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How to access or modify the const variable in c ?

Answer Posted / gaurav bhandarkar

Author : Gaurav M. Bhandarkar
Yes u can modify constants...

Theory:
const int z = 420; // z is constant
&z (address of constant)
z (value of constant)

imp:
*(int*)((char*)&(*((char*)&z+1))-1) is
a unity/identity pointer operation resulting in z
That is:-
printf("%d | %d",*(int*)((char*)&(*((char*)&z+1))-1),z);
OUTPUT: 420 | 420

code:

const int z = 420;

printf("%d | %d\n",*(int*)((char*)&(*((char*)&z+1))-1),z);
//o-p 420 | 420


*((char *)&z+1) = 21; //corrupting the constant


printf("%d | %d",*(int*)((char*)&(*((char*)&z+1))-1),z);
//o-p 5540 | 420

___
The 2 similar printf's(check they are same)
o/p different values for same "z"
which is a constant!
thus the constant was corrupted!

Is This Answer Correct ?    53 Yes 3 No



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