diff --git a/src/proto.h b/src/proto.h
index ccd471d..cbd5c9f 100644
--- a/src/proto.h
+++ b/src/proto.h
@@ -61,14 +61,18 @@ int msgQueueElemDelete(msgQueueElemId queueElemId);
 void *msgQueueElemOpen(msgQueueElemId queueElemId);
 /* queueInit.c */
 msgQueue *queueInit(msgSpaceId externId, int queueIdx);
-/* queueLock.c */
-int queueLock(msgSpaceId externId, int queueIdx);
 /* queueOpen.c */
 void *msgQueueOpen(msgQueueId queueId);
+/* queueProtLock.c */
+int queueProtLock(msgSpaceId externId, int queueIdx);
+/* queueProtUnlock.c */
+int queueProtUnlock(msgSpaceId externId, int queueIdx);
+/* queueReadLock.c */
+int queueReadLock(msgSpaceId externId, int queueIdx);
+/* queueReadUnlock.c */
+int queueReadUnlock(msgSpaceId externId, int queueIdx);
 /* queueRem.c */
 int msgQueueElemRem(msgQueue *queue, msgQueueElemId oldElemId);
-/* queueUnlock.c */
-int queueUnlock(msgSpaceId externId, int queueIdx);
 /* spaceCreate.c */
 msgSpace *msgSpaceCreate(msgSpaceId externId, int queueNb, int poolNb, msgPool *poolInfos);
 /* spaceDelete.c */
diff --git a/src/queueProtLock.c b/src/queueProtLock.c
index 393909f..a80405c 100644
--- a/src/queueProtLock.c
+++ b/src/queueProtLock.c
@@ -1,11 +1,11 @@
 #include "libnazgul.h"
 #include "ids.h"
 
-int queueLock(msgSpaceId externId,int queueIdx){
+int queueProtLock(msgSpaceId externId,int queueIdx){
   sem_t * queueSemFd;
   msgQueueSemId queueSemId;
 
-  msgQueueSemIdIntern(queueSemId,externId,queueIdx);
+  msgQueueProtSemIdIntern(queueSemId,externId,queueIdx);
   queueSemFd=sem_open(queueSemId,O_CREAT|O_EXCL,SEM_DEFAULT_MODE,1);
   if(queueSemFd==SEM_FAILED){
 	NZG_ERROR("sem_open",queueSemId);
diff --git a/src/queueProtUnlock.c b/src/queueProtUnlock.c
index 0306195..bebe704 100644
--- a/src/queueProtUnlock.c
+++ b/src/queueProtUnlock.c
@@ -1,11 +1,11 @@
 #include "libnazgul.h"
 #include "ids.h"
 
-int queueUnlock(msgSpaceId externId,int queueIdx){
+int queueProtUnlock(msgSpaceId externId,int queueIdx){
  sem_t * queueSemFd;
   msgQueueSemId queueSemId;
 
-  msgQueueSemIdIntern(queueSemId,externId,queueIdx);
+  msgQueueProtSemIdIntern(queueSemId,externId,queueIdx);
   queueSemFd=sem_open(queueSemId,O_CREAT|O_EXCL,SEM_DEFAULT_MODE,1);
   if(queueSemFd==SEM_FAILED){
 	NZG_ERROR("sem_open",queueSemId);
diff --git a/src/queueReadLock.c b/src/queueReadLock.c
new file mode 100644
index 0000000..24a9ece
--- /dev/null
+++ b/src/queueReadLock.c
@@ -0,0 +1,26 @@
+#include "libnazgul.h"
+#include "ids.h"
+
+int queueReadLock(msgSpaceId externId,int queueIdx){
+  sem_t * queueSemFd;
+  msgQueueSemId queueSemId;
+
+  msgQueueReadSemIdIntern(queueSemId,externId,queueIdx);
+  queueSemFd=sem_open(queueSemId,O_CREAT|O_EXCL,SEM_DEFAULT_MODE,1);
+  if(queueSemFd==SEM_FAILED){
+	NZG_ERROR("sem_open",queueSemId);
+	goto ERROR;
+  }
+
+  if(sem_wait(queueSemFd)==-1){
+	NZG_ERROR("sem_wait",queueSemId);
+	goto ERROR;
+  }
+
+  sem_close(queueSemFd);
+
+  return 0;
+ERROR:
+  return -1; 
+}
+
diff --git a/src/queueReadUnlock.c b/src/queueReadUnlock.c
new file mode 100644
index 0000000..cb05b02
--- /dev/null
+++ b/src/queueReadUnlock.c
@@ -0,0 +1,26 @@
+#include "libnazgul.h"
+#include "ids.h"
+
+int queueReadUnlock(msgSpaceId externId,int queueIdx){
+ sem_t * queueSemFd;
+  msgQueueSemId queueSemId;
+
+  msgQueueReadSemIdIntern(queueSemId,externId,queueIdx);
+  queueSemFd=sem_open(queueSemId,O_CREAT|O_EXCL,SEM_DEFAULT_MODE,1);
+  if(queueSemFd==SEM_FAILED){
+	NZG_ERROR("sem_open",queueSemId);
+	goto ERROR;
+  }
+
+  if(sem_post(queueSemFd)==-1){
+	NZG_ERROR("sem_post",queueSemId);
+	goto ERROR;
+  }
+
+  sem_close(queueSemFd);
+
+  return 0;
+ERROR:
+  return -1;
+}
+