Anubhav Hanjura wrote:
> Trying to print *ip as a character when I apply post increment operator
> gives me 'D' and for pre-increment it gives me a bus error. Why?
You are using a big-endian processor (e.g. 680x0), right?
> #include<stdio.h>
> int main()
> {
> char *c_array;
> int *ip;
> c_array = (char *)malloc(100);
> strcpy(c_array,"ABCDEFHIFGHIJKLMN");
> ip = (int *)(++c_array);
> return 0;
> }
The value of the expression:
*(int *)(c_array)
depends upon sizeof(int) and the processor's byte order:
32-bit little-endian: 0x44434241
32-bit big-endian: 0x41424344
64-bit little-endian: 0x4847464544434241
64-bit big-endian: 0x4142434445464748
Calling
printf("%c", *(int *)(c_array))
will display either 'A' (0x41), 'D' (0x44) or 'H' (0x48) depending
upon sizeof(int) and the processor's byte order.
Using pre-increment addressing will attempt to read a 32-bit value
from an odd address, which will cause a bus error on processors which
require aligned memory access (80x86 doesn't; AFAIK 680x0 does).
--
Glynn Clements <[EMAIL PROTECTED]>
