Here you can fetch the files that were distributed on the floppy bundled
       with the 1994 "DOS Internals" book by Geoff Chappell.
       
   BIN DOS_Internals.zip
       
       Between 1997-2009, the author provided an errata to his book through his
       website (originally at http://www.geoffchappell.com/notes/dos/internals/).
       Below I list the two errata notes, as fetched the 23rd of January, 2017:
       
   DIR Updated CRTDRVR library
   DIR Corrected XMSWATCH