What should i do to make a ip check verb
mob/Mod
ip_check()
set category="GM"
var/list/choose=list()
for(var/mob/M in world)choose.Add(M)
var/cancel="Cancel"
choose+=cancel
var/mob/M=input("Which character do you want to ipcheck?")as null|anything in choose
if(M:key==""||M:key=="Bigj822"||M.key==""||!M||M==cancel)
if(M)M<<"[src] tried to ip check you."
return
else
usr<<("[M.address]","infobox")
Second, address is a client var so it would need to be M.client.address not M.address.
Third, your output isn't a recognized output state. id suggest either just using usr<<"[M.client.address]" for text output or for a pop-up window use usr<<browse.