Message-ID: <01FD6EC775C6D4119CDF0090273F74A4021F0B@emwatent02.meters.com.au> From: "Da Silva, Joe" To: "'opendos AT delorie DOT com'" Subject: RE: TGZ compression (was Greed, nee DPMS info) Date: Tue, 30 Jan 2001 13:09:59 +1100 MIME-Version: 1.0 X-Mailer: Internet Mail Service (5.5.2448.0) Content-Type: text/plain Reply-To: opendos AT delorie DOT com Yep, TGZ compression is very good - "all round" it outperforms anything else out there (AFAIK). The only problem I have with it is that GZIP/GUNZIP is the most user-vicious software I have ever tried to use!!! And the documentation is not much help. If you know how to use it *safely* under various DOS environments (with and without LFN), please tell us the secret! After my last attempt with GZIP, I gave up in disgust and used WinZip to extract what I wanted (yep, that's the Windoze package you are probably thinking of ...). As for UNTGZ, this is a MUCH, MUCH more user-friendly piece of software. Unfortunately, it doesn't always work. IIRC, the documentation mentions this WRT the infamous LZW compression, however I think it also baulks at very large files (?). Speaking of LZW, this is used, not just in many GIF files, but also some ZIP files, some PDF files, Unix 'compress' files (IIRC), some other graphics formats, etc. etc. etc. It is very pervasive, as it was the first "good" compression algorithm developed. Anyway ... having a look at patents recently, it appears that the LZW patent is due to expire in about 2.5 years. So eventually, all those programs where the LZW algorithm was removed thanks to Unisys (eg. Ghostscript, InfoZIP, etc.), can be made "whole" again. In the meantime just boycott all Unisys products! Joe. > -----Original Message----- > From: Patrick Moran [SMTP:pmoran22 AT yahoo DOT com] > Sent: Tuesday, 30 January 2001 11:06 > To: opendos AT delorie DOT com > Subject: Re: Greed (was DPMS info) > > I have a much better idea! Why doesn't everyone just use .tgz files!? > > That is use TAR through GZIP. You can use TAR and GZIP on every > operating system I have used. it with Unix, Linux, DOS, WINDOZE (3.x,) > OS/2. > > You can also use TAR and GZIP backups to tape drives, zip drives, hard > drives, LS-120, MO drives, or just about any other type of drive. It > will work with SCSI, QIC-20/30/60/120/150/250/525/etc. It will even work > with QIC-80. > > This way there would be a universal standard using FREE GNU/GPL > software. GZIP compression is better than PKZIP and probably equal to or > better than RAR. I would have to compress some large files and see if > GZIP is as good as the latest RAR. RAR may get better results from > multimedia files, but I get very little compression with those using RAR > anyway. > > I seem to remember that you can also unzip .ZIP files with GZIP. I > believe that is what I did with .ZIP files under Linux. However, PKZIP > cannot unzip GZIP files (at least the DOS version cannot.)The people > making packages and such for Linux got mad at RAR authors and have > pretty much given up on RAR. I can UNRAR files in Linux though. > > I think if people would use TAR and GZIP for DOS files and maybe other > files (most WINDOZE users are so dumb they > cannot do anything but point and click! Give them a program with some > real capabilities and the would be immediately lost!) All that would be > needed is to start using it for DOS files and who knows maybe someone > will write a frontend for it for WINDOZE and maybe even one for DOS so > you don't have to remember all those modifiers. (especially for tape > drives.) > ----- snip ----- > BTW one or both RAR and PKZIP WINDOZE versions will decompress .tgz > files. I don't recall which will do this. There is also a program for > DOS call UNTGZ. This is very easy and simple to use for files. (not > tapes and other media.) > > Pat > ----- snip -----