Mutex between two or more process

[tbscope]

Is this what you're looking for?
http://doc.qt.nokia.com/4.7/qsharedmemory.html

[bred]

Is this what you're looking for?
http://doc.qt.nokia.com/4.7/qsharedmemory.html

Yes and No.

No: I'm searching for something with the tryLock() member function.
The tryLock() function exits immediately by returning false if the Mutex is locked.

Yes: It's shared between two or more process.