Tandem Port History===================Hi, I'm Dave Smith and I work at BP Oil UK, looking after their European cardprocessing system since 1992.  We need to send lots of files via FTP to otherBP machines (Novell, NT, Sun...). Sending large files was frowned upon, so thesearch for a zip product was on.We tried the GZIP product from Twinsoft Netherlands but it was complicated touse and it was not widely known by other arts of BP.What we really wanted was a PKZIP compatible product, as this is a widely knownproduct.  By chance when surfing the web I discovered the Info-ZIP web site.This claimed PKZIP 2.04g compatibility and had a number of ports, was free, andeven had source code, but unfortunately no Tandem version :-(Thus in the autumn 1996 I bit the bullet and took on the job of porting thecode to Tandem NSK (Guardian).  This meant dusting off my circa 1985 'C'programming skills and firing up the Tandem 'C' compiler - not known for itsease of use, especially debugging 8-;  This was all on D30 by the way.To start this off I had to choose an existing port to base te Tandem one on.Nearest (?) was the VM-CMS/MVS port by George Petrov.  The main similaritybeing that these machines are record based, and have a similarish filing systemto Guardian.First to be tackled was ZIP.  By the end of 1996 I had a version which compiledand ran (giving the program banner) - which seemed like a major acheivement atthe time.In December 1996 I forwarded a version of ZIP to Info-ZIP which worked only on Edit files, and had no concept of directories.  Became ZIP 2.1By March 1997 I had improved ZIP so that it could cope with Unstructured filesas well (Became ZIP 2.2).  I also had ported a version of UNZIP which couldcreate Unstructured files (not Edit) - UNZIP 5.20At the start of September 1997 I sent UNZIP with Edit file support to Info-ZIP(incorporated into 5.32)In March 1998 I submitted file I/O improvements (SBB) for ZIP (2.3a)In August 1998 I added Tandem DEFINE processing for ZIP (2.3e).  This was afeature required by BP to allow them to store files with a different internalname than the physical file being zipped (without renaming it).Also added storing of proper UTC timestamps which allow for DST & timezone.Also in August I added the same file I/O improvements for UNZIP (5.33f)I then added the ability to update the unzipped files last modified and lastopen timestamps - this required help from TNSC to allow me access to thepriviliged procedure call.  Also can give the files back to the original userby use of the '-X' flag.At the end of 1998 I was given the go ahead to add the zipping of Enscribefiles.  This first version stores all Enscribe file attributes EXCEPT SQL, altkey and partition information.ZIP now uses its own Guardian I/O (rather than the 'C'library) for the readingof files to be zipped.Unstructured files use Large Transfer mode and READ (56K or 30K reads)Edit files use IOEdit routinesEnscribe files use READ and SBB and add LF to the end of each record.UNZIP has the ability to update the filecode of files restored to ther originalvalue (Unstructured only)To Do ZIP===========1. Change I/O to use NSK/Large Transfer mode in fwrite of ZIP file itself- this   will dramaticaly speed up updating an existing zipfile. When updating an   existing zipfile it copies it to a temporary file currently using only SBB.2. Add raw binary mode to allow storing of raw data in zip file - e.g. only to   be unzipped on Tandem !  This is simplest/fastest way to provide full   Enscribe support for Tandem platform - with no cross-platform support.3. Add SQL support !!To Do UNZIP===========1. Re-write the I/O routines to use NSK to recreate the original Enscribe file   structure.2. Use NSK Large Transfer mode I/O for reading/writing of ZIP file3. Add raw binary mode to allow restoration of Tandem file from previous raw   data ZIP (see above)4. Add SQL support !!Current Versions on Website===========================ZIP 2.3UNZIP 5.5As of February 17th 2002