string - Can I read any readable valid memory location via a (unsigned) char* in C++? -



string - Can I read any readable valid memory location via a (unsigned) char* in C++? -

my search foo seems lacking today.

i know if legal according std c++ inspect "any" memory location via (unsigned(?)) char*. any location mean valid address of object or array (or within array) within program.

by way of example:

void passanyobjectorarrayorsomethingelsevalid(void* pobj) { unsigned char* pmemory = static_cast<unsigned char*>(pobj) mytypeidentifyier x = trytofigureoutwhatthisis(pmemory); }

disclaimer: question purely academical. not intend set production code! legal mean if it's legal according standard, if work on 100% of implementations. (not on x86 or mutual hardware.)

sub-question: static_cast right tool void* address char* pointer?

c++ assumes strict aliasing, means 2 pointers of fundamentally different type not alias same value.

however, correctly pointed out bdonlan, standard makes exception char , unsigned char pointers.

thus, in general undefined behaviour pointer type read any deliberate address (which might type), particular case of unsigned char in question allowed (iso 14882:2003 3.10(15)).

static_cast compile-time type checking, unlikely work. in such case, want reinterpret_cast.

c++ string pointers void-pointers memory-access

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