XER support
diff --git a/skeletons/asn_system.h b/skeletons/asn_system.h
new file mode 100644
index 0000000..ee64a0c
--- /dev/null
+++ b/skeletons/asn_system.h
@@ -0,0 +1,65 @@
+/*-
+ * Copyright (c) 2003, 2004 Lev Walkin <vlm@lionet.info>. All rights reserved.
+ * Redistribution and modifications are permitted subject to BSD license.
+ */
+/*
+ * Miscellaneous system-dependent types.
+ */
+#ifndef _ASN_SYSTEM_H_
+#define _ASN_SYSTEM_H_
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <stdio.h> /* For snprintf(3) */
+#include <stdlib.h> /* For *alloc(3) */
+#include <string.h> /* For memcpy(3) */
+#include <sys/types.h> /* For size_t */
+#include <stdarg.h> /* For va_start */
+#include <stddef.h> /* for offsetof and ptrdiff_t */
+
+#include <inttypes.h> /* C99 specifies this file */
+
+#if defined(sun)
+#include <ieeefp.h> /* for finite(3) */
+#endif
+
+/*
+ * 1. Earlier FreeBSD version didn't have <stdint.h>,
+ * but <inttypes.h> was present.
+ * 2. Sun Solaris requires <alloca.h> for alloca(3),
+ * but does not have <stdint.h>.
+ */
+#if (!defined(__FreeBSD__) || !defined(_SYS_INTSYSTEM_H_))
+#if defined(sun)
+#include <alloca.h> /* For alloca(3) */
+#else
+#include <stdint.h> /* SUSv2+ and C99 specify this file, for uintXX_t */
+#endif
+#endif
+
+#ifdef WIN32
+#define snprintf _snprintf
+#define vsnprintf _vsnprintf
+#define alloca(size) _alloca(size)
+#endif /* WIN32 */
+
+#ifndef __GNUC__
+#define __attribute__(ignore)
+#endif
+
+#ifndef offsetof /* If not defined by <stddef.h> */
+#define offsetof(s, m) ((ptrdiff_t)&(((s *)0)->m) - (ptrdiff_t)((s *)0))
+#endif /* offsetof */
+
+#ifndef MIN /* Suitable for comparing primitive types (integers) */
+#if defined(__GNUC__)
+#define MIN(a,b) ({ __typeof a _a = a; __typeof b _b = b; \
+ ((_a)<(_b)?(_a):(_b)); })
+#else /* !__GNUC__ */
+#define MIN(a,b) ((a)<(b)?(a):(b)) /* Unsafe variant */
+#endif /* __GNUC__ */
+#endif /* MIN */
+
+#endif /* _ASN_SYSTEM_H_ */