Yes, none of those things are "thread safe". All of them are "iThread safe". And "Perl protects its internals with internal locking" isn't very accurate. Perl protects its internals by making full copies of its internals (the interpreter state and all data) -- emulating fork but less efficiently.

The major thing related to iThreads that Perl protects with locking is the hidden "real value" of a threads::shared variable.