binding a socket to a specific interface

[Edgar Fuß <ef%math.uni-bonn.de@localhost>]

Is there a way to bind a socket to a specific interface?
The check_dhcp monitoring plugin needs to do that; on Linux, it does
	setsockopt(sock, SOL_SOCKET, SO_BINDTODEVICE, ...)
else it does nothing really, making my DHCP checks fail.
dhclient seems to use BPF.