c++ - Program address range -

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when write simple program using c / c++ , what's address range get? mean, can point wherever want.. : 

void* ptr = (int*)0xffffffff;

where pointer point to? guess not real address in main memory "cover" address of program.

can explain me? what's address range (in windows example) when running own c program? can access other program's address range if want to?

thanks!

your program runs in virtual address space, , pointers point locations within virtual memory. no, cannot expect conjure pointer same numeric value 1 in program , have them both point same actual memory. on contrary, if program crash or otherwise misbehave (but beware: it's undefined behavior, happen , it's platform-dependent).


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