diff --git a/src/libCom/osi/os/posix/osdMutex.c b/src/libCom/osi/os/posix/osdMutex.c
index e3f5470dc..08eda1002 100644
--- a/src/libCom/osi/os/posix/osdMutex.c
+++ b/src/libCom/osi/os/posix/osdMutex.c
@@ -240,9 +240,7 @@ void epicsMutexOsdShow(struct epicsMutexOSD * pmutex, unsigned int level)
  *   // if another thread performing the test above sees the 'invalid' or already
  *   // 'our' TID. 
  *   atomic_store(&m->owner, pthread_self(), relaxed);
- *   // mutex_lock has 'acquire' semantics, i.e., the
- *   // final count-- that happened in another thread is guaranteed
- *   // to have completed
+ *   // 'count' is only ever accessed with 'mtx' held
  *   m->count = 1;
  * }
  *
diff --git a/src/libCom/osi/os/posix/osdMutex.h b/src/libCom/osi/os/posix/osdMutex.h
index c0c9d7e21..e88afab6b 100644
--- a/src/libCom/osi/os/posix/osdMutex.h
+++ b/src/libCom/osi/os/posix/osdMutex.h
@@ -8,7 +8,7 @@
 * in file LICENSE that is included with this distribution. 
 \*************************************************************************/
 #ifndef osdMutexh
-#define osdTMutexh
+#define osdMutexh
 
 #include <pthread.h>