Hi... On Fri, May 27, 2011 at 13:44, sandeep kumar <coolsandyforyou@xxxxxxxxx> wrote: > > I want to start with the following question, > How a program could generate the memory addresses for its variables, when it > is about to run? first, linker will determine in which section and which offset (from the start of the program) the variables will be positioned. If it is a dynamic variable (one that ends up in stack), it will determined dynamically later according to stack position. later, loader will reposition those variables based on real memory address positioning. This is based on the information placed inside the binary (ELF header). Usually, it is followed strictly, but if it is PIE (Position Independent Executable), further flexible reposition is allowed based on certain policy. those address (for static variables) are then substituted into GOT (Global Offset Table), some kind of lookup table to determined address of variables (and function address too actually). for dynamic variable, usually simply using compiler generated code, it is sufficient to reference them. This is because they are referenced using relative offset against base address of frame (which is usually saved in esp or ebp in x86 arch) I hope I correctly describe it.... -- regards, Mulyadi Santosa Freelance Linux trainer and consultant blog: the-hydra.blogspot.com training: mulyaditraining.blogspot.com _______________________________________________ Kernelnewbies mailing list Kernelnewbies@xxxxxxxxxxxxxxxxx http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
