To have your computer search and connect to ANY Open Wifi modifiy the following two files:
*This was tested on Ubuntu 14.04 x64 Server
iface wlan0 inet manual
iface open_wifi inet dhcp
Now bring interface down/up and check status.
sudo ifconfig wlan0 down && sudo ifconfig wlan0 up && sudo wpa_cli -i wlan0 status
use both ifconfig/ping
IF ifconfig show's no private IP and ping should fail
try again and should show privateIP and ping should succeed.
To manually connect via config for debugging use this:
wpa_supplicant -d -i wlan0 -c /etc/wpa_supplicant/wpa_supplicant.conf -D wext
-d = debug/verbose -dd == super verbose
-D = driver
wext = "catch-all driver"
I tested with phone via hotspot which is PERFECT because it tells you when a client connects. I also turned off HotSpot and it reconnected when it turned back on! Only down side is if you are in a populated area, like my testing environment, it connected to "Xfinity-Wifi" which is open and then I had to reboot then it seemed to go with my hotspot due to it being a stronger signal. But once it was on XFinity it would not leave it unless I specified the Open Network SSID inside of the wpa_supplicant.conf OR rebooted.