Re: advantage of using typedefs


Emmanuel Delahaye wrote:
> junky_fellow@xxxxxxxxxxx a écrit :
> > I wanted to know what advantage do we get by typedefs ? Why we did not
> > declare
> > offset simply as
> > long off_t;
>
> It's often a portability issue. Imagine you want a type that hold the
> biggest possible unsigned integer.
>
> You will have this in C90:
>
> typedef unsigned long biggest_int_t;
>
> and that on C99:
>
> typedef unsigned long long biggest_int_t;
>
> With the help of some smart macros and #ifxxx directives, After a simple
> recompile, the type will automagically be corrected after a simple
> recompile of the project/lib or whatever.
>

Thanx for your reply, Emmanuel. But if this is the case (ie we need
the biggest possible
unsigned integer to hold offset ) then why not declare
unsigned long long offset;
I believe unsigned long long should be highest possible integer type ?
Or am I wrong ?

Is there any other reason for doing that ?

.

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