diff options
Diffstat (limited to 'doc/html/man/clear.1.html')
-rw-r--r-- | doc/html/man/clear.1.html | 143 |
1 files changed, 115 insertions, 28 deletions
diff --git a/doc/html/man/clear.1.html b/doc/html/man/clear.1.html index e642e6b..93455b4 100644 --- a/doc/html/man/clear.1.html +++ b/doc/html/man/clear.1.html @@ -1,7 +1,7 @@ -<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN"> <!-- **************************************************************************** - * Copyright (c) 1998-2010,2013 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 * @@ -27,57 +27,144 @@ * sale, use or other dealings in this Software without prior written * * authorization. * **************************************************************************** - * @Id: clear.1,v 1.10 2013/06/22 22:22:11 tom Exp @ + * @Id: clear.1,v 1.23 2020/02/02 23:34:34 tom Exp @ + * these would be fallbacks for DS/DE, + * but groff changed the meaning of the macros. --> +<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01//EN"> <HTML> <HEAD> +<meta http-equiv="Content-Type" content="text/html; charset=us-ascii"> +<meta name="generator" content="Manpage converted by man2html - see https://invisible-island.net/scripts/readme.html#others_scripts"> <TITLE>clear 1</TITLE> -<link rev=made href="mailto:bug-ncurses@gnu.org"> +<link rel="author" href="mailto:bug-ncurses@gnu.org"> <meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1"> </HEAD> <BODY> -<H1>clear 1</H1> -<HR> +<H1 class="no-header">clear 1</H1> <PRE> -<!-- Manpage converted by man2html 3.0.1 --> -<STRONG><A HREF="clear.1.html">clear(1)</A></STRONG> <STRONG><A HREF="clear.1.html">clear(1)</A></STRONG> +<STRONG><A HREF="clear.1.html">clear(1)</A></STRONG> General Commands Manual <STRONG><A HREF="clear.1.html">clear(1)</A></STRONG> -</PRE> -<H2>NAME</H2><PRE> +</PRE><H2><a name="h2-NAME">NAME</a></H2><PRE> <STRONG>clear</STRONG> - clear the terminal screen -</PRE> -<H2>SYNOPSIS</H2><PRE> - <STRONG>clear</STRONG> +</PRE><H2><a name="h2-SYNOPSIS">SYNOPSIS</a></H2><PRE> + <STRONG>clear</STRONG> [<STRONG>-T</STRONG><EM>type</EM>] [<STRONG>-V</STRONG>] [<STRONG>-x</STRONG>] -</PRE> -<H2>DESCRIPTION</H2><PRE> - <STRONG>clear</STRONG> clears your screen if this is possible, including - its scrollback buffer (if the extended "E3" capability is - defined). <STRONG>clear</STRONG> looks in the environment for the terminal - type and then in the <STRONG>terminfo</STRONG> database to determine how to - clear the screen. +</PRE><H2><a name="h2-DESCRIPTION">DESCRIPTION</a></H2><PRE> + <STRONG>clear</STRONG> clears your screen if this is possible, including its scrollback + buffer (if the extended "E3" capability is defined). <STRONG>clear</STRONG> looks in + the environment for the terminal type given by the environment variable + <STRONG>TERM</STRONG>, and then in the <STRONG>terminfo</STRONG> database to determine how to clear the + screen. - <STRONG>clear</STRONG> ignores any command-line parameters that may be - present. + <STRONG>clear</STRONG> writes to the standard output. You can redirect the standard + output to a file (which prevents <STRONG>clear</STRONG> from actually clearing the + screen), and later <STRONG>cat</STRONG> the file to the screen, clearing it at that + point. -</PRE> -<H2>SEE ALSO</H2><PRE> +</PRE><H2><a name="h2-OPTIONS">OPTIONS</a></H2><PRE> + <STRONG>-T</STRONG> <EM>type</EM> + indicates the <EM>type</EM> of terminal. Normally this option is unneces- + sary, because the default is taken from the environment variable + <STRONG>TERM</STRONG>. If <STRONG>-T</STRONG> is specified, then