On my system, to find out the quality of the connected wifi signal I'd have to run
sudo iwconfig wlp6s0 where
wlp6s0 is the name of the device interface I'm using to connect to the wifi. The output doesn't show the link quality or signal level if I don't run the command with
sudo. However, I can get the signal strength of the wifi using
nmcli without using
nmcli dev wifi.
sudo strace iwconfig wlp6s0, I had found that it uses
ioctl system call as indicated in a line the
ioctl(3, SIOCGIWSTATS, 0x7ffd1bd7e960) = 0
But it turns out
strace nmcli dev wifi doesn't use the same system call to obtain the wifi signal strength or relevant informations.
I want to know how
nmcli obtain the information it need to be able to show the wifi signal strength without using
EDIT: Output of both