What does _mingw.h header file do?

Question

While I was solving a program in C++, I came across this library _mingw.h, and got curious as to what its use is. From the name I guessed it has something to do with the compiler.

Answer 1

What does _mingw.h header file do?

In general, it does same thing that all headers do. Headers contain declarations.

Judging by the name, it might be part of the MinGW project. More accurate guess requires context about where you found that header. Regardless, including it would likely make your program dependent on using that specific toolchain.

Note that if the header is undocumented, then you should not rely on the anything declared within it because there won't be any guarantee that the header would remain the same across different versions. Nor should you rely on the file existing. Therefore it will be quite rare for it to be useful to know what is declared in such header. Nevertheless, you can open the file to find out what it declares.