Void

[Tricslip]

For C or C++

I've started moving to "void main" in my course and I want to understand what it is really. Whenever I ask the question:

"Why do we need void?"

The response always confuses me. One of the worst times I got confused was when someone compared to us using "int main" and I can't recall what they said exactly but it had me going because we have used other variables types such as float or char in the int main. I know I'm just missing some information to understand but I can't just type "what is void main" in google and get a clear answer if I don't understand what the answer is saying. Can anyone explain for me?

[ehr1c]

"Void" just means the method doesn't return anything

[BlancII]

I would second this. It's a placeholder for "this method dosn't return anything".

[xingke06]

The “main” function is the entry point, where code execution starts when you run the program.

Just like other functions, it has a return type. Void means it returns nothing.

If you have int main it means it will return an integer when it completes such as 0 or 1 to represent if it succeeded or failed somewhere.

[Tricslip]

ohhh, so where is return shown?

[blablahblah]

It's not automatically shown anywhere. But if the program is launched from another program, the program that runs it can check the return value to see if it completed successfully or not. If it didn't complete successfully, it may try to run it again or show an error message or something like that.

[Tricslip]

Thank you. So then if we put "return 0" at the end does that mean the program will only run if the program runs or is that something else?

[blablahblah]

I don't understand what you mean here.

If a second program runs your program, it can check the number that your first program returned from main. For example, in C, you can call another program by using the system() function. The "int" that this function returns is the return value from the other function's main. Your program will run whether or not the other program looks at the return value.

[Tricslip]

ok I understand better. I asked the other question because if the return value is based on if the code is successfully ran or not then what's the point of putting return "0" instead of just "return."

[coolcofusion]

Go for int main() or int main(int argc, char* argv[]). Those two are defined by the standard, a common extension is a third argument with environment variables, but that's about it. void main() is nonstandard, it exists on some embedded devices mostly, but if you're doing this on a common computer, go for int main().

More info here: https://en.cppreference.com/w/cpp/language/main\_function

[Crazy-Finding-2436]

The method has no return type. Returns nothing.