Re: [CODE] Confuzius about pointers and stuff

From: Peter Ajamian (
Date: 10/02/00

The Merciless Lord of Everything wrote:
> char *to_vict = NULL, *to_room = NULL;
> Now, I remember having a discussion some time back with PjD about
> this. And as far as I recall, this is a pointer which has "some" space in
> it, but not very much (sorry, it's late and I should really be sleeping by
> now :) if I recall corcretly it was assigned with 4 bytes or something in
> that order.
The above line will not allocate any space for type char.  what it does
is it creates a pointer of type char and sets it to NULL, the only space
allocated is that required for the pointer itself (which is
implementation-defined).  You would do the above if you wanted to either
allocate your own space (with malloc or CREATE) and assign the p[ointer
to it so you can keep track of it, or if you want to have an extra
pointer that you can use to manipulate data in existing variables.

> Okay, the messages in magic.c isn't really that big, and so this may not
> cause any problem for those. But wouldn't it be more correct to do
> something in the lines of
> char to_victim[MAX_STRING_LENGTH] = "";
> char to_char[MAX_STRING_LENGTH] = "";
That all depends, if it has survived 6 bpls like this (and without
double checking myself), I would imagine that it is correct as-is.

The above will actually allocate space (of MAX_STRING_LENGTH chars) and
create a variable which points to it.  Note that unlike a pointer you
cannot change what this variable points to, it is constant and will
always point to the same area of memory.

Regards, Peter

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