use _PLATFORM_NEEDINETIN6H

lib/isc/include/isc/platform.h.in

@@ -26,6 +26,12 @@
  *** Network.
  ***/
 
+/*
+ * Define if this system needs the <netinet/in6.h> header file included
+ * for full IPv6 support (pretty much only UnixWare).
+ */
+@ISC_PLATFORM_NEEDNETINETIN6H@
+
 /*
  * Define if this system needs the <netinet6/in6.h> header file included
  * to support in6_pkinfo (pretty much only BSD/OS).

lib/isc/unix/include/isc/net.h

@@ -73,8 +73,11 @@
 
 #include <netinet/in.h>		/* Contractual promise. */
 #include <arpa/inet.h>		/* Contractual promise. */
+#ifdef ISC_PLATFORM_NEEDNETINETIN6H
+#include <netinet/in6.h>	/* Required on UnixWare. */
+#endif
 #ifdef ISC_PLATFORM_NEEDNETINET6IN6H
-#include <netinet6/in6.h>	/* Required for in6_pktinfo. */
+#include <netinet6/in6.h>	/* Required on BSD/OS for in6_pktinfo. */
 #endif
 
 #include <isc/types.h>

lib/lwres/include/lwres/net.h

@@ -54,8 +54,11 @@
 
 #include <netinet/in.h>
 #include <arpa/inet.h>
+#ifdef LWRES_PLATFORM_NEEDNETINETIN6H
+#include <netinet/in6.h>	/* Required on UnixWare. */
+#endif
 #ifdef LWRES_PLATFORM_NEEDNETINET6IN6H
-#include <netinet6/in6.h>
+#include <netinet6/in6.h>	/* Required on BSD/OS for in6_pktinfo. */
 #endif
 
 #include <lwres/result.h>

lib/lwres/include/lwres/platform.h.in

@@ -27,7 +27,12 @@
  ***/
 
 /*
- * Define if this system has the <netinet6/in6.h> header file.
+ * Define if this system needs the <netinet/in6.h> header file for IPv6.
+ */
+@LWRES_PLATFORM_NEEDNETINETIN6H@
+
+/*
+ * Define if this system needs the <netinet6/in6.h> header file for IPv6.
  */
 @LWRES_PLATFORM_NEEDNETINET6IN6H@