s6-service-definitions/sv/wpa_supplicant-srv/run

#!/bin/execlineb -P
envfile /etc/s6/config/wpa_supplicant.conf
importas -uD "wlan0" WPA_INTERFACE WPA_INTERFACE
fdmove -c 2 1
exec /sbin/wpa_supplicant -i ${WPA_INTERFACE} -c /etc/wpa_supplicant/wpa_supplicant.conf