diff --git a/configure.ac b/configure.ac
index 3e19f41..3baeaab 100644
--- a/configure.ac
+++ b/configure.ac
@@ -129,6 +129,10 @@ AC_CHECK_TYPES([struct serial_struct],,, [[#include <linux/serial.h>]])
 # Check for realpath().
 AC_CHECK_FUNC([realpath], [AC_DEFINE(HAVE_REALPATH, 1, [realpath is available.])], [])
 
+# Check for clock_gettime().
+AC_CHECK_FUNC([clock_gettime],
+	[AC_DEFINE(HAVE_CLOCK_GETTIME, 1, [clock_gettime is available.])], [])
+
 AC_CACHE_CHECK([for visibility control], [sp_cv_visibility_control], [
 	sp_saved_CFLAGS=$CFLAGS
 	CFLAGS="$CFLAGS -Werror"