the shell variables <STRONG>LINES</STRONG> and <STRONG>COL-</STRONG> + <STRONG>UMNS</STRONG> will also be ignored. + + <STRONG>-V</STRONG> reports the version of ncurses which was used in this program, and + exits. The options are as follows: + + <STRONG>-x</STRONG> do not attempt to clear the terminal's scrollback buffer using the + extended "E3" capability. + + +</PRE><H2><a name="h2-HISTORY">HISTORY</a></H2><PRE> + A <STRONG>clear</STRONG> command appeared in 2.79BSD dated February 24, 1979. Later + that was provided in Unix 8th edition (1985). + + AT&T adapted a different BSD program (<STRONG>tset</STRONG>) to make a new command + (<STRONG>tput</STRONG>), and used this to replace the <STRONG>clear</STRONG> command with a shell script + which calls <STRONG>tput</STRONG> <STRONG>clear</STRONG>, e.g., + + /usr/bin/tput ${1:+-T$1} clear 2> /dev/null + exit + + In 1989, when Keith Bostic revised the BSD <STRONG>tput</STRONG> command to make it sim- + ilar to the AT&T <STRONG>tput</STRONG>, he added a shell script for the <STRONG>clear</STRONG> command: + + exec tput clear + + The remainder of the script in each case is a copyright notice. + + The ncurses <STRONG>clear</STRONG> command began in 1995 by adapting the original BSD + <STRONG>clear</STRONG> command (with terminfo, of course). + + The <STRONG>E3</STRONG> extension came later: + + <STRONG>o</STRONG> 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 + + printf '\033[2J' + + one could clear the <EM>scrollback</EM> using + + printf '\033[<STRONG>3</STRONG>J' + + This is documented in <EM>XTerm</EM> <EM>Control</EM> <EM>Sequences</EM> as a feature origi- + nating with xterm. + + <STRONG>o</STRONG> A few other terminal developers adopted the feature, e.g., PuTTY in + 2006. + + <STRONG>o</STRONG> 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. + + <STRONG>o</STRONG> Again, a few other terminal developers adopted the feature. But + the next relevant step was a change to the <STRONG>clear</STRONG> program in 2013 to + incorporate this extension. + + <STRONG>o</STRONG> In 2013, the <STRONG>E3</STRONG> extension was overlooked in <STRONG>tput</STRONG> with the "clear" + parameter. That was addressed in 2016 by reorganizing <STRONG>tput</STRONG> to + share its logic with <STRONG>clear</STRONG> and <STRONG>tset</STRONG>. + + +</PRE><H2><a name="h2-PORTABILITY">PORTABILITY</a></H2><PRE> + 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. + + The latter documents <STRONG>tput</STRONG>, which could be used to replace this utility + either via a shell script or by an alias (such as a symbolic link) to + run <STRONG>tput</STRONG> as <STRONG>clear</STRONG>. + + +</PRE><H2><a name="h2-SEE-ALSO">SEE ALSO</a></H2><PRE> <STRONG><A HREF="tput.1.html">tput(1)</A></STRONG>, <STRONG><A HREF="terminfo.5.html">terminfo(5)</A></STRONG> - This describes <STRONG>ncurses</STRONG> version 5.9 (patch 20141220). + This describes <STRONG>ncurses</STRONG> version 6.2 (patch 20200212). - <STRONG><A HREF="clear.1.html">clear(1)</A></STRONG> + <STRONG><A HREF="clear.1.html">clear(1)</A></STRONG> </PRE> -<HR> -Man(1) output converted with <a href="http://invisible-island.net/scripts/readme.html#others_scripts">man2html</a> +<div class="nav"> +<ul> +<li><a href="#h2-NAME">NAME</a></li> +<li><a href="#h2-SYNOPSIS">SYNOPSIS</a></li> +<li><a href="#h2-DESCRIPTION">DESCRIPTION</a></li> +<li><a href="#h2-OPTIONS">OPTIONS</a></li> +<li><a href="#h2-HISTORY">HISTORY</a></li> +<li><a href="#h2-PORTABILITY">PORTABILITY</a></li> +<li><a href="#h2-SEE-ALSO">SEE ALSO</a></li> +</ul> +</div> </BODY> </HTML> |