cast'ing unions

[David Riches]

Here's a posting for a friend, replies to ME please:-
------
I have a question regarding the "union" construct in the C programming language
which I need answering urgently.

Consider the following union construct :

union
{
   int i ;
   float f ;
   char* c ;
}
UNION ;

...
...
UNION u ;
u.i = 1 ;


Is it possible in C to typecast from an instance of the union to a variable
having the same type as one of the component fields of the union :

ie float num = (float) u ;

I tried the above but got compiler errors. Am I doing the typecast wrong,
or do I need to use another method to achieve the above, or is it not
possible to do the typecast directly ??

   Dave Riches
   PSS:    dsr at stl.stc.co.uk
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