'\" t
.\"***************************************************************************
-.\" Copyright (c) 1998-2016,2017 Free Software Foundation, Inc. *
+.\" Copyright 2018,2020 Thomas E. Dickey *
+.\" Copyright 1998-2016,2017 Free Software Foundation, Inc. *
.\" *
.\" Permission is hereby granted, free of charge, to any person obtaining a *
.\" copy of this software and associated documentation files (the *
.\" authorization. *
.\"***************************************************************************
.\"
-.\" $Id: tput.1,v 1.52 2017/01/21 17:38:30 tom Exp $
+.\" $Id: tput.1,v 1.64 2020/04/25 21:52:49 tom Exp $
.TH @TPUT@ 1 ""
.ds d @TERMINFO@
.ds n 1
.ie \n(.g .ds '' \(rq
.el .ds '' ''
.de bP
-.IP \(bu 4
+.ie n .IP \(bu 4
+.el .IP \(bu 2
..
.SH NAME
\fB@TPUT@\fR, \fBreset\fR \- initialize a terminal or query terminfo database
.SH SYNOPSIS
\fB@TPUT@\fR [\fB\-T\fR\fItype\fR] \fIcapname\fR [\fIparameters\fR]
.br
-\fB@TPUT@\fR [\fB\-T\fR\fItype\fR] \fBclear\fR
+\fB@TPUT@\fR [\fB\-T\fR\fItype\fR] [\fB\-x\fP] \fBclear\fR
.br
\fB@TPUT@\fR [\fB\-T\fR\fItype\fR] \fBinit\fR
.br
and the \fIcapname\fR associated with each, see \fBterminfo\fR(5).
.SS Options
.TP
-\fB\-T\fR\fItype\fR
-indicates the \fItype\fR of terminal.
-Normally this option is
-unnecessary, because the default is taken from the environment
-variable \fBTERM\fR.
-If \fB\-T\fR is specified, then the shell
-variables \fBLINES\fR and \fBCOLUMNS\fR will also be ignored.
-.TP
\fB\-S\fR
allows more than one capability per invocation of \fB@TPUT@\fR. The
capabilities must be passed to \fB@TPUT@\fR from the standard input
meaning of the \fB0\fR and \fB1\fR boolean and string exit codes (see the
EXIT CODES section).
.IP
-Again, \fB@TPUT@\fR uses a table and the presence of parameters in its input
+Because some capabilities may use
+\fIstring\fP parameters rather than \fInumbers\fP,
+\fB@TPUT@\fR uses a table and the presence of parameters in its input
to decide whether to use \fBtparm\fR(3X),
and how to interpret the parameters.
.TP
+\fB\-T\fR\fItype\fR
+indicates the \fItype\fR of terminal.
+Normally this option is
+unnecessary, because the default is taken from the environment
+variable \fBTERM\fR.
+If \fB\-T\fR is specified, then the shell
+variables \fBLINES\fR and \fBCOLUMNS\fR will also be ignored.
+.TP
\fB\-V\fR
reports the version of ncurses which was used in this program, and exits.
+.TP
+.B \-x
+do not attempt to clear the terminal's scrollback buffer
+using the extended \*(``E3\*('' capability.
.SS Commands
+A few commands (\fBinit\fP, \fBreset\fP and \fBlongname\fP) are
+special; they are defined by the \fB@TPUT@\fP program.
+The others are the names of \fIcapabilities\fP from the terminal database
+(see \fBterminfo\fR(5) for a list).
+Although \fBinit\fP and \fBreset\fP resemble capability names,
+\fB@TPUT@\fP uses several capabilities to perform these special functions.
.TP
\fIcapname\fR
indicates the capability from the terminal database.
.bP
standard input and
.bP
-ultimately \*(lq/dev/tty\*(rq
+ultimately \*(``/dev/tty\*(''
.RE
.IP
to obtain terminal settings.
\fBlongname\fR
If the terminal database is present and an entry for the
user's terminal exists (see \fB\-T\fR\fItype\fR above), then the long name
-of the terminal will be put out. The long name is the last
+of the terminal will be put out.
