Re: scratch_buffer and 'void *' pointer arithmetic

[Bruno Haible]

I wrote:
> struct scratch_buffer {
>   void *data;    /* Pointer to the beginning of the scratch area.  */
>   size_t length; /* Allocated space at the data pointer, in bytes.  */
>   ...
> };
> 
> it seems quite natural to do pointer arithmetic on 'data'. Namely, this will
> happen each time a scratch_buffer gets booked by several (not just one)
> pieces of memory.

Oops. scratch_buffer is not appropriate for this kind of use, as it does
not contain a 'size_t used;' field (like linebuffer does).

I was thinking at a combination between scratch_buffer and the 'alloca_used'
logic from glob.c. But this is beyond what scratch_buffer does.

Bruno