\input texinfo @c -*-texinfo-*- @c %**start of header @setfilename adjbacklight.info @settitle adjbacklight @afourpaper @documentencoding UTF-8 @documentlanguage en @finalout @c %**end of header @c @defindex op @c @synindex op vr @c @synindex cp pg @copying This manual is for @command{adjbacklight}. Copyright @copyright{} 2013, 2014 Mattias Andrée (maandree@@member.fsf.org) @quotation Permission is granted to copy, distribute and/or modify this document under the terms of the GNU Free Documentation License, Version 1.3 or any later version published by the Free Software Foundation; with no Invariant Sections, with no Front-Cover Texts, and with no Back-Cover Texts. A copy of the license is included in the section entitled ``GNU Free Documentation License''. @end quotation @end copying @ifnottex @node Top @top adjbacklight @insertcopying @end ifnottex @titlepage @title adjbacklight 5 @subtitle Convient method for adjusting the backlight on your portable computer. @author Mattias Andrée, maandree@@member.fsf.org @page @vskip 0pt plus 1filll @insertcopying @page @*@* @center And sometimes the portable computers' adjustment keys arn't even wired to the hardware… @end titlepage @contents @menu * Overview:: Overview of @command{adjbacklight} * Invoking:: How to start @command{adjbacklight} * Using:: How to use @command{adjbacklight} * Behind the scenes:: How @command{adjbacklight} works * License of adjbacklight:: Summary of the license of the program * GNU General Public License:: The license of the program * GNU Free Documentation License:: The license of this manual * Concept index:: Concept index @end menu @node Overview @chapter Overview @cindex overview @cindex description @command{adjbacklight} is convient method for adjusting the backlight on your portable computer. Depending on your computer, the details of @command{adjbacklight} differs. For some computers program will adjust the same parameters as the keys on your keyboard, one other computers this program will adjust an independent parameter allowing more detailed adjustment and may not be affected by the battery status change. One some computers the keys for the suns does not do anything and is expected to be binded by the OS, for thoses computers this may be the best choice if you are in the TTY. @command{adjbacklight} allows 0.5 % precision, assuming that the firmware allows at least that. If you want higher precision, it is simple to modify the source code. Just run @code{sed -i s/200/400/g src/adjbacklight.c}, if you want 0.25 % precision. @node Invoking @chapter Invoking @cindex invoking @cindex starting @cindex options @cindex arguments @cindex device @cindex selecting device @cindex @command{adjbacklight} @cindex @option{-c} @cindex @option{--copying} @cindex @option{--copyright} @cindex @option{-w} @cindex @option{--warranty} @cindex @option{-a} @cindex @option{--all} @command{adjbacklight} can be started with @option{-c}, @option{--copying} or @option{--copyright} for displaying copyright information, @option{-w} or @option{--warranty} for displaying a warranty disclaimer. If any other options is used, help information is displayed. To actually use the program, just execute @command{adjbacklight} without any arguments, or with @option{-a} or @option{--all} to not limit the devices to those that are not ACPI video devices. Alternatively you can list the devices either by full path or just the name in the directory @file{/sys/class/backlight}. @node Using @chapter Using @cindex usage @cindex keyboard @cindex darken screen @cindex brighten screen @cindex quit @cindex exit @cindex close @cindex next screen @cindex password @cindex @command{sudo} These key commands work when you start @command{adjbacklight} without arguments and can see a bar. Due to restricted write permissions in @file{/sys} you are required to enter your password and need to be a sudoer; if you do not want this you could make your init sequence give you write permissions to @file{/sys/class/backlight/*/brightness}, and just remove the @command{sudo} in the bash script @file{adjbacklight}. The @kbd{left} and @kbd{down} arrow keys are used to darken the screen. The @kbd{right} and @kbd{up} arrow keys are used to brighten the screen. @kbd{q}, @kbd{enter} and @kbd{d} continues to the next backlight controller, or if you are at the last one, quits the program. @node Behind the scenes @chapter Behind the scenes @cindex behind the scenes @cindex inner workings On normally configured Linux systems, the kernel mounts a virtual partition on @file{/sys}. If you have screens using backlight, you should find backlight device in @file{/sys/class/backlight}. These devices are directories containing control files which you can read the current values from or write to (perhaps using @command{echo}) to modify the value. In a directory in @file{/sys/class/backlight} you will find @file{brightness} and @file{max_brightness}. Just read from @file{max_brightness} to get the maximum allowed integer value in @file{brightness}, the minimum value is 0. @node License of adjbacklight @appendix License of adjbacklight @flushleft adjbacklight – Convient method for adjusting the backlight on your portable computer Copyright © 2012, 2013, 2014 Mattias Andrée (maandree@@member.fsf.org) This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with this program. If not, see . @end flushleft @node GNU General Public License @appendix GNU General Public License @include gpl.texinfo @node GNU Free Documentation License @appendix GNU Free Documentation License @include fdl.texinfo @node Concept index @appendix Concept index @printindex cp @c @node Concept and program index @c @appendix Concept and program index @c @printindex pg @c @node Variable and option index @c @appendix Variable and option index @c @printindex vr @bye