Question

I got a memcpy function that look strange on how it was used. I pasted it below. Can someone please help explain it. I do not know why the (void *). buffer is buffer in struct BLK. Thanks.

    memcpy(     
                (void *) (BLK->buffer + left),
                (void *) input,
                fill            
          );

Answer 1

There is no need for the cast, assuming input and BLK->buffer are already pointer types (which they really should be).

I can think of two reasons why they’re there:

• The author was paranoid.
• The author was making it clear that he/she understands that the specific pointer type is going into a “generic” function.