Document optional trace-regex in rec_control help

To clear tracing, rec_control trage-regex should be called without a regex parameter. Document in rec_control help.

diff --git a/pdns/rec_channel_rec.cc b/pdns/rec_channel_rec.cc
index 47c1a59a8ba4b68e9d3519cae32386343d3a0664..d1444658d3ab1d80c7ed97bf77b81aaa482f6f70 100644 (file)
--- a/pdns/rec_channel_rec.cc
+++ b/pdns/rec_channel_rec.cc
@@ -638,7 +638,7 @@ string RecursorControlParser::getAnswer(const string& question, RecursorControlP
 "reload-lua-script [filename]     (re)load Lua script\n"
 "reload-zones                     reload all auth and forward zones\n"
 "set-minimum-ttl value            set mininum-ttl-override\n"
-"trace-regex regex                emit resolution trace for matching queries\n"
+"trace-regex [regex]              emit resolution trace for matching queries (empty regex to clear trace)\n"
 "top-remotes                      show top remotes\n"
 "unload-lua-script                unload Lua script\n"
 "wipe-cache domain0 [domain1] ..  wipe domain data from cache\n";