batsignal is a lightweight battery daemon written in C that notifies the user about various battery states. It is intended for minimal window managers, but can be used in any environment that supports desktop notifications via libnotify.

Customizable messages via libnotify on three configurable battery levels. A fourth configurable battery level will execute an arbitrary system command. In order to use as few system resources as possible, fewer battery checks are performed while the battery is discharging and the level of charge is not near a warning level.

By default, batsignal will attempt to detect the correct battery to monitor.

Batsignal requires the following software to build:

• C compiler
• libnotify
• make
• pkg-config

Run the following command to build and install batsignal:

$ make
$ sudo make install

See man batsignal for details.

batsignal is configured using command options - see man batsignal for a complete list. these options can be passed manually from the terminal, added to the command invocation in shell profile scripts, or during window manager initialization.

A systemd user service can be installed by running:

$ make install-service

And can be enabled and started with:

$ sudo systemctl daemon-reload
$ systemctl --user enable batsignal.service
$ systemctl --user start batsignal.service

The service unit starts batsignal with default options. To customize the options used by the service, create a drop-in file that overrides ExecStart. For example:

$ mkdir -p ~/.config/systemd/user/batsignal.service.d
$ printf '[Service]\nExecStart=\nExecStart=batsignal -c 10 -w 30 -f 97' > ~/.config/systemd/user/batsignal.service.d/options.conf

batsignal is written by Corey Hinshaw. It was originally forked from juiced by Aaron Marcher.

For supporting language-server freatures, the compile_commands.json file is necessary (at least for the clangd-lsp). This can be generated with Bear:

$ bear -- make

Copyright (c) 2018-2024 Corey Hinshaw
Copyright (c) 2016-2017 Aaron Marcher

Permission to use, copy, modify, and/or distribute this software for any purpose with or without fee is hereby granted, provided that the above copyright notice and this permission notice appear in all copies.

THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.