diff --git a/bthread.h b/bthread.h
index 57a0c49..27c724b 100644
--- a/bthread.h
+++ b/bthread.h
@@ -24,8 +24,13 @@
 # define PTHREAD_CANCEL_DEFERRED     0x00000000
 
 #define PTHREAD_CANCELED ((void *) -1)
-
+#if defined(__cplusplus)
+extern "C" {
+#endif
 int pthread_setcancelstate (int , int *);
 int pthread_setcanceltype (int , int *);
 void pthread_testcancel (void);
 int pthread_cancel (pthread_t t);
+#if defined(__cplusplus)
+} // extern "C"
+#endif