diff --git a/src/Makefile b/src/Makefile
index 1dbc0cc..984ff85 100644
--- a/src/Makefile
+++ b/src/Makefile
@@ -3,7 +3,7 @@ PREFIX	= /usr/local
 DESTDIR	=
 BINDIR	= $(PREFIX)/bin
 CC	= cc
-CFLAGSF	= -W -Wall -ansi -I /System/Include
+CFLAGSF	= -W -Wall -ansi -I /System/Include -D_GNU_SOURCE
 CFLAGS	= -g
 LDFLAGSF= -L /System/Libraries -l System -l dl
 RM	= rm -f