---
name: "lnpd"
section: "8"
platform: "linux"
package: "lnpd"
version: "0.9.0-11+b2"
release: "Debian 12 (Bookworm)"
platforms: ["linux"]
url: "https://new.carta.tech/lnpd"
---

# lnpd(8)

a LinuX Interface to the BrickOS Networking Protocol

## NAME

lnpd - a LinuX Interface to the BrickOS Networking Protocol

## SYNOPSIS

**lnpd** \[*-e*mseconds*\]* \[*-f*\] \[*-l*\] \[*-m*number*\]* \[*-n*\] \[*-p*port*\]* \[*-r*\] \[*-t*tty\_device*\]* \[*-v*level*\]*

## DESCRIPTION

**lnpd** is a LinuX daemon that allows multiple clients to connect to a LEGO RCX  running Markus L. Noga's famous BrickOS (formerly legOS) operating system  and exchange messages using the LNP protocol.

## OPTIONS

A summary of options understood by  **lnpd**

- **-d**

  Don't go into background

- **-e\|--extrawait={mseconds}**

  Extra wait time for lnp

- **-f\|--fast**

  Run LNP at 4800 baud

- **-l\|--log\[=filename\]**

  Enable logging to syslog or file\
   NOTE: filename of '-' means to log to stdout.

- **-m\|--maxclients={number}**

  Set max number of lnpd clients (default 16).

- **-n\|--nolock**

  Do not manage tty lockfiles.

- **-p\|--port={TCP\_Port}**

  Daemon should listen on port {TCP\_Port}. Default is port 7776.

- **-r\|--realtime**

  Run daemon in realtime mode.

- **-t\|--tty={tty\_device}**

  Use {tty\_device}. Defaults to /dev/ttyS0.

- **-v\|--verbosity={level}**

  Enable enhanced logging. Valid levels are: d, l, i, a, and c.

- **-h**

  Show similar help text at command-line.

- **-u**

  Show short usage message.

- **-V\|--version**

  Display lnpd version

  Mandatory or option arguments to long options are also mandatory or optional for any corresponding short options.

## FILES

- **/dev/ttyS0**

  The default device for lnpd. (Also See -t: in OPTIONS, above).

- **/usr/share/doc/lnpd/examples/lnptest.c**

  sample BrickOS code to be built and downloaded to your RCX. This code allows you to quickly ascertain that the lnpd daemon is working with your RCX and lnpd installation.

- **/bin/lnptest**

  a simple test program which uses lnpd to communicate with the lnptest program downloaded into your RCX for testing with this program.

## SEE ALSO

You'll find additional documentation in /usr/share/doc/lnpd (on Debian GNU/Linux systems)

## AUTHOR

lnpd was written by Martin Cornelius \<Martin.Cornelius@t-online.de\>  This man page was written by Stephen Moraco \<stephen@users.sourceforge.net\>