Was testing non-existence of file named 'foobar' -- but Parrot developers may very well have such a file lying around.  Generate file name from process ID instead.
Was testing non-existence of file named 'foobar' -- but Parrot developers may very well have such a file lying around.  Generate file name from process ID instead.

git-svn-id: 6e74a02f85675cec270f5d931b0f6998666294a3@29988 d31e2699-5ff4-0310-a27c-f18f2fbe73fe

ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot,ashgti/parrot