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I am porting some Unix code into Windows Visual Studio 2010. I have run into the following line

gmtime_r(&now, &tm_time);

I found that gmtime_r() is a standard Unix function, but I am hoping to find the Windows equivalent. I found quite a few gmtime functions in time.h, but I am having trouble finding which one is equivalent, if it even exists. Could someone point me in the right direction?

Mr.C64
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Jorel Estrada
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1 Answers1

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gmtime_r() is the thread-safe version of gmtime(). The MSVC implementation of gmtime() is already thread safe, the returned struct tm* is allocated in thread-local storage.

That doesn't make it immune from trouble if the function is called multiple times on the same thread and the returned pointer is stored. You can use gmtime_s() instead. Closest to gmtime_r() but with the arguments reversed ;)

Hans Passant
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