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Re: Casting a pointer to a structure

Marius Vollmer <mvo@zagadka.ping.de> writes:

>     struct env_funcs **ptr1 = ...;
>     struct m *ptr2 = (struct m *)ptr1;
> 
> Is this safe too?  How can this be safely generalized to
> non-zero-offset members?

Yes it is.  ANSI guarantees that a pointer to a structure
can be casted to a pointer to its first element and vice versa.

And I think this first element can also be a complex type (a structure
or union) but I am not sure.


Jost
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