X-Git-Url: http://ncurses.scripts.mit.edu/?a=blobdiff_plain;f=doc%2Fhtml%2Fman%2Fclear.1.html;h=66563a0508aa4bfaa134cb96bc6e8edcec313be3;hb=d66080c21038ad4feb2e41a0c4e517d5b4a03ab2;hp=1af927041d0cf6febb20816fd7f4a1f039e25414;hpb=5606eb48618dde18a593793e2e5dafadf18d345b;p=ncurses.git diff --git a/doc/html/man/clear.1.html b/doc/html/man/clear.1.html index 1af92704..66563a05 100644 --- a/doc/html/man/clear.1.html +++ b/doc/html/man/clear.1.html @@ -1,6 +1,6 @@ @@ -34,7 +34,7 @@
- +-clear(1) clear(1) +clear(1) General Commands Manual clear(1) @@ -52,100 +52,114 @@
- clear + clear [-Ttype] [-V] [-x]
- clear clears your screen if this is possible, including - its scrollback buffer (if the extended "E3" capability is - defined). clear looks in the environment for the terminal - type and then in the terminfo database to determine how to - clear the screen. + clear clears your screen if this is possible, including its scrollback + buffer (if the extended "E3" capability is defined). clear looks in + the environment for the terminal type given by the environment variable + TERM, and then in the terminfo database to determine how to clear the + screen. - clear ignores any command-line parameters that may be - present. + clear writes to the standard output. You can redirect the standard + output to a file (which prevents clear from actually clearing the + screen), and later cat the file to the screen, clearing it at that + point. + + +
+ -T type + indicates the type of terminal. Normally this option is unneces- + sary, because the default is taken from the environment variable + TERM. If -T is specified, then the shell variables LINES and COL- + UMNS will also be ignored. + + -V reports the version of ncurses which was used in this program, and + exits. The options are as follows: + + -x do not attempt to clear the terminal's scrollback buffer using the + extended "E3" capability.
- A clear command appeared in 2.79BSD dated February 24, - 1979. Later that was provided in Unix 8th edition (1985). + A clear 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 (tset) to make a new command + (tput), and used this to replace the clear command with a shell script + which calls tput clear, e.g., - AT&T adapted a different BSD program (tset) to make a new - command (tput), and used this to replace the clear command - with a shell script which calls tput clear, e.g., /usr/bin/tput ${1:+-T$1} clear 2> /dev/null exit - In 1989, when Keith Bostic revised the BSD tput command to - make it similar to the AT&T tput, he added a shell script - for the clear command: + In 1989, when Keith Bostic revised the BSD tput command to make it sim- + ilar to the AT&T tput, he added a shell script for the clear command: + exec tput clear - The remainder of the script in each case is a copyright - notice. + The remainder of the script in each case is a copyright notice. - The ncurses clear command began in 1995 by adapting the - original BSD clear command (with terminfo, of course). + The ncurses clear command began in 1995 by adapting the original BSD + clear command (with terminfo, of course). The E3 extension came later: - o In June 1999, xterm provided an extension to the stan- - dard control sequence for clearing the screen. Rather - than clearing just the visible part of the screen - using + o 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 scrollback using + printf '\033[3J' - This is documented in XTerm Control Sequences as a - feature originating with xterm. + This is documented in XTerm Control Sequences as a feature origi- + nating with xterm. - o A few other terminal developers adopted the feature, - e.g., PuTTY in 2006. + o A few other terminal developers adopted the feature, e.g., PuTTY in + 2006. - o 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. + o 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. - o Again, a few other terminal developers adopted the - feature. But the next relevant step was a change to - the clear program in 2013 to incorporate this exten- - sion. + o Again, a few other terminal developers adopted the feature. But + the next relevant step was a change to the clear program in 2013 to + incorporate this extension. - o In 2013, the E3 extension was overlooked in tput with - the "clear" parameter. That was addressed in 2016 by - reorganizing tput to share its logic with clear and - tset. + o In 2013, the E3 extension was overlooked in tput with the "clear" + parameter. That was addressed in 2016 by reorganizing tput to + share its logic with clear and tset.
- Neither IEEE Std 1003.1/The Open Group Base Specifica- - tions Issue 7 (POSIX.1-2008) nor X/Open Curses Issue 7 - documents tset or reset. + 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 tput, which could be used to replace - this utility either via a shell script or by an alias - (such as a symbolic link) to run tput as clear. + The latter documents tput, which could be used to replace this utility + either via a shell script or by an alias (such as a symbolic link) to + run tput as clear.
tput(1), terminfo(5) - This describes ncurses version 6.0 (patch 20161119). + This describes ncurses version 6.1 (patch 20180127). - clear(1) + clear(1)