[sane-devel] [patch] fix SANE_Device

[Frank Zago]

Oliver Rauch wrote:
> Am Sam, 2004-11-13 um 21.26 schrieb Frank Zago:
> 
> 
>>>I guess the idea was that the strings shouldn't be changed after the
>>>SANE-Device pointer is returned to the frontend.
>>
>>Thsi behaviour should be made clear in the doc. To me, const means something else.
>>Since this patch makes the variable from const to non-const, I don't think it 
>>will break anything.
>>
>>
>>>As far as I can see the trouble results from doing things like
>>>sane.name = strdup (...) and freeing those in sane_exit().
>>>
>>
>>That is correct. I think it's clear from the use of that field that the const 
>>creates more trouble than it solves.
> 
> 
> Hello Henning, hello Frank,
> 
> I think the const should not be changed because of two reasons:
> 
> 1) It makes sense to define it as const in the standard because
>    the frontend should not change anything in the struct that
>    is returned by the backend
> 2) It is part of the sane standard and it makes a lot of problems
>    to change the standard definitions
> 
> May be we need a second definition without the const in some cases,
> but the struct that is returned by the backend should contain const
> strings.
> 
> So when it is necessary then the routine that needs any non const
> strings has to create its own struct definition.
> 
> May be this second (non const) definition can be put in a helper file
> (sanei_???.h).
> 
> Oliver
> 
> 

So what about having an external definition for frontends, and one internal for 
backends?