorporated the terminal-
mode manipulation as well as termcap-based features such as resetting
- tabstops from tset in BSD (4.1c), presumably with the intention of mak-
- ing tset obsolete. However, each of those systems still provides tset.
- In fact, the commonly-used reset utility is always an alias for tset.
-
- The tset utility provides for backward-compatibility with BSD environ-
- ments (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.
-
- A few options are different because the TERMCAP variable is no longer
+ tabstops from tset in BSD (4.1c), presumably with the intention of
+ making tset obsolete. However, each of those systems still provides
+ tset. In fact, the commonly-used reset utility is always an alias for
+ tset.
+
+ The tset utility provides 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.
+
+ A few options are different because the TERMCAP variable is no longer
supported under terminfo-based ncurses:
- o The -S option of BSD tset no longer works; it prints an error mes-
- sage to the standard error and dies.
+ o The -S option of BSD tset no longer works; it prints an error
+ message to the standard error and dies.
o The -s option only sets TERM, not TERMCAP.
- 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 let-
- ter) set the terminal to use upper-case only. This feature has been
+ 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 docu-
- mented 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 -a, -d, and -p options
- are therefore omitted from the usage summary above.
-
- Very old systems, e.g., 3BSD, used a different terminal driver which
- was replaced in 4BSD in the early 1980s. To accommodate these older
- systems, the 4BSD tset provided a -n option to specify that the new
- terminal driver should be used. This implementation does not provide
+ 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 -a, -d, and
+ -p options are therefore omitted from the usage summary above.
+
+ Very old systems, e.g., 3BSD, used a different terminal driver which
+ was replaced in 4BSD in the early 1980s. To accommodate these older
+ systems, the 4BSD tset provided a -n option to specify that the new
+ terminal driver should be used. This implementation does not provide
that choice.
- It is still permissible to specify the -e, -i, and -k options without
+ 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.
+ As of 4.4BSD, 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 -c and -w options are not found in earlier implementations. How-
- ever, a different window size-change feature was provided in 4.4BSD.
+ The -c and -w options are not found in earlier implementations.
+ However, a different window size-change feature was provided in 4.4BSD.
- o In 4.4BSD, tset uses the window size from the termcap description
- to set the window size if tset is not able to obtain the window
+ o In 4.4BSD, tset uses the window size from the termcap description
+ to set the window size if tset is not able to obtain the window
size from the operating system.
o In ncurses, tset obtains the window size using setupterm, which may
- be from the operating system, the LINES and COLUMNS environment
+ be from the operating system, the LINES and COLUMNS environment
variables or the terminal description.
- Obtaining the window size from the terminal description is common to
- both implementations, but considered obsolescent. Its only practical
+ Obtaining the window size from the terminal description is common to
+ both implementations, but considered obsolescent. Its only practical
use is for hardware terminals. Generally speaking, a window size would
- be unset only if there were some problem obtaining the value from the
- operating system (and setupterm would still fail). For that reason,
- the LINES and COLUMNS environment variables may be useful for working
- around window-size problems. Those have the drawback that if the win-
- dow is resized, those variables must be recomputed and reassigned. To
- do this more easily, use the resize(1) program.
+ be unset only if there were some problem obtaining the value from the
+ operating system (and setupterm would still fail). For that reason,
+ the LINES and COLUMNS environment variables may be useful for working
+ around window-size problems. Those have the drawback that if the
+ window is resized, those variables must be recomputed and reassigned.
+ To do this more easily, use the resize(1) program.
The tset command uses these environment variables:
SHELL
- tells tset whether to initialize TERM using sh or csh syntax.
+ tells tset whether to initialize TERM using sh(1) or csh(1)
+ syntax.
TERM Denotes your terminal type. Each terminal type is distinct,
though many are similar.
TERMCAP
may denote the location of a termcap database. If it is not an
- absolute pathname, e.g., begins with a "/", tset removes the vari-
- able from the environment before looking for the terminal descrip-
- tion.
+ absolute pathname, e.g., begins with a "/", tset removes the
+ variable from the environment before looking for the terminal
+ description.