Loadable stack module that supports Serial Line IP (SLIP) network interface


io-pkt-v4-hc ... –p /lib/dll/ ....


mount –T io-pkt /lib/dll/

Runs on:

QNX Neutrino




The module supports the SL interface, which allows asynchronous serial lines to be used as IPv4 network interfaces using the SLIP protocol.

To use the SL interface:

  1. Load into io-pkt-v4-hc.
  2. Create the interface, using the ifconfig create subcommand.
  3. Use slattach to assign a TTY line to the interface.

Once the interface is attached, you can configure network source and destination addresses and other parameters via ifconfig.

The interface can use Van Jacobson TCP header compression and ICMP filtering. The following flags to ifconfig control these properties of a SLIP link:

Turn on Van Jacobson header compression.
Turn off header compression (the default).
Don't pass through ICMP packets.
Pass through ICMP packets (the default).
If a packet with a compressed header is received, automatically enable compression of outgoing packets (the default).
Don't auto-enable compression.

For more information, see:

Note: SLIP can transmit only IPv4 packets between preconfigured hosts on an asynchronous serial link. It has no provision for address negotiation, carriage of additional protocols (e.g., XNS, AppleTalk, DECNET) and isn't designed for synchronous serial links. This is why SLIP has been superseded by the Point-to-Point Protocol (PPP), which does all of those things, and much more.


sl%d: af%d not supported
The interface was handed a message with addresses formatted in an unsuitable address family; the packet was dropped.

Contributing author: