Modifying const variablesThis tip submitted by Wiro Sableng on 2006-01-30 01:43:11. It has been viewed 12368 times.Rating of 5.8 with 103 votes Warning: you almost never want to do this! But it is useful to know that it is possible--yes, a variable declared const can be modified in a variety of ways. Here is one of them, that demonstrates the power (and danger) of pointers.
int main (void)
{
/* I assume long is 4 bytes */
const long num = 0xabcd1234;
printf("%lx\n", num);
/* change the first byte */
((unsigned char *)&num)[0] = 0xaa;
printf("%lx\n", num);
return(0);
}
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