diff --git a/src/dcfg.c b/src/dcfg.c
index ecd1464..333e9f2 100644
--- a/src/dcfg.c
+++ b/src/dcfg.c
@@ -35,6 +35,8 @@
 
 #if DCFG_POSIX_SUPPORT
 #	define _POSIX_C_SOURCE 200809L
+#	define _XOPEN_SOURCE 500L
+#	define _BSD_SOURCE
 #else
 #	ifdef _POSIX_C_SOURCE
 #		undef _POSIX_C_SOURCE