Re: Help in c pointers

On 2006-02-28, Kenneth Brody <kenbrody@xxxxxxxxxxx> wrote:
"manochavishal@xxxxxxxxx" wrote:

HI

int *p;
*p = 4;

char * msg;
*msg = 'c';

printf("msg is %s",msg);

when i try to pass a value 4 to place what integer pointer p points to
it says seg fault

but for the char pointer it works fine.

Why this behaviour

Neither pointer has been initialized, and both assignments invoke UB. In
your particular case, the address in p happened to be invalid for an int,
and the address in msg happened to be valid for a char, and didn't cause
any noticable effect by overwriting that memory.

Incidentally, there's a third instance of undefined behavior here -
anyone know what it is?
.

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