diff '--color=auto' -ruN echoping-6.0.2_p434.orig/acinclude.m4 echoping-6.0.2_p434/acinclude.m4
--- echoping-6.0.2_p434.orig/acinclude.m4	2024-11-09 22:26:58.045557458 +0100
+++ echoping-6.0.2_p434/acinclude.m4	2024-11-09 22:26:35.950243412 +0100
@@ -87,6 +87,7 @@
 AC_MSG_CHECKING(if libnsl is mandatory)
 AC_TRY_LINK([#include <sys/types.h>
              #include <netinet/in.h>
+             #include <netdb.h>
              char *domain;  ], 
  [gethostbyname(domain)], dnl
  [AC_MSG_RESULT(no)], dnl