raspberry pi headless code example

Example 1: raspberry pi set wifi headless

crate a file in the root folder of the sd card ("boot") called 
wpa_supplicant.conf
===========contents of file:=================
ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1
country=

network={
 ssid=""
 psk=""
}

Example 2: raspberry pi headless

create a file in the root folder of the sd card ("boot") called 
wpa_supplicant.conf
add scan_ssid=1 if connecting to hidden network
===========contents of file:=================
ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1
country=

network={
 ssid=""
 psk=""
}