+The long name is the last
name in the first line of the terminal's description in the
\fBterminfo\fR database [see \fBterm\fR(5)].
.SS Aliases
(not done with \fB@TPUT@\fP).
.bP
On the other hand, \fB@TSET@\fP's repertoire of terminal capabilities for
-resetting the terminal was more limited, i.e., only \fBreset_1string\fP, \fBreset_2string\fP and \fBreset_file\fP
+resetting the terminal was more limited,
+i.e., only \fBreset_1string\fP, \fBreset_2string\fP and \fBreset_file\fP
in contrast to the tab-stops and margins which are set by this utility.
.bP
The \fBreset\fP program is usually an alias for \fB@TSET@\fP,
because of this difference with resetting terminal modes and special characters.
.PP
With the changes made for ncurses 6.1, the \fIreset\fP feature of the
-two programs is (mostly) the same. A few differences remain:
+two programs is (mostly) the same.
+A few differences remain:
.bP
The \fB@TSET@\fP program waits one second when resetting,
in case it happens to be a hardware terminal.
.bP
The two programs write the terminal initialization strings
-to different streams (i.e.,. the standard error for \fB@TSET@\fP and the
+to different streams (i.e., the standard error for \fB@TSET@\fP and the
standard output for \fB@TPUT@\fP).
.IP
\fBNote:\fP although these programs write to different streams,
same effect as \fB@TPUT@ init\fR.
Again, you are less likely to use that link because another program
named \fBinit\fP has a more well-established use.
+.SS Terminal Size
+.PP
+Besides the special commands (e.g., \fBclear\fP),
+@TPUT@ treats certain terminfo capabilities specially:
+\fBlines\fP and \fBcols\fP.
+@TPUT@ calls \fBsetupterm\fP(3X) to obtain the terminal size:
+.bP
+first, it gets the size from the terminal database
+(which generally is not provided for terminal emulators
+which do not have a fixed window size)
+.bP
+then it asks the operating system for the terminal's size
+(which generally works, unless connecting via a serial line which
+does not support \fINAWS\fP: negotiations about window size).
+.bP
+finally, it inspects the environment variables \fBLINES\fP and \fBCOLUMNS\fP
+which may override the terminal size.
+.PP
+If the \fB\-T\fP option is given
+@TPUT@ ignores the environment variables by calling \fBuse_tioctl(TRUE)\fP,
+relying upon the operating system (or finally, the terminal database).
.SH EXAMPLES
.TP 5
\fB@TPUT@ init\fR
.TP 5
\fB@TPUT@ cup 0 0\fR
Send the sequence to move the cursor to row \fB0\fR, column \fB0\fR
-(the upper left corner of the screen, usually known as the \*(lqhome\*(rq
+(the upper left corner of the screen, usually known as the \*(``home\*(''
cursor position).
.TP 5
\fB@TPUT@ clear\fR
\fBbold=`@TPUT@ smso` offbold=`@TPUT@ rmso`\fR
Set the shell variables \fBbold\fR, to begin stand-out mode
sequence, and \fBoffbold\fR, to end standout mode sequence,
-for the current terminal. This might be followed by a
+for the current terminal.
+This might be followed by a
prompt: \fBecho "${bold}Please type in your name: ${offbold}\\c"\fR
.TP 5
\fB@TPUT@ hc\fR
.RE
.TP 5
\&
-This example shows \fB@TPUT@\fR processing several capabilities in one invocation.
+This example shows \fB@TPUT@\fR processing several capabilities
+in one invocation.
It clears the screen,
moves the cursor to position 10, 10
and turns on bold (extra bright) mode.
number of lines with errors.
If no errors are found, the exit code is \fB0\fR.
No indication of which line failed can be given so
-exit code \fB1\fR will never appear. Exit codes \fB2\fR, \fB3\fR, and
+exit code \fB1\fR will never appear.
+Exit codes \fB2\fR, \fB3\fR, and
\fB4\fR retain their usual interpretation.
If the \fB\-S\fR option is not used,
the exit code depends on the type of \fIcapname\fR:
(more than half the program) were incorporated from
the \fBreset\fP feature of BSD \fBtset\fP written by Eric Allman.
