make install
  CC      ipsvd/tcpudp.o
In file included from /usr/include/linux/netfilter_ipv4.h:8,
                 from ipsvd/tcpudp.c:33:
/usr/include/linux/netfilter.h:55: error: field ‘in’ has incomplete type
/usr/include/linux/netfilter.h:56: error: field ‘in6’ has incomplete type
ipsvd/tcpudp.c: In function ‘tcpudpsvd_main’:
ipsvd/tcpudp.c:314: warning: ignoring return value of ‘write’, declared with attribute warn_unused_result
make[1]: *** [ipsvd/tcpudp.o] Error 1
make: *** [ipsvd] Error 2
x@x-laptop:~/apps/mindi-busybox-1.7.3$