Is there a way to tell whether an IP address on a system has been assigned via DHCP without using NetworkManager or ResolveCTL?

Back when only ifconfig and route -n and cat /etc/resolv.conf were the only ways to check IP address / Mask / Gateway on a system -- was there a way to determine if these attributes were assigned via DHCP or statically? I know nmcli connection show will indicate if the ipv4.method is auto. And I know ip addr will list dynamic for DHCP assigned addresses. But outside of these two, and even _before_ these two packages existed, was it possible to tell? If so, how?