added <netinet/in.h> include and C++ header guards

git-svn-id: file:///srv/svn/repos/haiku/trunk/current@1654 a95241bf-73f2-0310-859d-f6bbb57e9c96

headers/posix/netdb.h

@@ -3,8 +3,14 @@
 #ifndef NETDB_H
 #define NETDB_H
 
+#include <netinet/in.h>
 #include <errno.h>
 
+#ifdef __cplusplus
+extern "C" {
+#endif  
+
+
 #ifndef MAXHOSTNAMELEN
 #define MAXHOSTNAMELEN 64
 #endif
@@ -174,4 +180,8 @@ void endservent (void);
  */
 #define ERRSET_SUCCESS          0
 
+#ifdef __cplusplus
+}
+#endif 
+
 #endif /* NETDB_H */