title: memcpy equivalent for skipping x bytes while copying (not just initial x bytes)?
body: <p>I'm looking for an existing function similar to memcpy that can be told to copy <em>x</em> bytes and then skip <em>y</em> bytes, repeating until a specified amount has been copied.</p>
  
  <p>Imagine a buffer with data: <code>AABAAB</code> (I've used characters, but the data I'm manipulating is not string data).</p>
  
  <p>When applied to this buffer and told to copy 2 bytes and skip 1 byte, the destination buffer would contain: <code>AAAA</code>.</p>
  
  <p>I haven't found anything looking through STL and Boost, but am hoping there's something in either that I've missed.</p>
  
  <p>Or perhaps there's a clever (and not nasty) way of using more common functions to achieve the same thing.</p>