.PP
-Keith Bostic replaced the BSD \fBtput\fP command in 1989 with a new implementation
+Keith Bostic replaced the BSD \fBtput\fP command in 1989
+with a new implementation
based on the AT&T System V program \fBtput\fP.
Like the AT&T program, Bostic's version
accepted some parameters named for \fIterminfo capabilities\fP
Also, Bostic's BSD \fBtput\fP did not modify the terminal I/O modes
as the earlier BSD \fBtset\fP had done.
.PP
-At the same time, Bostic added a shell script named \*(lqclear\*(rq,
+At the same time, Bostic added a shell script named \*(``clear\*('',
which used \fBtput\fP to clear the screen.
.PP
Both of these appeared in 4.4BSD,
-becoming the \*(lqmodern\*(rq BSD implementation of \fBtput\fP.
+becoming the \*(``modern\*('' BSD implementation of \fBtput\fP.
+.PP
+This implementation of \fBtput\fP began from a different source than
+AT&T or BSD: Ross Ridge's \fImytinfo\fP package, published on
+\fIcomp.sources.unix\fP in December 1992.
+Ridge's program made more sophisticated use of the terminal capabilities
+than the BSD program.
+Eric Raymond used that \fBtput\fP program
+(and other parts of \fImytinfo\fP) in ncurses in June 1995.
+Using the portions dealing with terminal capabilities
+almost without change,
+Raymond made improvements to the way the command-line parameters
+were handled.
.SH PORTABILITY
.PP
This implementation of \fBtput\fP differs from AT&T \fBtput\fP in
The AT&T implementation's \fBinit\fP and \fBreset\fP commands
use the BSD (4.1c) \fBtset\fP source, which manipulates terminal modes.
It successively tries standard output, standard error, standard input
-before falling back to \*(lq/dev/tty\*(rq and finally just assumes
+before falling back to \*(``/dev/tty\*('' and finally just assumes
a 1200Bd terminal.
When updating terminal modes, it ignores errors.
.IP
-Until changes made after ncurses 6.0, \fB@TPUT@\fP did not modify terminal modes.
+Until changes made after ncurses 6.0,
+\fB@TPUT@\fP did not modify terminal modes.
\fB@TPUT@\fP now uses a similar scheme,
using functions shared with \fB@TSET@\fP
(and ultimately based on the 4.4BSD \fBtset\fP).
X/Open Curses Issue 7 documents \fBtput\fP differently, with \fIcapname\fP
and the other features used in this implementation.
.bP
-That is, there are two standards for \fBtput\fP: POSIX (a subset) and X/Open Curses (the full implementation).
+That is, there are two standards for \fBtput\fP:
+POSIX (a subset) and X/Open Curses (the full implementation).
POSIX documents a subset to avoid the complication of including X/Open Curses
and the terminal capabilities database.
.bP
-While it is certainly possible to write a \fBtput\fP program without using curses,
+While it is certainly possible to write a \fBtput\fP program
+without using curses,
none of the systems which have a curses implementation provide
a \fBtput\fP utility which does not provide the \fIcapname\fP feature.
+.PP
+X/Open Curses Issue 7 (2009) is the first version to document utilities.
+However that part of X/Open Curses does not follow existing practice
+(i.e., Unix features documented in SVID 3):
+.bP
+It assigns exit code 4 to \*(``invalid operand\*('',
+which may be the same as \fIunknown capability\fP.
+For instance, the source code for Solaris' xcurses uses the term
+\*(``invalid\*('' in this case.
+.bP
+It assigns exit code 255 to a numeric variable that is not specified in
+the terminfo database.
+That likely is a documentation error,
+confusing the \fB\-1\fP written to the standard output for an absent
+or cancelled numeric value versus an (unsigned) exit code.
+.PP
+The various Unix systems (AIX, HPUX, Solaris) use the same exit-codes
+as ncurses.
+.PP
+NetBSD curses documents different exit codes which do not correspond
+to either ncurses or X/Open.
.SH SEE ALSO
\fB@CLEAR@\fR(\*n),
\fBstty\fR(1),
projects / ncurses.git / blobdiff