Make SSID, channel and regulatory country display more robust

[martignoni]

Make the display of the SSID, Wi-Fi channel and regulatory country robust, by asking directly the system (instead of reading the config files).

[martignoni]

For this issue, we'll make use of iwcommand, e.g.:

iw wlan0 info | awk '/ssid/{print $2}'
iw wlan0 info | awk '/channel/{print $2}'
iw reg get | awk '/country/{print $2}' | cut -d':' -f1

[martignoni]

If needed, interface name can be obtained with

iw dev | awk '/^\s*Interface/{print $2}'

[martignoni]

Better idea for interface name: look inside directory /sys/class/net.

[martignoni]

This will take care of SSID with a space inside:

iw wlan0 info | awk '/ssid/{$1=""; print substr($0,2)}'

Edit, better yet:

iw wlan0 info | grep ssid | cut -d\  -f2-

[martignoni]

This will print SSID with accented chars:

printf $(iw wlan0 info | awk '/ssid/{$1=""; print substr($0,2)}')

[martignoni]

To get Wi-Fi interface name (source: https://unix.stackexchange.com/a/417845):

find /sys/class/net -follow -maxdepth 2 -name wireless 2> /dev/null | cut -d / -f 5