Sharing between two Threads

When I create two instances of a Qthread derived class and run both threads.
Which area/space do they share now?

I know, that using static makes it possible. But without static variables?
Just the pure QThread-class with "normal" private variables.

I know its a bit stupid but,..all my tests showed my that they dont share anything.

Example1:
I counted on both instances an int var (private). No problem.

Example2:
I declared a var in run() and done sth with it on both threads...no problem.

So where do they share sth?

Threads share code and data space. Each thread has an own stack. QThread objects themselves don't share anything. If you declare a global variable, it will be visible by both threads. If you want to avoid that, you can use shared memory. In both cases you'll have to synchronize those threads (using a global mutex so you won't escape from globals or statics).

Ahh thats what I wanted to hear. :)
I know that the theory says threads share...but i was confused with qthreads.

In case of qthreads i must explicit share sth via global var, static var or shared mem.