Hi, I'm wondering why the VI below outputs different semaphore references. So far I assumed that they will be the same. Thanks!

The good old problem of all higher level object oriented languages like Java and C#. Should an object reference comparison return true or false if the references are different but pointing to the same object. The default is to compare the reference itself and hence return false for the isEqual() method. If you want a different behaviour you have to overwrite the class method isEqual() and do an explicit comparison of the relevant class private data or whatever it is your object contains. LabVIEW does this internally for the VI Server objects (but didn't always do that in the past). Not so for other refnum types however. I don't think that the object manager interface that is responsible for managing refnums actually supports a comparison method, so the Equal operator has to delegate to refnum specific methods in the case of VI Server refnums. Not a clean design, but after more than 35 years of development such inconsistencies are simply impossible to avoid. They tried an experiment in the early 90ies of last century to compile LabVIEW in C++. At that time the generated executable size was exploding because of that and with 4 to 8 MB of RAM being the standard in computers at that time it was simply not an option. So they stayed with C code for several more years before starting to develop all new features in C++ only.

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