Exiting wpa_supplicant

[Nelson Marambio <nelsonmarambio@xxxxxx>]

Dear list,

I try to write a small shellscript that (dis-)connects me with / from 
the WLAN of my university.

I use wpa_supplicant in combination with the -B switch to establish the 
connection. After a pause of 10 seconds I pull an IP address by calling 
dhcpcd.

My question (in context of the wlan-disconnect-script): how can I exit 
wpa_supplicant if it runs in the background ? Up to now it's done by 
"sudo killall wpa_supplicant" but I guess it's not the best way.

Kind regards,
Nelson.