diff --git a/src/nzg_iface.h b/src/nzg_iface.h
index 9462421..b2fde63 100644
--- a/src/nzg_iface.h
+++ b/src/nzg_iface.h
@@ -2,6 +2,9 @@
 #define _NZG_IFACE 1
 
 #include "nzg_global.h"
+
+typedef enum { true=1, false=0} bool;
+
 typedef char msgSpaceId[MSGSPACE_ID_LEN];
 
 typedef char msgSpaceListId[4*MSGSPACE_ID_LEN];
@@ -24,11 +27,12 @@ typedef struct MsgPoolData {
   int bufferNb;
   int bufferSize;
   int allocDispBuffer;
-  int allocOverload;
+  bool allocOverload;
 } msgPoolData;
 
 /* TODO: queueId */
 
+
 typedef struct MsgSpace {
   msgSpaceId id;
   int poolNb;