--- afdko/c/shared/include/tx_shared.h
+++ afdko/c/shared/include/tx_shared.h
@@ -86,6 +86,11 @@
 #define sig_UFO CTL_TAG('<', '?', 'x', 'm')
 /* Generate n-bit mask */
 #define N_BIT_MASK(n) (~(~0UL << (n)))
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 enum { MAX_VERSION_SIZE = 100 };
 
 typedef struct txCtx_ *txCtx; /* tx program context */
@@ -587,4 +592,8 @@
 void ttrReadFont(txCtx h, long origin, int iTTC);
 void ufoReadFont(txCtx h, long origin);
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif /* TX_SHARED_H */