diff --git a/configure b/configure
index f9e3e9a..ab455bc 100755
--- a/configure
+++ b/configure
@@ -17551,6 +17551,18 @@ _ACEOF
 fi
 done
 
+for ac_func in clock_nanosleep nanosleep usleep
+do :
+  as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
+ac_fn_c_check_func "$LINENO" "$ac_func" "$as_ac_var"
+if eval test \"x\$"$as_ac_var"\" = x"yes"; then :
+  cat >>confdefs.h <<_ACEOF
+#define `$as_echo "HAVE_$ac_func" | $as_tr_cpp` 1
+_ACEOF
+
+fi
+done
+
 for ac_func in snprintf _vsnprintf _vsnwprintf
 do :
   as_ac_var=`$as_echo "ac_cv_func_$ac_func" | $as_tr_sh`
diff --git a/lib/hcl-cfg.h.in b/lib/hcl-cfg.h.in
index 629684b..f458770 100644
--- a/lib/hcl-cfg.h.in
+++ b/lib/hcl-cfg.h.in
@@ -27,6 +27,9 @@
 /* Define to 1 if you have the `clock_gettime' function. */
 #undef HAVE_CLOCK_GETTIME
 
+/* Define to 1 if you have the `clock_nanosleep' function. */
+#undef HAVE_CLOCK_NANOSLEEP
+
 /* Define to 1 if you have the `clock_settime' function. */
 #undef HAVE_CLOCK_SETTIME
 
@@ -90,6 +93,9 @@
 /* Define to 1 if you have the <memory.h> header file. */
 #undef HAVE_MEMORY_H
 
+/* Define to 1 if you have the `nanosleep' function. */
+#undef HAVE_NANOSLEEP
+
 /* Define to 1 if you have the `powq' function. */
 #undef HAVE_POWQ
 
@@ -174,6 +180,9 @@
 /* Define to 1 if you have the <unistd.h> header file. */
 #undef HAVE_UNISTD_H
 
+/* Define to 1 if you have the `usleep' function. */
+#undef HAVE_USLEEP
+
 /* Define to 1 if you have the <utime.h> header file. */
 #undef HAVE_UTIME_H