Fix C++ building

Author: Mygod

ancillary.h

@@ -31,6 +31,10 @@
 #ifndef ANCILLARY_H__
 #define ANCILLARY_H__
 
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 /***************************************************************************
  * Start of the readable part.
  ***************************************************************************/
@@ -120,4 +124,8 @@ ancil_recv_fd(int, int *);
  * Returns : -1 and errno in case of error, 0 in case of success.
  */
 
+#ifdef __cplusplus
+}
+#endif
+
 #endif /* ANCILLARY_H__ */