+# 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.])], [])
+