Difference between void main and int main? [duplic

Question

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• What should main() return in C and C++? 18 answers

Does it matter which way I declare my C++ programs?

Answer 1

The difference is one is the correct way to define main, and the other is not.

And yes, it does matter. Either

int main(int argc, char** argv)

or

int main()

are the proper definition of your main per the C++ spec.

void main(int argc, char** argv)

is not and was, IIRC, a perversity that came with older Microsoft's C++ compilers.

https://isocpp.org/wiki/faq/newbie#main-returns-int

Answer 2

If you're going by the spec, then you should always declare main returning an int.

In reality, though, most compilers will let you get away with either one, so the real difference is if you want / need to return a value to the shell.

Answer 3

The point is, C programs (and C++ the same) always (should?) return a success value or error code, so they should be declared that way.

Answer 4

Bjarne Stroustrup made this quite clear:

The definition void main() is not and never has been C++, nor has it even been C.

See reference.

Answer 5

You should use int main. Both the C and C++ standards specify that main should return a value.

Answer 6

For C++, only int is allowed. For C, C99 says only int is allowed. The prior standard allowed for a void return.

In short, always int.