auto lo
iface lo inet loopback

auto eth0
    iface eth0 inet dhcp
    pre-up sleep 20

auto ap0
    iface ap0 inet static
    address 192.168.77.1
    netmask 255.255.255.0

auto client0
    iface client0 inet manual
    pre-up ifconfig $IFACE up
    post-down ifconfig $IFACE down