Contents of the VMS sub-archive for UnZip 5.0 and later:

  Contents                   this file
  VMS.notes                  general VMS info about installing and using UnZip
  unzip.rnh                  UnZip manual page, RUNOFF format
  vms.c                      VMS file manipulation code
  make_gcc_unzip.com         command file to compile UnZip and ZipInfo w/ GNU C
  make_vaxc_unzip.com        command file to compile UnZip and ZipInfo w/ VAX C
  makefile                   MAKE/VMS makefile for UnZip and ZipInfo
  descrip.mms                MMS makefile for UnZip and ZipInfo
  vmsshare.opt               options file used in descrip.mms
  bilf/bilf.c                BILF source code
  bilf/bilf.exe              BILF executable (binary)
  bilf/make_bilf.com         command file to compile BILF with VAX C

BILF may be required for older zipfiles or for those created under other
operating systems.  Instructions for its use are in the source code.

The non-decryption version of UnZip compiles fine with VMS GCC, although
you may get a lot of warnings (especially for vms.c).  Ignore them; GCC
is hyper-picky.

MAKE/VMS v3.4 is Todd Aven's 1989 make utility (Software Sweatshop, NY); his
e-mail address is listed as todd@cincom.umd.edu.  The version used here has two
revisions by Ned Freed (1989, 1990) and one by Greg Roelofs (1992--options to
use either creation date or revision date for determining out-of-date-ness).
Check valeria.cs.ucla.edu in /pub/VMS or /infozip for vms_make.zip, or send 
e-mail to zip-bugs@cs.ucla.edu if it's not there.  The original is stored on 
vmsa.oac.uci.edu.