diff --git a/include/dap_common.h b/include/dap_common.h
index a441852a28a8b7bce7509bf5e862a04eef4e10e6..27468c603689d05bf5ee89e2c346281a804d7087 100755
--- a/include/dap_common.h
+++ b/include/dap_common.h
@@ -22,6 +22,7 @@
     You should have received a copy of the GNU General Public License
     along with any DAP based project.  If not, see <http://www.gnu.org/licenses/>.
 */
+#define _XOPEN_SOURCE 700
 
 #pragma once
 
diff --git a/src/dap_common.c b/src/dap_common.c
index 80303416f1421564ea6b51be31bdc32b15c4d50c..d145c6fd48faa1f757bc9d443468f06bc326b015 100755
--- a/src/dap_common.c
+++ b/src/dap_common.c
@@ -21,7 +21,6 @@
     You should have received a copy of the GNU General Public License
     along with any DAP based project.  If not, see <http://www.gnu.org/licenses/>.
 */
-#define _XOPEN_SOURCE 500
 #include <stdio.h>
 #include <stdlib.h>
 #include <time.h> /* 'nanosleep' */