diff --git a/src/ids.c b/src/ids.c
index 790600d..4adc693 100644
--- a/src/ids.c
+++ b/src/ids.c
@@ -87,7 +87,7 @@ int msgBufferInfoTabIdIntern(
   return 0;
 }
 
-int msgQueueSemIdIntern(
+int msgQueueProtSemIdIntern(
 	msgQueueSemId dest,
 	msgSpaceId externId, 
 	int queueIdx){
@@ -95,9 +95,24 @@ int msgQueueSemIdIntern(
 	return -1;
   }
 #ifdef _NZG_REALFILEID
-  sprintf(dest,"/tmp/nzgQueue-%s-%d",(char *)externId,queueIdx);
+  sprintf(dest,"/tmp/nzgQueueProtSem-%s-%d",(char *)externId,queueIdx);
 #else
-  sprintf(dest,"/nzgQueue-%s-%d",(char *)externId,queueIdx);
+  sprintf(dest,"/nzgQueueProtSem-%s-%d",(char *)externId,queueIdx);
+#endif
+  return 0;
+}
+
+int msgQueueReadSemIdIntern(
+	msgQueueSemId dest,
+	msgSpaceId externId, 
+	int queueIdx){
+  if (strlen(externId)>MSGSPACE_ID_LEN){
+	return -1;
+  }
+#ifdef _NZG_REALFILEID
+  sprintf(dest,"/tmp/nzgQueueReadSem-%s-%d",(char *)externId,queueIdx);
+#else
+  sprintf(dest,"/nzgQueueReadSem-%s-%d",(char *)externId,queueIdx);
 #endif
   return 0;
 }
diff --git a/src/proto.h b/src/proto.h
index ecbd732..ccd471d 100644
--- a/src/proto.h
+++ b/src/proto.h
@@ -26,7 +26,8 @@ int msgPoolSemIdIntern(msgPoolSemId destSemId, const msgSpaceId srcPoolId, int p
 int msgPoolDataIdIntern(msgPoolDataTabId dest, const msgSpaceId src);
 int msgPoolIdIntern(msgPoolId dest, msgPoolId src, int num);
 int msgBufferInfoTabIdIntern(msgBufferInfoTabId dest, msgSpaceId src, int num);
-int msgQueueSemIdIntern(msgQueueSemId dest, msgSpaceId externId, int queueIdx);
+int msgQueueProtSemIdIntern(msgQueueSemId dest, msgSpaceId externId, int queueIdx);
+int msgQueueReadSemIdIntern(msgQueueSemId dest, msgSpaceId externId, int queueIdx);
 int msgQueueIdIntern(msgQueueId dest, msgSpaceId externId, int queueIdx);
 int msgQueueElemIdIntern(msgQueueElemId dest, msgQueueId src, int counter);
 int spaceListElemIdIntern(msgSpaceListElemId elemListId, msgSpaceId externId);
diff --git a/src/queueInit.c b/src/queueInit.c
index a156388..13d7fb7 100644
--- a/src/queueInit.c
+++ b/src/queueInit.c
@@ -4,11 +4,38 @@
 msgQueue * queueInit(msgSpaceId externId, int queueIdx) {
 	int queueFd;
 	msgQueue * queue;
-	sem_t * semaphore;
+	sem_t * semProtectFd;
+	msgQueueSemId queueSemProtectId;
+	sem_t * semReadableFd;
+	msgQueueSemId queueSemReadableId;
 	msgQueueId queueId;
 
 	queue = NULL;
+
+	msgQueueProtSemIdIntern(queueSemProtectId,externId,queueIdx);
+	msgQueueReadSemIdIntern(queueSemReadableId,externId,queueIdx);
+ 
+	// creation du semaphore de lecture 
+	semReadableFd = sem_open(queueSemReadableId, 
+		O_CREAT|O_EXCL, SEM_DEFAULT_MODE, 0);
+	if(semReadableFd == SEM_FAILED) {
+	  NZG_ERROR("sem_open", queueSemReadableId);
+	  goto ERROR;
+	}
 	
+	// creation du semaphore de protection
+	semProtectFd = sem_open(queueSemProtectId, 
+		O_CREAT|O_EXCL, SEM_DEFAULT_MODE, 1);
+	if(semProtectFd == SEM_FAILED) {
+	  NZG_ERROR("sem_open", queueSemProtectId);
+	  goto ERROR;
+	}
+
+	if(sem_wait(semProtectFd)==-1){
+	  NZG_ERROR("sem_wait",queueSemProtectId);
+	  goto ERROR;
+	}
+
 	if(msgQueueIdIntern(queueId, externId, queueIdx) < 0) {
 		return NULL;
 	}
@@ -32,25 +59,13 @@ msgQueue * queueInit(msgSpaceId externId, int queueIdx) {
 	strcpy(queue->tailId,queue->id);
 
 
-	
-	// creation du semaphore
-	semaphore = sem_open(queueId, O_CREAT|O_EXCL, SEM_DEFAULT_MODE, 1);
-	if(semaphore == SEM_FAILED) {
-		NZG_ERROR("sem_open", queueId);
-		goto ERROR;
-	}
-
-if(sem_wait(semaphore)==-1){
-	NZG_ERROR("sem_wait",queueId);
-	goto ERROR;
-  }
 
 	/* on ferme tout ce qu'il faut */
-	sem_close(semaphore);
+	sem_close(semProtectFd);
 	close(queueFd);
-	
+
 	return queue;
 ERROR:
 	return NULL;
-	
+
 }