diff --git a/configure.ac b/configure.ac
index 7342dcb77..03cc3f869 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1908,7 +1908,7 @@ AC_CHECK_DECLS([O_NONBLOCK], , ,
 #endif
 	])
 
-AC_CHECK_DECLS([writev], , , [
+AC_CHECK_DECLS([readv, writev], , , [
 #include <sys/types.h>
 #include <sys/uio.h>
 #include <unistd.h>
diff --git a/openbsd-compat/openbsd-compat.h b/openbsd-compat/openbsd-compat.h
index 8155a0dd7..b48fb9342 100644
--- a/openbsd-compat/openbsd-compat.h
+++ b/openbsd-compat/openbsd-compat.h
@@ -170,10 +170,18 @@ int BSDgetopt(int argc, char * const *argv, const char *opts);
 #include "openbsd-compat/getopt.h"
 #endif
 
-#if defined(HAVE_DECL_WRITEV) && HAVE_DECL_WRITEV == 0
+#if ((defined(HAVE_DECL_READV) && HAVE_DECL_READV == 0) || \
+    (defined(HAVE_DECL_WRITEV) && HAVE_DECL_WRITEV == 0))
 # include <sys/types.h>
 # include <sys/uio.h>
+
+# if defined(HAVE_DECL_READV) && HAVE_DECL_READV == 0
+int readv(int, struct iovec *, int);
+# endif
+
+# if defined(HAVE_DECL_WRITEV) && HAVE_DECL_WRITEV == 0
 int writev(int, struct iovec *, int);
+# endif
 #endif
 
 /* Home grown routines */