diff -ur yafc-1.0_orig/configure.ac yafc-1.0_duck/configure.ac
--- yafc-1.0_orig/configure.ac	2003-12-10 11:03:32.000000000 +0100
+++ yafc-1.0_duck/configure.ac	2003-12-10 13:00:27.000000000 +0100
@@ -64,7 +64,8 @@
                  arpa/inet.h \
                  sys/ioctl.h \
                  memory.h \
-                 setjmp.h
+                 setjmp.h \
+		 errno.h
 )
 
 AC_CHECK_HEADERS(dirent.h, [], [