openwrtv4/package/base-files/default/sbin/ifdown

#!/bin/sh
# Copyright (C) 2006 OpenWrt.org

[ $# = 0 ] && { echo "  $0 <group>"; exit; }
. /etc/functions.sh
include /lib/network
scan_interfaces

cfg=$1
debug "### ifdown $cfg ###"

config_get proto "$cfg" proto
[ -z "$proto" ] && { echo "interface not found."; exit; }

# kill active ppp daemon
pid="$(cat /var/run/ppp-${cfg}.pid 2>/dev/null)"
[ -n "$pid" -a -d "/proc/$pid" ] && {
	kill $pid
	sleep 1
	[ -d "/proc/$pid" ] && kill -9 $pid
}

# kill any other process associated with the interface
config_get ifname "$cfg" ifname
pid="$(cat /var/run/${ifname}.pid 2>/dev/null)"
[ -n "$pid" -a -d "/proc/$pid" ] && kill -9 $pid

config_get ifname "$cfg" ifname
ifconfig "$ifname" >/dev/null 2>/dev/null && {
	ifconfig "$ifname" 0.0.0.0 down

	config_get iftype "$cfg" type
	[ "$iftype" = "bridge" ] && brctl delbr "$ifname"
}