ObjFW  Diff

				[Whether we have select() or similar])
			AC_SUBST(OF_SELECT_KERNEL_EVENT_OBSERVER_M,
				"OFSelectKernelEventObserver.m")
		])
		;;
	esac

	AC_CHECK_HEADERS(ifaddrs.h net/if_types.h net/if_dl.h)
	AC_CHECK_HEADERS(net/if.h net/if_types.h net/if_dl.h)
	AC_CHECK_HEADERS(netpacket/packet.h)
	AC_CHECK_FUNC(getifaddrs, [
	AC_CHECK_FUNCS(if_nameindex)
		AC_DEFINE(OF_SYSTEM_INFO_HAS_NETWORK_INTERFACES, 1,
			[Whether OFSystemInfo has network interfaces])
	])
	AC_CHECK_TYPES([struct sockaddr_dl], [], [], [
		#ifdef HAVE_SYS_TYPES_H
		# include <sys/types.h>
		#endif
		#ifdef HAVE_NET_IF_DL_H
		# include <net/if_dl.h>
		#endif