Re: how is the do loop in the switch code

[Eric Sosman]

parag_paul@xxxxxxxxxxx wrote:
>   void duff(register char *to, register char *from, register int
> count)
>   {
>       register int n=(count+7)/8;
>       switch(count%8){
>       case 0: do{ *to++ = *from++;
>       case 7:  *to++ = *from++;
>       case 6: *to++ = *from++;
>       case 5: *to++ = *from++;
>       case 4: *to++ = *from++;
>       case 3: *to++ = *from++;
>       case 2: *to++ = *from++;
>       case 1: *to++ = *from++;
>               }while( --n >0);
>       }
>   }

    Do you have a question?

    Incidentally, despite the suggestive name given to
the function this is not Duff's Device.  Also, there's a
better way to accomplish what this code does: call
memcpy (or perhaps memmove) instead.

--
Eric Sosman
esosman@xxxxxxxxxxxxxxxxxxxx