To support tethering, your target system must enable packet filtering in the QNX networking stack (io-pkt-*) and launch the pfctl utility to communicate with this service.
mount -Tio-pkt /lib/dll/lsm-pf-*.so
waitfor /dev/pf; pfctl -e -f /etc/pf.conf
With pfctl, you must use the -e option to enable the packet filter and -f to name the configuration file that contains the rules that support tethering.
You should put the above command sequence in your startup script, after the command that starts io-pkt-*.
For more details on the packet filter client utility and the device that it controls, see the pf, /etc/pf.conf, and pfctl entries in the Utilities Reference.
After installing the Networking Middleware package, you must either rename pf.conf.tetherman to pf.conf (and hence, replace the existing file in your QNX SDP installation), or merge the contents of this file from the package into the existing pf.conf file. The first option is useful for the out-of-box experience, when you don't have an existing target image with a customized pf.conf file. The second option is useful for integrating wireless networking into an existing system, because you will pick up the tetherman filtering rules while keeping any existing rules needed for your system.
# Anchor for tetherman rdr-anchor "tethering" nat-anchor "tethering"