Why does Rust not have a return value in the main function, and how to return a value anyway?

Question

In Rust the main function is defined like this:

fn main() {

}

This function does not allow for a return value though. Why would a language not

Answer 1

As was noted by others, std::process::exit(code: i32) is the way to go here

More information about why is given in RFC 1011: Process Exit. Discussion about the RFC is in the pull request of the RFC.