Thread: Need help with .exe file ??

Originally Posted by Gaurav Singh

After Compiling an Error Free C Program we get an .exe file. I have Few Doubts considering this .EXE file !!

1. is it true that generated .exe file contains only machine code ??

No. It also conatins constant data, resource information and variable mapping.

2. if it is in machine code then Can we run this file at any System ??

No. A windows program will run on any windows system. A linux program will run on any linux system.
But, no, you don't get to directly execute windows proggies on linux or visa versa.

The last time you asked this the conversation devolved into a confusing blather about emulators and such...
Believe me... the answer is NO.

3. Suppose I write a program in C to print my name and then I copy my .exe file into a blank CD. After Removing my HD from my Computer if I boot my PC with this CD then Is it true that my .exe file will be executed by BIOS ????

ABSOLUTELY NOT! And thank goodness for that!

Consider how many problems that would cause.

I'm not really very sure what your trying to do. To run your code just after the bootup would be quite difficult but not impossible. When you initialise/boot your system the first pieces of code will be executed such as ResetCode, Hardware initialisation and then startup code. The tricky part here to write these code specially the startup code would be quite challenging. The reason why I say that is because you need to understand your hardware before you can write on of those modules. A startup is effectively a collection of assembly code, which enabled you run your high-level code. Taking C as an example, to run a C code, you need a stack allocated in your memory. The startup code

1. Disables all the Interrupts
2. Copy any initialised data from ROM to RAM
3. Zero the uninitialized data area
4. Allocate space for and initialise the stack
5. Initialise the processor's stack pointer

And then finally call main (which would eventually be your .exe file). Startup code is usually names startup.asm.

Might be slightly different with the PC's. But the above strategy applies for almost all embedded systems

ssharish.