How does this code work:
int a = 1;
int b = 10;
a |= b;
how the a |= b; works? Seems like |= is not an operator in C?
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MOHAMED
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user2131316
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It is same as : `a = a | b`; – Alok Save Apr 22 '13 at 15:25
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This is an elementary question, answerable by reading any decent C book or tutorial. (Operator symbols typically appear at the beginning of the index, before 'A'). – Keith Thompson Apr 22 '13 at 15:26
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Don't downvote for no reason, please. A simple question isn't necessarily a bad question. – Neil Apr 22 '13 at 15:29
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Does this answer your question? [What does the |= operator mean in C++?](https://stackoverflow.com/questions/4217762/what-does-the-operator-mean-in-c) – Josh Correia Aug 21 '23 at 20:53
7 Answers
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It works like the | + the = operator, in a similar way as += works.
It is equivalent as
a = a|b;
I suggest you to read this article about operators: http://en.wikipedia.org/wiki/Operators_in_C_and_C%2B%2B#Bitwise_operators Ans this one about bitwise operation http://en.wikipedia.org/wiki/Bitwise_operation
Antzi
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Following the pattern of, for example, +=:
a |= b;
// Means the same thing as:
a = a | b;
That is, any bits that are set in either a or b shall be set in a, and those set in neither shall not be set in a.
cdhowie
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That's the "bitwise or" equal. It follows in the pattern of the plus equal +=, minus equal -=, etc.
a |= b; is the same as a = a | b;
Mr. Llama
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"Bitwise or equal" is not the name of this operator. You are confusing it with `>=` et al., which are comparison operators. `|=` is not a comparison operator. – cdhowie Apr 22 '13 at 15:26
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The phrasing is a bit odd, so I'll edit it. I mean "bitwise or" equal. Kinda like "plus" equal. – Mr. Llama Apr 22 '13 at 15:27
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Ah, yes, I see what you mean now. The "or" does make it difficult to construct an operator name with the same pattern as plus-equal. – cdhowie Apr 22 '13 at 15:28
