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Diffstat (limited to 'upstream/opensuse-leap-15-6/man1/clear.1')
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diff --git a/upstream/opensuse-leap-15-6/man1/clear.1 b/upstream/opensuse-leap-15-6/man1/clear.1 new file mode 100644 index 00000000..07cd11af --- /dev/null +++ b/upstream/opensuse-leap-15-6/man1/clear.1 @@ -0,0 +1,159 @@ +.\"*************************************************************************** +.\" Copyright (c) 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 * +.\" "Software"), to deal in the Software without restriction, including * +.\" without limitation the rights to use, copy, modify, merge, publish, * +.\" distribute, distribute with modifications, sublicense, and/or sell * +.\" copies of the Software, and to permit persons to whom the Software is * +.\" furnished to do so, subject to the following conditions: * +.\" * +.\" The above copyright notice and this permission notice shall be included * +.\" in all copies or substantial portions of the Software. * +.\" * +.\" THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS * +.\" OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * +.\" MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. * +.\" IN NO EVENT SHALL THE ABOVE COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, * +.\" DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR * +.\" OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR * +.\" THE USE OR OTHER DEALINGS IN THE SOFTWARE. * +.\" * +.\" Except as contained in this notice, the name(s) of the above copyright * +.\" holders shall not be used in advertising or otherwise to promote the * +.\" sale, use or other dealings in this Software without prior written * +.\" authorization. * +.\"*************************************************************************** +.\" +.\" $Id: clear.1,v 1.19 2017/11/18 23:51:59 tom Exp $ +.TH clear 1 "" +.\" these would be fallbacks for DS/DE, +.\" but groff changed the meaning of the macros. +.de NS +.ie n .sp +.el .sp .5 +.ie n .in +4 +.el .in +2 +.nf +.ft C \" Courier +.. +.de NE +.fi +.ft R +.in -4 +.. +.ie \n(.g .ds `` \(lq +.el .ds `` `` +.ie \n(.g .ds '' \(rq +.el .ds '' '' +.de bP +.ie n .IP \(bu 4 +.el .IP \(bu 2 +.. +.ds n 5 +.SH NAME +\fBclear\fR \- clear the terminal screen +.SH SYNOPSIS +\fBclear\fR [\fB\-T\fR\fItype\fR] [\fB\-V\fP] [\fB\-x\fP] +.br +.SH DESCRIPTION +\fBclear\fR clears your screen if this is possible, +including its scrollback buffer (if the extended \*(``E3\*('' capability is defined). +\fBclear\fR looks in the environment for the terminal type +given by the environment variable \fBTERM\fP, +and then in the +\fBterminfo\fR database to determine how to clear the screen. +.PP +\fBclear\fR writes to the standard output. +You can redirect the standard output to a file (which prevents +\fBclear\fR from actually clearing the screen), +and later \fBcat\fP the file to the screen, clearing it at that point. +.SH OPTIONS +.PP +.TP 5 +.B \-T \fItype\fP +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 +.B \-V +reports the version of ncurses which was used in this program, and exits. +The options are as follows: +.TP +.B \-x +do not attempt to clear the terminal's scrollback buffer +using the extended \*(``E3\*('' capability. +.SH HISTORY +A \fBclear\fP command appeared in 2.79BSD dated February 24, 1979. +Later that was provided in Unix 8th edition (1985). +.PP +AT&T adapted a different BSD program (\fBtset\fP) to make +a new command (\fBtput\fP), +and used this to replace the \fBclear\fP command with a shell script +which calls \fBtput clear\fP, e.g., +.NS +/usr/bin/tput ${1:+-T$1} clear 2> /dev/null +exit +.NE +.PP +In 1989, when Keith Bostic revised the BSD \fBtput\fP command +to make it similar to the AT&T \fBtput\fP, +he added a shell script for the \fBclear\fP command: +.NS +exec tput clear +.NE +.PP +The remainder of the script in each case is a copyright notice. +.PP +The ncurses \fBclear\fP command began in 1995 by adapting the original +BSD \fBclear\fP command (with terminfo, of course). +.PP +The \fBE3\fP extension came later: +.bP +In June 1999, xterm provided an extension to the standard control +sequence for clearing the screen. +Rather than clearing just the visible part of the screen using +.NS +printf '\\033[2J' +.NE +.IP +one could clear the \fIscrollback\fP using +.NS +printf '\\033[\fB3\fPJ' +.NE +.IP +This is documented in \fIXTerm Control Sequences\fP as a feature originating +with xterm. +.bP +A few other terminal developers adopted the feature, e.g., PuTTY in 2006. +.bP +In April 2011, a Red Hat developer submitted a patch to the Linux +kernel, modifying its console driver to do the same thing. +The Linux change, part of the 3.0 release, did not mention xterm, +although it was cited in the Red Hat bug report (#683733) +which led to the change. +.bP +Again, a few other terminal developers adopted the feature. But the +next relevant step was a change to the \fBclear\fP program in 2013 +to incorporate this extension. +.bP +In 2013, the \fBE3\fP extension was overlooked in \fBtput\fP with +the \*(``clear\*('' parameter. +That was addressed in 2016 by reorganizing \fBtput\fP to share +its logic with \fBclear\fP and \fBtset\fP. +.SH PORTABILITY +Neither IEEE Std 1003.1/The Open Group Base Specifications Issue 7 +(POSIX.1-2008) nor X/Open Curses Issue 7 documents tset or reset. +.PP +The latter documents \fBtput\fP, which could be used to replace this utility +either via a shell script or by an alias (such as a symbolic link) to +run \fBtput\fP as \fBclear\fP. +.SH SEE ALSO +\fBtput\fR(1), \fBterminfo\fR(\*n) +.PP +This describes \fBncurses\fR +version 6.1 (patch 20180317). |