* Added support for X11 modules.
* Makefile: change location of FORMS library.
* posixmodule.c: turn #if 0 into #ifdef MSDOS (stuff in unistd.h or not)
* Almost all .h files: added CPP magic to avoid duplicate inclusions and
  to support inclusion from C++.
diff --git a/Include/errcode.h b/Include/errcode.h
index 1439c7b..d2a2ac6 100644
--- a/Include/errcode.h
+++ b/Include/errcode.h
@@ -1,3 +1,9 @@
+#ifndef Py_ERRCODE_H
+#define Py_ERRCODE_H
+#ifdef __cplusplus
+extern "C" {
+#endif
+
 /***********************************************************
 Copyright 1991, 1992, 1993 by Stichting Mathematisch Centrum,
 Amsterdam, The Netherlands.
@@ -34,3 +40,8 @@
 #define E_NOMEM		15	/* Ran out of memory */
 #define E_DONE		16	/* Parsing complete */
 #define E_ERROR		17	/* Execution error */
+
+#ifdef __cplusplus
+}
+#endif
+#endif /* !Py_ERRCODE_H */