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Is variable++ 1 atomic action?

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Join Date: May 2005

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Is variable++ 1 atomic action?

May 26th, 2005

Hi everyone, just wondering if anyone knows if any variable++ would be classed as 1 atomic action? Thanks guys

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Join Date: May 2005

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Re: Is variable++ 1 atomic action?

May 27th, 2005

In general, no.

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Re: Is variable++ 1 atomic action?

May 27th, 2005

Thanks Dogtree for replying, I had this question in an exam, true or false, I don't know anything about it though, would you be able to explain why it is false, that would be great

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Re: Is variable++ 1 atomic action?

May 27th, 2005

By its definition, the postfix increment operator has to use temporary storage so that it can return the pre-incremented value. You can think of it like this:

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operator++
  temp = self;
  self = self + 1;
  return temp;

Optimizations can make it close to atomic for all cases of built-in types, or atomic for some cases of some built-in types, but in the general case, it's not gonna happen.