Document -k option as experimental
strace -k does not produce a reliable output on all supported
configurations yet, even basic strace-k.test is known to fail
on some of them.
* strace.c (usage): Document -k option as experimental.
* strace.1: Likewise.
* NEWS: Likewise.
diff --git a/NEWS b/NEWS
index 3347236..a311c34 100644
--- a/NEWS
+++ b/NEWS
@@ -6,7 +6,7 @@
added --enable-arm-oabi option to enable it at configure time.
* Improvements
- * Added -k option to print stack trace after each traced syscall.
+ * Added experimental -k option to print stack trace after each traced syscall.
* Added -w option to produce stats on syscall latency.
(addresses Debian bug #457497).
* Added ARC architecture support.