+/*
+ * If we have va_copy(), use it for assigning va_list's.
+ */
+#if defined(HAVE___VA_COPY)
+#define begin_va_copy(dst,src) __va_copy(dst, src)
+#define end_va_copy(dst) va_end(dst)
+#elif defined(va_copy) || defined(HAVE_VA_COPY)
+#define begin_va_copy(dst,src) va_copy(dst, src)
+#define end_va_copy(dst) va_end(dst)
+#else
+#define begin_va_copy(dst,src) (dst) = (src)
+#define end_va_copy(dst) /* nothing */
+#endif
+
+/*
+ * Either/both S_ISxxx and/or S_IFxxx are defined in sys/types.h; some systems
+ * lack one or the other.
+ */
+#ifndef S_ISDIR
+#define S_ISDIR(mode) ((mode & S_IFMT) == S_IFDIR)
+#endif
+
+#ifndef S_ISREG
+#define S_ISREG(mode) ((mode & S_IFMT) == S_IFREG)
+#endif
+