--- IO-AIO/autoconf/configure	2005/08/22 23:20:37	1.4
+++ IO-AIO/autoconf/configure	2005/08/23 00:03:14	1.5
@@ -2358,6 +2358,8 @@
 # include <sys/uio.h>
 #elif __hpux
 # include <sys/socket.h>
+#else
+# error unsupported architecture
 #endif
 int main(void)
 {