c++ - Observe changes in QSharedMemory -


i have qsharedmemory prevent 2 processes of application running @ same time. process sets qsharedmemory "locked" when started. process b sets value "please come foreground".

is there easy way process observe changes in qsharedmemory, i.e. avoids implementing stupid pulling timer?

here are: qsystemsemaphore

like lighter counterpart qsemaphore, qsystemsemaphore can accessed multiple threads. unlike qsemaphore, qsystemsemaphore can accessed multiple processes.

like qsharedmemory, qsystemsemaphore uses key-based access method.


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