title: Reading part of a file into a Stream in Powershell
body: <p>I have some files which are 'offsetted' Zip files in that they have 4 extra bytes at the begining which must be ignored when extracting them.</p>
  
  <p>I've been using ReadAllBytes/WriteAllBytes (with an offset of 4) - that works but obviously I have to write read/write/read the file which is slow.</p>
  
  <p>I'd prefer to use System.IO.Compression.ZipArchive to read from a Stream loaded from the file (sans the first 4 bytes) - but I cannot figure-out the steps required to do that?</p>
  
  <p>I tried 'Seek' but ZipArchive ignores position 
  I cannot seem to get Byte Arrays to pass into System.IO.Compression at all...</p>
  
  <p>Ideas?</p>