Returns the current value of the thread local variable @key.
If the value has not yet been set in this thread, %NULL is returned. Values are never copied between threads (when a new thread is created, for example).
the thread-local value
See Implementation
Returns the current value of the thread local variable @key.
If the value has not yet been set in this thread, %NULL is returned. Values are never copied between threads (when a new thread is created, for example).