WIFI connections for Pi-Star on the raspberry pi

My hotspot is setup to connect to three WiFi networks 1) my home network, 2) tethered to my mobile phone and 3) my hotspot. The Pi-Star wifi settings (and for most Linux distrubtions are stored in a file located in /etc/wpa_supplicant/wpa_supplicant.conf.

Mine looks like this:

#cat /etc/wpa_supplicant/wpa_supplicant.conf
ctrl_interface=DIR=/var/run/wpa_supplicant GROUP=netdev
update_config=1
ap_scan=1
fast_reauth=1
country=UK

network={
    ssid="wifihome"
    psk="mypassword"
    id_str="0"
    priority=100
}

network={
    ssid="mobilephone"
    psk="mypassword"
    id_str="1"
    priority=99
}

network={
        ssid="holidayhotspot"
        psk="mypassword"
        id_str="2"
        priority=98
}

Note that each entry has a unique id_str value. Additionally I have set a preference order for connecting using the priority field. The higher the value the higher the preference.

If you want to edit this file by hand on your pi-star OS, make sure the file is writable by issuing the rpi-rw command and then sudo nano /etc/wpa_supplicant/wpa_supplicant.conf to make the edits.