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diff --git a/doc/info/adjbacklight.texinfo b/doc/info/adjbacklight.texinfo new file mode 100644 index 0000000..b4c6986 --- /dev/null +++ b/doc/info/adjbacklight.texinfo @@ -0,0 +1,245 @@ +\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 7.1 +@subtitle Convenient 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. + +@cindex root +@cindex video +@cindex permissions +To use @command{adjbacklight} you must either be root or be a member of the +group `video'. The `video' membership requirement is artificial so you can rip +that out from the code if you prefer, but the effective user must be `root' +(EUID = 0) otherwise you will not have permission to use files in +@file{/sys/class/backlight} unless you make your initialisation +system give you access. + + + +@node Invoking +@chapter Invoking +@cindex invoking +@cindex starting +@cindex options +@cindex arguments +@cindex device +@cindex selecting device +@cindex interactive mode +@cindex non-interactive mode +@cindex @command{adjbacklight} +@cindex @option{-c} +@cindex @option{--copying} +@cindex @option{--copyright} +@cindex @option{-w} +@cindex @option{--warranty} +@cindex @option{-a} +@cindex @option{--all} +@cindex @option{-g} +@cindex @option{--get} +@cindex @option{-s} +@cindex @option{--set} + +@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. + +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}. + +If you do not want to run in interactive mode, you can use the option +@option{-g} or @option{--get} to get the average backlight of all devices +selected by the arguments (as in interactive mode), the value will be +printed percents with no whitespace between the value and the percent, +the value will be formated in the traditional computer format, only 0-9 +with one dot (.) for separation of the integer part and the decimal part +(which will be two digits.) If you want to set the backlight there are +a few ways to do this: @option{-s} or @option{--set} followed by a value +or the value directly but with a prepending `=' if it does not start with +`+' or `-'. This argument is formated similar to the value printed by +@option{--get}, except it may end with zero, one, or two percent signed. +`+' is used for increase in brightness, `-' for decrease. Zero percent +signed is used for a raw value, one percent signed is used for a cooked +value that is usable on all backlight devices, and two percent signed +is used for a value relative to the current value. + +Assume the current backlight is 50 (25 %) on a device and the maximum is +200. @code{+25} will set it to 75 (37,5 %) and @code{-25} will set it to +25 (12,5 %). @code{+50%} will set it to 75 % (150), @code{-50%} would +set it to -25 % (-50) but because that is not within the accepted value +range it will be truncated to 0. @code{+100%%} will set it to 100 (50 %), +that it 200 % of the current brightness, @code{-50%%} will set it to +25 (12,5 %), that is 50 % of the current brightness. For the following +formats the `=' is optional if @option{-s} or @option{--set} is used. +@code{=150} will set the brightness to 150 (75 %), @code{=50%} will set +it to 50 % (100), and @code{=200%%} will set it to 100 (50 %), that is +200 % of the current brightness. + + + +@node Using +@chapter Using +@cindex interactive mode +@cindex usage +@cindex keyboard +@cindex darken screen +@cindex brighten screen +@cindex quit +@cindex exit +@cindex close +@cindex next screen + +When you run @command{adjbacklight} in interactive mode, the following +keys are used to adjust the backlighting: + +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{<control>d} continues to the next backlight +controller, or if you are at the last one, exits 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 <http://www.gnu.org/licenses/>. +@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 + |