How to disallow logout

[Aryeh Friedman]

I have a directory that must not exist on logout and rm -rf is not
sufficent to do it because the contents need to be processed by our
version control system.   The real life scenario is our version
control system stores the repo for a given project encrypted but for
techinical reasons it needs to keep the checkouted files in plain text
(they are all in the same dir) and I want to *NEVER* have the plain
text checkouted files in my dir when I logout, *BUT* instead of just
deleting it I need to check them in...  so how do I make my .logout so
if the file exists it will not exit and give a error saying that dir
is still there? (minor but unimportant side effect of the version
control system is the dir will have a different name everytime it is
made but always the same prefix)