Where does the returned value for 'main' function go?

Question

In C, a function always returns its value to the calling function and never to itself (if return type is not void). Like,

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Answer 1

This is completely OS-specific, but usually the OS invokes a program by

1. Setting up the program's address space,
2. Creating a record of the new process somewhere in the OS internals,
3. Launching its own custom function, which calls main and stores the return value in the OS internals.

The function I'm referring to in (3) is often a good old fashioned C function that just jumps into main so it can capture the return value from main as if it were an ordinary C function (which it in fact is). Afterwards, it stores that value somewhere in OS-land so that processes that need to read the return value can do so.

Hope this helps!