Desktop applications¶

Wayland applications in a machine open windows on your desktop. Links and shared files opened in a machine open with your host's handlers.

Requirements¶

A Wayland session on the host.
Waypipe on the host. nsl looks for waypipe on your PATH; set NSL_WAYPIPE to use another path.
A machine that is not isolated.

nsl doctor shows whether Waypipe was found.

Run an application¶

Install it with the machine's package manager and run it:

nsl run sudo apt-get update
nsl run sudo apt-get install -y galculator  # pick any GUI application
nsl run galculator

Applications started from a shell in the machine work the same way. Perfect for running your favorite editor/IDE.

The desktop session¶

When a command enters or starts a machine from a Wayland session, nsl starts that machine's desktop session if it is not running: a user unit, nsl-UID-vm-ID-desktop-NAME.service, that runs Waypipe between your desktop and the machine. The session restarts after a failure, outlives a stopped machine and ends with the VM.

Commands in the machine receive:

Variable	Value
`WAYLAND_DISPLAY`	The machine's Waypipe socket
`XDG_SESSION_TYPE`	`wayland`, so Chromium, Electron and Qt choose Wayland
`BROWSER`	`nsl-open`

Machines have no X server. Applications that support only X11 do not open windows.

A machine with a connected window is not idle, so it keeps running while the window is open.

Open links and files on the host¶

nsl-open https://github.com/frostyard/nsl
nsl-open /mnt/host/var/home/you/report.pdf   # any path under /mnt/host
nsl-open report.pdf                          # relative, from a directory under /mnt/host

nsl-open asks the host to open an http or https URL, or a path under /mnt/host, with your default handler. It is the machine's BROWSER and its handler for web links, so tools that open a browser open yours.

The host side is a per-machine broker. It accepts only web URLs and /mnt/host paths whose host paths lie in the shared trees, and refuses every other target. These checks keep a machine from naming host files outside the shares. They are not a security boundary: a machine can already write your files.

Troubleshooting¶

nsl logs NAME shows the desktop session's recent logs.
A command started outside a Wayland session, such as over SSH, does not start a desktop session. The next command from your desktop does.