This is correctly handled by ipaddr/ng_ipaddr.h today, and the check
in tool.h isn't required any more -- and caused errors on OpenBSD 5.0:
In file included from ./../tool/tool.h:23:
/usr/include/arpa/inet.h:74:
warning: "struct in_addr" declared inside parameter list
#include "portab.h"
-#ifdef HAVE_ARPA_INET_H
-# include <arpa/inet.h>
-#else
-# define PF_INET AF_INET
-#endif
-
GLOBAL void ngt_TrimLastChr PARAMS((char *String, const char Chr ));
GLOBAL void ngt_TrimStr PARAMS((char *String ));