charnetwork

A small network switcher for Linux (dhcpcd + wpa_supplicant). It lists your Ethernet, USB tethering and Wi-Fi connections and lets you pick which one carries traffic.

• Shows each connection's address, IPv4/IPv6 gateways and live up/down speed
• Use sends traffic through one connection and keeps the others connected
• Only uses one connection and disconnects the others, once it is ready
• Off / On and All off / All on bring connections down or up

Written in C with SDL3, OpenGL 3.3 and FreeType.

Dependencies

To build: a C compiler, make, pkg-config and the development files for SDL3, FreeType and libpng. On Void:

sudo xbps-install base-devel pkg-config SDL3-devel freetype-devel libpng-devel

To run: ip (iproute2), iw, dhcpcd, and pkexec (polkit) with a polkit agent for the password prompt.

Build

./setup.sh

This checks for the libraries and runs make.

Run

./run.sh

Key	Action
↓ ↑ / j k	Select a connection
Space	On / off
u	Use
o	Only
r	Refresh
q / Esc	Quit

Changing connections needs root, so the app runs helper/charnetwork-helper through pkexec and your polkit agent asks for your password.

run.sh builds the app if needed and keeps anything it writes in .data/. Virtual interfaces (bridges, containers) are hidden; CHARNETWORK_ALL=1 ./run.sh shows them.

Install

Add charnetwork to your app launcher:

./desktop.sh --link

Optional: to type the password once every few minutes instead of for every change, install the helper and a polkit policy (uses sudo):

./setup.sh --system    # install
./setup.sh --remove    # remove again

These are the only files charnetwork puts outside its folder:

/usr/local/libexec/charnetwork-helper
/usr/share/polkit-1/actions/org.charnetwork.helper.policy

The installed helper is used only while it matches helper/charnetwork-helper exactly, so rerun --system after changing it.

Tests

make test

Needs Python 3. The helper runs against faked commands and the app runs without a window, so the tests never touch your network.

Bundled fonts are Noto Sans and Noto Serif (SIL Open Font License); the license is in fonts/.