Added all changes from old 4.0 version:

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pstack/pstacktrace.h

@@ -0,0 +1,24 @@
+/* $Header$ */
+
+/*
+ * Debugging macros.
+ */
+
+#ifndef	pstacktrace_h_
+#define	pstacktrace_h_
+
+#define	PSTACK_DEBUG 1
+#undef PSTACK_DEBUG
+
+#ifdef PSTACK_DEBUG
+#	define	TRACE_PUTC(a)		putc a
+#	define	TRACE_FPUTS(a)		fputs a
+#	define	TRACE_FPRINTF(a)	fprintf a
+#else /* PSTACK_DEBUG */
+#	define	TRACE_PUTC(a)		(void)0
+#	define	TRACE_FPUTS(a)		(void)0
+#	define	TRACE_FPRINTF(a)	(void)0
+#endif /* !PSTACK_DEBUG */
+
+#endif /* pstacktrace_h_ */
+