Kmscon

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Kmscon is a simple terminal emulator based on Linux kernel mode setting (KMS). It is an attempt to replace the in-kernel VT implementation with a userspace console. Kmscon addresses the limitations of the built-in virtual console by better support for non-Latin characters, better font rendering with anti-aliasing, more fluent DRM backed presentation and better compatibility with HiDPI.

Installation

USE flags

USE flags for sys-apps/kmscon KMS/DRM based virtual Console Emulator

+drm	Enable Linux DRM for backend
+fbdev	Enable Linux FBDev for backend
+gles2	Enable GLES 2.0 (OpenGL for Embedded Systems) support (independently of full OpenGL, see also: gles2-only)
+pango	Enable pango font rendering
debug	Enable extra debug codepaths, like asserts and extra output. If you want to get meaningful backtraces see https://wiki.gentoo.org/wiki/Project:Quality_Assurance/Backtraces
doc	Add extra documentation (API, Javadoc, etc). It is recommended to enable per package instead of globally
elogind	Enable session tracking via sys-auth/elogind
pixman	Enable pixman font rendering
systemd	Enable multiseat support via systemd
test	Enable dependencies and/or preparations necessary to run tests (usually controlled by FEATURES=test but can be toggled independently)

Data provided by the Gentoo Package Database · Last update: 2026-02-19 18:13 More information about USE flags

Emerge

root #emerge --ask sys-apps/kmscon

Configuration

OpenRC

The usage of kmscon on OpenRC is similar to agetty; the following script is based on /etc/init.d/agetty.

FILE /etc/init.d/kmsconvt

#!/sbin/openrc-run

description="KMS System Console"
supervisor="supervise-daemon"
port="${RC_SVCNAME#*.}"
command=/usr/bin/kmscon
command_args_foreground="--vt=${port} --seats=seat0 --no-switchvt --login -- /sbin/agetty -o '-p -- \\u' --noclear -- - $TERM"
pidfile="/run/${RC_SVCNAME}.pid"

depend() {

        after local

        need elogind

}

start_pre() {
        if [ "$port" = "$RC_SVCNAME" ]; then
                eerror "${RC_SVCNAME} cannot be started directly. You must create"
                eerror "symbolic links to it for the ports you want to start"
                eerror "kmscon on and add those to the appropriate runlevels."
                return 1
        else
                export EINFO_QUIET="${quiet:-yes}"
        fi
}

stop_pre() {

        export EINFO_QUIET="${quiet:-yes}"
}

root #cd /etc/init.d

root #for n in $(seq 1 6); do ln -s kmsconvt kmsconvt.tty$n; rc-update add kmsconvt.tty$n default; done

systemd

root #ln -s '/usr/lib/systemd/system/[email protected]' '/etc/systemd/system/[email protected]'

Usage

Note
Currently, the kmscon(1) and kmscon-launch-gui(1) man pages will not be installed unless the package's doc USE flag is enabled; refer to bug #917051 for details.

Refer to the kmscon(1) man page for general information about usage.

GUI environments must be started via the kmscon-launch-gui script, e.g.:

user $kmscon-launch-gui startx

Removal

Prior to removing kmscon, the system must be reconfigured to return to using agetty; a LiveCD may need to be used for this. Kmscon can then safely be removed.

Warning
A VT implementation must always be set, otherwise softlock can occur after reboot. Ensure either agetty (the default) or kmscon is enabled before reboot.

OpenRC

openrc-init

If you are using openrc-init, you need：

root #cd /etc/init.d

root #for n in $(seq 1 6); do rc-update del kmsconvt.tty${n} default; cp agetty agetty.tty${n} ; rc-update add agetty.tty${n} default ; done

sysvinit

TODO

systemd

root #systemctl disable autovt@

root #ln -s '/usr/lib/systemd/system/[email protected]' '/etc/systemd/system/[email protected]'

Troubleshooting

Can't start X / Wayland session on kmscon

An X / Wayland session can't be started directly on kmscon; a Display manager or kmscon-launch-gui must be used instead, e.g.:

user $kmscon-launch-gui sway

Unable to switch between different TTYs

Check /etc/kmscon/kmscon.conf and verify that it includes:

FILE /etc/kmscon/kmscon.conf

switchvt

See also

• Terminal emulator — emulates a video terminal within another display architecture (e.g. in X).