diff --git a/src/libCom/osi/os/posix/osdSem.c b/src/libCom/osi/os/posix/osdSem.c
index 0873cf112..83e786557 100644
--- a/src/libCom/osi/os/posix/osdSem.c
+++ b/src/libCom/osi/os/posix/osdSem.c
@@ -121,6 +121,7 @@ semTakeStatus semBinaryTake(semBinaryId id)
     binary *pbinary = (binary *)id;
     int   status;
 
+    if(!pbinary) return(semTakeError);
     status = pthread_mutex_lock(&pbinary->mutex);
     checkStatusQuit(status,"pthread_mutex_lock","semBinaryTake");
     if(!pbinary->isFull) {
@@ -234,6 +235,7 @@ semTakeStatus semMutexTake(semMutexId id)
     pthread_t tid = pthread_self();
     int status;
 
+    if(!pmutex || !tid) return(semTakeError);
     status = pthread_mutex_lock(&pmutex->lock);
     checkStatusQuit(status,"pthread_mutex_lock","semMutexTake");
     while(pmutex->owned && !pthread_equal(pmutex->ownerTid,tid))
diff --git a/src/libCom/osi/os/posix/osdThread.c b/src/libCom/osi/os/posix/osdThread.c
index 698469436..519a69583 100644
--- a/src/libCom/osi/os/posix/osdThread.c
+++ b/src/libCom/osi/os/posix/osdThread.c
@@ -253,7 +253,12 @@ void threadInit(void)
 /* threadOnce is a macro that calls threadOnceOsd */
 void threadOnceOsd(threadOnceId *id, void (*func)(void *), void *arg)
 {
-    semMutexMustTake(onceMutex);
+
+    if(semMutexTake(onceMutex) != semTakeOK) {
+        fprintf(stderr,"threadOnceOsd semMutexTake failed.\n");
+        fprintf(stderr,"Did you call threadInit? Program exiting\n");
+        exit(-1);
+    }
     if (*id == 0) { /*  0 => first call */
     	*id = -1;   /* -1 => func() active */
     	func(arg);