NAME
    rainbarf - CPU/RAM/battery stats chart bar for tmux (and GNU screen)

VERSION
    version 1.5

SYNOPSIS
     rainbarf --tmux --width 40 --no-battery

DESCRIPTION
    Fancy resource usage charts to put into the tmux
    <http://tmux.sourceforge.net/> status line. The CPU utilization history
    chart is tinted with the following colors to reflect the system memory
    allocation:

    *   green: free memory;

    *   yellow: active memory;

    *   blue: inactive memory;

    *   red: wired memory on *Mac OS X* / *FreeBSD*; "unaccounted" memory on
        *Linux*;

    *   cyan: cached memory on *Linux*, buf on *FreeBSD*.

    *   magenta: used swap memory.

    If available, battery charge is displayed on the right.

    Just go to <https://github.com/creaktive/rainbarf> to see some
    screenshots.

USAGE
  Installation
    *   Traditional way:

         perl Build.PL
         ./Build test
         ./Build install

    *   Homebrew <http://brew.sh/> way:

         brew install rainbarf

    *   MacPorts <http://www.macports.org/> way:

         port install rainbarf

    *   CPAN way:

         cpan -i App::rainbarf

    *   Modern Perl way:

         cpanm git://github.com/creaktive/rainbarf.git

  Configuration
    Add the following line to your ~/.tmux.conf file:

     set-option -g status-utf8 on
     set -g status-right '#(rainbarf)'

    Or, under *GNOME Terminal*:

     set-option -g status-utf8 on
     set -g status-right '#(rainbarf --rgb)'

    Reload the tmux config by running "tmux source-file ~/.tmux.conf".

CONFIGURATION FILE
    "~/.rainbarf.conf" can be used to persistently store "OPTIONS":

     # example configuration file
     width=20   # widget width
     bolt       # fancy charging character
     remaining  # display remaining battery
     rgb        # 256-colored palette

    "OPTIONS" specified via command line override that values. Configuration
    file can be specified via "RAINBARF" environment variable:

     RAINBARF=~/.rainbarf.conf rainbarf

OPTIONS
    "--help"
        This.

    "--[no]battery"
        Display the battery charge indicator. Enabled by default.

    "--[no]remaining"
        Display the time remaining until the battery is fully charged/empty.
        See "CAVEAT". Disabled by default.

    "--[no]bolt"
        Display even fancier battery indicator. Disabled by default.

    "--[no]bright"
        Tricky one. Disabled by default. See "CAVEAT".

    "--[no]rgb"
        Use the RGB palette instead of the system colors. Also disabled by
        default, for the same reasons as above.

    "--fg COLOR_NAME"
        Force chart foreground color.

    "--bg COLOR_NAME"
        Force chart background color.

    "--[no]loadavg"
        Use load average <https://en.wikipedia.org/wiki/Load_(computing)>
        metric instead of CPU utilization. You might want to set the "--max"
        threshold since this is an absolute value and has varying ranges on
        different systems. Disabled by default.

    "--[no]swap"
        Display the swap usage. Used swap amount is added to the total
        amount, but the free swap amount is not! Disabled by default.

    "--max NUMBER"
        Maximum "loadavg" you expect before rescaling the chart. Default is
        1.

    "--order INDEXES"
        Specify the memory usage bar order. The default is "fwaic" ( free,
        wired, active, inactive & cached ).

    "--[no]tmux"
        Force "tmux" colors mode. By default, rainbarf detects automatically
        if it is being called from "tmux" or from the interactive shell.

    "--screen"
        screen(1)
        <http://manpages.ubuntu.com/manpages/hardy/man1/screen.1.html>
        colors mode. Experimental. See "CAVEAT".

    "--width NUMBER"
        Chart width. Default is 38, so both the chart and the battery
        indicator fit the "tmux" status line. Higher values may require
        disabling the battery indicator or raising the "status-right-length"
        value in ~/.tmux.conf.

    "--datfile FILENAME"
        Specify the file to log CPU stats to. Default: $HOME/.rainbarf.dat

    "--skip NUMBER"
        Do not write CPU stats if file already exists and is newer than this
        many seconds. Useful if you refresh "tmux" status quite frequently.

