Files
punktfunk/docs-site/content/docs/host-cli.md
T
enricobuehler 12843fe253 feat(protocol,clients): codec preference negotiation + Linux client decodes per Welcome (Phase 2a)
Adds a client-selectable **preferred codec** and wires the core + ABI + probe + Linux client to
negotiate and decode it. (Windows/Apple/Android follow in 2b.)

**Core:**
- `Hello.preferred_codec` (a single CODEC_* bit, 0 = auto) — a soft hint appended after
  `video_codecs`. `resolve_codec(client, host, preferred)` now honors the preference when the host
  can also emit it, else falls back to precedence (HEVC > AV1 > H.264). Roundtrip + preference tests.
- `NativeClient::connect` takes `video_codecs` + `preferred_codec`; `NativeClient.codec` exposes the
  resolved `Welcome.codec`.
- ABI: `punktfunk_connect_ex7` (adds the two codec params; `ex6` delegates to it advertising
  HEVC-only) + `punktfunk_connection_codec` getter + `PUNKTFUNK_CODEC_{H264,HEVC,AV1}` constants
  (drift-guarded against the wire values). Header regenerated.

**Host:** passes `hello.preferred_codec` into `resolve_codec`.

**probe:** `--codec h264|hevc|av1|auto` sets the preference (still advertises it can decode all
three); the dump extension already follows the resolved codec.

**Linux client:** advertises the codecs FFmpeg can actually decode (`decodable_codecs()`), threads
the user's `codec` setting as the preference, and builds the decoder — both the software and VAAPI
paths, plus the mid-session VAAPI→software demotion — from the negotiated `Welcome.codec` instead of
hardcoding HEVC. New "Video codec" dropdown in Preferences (Automatic/HEVC/H.264/AV1).

Live-validated on the dev box: probe `--codec hevc` against a software (H.264-only) host resolves to
H.264 (graceful soft-preference fallback), no failure. clippy + core (57) + host (133) tests green.

Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
2026-07-02 00:13:26 +00:00

4.0 KiB

title, description
title description
Host CLI The punktfunk-host commands and the flags you'll actually use.

The host is one binary, punktfunk-host. Most of the time you'll run a single command; the rest reads its settings from host.env.

serve

The normal way to run a host. By default serve starts the secure native host: the native punktfunk/1 server (QUIC, SPAKE2 PIN pairing, per-direction AEAD) plus the management API/web console — all in one process. The native plane is always on; there is no flag to turn it off.

punktfunk-host serve

Add --gamestream (alias --moonlight) to also run the GameStream/Moonlight-compatible planes (nvhttp pairing, RTSP, ENet control, _nvstream mDNS) — required for stock Moonlight clients. This is opt-in because GameStream carries inherent on-path weaknesses (pairing over plain HTTP; its legacy control encryption can reuse GCM nonces — security-review #5/#9), so enable it only on a trusted LAN. The native plane is immune to those issues.

punktfunk-host serve --gamestream
Flag Meaning
--gamestream / --moonlight Also run the GameStream/Moonlight-compat planes (for stock Moonlight clients). Opt-in, trusted-LAN only — see above.
--native No-op. The native punktfunk/1 server always runs in serve; kept only for backward compatibility.
--native-port <PORT> Native QUIC port (default 9777).
--open Don't require pairing — serve any device on the network. Off by default; only for trusted single-user setups.
--mgmt-bind <IP:PORT> Management API address (default loopback 127.0.0.1:47990).
--mgmt-token <TOKEN> Override the bearer token for the management API.

These are the only flags serve accepts.

The management API is always HTTPS with bearer-token auth. If you don't pass --mgmt-token, a token is auto-generated and persisted to ~/.config/punktfunk/mgmt-token; --mgmt-token only overrides it. A token is required when you bind the API off loopback with --mgmt-bind. Every endpoint is documented in the interactive API Reference.

By default the host requires pairing — see Pairing & Trust. On serve you arm pairing from the web console (or mgmt API); the host then displays a 4-digit PIN. Pass --open to turn off the mandatory-pairing default and serve any device on the network (trusted single-user setups only). The pairing flags below are punktfunk1-host-only and do not apply to serve.

punktfunk1-host

A standalone native-only host, mainly for testing the punktfunk/1 path without the GameStream server or web console.

punktfunk-host punktfunk1-host --source virtual
Flag Meaning
--port <N> QUIC listen port (default 9777).
--source synthetic · virtual virtual uses a real virtual display + NVENC; synthetic emits test frames.
--seconds <N> / --frames <N> Bound each session by wall-clock seconds or frame count.
--max-concurrent <N> Stream at most N sessions at once (default 4); overflow waits in the queue.
--max-sessions <N> Exit after N sessions (0 = serve forever).
--allow-pairing Accept PIN pairing; the host prints a PIN when a client pairs.
--require-pairing Only serve paired devices (implies --allow-pairing).

--max-concurrent, --allow-pairing, and --require-pairing are punktfunk1-host-onlyserve does not accept them. On serve you arm pairing from the web console instead, and concurrency is fixed at the built-in default (4 sessions) rather than settable from the command line.

Both serve and punktfunk1-host advertise the host on the network so clients can discover it. List hosts from another machine with punktfunk-probe --discover.

Environment

Most behaviour (compositor, video source, input backend, zero-copy) is set in host.env, not on the command line. When running as a service, the unit loads host.env for you.