diff --git a/drivers/net/util.c b/drivers/net/util.c
index 073deee4..c243dc21 100644
--- a/drivers/net/util.c
+++ b/drivers/net/util.c
@@ -1,6 +1,12 @@
 #include "util.h"
 
 
+__inline int isprint(char e)
+{
+	if (e < 0x30 || e > 0x80)
+		return false;
+}
+
 // hex_dumb display network packets in a good way
 void hex_dump(unsigned n, const unsigned char* buf)
 {