CAVEAT
  Time remaining
    If the "--remaining" option is present but you do not see the time in
    your status bar, you may need to increase the value of
    "status-right-length" to 48.

  Color scheme
    If you only see the memory usage bars but no CPU utilization chart,
    that's because your terminal's color scheme need an explicit distinction
    between foreground and background colors. For instance, "red on red
    background" will be displayed as a red block on such terminals. Thus,
    you may need the ANSI bright attribute for greater contrast, or maybe
    consider switching to the 256-color palette. There are some issues with
    that, though:

    1.  Other color schemes (notably, solarized
        <http://ethanschoonover.com/solarized>) have different meaning for
        the ANSI bright attribute. So using it will result in a quite
        psychedelic appearance. 256-color pallette, activated by the "--rgb"
        flag, is unaffected by that.

    2.  The older versions of Term::ANSIColor dependency do not recognize
        bright/RGB settings, falling back to the default behavior (plain 16
        colors). However, the whole Term::ANSIColor is optional, it is only
        required to preview the effects of the "OPTIONS" via command line
        before actually editing the ~/.tmux.conf. That is, "rainbarf
        --bright --tmux" is guaranteed to work despite the outdated
        Term::ANSIColor!

    Another option is skipping the system colors altogether and use the RGB
    palette ("rainbarf --rgb"). This fixes the *issue 1*, but doesn't affect
    the *issue 2*. It still looks better, though.

  Persistent storage
    CPU utilization stats are persistently stored in the ~/.rainbarf.dat
    file. Every rainbarf execution will update and rotate that file. Since
    "tmux" calls rainbarf periodically (every 15 seconds, by default), the
    chart will display CPU utilization for the last ~9.5 minutes (15 * 38).
    Thus, several "tmux" instances running simultaneously for the same user
    will result in a faster chart scrolling.

  screen
    Stable "screen" version unfortunately has a broken UTF-8 handling
    specifically for the status bar. Thus, I have only tested the rainbarf
    with the variant from <git://git.savannah.gnu.org/screen.git>. My
    ~/.screenrc contents:

     backtick 1 15 15 rainbarf --bright --screen
     hardstatus string "%1`"
     hardstatus lastline

REFERENCES
    *   top(1)
        <http://developer.apple.com/library/mac/documentation/Darwin/Referen
        ce/ManPages/man1/top.1.html> is used to get the CPU/RAM stats if no
        /proc filesystem is available.

    *   ioreg(8)
        <http://developer.apple.com/library/mac/documentation/Darwin/Referen
        ce/ManPages/man8/ioreg.8.html> is used to get the battery status on
        *Mac OS X*.

    *   ACPI <http://www.tldp.org/howto/acpi-howto/usingacpi.html> is used
        to get the battery status on *Linux*.

    *   Battery <https://github.com/Goles/Battery> was a source of
        inspiration.

    *   Spark <http://zachholman.com/spark/> was another source of
        inspiration.

AUTHOR
    Stanislaw Pusep <stas@sysd.org>

CONTRIBUTORS
    *   Chris Knadler <https://github.com/cknadler>

    *   cinaeco <https://github.com/cinaeco>

    *   Clemens Hammacher <https://github.com/hammacher>

    *   H.Merijn Brand <https://github.com/Tux>

    *   Henrik Hodne <https://github.com/henrikhodne>

    *   Joe Hassick <https://github.com/jh3>

    *   Josh Matthews <https://github.com/jmatth>

    *   Lars Engels <https://github.com/larsengels>

    *   Sergey Romanov <https://github.com/sergeyromanov>

    *   Tom Cammann <https://github.com/takac>

    *   Tuomas Jormola <https://github.com/tjormola>

COPYRIGHT AND LICENSE
    This software is copyright (c) 2026 by Stanislaw Pusep <stas@sysd.org>.

    This is free software; you can redistribute it and/or modify it under
    the same terms as the Perl 5 programming language system itself.

