Quick configuration of WiFi on a Raspberry Pi

gistfile1.sh

cat << EOF | sudo tee /etc/network/interfaces
auto lo

iface lo inet loopback
iface eth0 inet dhcp

allow-hotplug wlan0
auto wlan0
iface wlan0 inet dhcp
wpa-conf /etc/wpa_supplicant/wpa_supplicant.conf
EOF

sudo mkdir -p /etc/wpa_supplicant

cat << EOF | sudo tee /etc/wpa_supplicant/wpa_supplicant.conf
update_config=1
ctrl_interface=/var/run/wpa_supplicant

network={
 ssid="MEUSSID"
 psk="MINHASENHA"
}
EOF