Windows executable got executed on my linux - c++

Question

I wrote a simple code and compiled using g++ in linux in .exe format, suprisingly it got executed in my linux terminal. Can u say the reason for this ? Can linux terminal execute machine code in any format ? Can I run the same in windows ?
Code :
#include<iostream>
using namespace std;
int main(){
cout<<"Hello World !"<<endl;
return 0;
}
Compile code:
g++ main.cpp -o program.exe
OS: Linux Mint 20 Cinnamon.
I execute by typing ./program.exe

Answer 1

Q: I wrote a simple code and compiled using g++ in linux in .exe format, suprisingly it got executed in my linux terminal
A: There's nothing "surprising". I assume you compiled it under Linux? So why shouldn't you be able to run it under Unix?
Q: Will an .exe I build on Windows run on Linux (if I copied the binary)? A: Short answer: No.
Longer answer: you can install Wine to run Windows applications on Linux.
Q: Will an .exe I build on Ubuntu run on Windows? A: No.
Q: Does an executable I build on Ubuntu need to have the suffix .exe? A: No. File suffixes are irrelevant.
Q: Does an executable I build on Windows need to have the suffix .exe? A: Yes.
To answer your additional questions:
There are many reasons why an .exe built for one platform cannot load or run on a different platform.
Sam Varshavchik put it well:
It's for the same reason a radiator for your Toyota won't fit into a
Dodge
More to the point, an "executable image" is much more than just "the machine code".
An .exe is an example of "executable images". They come in many different formats: https://en.wikipedia.org/wiki/Category:Executable_file_formats. Most of these formats are platform-specific.
Any image must be loaded by the operating system in order to become a running process. This, too, is platform-specific.
The running process will need resources like file I/O , memory and shared libraries, which are also platform-specific.
I hope that helps...

Answer 2

Since you compiled the code using g++ on Linux, you should be able to run it on Linux but it won't work on Windows because the binary executable is compiled for Linux.
On Windows, .exe is the extension of the executable file but the binary code must be compiled for Windows so that it can run. On Linux, you can use any extension, .mp4 or anything and it will still run when typing ./program.mp4 in terminal.