Contents of the "proginfo" subdirectory for UnZip 5.42 and later:

  Contents      this file
  CONTRIBS      list of contributors to UnZip
  ZipPorts      Info-ZIP rules and guidelines on contributions to the cause
  3rdparty.bug  known bugs in PK[UN]ZIP, WinZip, etc.
  defer.in      info about the NEXTBYTE macro and defer/undefer_input functions
  extrafld.txt  info about all known "extra field" types
  fileinfo.cms  info about the VM/CMS file system, including record formats
  nt.sd         info about support for Windows NT's Security Descriptors (ACLs)
  perform.dos   relative performance of Zip and UnZip with various DOS compilers
  timezone.txt  explanation of the TZ environment variable for timezones
  ziplimit.txt  limits of the Zip archive format and InfoZip's implementation
