Question

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What is the difference between _tmain() and main() in C++?

How the void main(…), int main(..) and int _tmain() differs. They all are single entry and single exit systems. But in what situations we use these start-up functions?

Answer 1

void main() is invalid; the C++ standard requires main to return int. Some compilers let you get away with it.

int main() is one of the two standard forms. The other is int main(int argc, char *argv[]), which can be used to receive command-line arguments. Implementations may permit other forms, but are not required to — but all such forms must return int.

int _tmain() is specific to Microsoft.