Not sure if this is actually useful, but I've been asked often enough

Not sure if this is actually useful, but I've been asked often enough
that I think it's probably worth mentioning. On the other hand, if
someone can't grep the source code for '20000', I'm not sure they should
be encouraged ... ;-)

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@918022 13f79535-47bb-0310-9956-ffa450edef68