# WHATPORT(1234)

## NAME

port 1234 — QEMU gdbstub / VLC streaming (unofficial); Infoseek search-agent (registered) — The classic "pick a memorable port" number — QEMU's debug stub and VLC's stream examples both land here.

Protocol: TCP/UDP  
IANA registry

## DESCRIPTION

The IANA registration is search-agent, "Infoseek Search Agent", which has no practical presence today. What actually uses 1234 is convention: QEMU's `-s` flag makes the guest's gdbstub listen on TCP 1234 so GDB can attach, and VLC's UDP/RTP streaming examples use 1234 as the destination port. Because it is short and easy to remember, ad-hoc test servers and tutorials pick it constantly, so an open 1234 usually means someone's debugger, stream, or throwaway listener rather than a defined service.

## EXPOSURE

**Do not expose.** A QEMU gdbstub is unauthenticated full control of the guest, including memory writes — bind it to localhost. Ad-hoc listeners on 1234 are, by nature, not hardened.

## CHECK

```sh
sudo lsof -nP -iTCP:1234 -sTCP:LISTEN
```

## SEE ALSO

- docs — [QEMU — GDB usage (`-s` listens for gdb on TCP port 1234)](https://www.qemu.org/docs/master/system/gdb.html) (qemu.org)
- docs — [VLC User Documentation — Stream over UDP](https://docs.videolan.me/vlc-user/desktop/3.0/en/advanced/streaming/stream_over_udp.html) (docs.videolan.me)
- iana — [IANA Service Name and Transport Protocol Port Number Registry](https://www.iana.org/assignments/service-names-port-numbers/service-names-port-numbers.xhtml) (iana.org)

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HTML: <https://whatport.net/1234/> · JSON: <https://whatport.net/1234.json> · full dataset: <https://whatport.net/ports.json>