.\" authorization. *
.\"***************************************************************************
.\"
-.\" $Id: tset.1,v 1.75 2023/11/25 14:32:36 tom Exp $
-.TH @TSET@ 1 2023-11-25 "ncurses 6.4" "User commands"
+.\" $Id: tset.1,v 1.77 2023/12/02 20:52:24 tom Exp $
+.TH @TSET@ 1 2023-12-02 "ncurses 6.4" "User commands"
.ie \n(.g \{\
.ds `` \(lq
.ds '' \(rq
.PP
1. The \fBterminal\fP argument specified on the command line.
.PP
-2. The value of the \fBTERM\fP environmental variable.
+2. The value of the \fITERM\fP environmental variable.
.PP
3. (BSD systems only.) The terminal type associated with the standard
error output device in the \fI/etc/ttys\fP file.
-(On System\-V-like Unices and systems using that convention,
+(On System\ V hosts and systems using that convention,
\fBgetty\fP(1) does this job by setting
-\fBTERM\fP according to the type passed to it by \fI/etc/inittab\fP.)
+\fITERM\fP according to the type passed to it by \fI\%/etc/inittab\fP.)
.PP
4. The default terminal type, \*(``unknown\*('',
is not suitable for curses applications.
the terminal's window size.
.IP
If the window size cannot be obtained from the operating system,
-but the terminal description (or environment, e.g., \fBLINES\fP
-and \fBCOLUMNS\fP variables specify this),
+but the terminal description
+(or environment,
+e.g.,
+\fILINES\fP and \fI\%COLUMNS\fP variables specify this),
use this to set the operating system's notion of the window size.
.bP
if the \*(``\fB\-c\fP\*('' option is enabled,
.PP
When the \fB\-s\fP option is specified, the commands to enter the information
into the shell's environment are written to the standard output.
-If
-the \fBSHELL\fP environmental variable ends in \*(``csh\*('', the commands
+If the \fISHELL\fP environmental variable ends in \*(``csh\*('',
+the commands
are for \fBcsh\fP, otherwise, they are for \fBsh\fP(1).
Note, the \fBcsh\fP commands set and unset the shell variable
\fBnoglob\fP, leaving it unset.
.SS "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
-\fI/etc/ttys\fP file or the \fBTERM\fP environmental variable is often
+\fI/etc/ttys\fP file or the \fITERM\fP environmental variable is often
something generic like \fBnetwork\fP, \fBdialup\fP, or \fBunknown\fP.
When \fB@TSET@\fP is used in a startup script it is often desirable to
provide information about the type of terminal used on such ports.
.TP
.B \-s
Print the sequence of shell commands to initialize the environment variable
-\fBTERM\fP to the standard output;
+\fITERM\fP to the standard output;
see subsection \*(``Setting the Environment\*(''.
.TP
.B \-V
.SH ENVIRONMENT
The \fB@TSET@\fP command uses these environment variables:
.TP 5
-SHELL
-tells \fB@TSET@\fP whether to initialize \fBTERM\fP using \fBsh\fP(1) or
+.I SHELL
+tells \fB@TSET@\fP whether to initialize \fITERM\fP using \fBsh\fP(1) or
\fBcsh\fP(1) syntax.
.TP 5
-TERM
+.I TERM
Denotes your terminal type.
Each terminal type is distinct, though many are similar.
.TP 5
-TERMCAP
+.I TERMCAP
may denote the location of a termcap database.
If it is not an absolute pathname, e.g., begins with a \*(``/\*('',
\fB@TSET@\fP removes the variable from the environment before looking
for the terminal description.
.SH FILES
-.TP 5
-/etc/ttys
+.TP
+.I /etc/ttys
system port name to terminal type mapping database (BSD versions only).
.TP
.I \*d
In fact, the commonly-used \fBreset\fP utility
is always an alias for \fBtset\fP.
.PP
-The \fB@TSET@\fP utility provides for backward-compatibility with BSD
-environments (under most modern Unices, \fB/etc/inittab\fP and \fBgetty\fP(1)
-can set \fBTERM\fP appropriately for each dial-up line; this obviates what was
-\fB@TSET@\fP's most important use).
-This implementation behaves like 4.4BSD
-\fBtset\fP, with a few exceptions specified here.
+The \fB\%@TSET@\fP utility provides backward compatibility with BSD
+environments;
+under most modern Unices,
+\fI\%/etc/inittab\fP and \fBgetty\fP(1) can set \fITERM\fP appropriately
+for each dial-up line,
+obviating what was \fB\%@TSET@\fP's most important use.
+This implementation behaves like 4.4BSD \fBtset\fP,
+with a few exceptions we shall consider now.
.PP
A few options are different
-because the \fBTERMCAP\fP variable
+because the \fI\%TERMCAP\fP variable
is no longer supported under terminfo-based \fBncurses\fP:
.bP
The \fB\-S\fP option of BSD \fBtset\fP no longer works;
it prints an error message to the standard error and dies.
.bP
-The \fB\-s\fP option only sets \fBTERM\fP, not \fBTERMCAP\fP.
+The \fB\-s\fP option only sets \fITERM\fP,
+not \fI\%TERMCAP\fP.
.PP
There was an undocumented 4.4BSD feature
that invoking \fBtset\fP via a link named
In ncurses, \fB@TSET@\fP obtains the window size using
\fBsetupterm\fP, which may be from
the operating system,
-the \fBLINES\fP and \fBCOLUMNS\fP environment variables or
+the \fILINES\fP and \fICOLUMNS\fP environment variables or
the terminal description.
.PP
Obtaining the window size from the terminal description is common to
Generally speaking, a window size would be unset only if there were
some problem obtaining the value from the operating system
(and \fBsetupterm\fP would still fail).
-For that reason, the \fBLINES\fP and \fBCOLUMNS\fP environment variables
+For that reason,
+the \fILINES\fP and \fI\%COLUMNS\fP 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.
projects / ncurses.git / blobdiff