diff --git a/src/as/asCa.h b/src/as/asCa.h
index d6eae833c..64ee20654 100644
--- a/src/as/asCa.h
+++ b/src/as/asCa.h
@@ -14,8 +14,17 @@ of this distribution.
 #define INCasCah
 
 #include "shareLib.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 epicsShareFunc void epicsShareAPI asCaStart(void);
 epicsShareFunc void epicsShareAPI asCaStop(void);
 epicsShareExtern int asCaDebug;
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif /*INCasCah*/