Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!samsung!think.com!snorkelwacker.mit.edu!bloom-picayune.mit.edu!athena.mit.edu!pshuang From: pshuang@athena.mit.edu (Ping-Shun Huang) Newsgroups: comp.sys.ibm.pc.misc Subject: Re: Looking for MS-DOS 5.0 Compatibility Tricks... Message-ID: Date: 17 Jun 91 23:41:05 GMT References: <1991Jun16.043650.7990@vpnet.chi.il.us> Sender: news@athena.mit.edu (News system) Organization: Massachusetts Institute of Technology Lines: 42 In-Reply-To: mox@vpnet.chi.il.us's message of 16 Jun 91 04:36:50 GMT In article <1991Jun16.043650.7990@vpnet.chi.il.us> mox@vpnet.chi.il.us (William Moxley) writes: > I have several programs that will not work with the new version of > MS-DOS. [....] specifically having trouble with are Norton's Disk Cache > and DoubleDos V5.0 although their are several others... When Microsoft put in the setver command, they probably intended for it to circumvent two situations: (a) when programs are far more sensitive to DOS versions than they really need to be, DOS external utilities like XCOPY will simply *NOT* run under any other version of DOS, even though the version number should not matter to XCOPY unless it is less than 2.x in which case subdirectories don't exist {grin}. (b) more importantly, programs which need certain DOS services or functionality which are only available after a certain version of DOS; subdirectories with 2.x, for example, but some others as well which are not visible to the end user but only to programmers. If programmers for an application were sloppy and onl*ONLY* checked to see if the current DOS version is 3.x or 4.x and if not, *AUTOMATICALLY* assumed that they were running on 2.x or {heaven forbid} 1.x and quit, this would make a lot of users of such an application unhappy. Hence SETVER to make your DOS look like some other version of DOS. In your case, the programs which you cite are very low-level programs, one being a disk cache and the other being a multitasker. While I don't know if they fall into category B or not, these are exactly the kind of programs which really *DO* need to know what version of DOS they're actually running under, because they often peek under the hood. Microsoft did their best to make DOS 5.0 compatible with widely available programs (including continuing to implement undocumented DOS functions which were commonly used), but even so, in the case of DOS 5.0, peeking under the hood in a non-standard fashion might leave you looking at nothing, since some of DOS now sits in high memory blocks and HMA. If you cannot get such low-level programs to run natively under 5.0, you can try blindly running them with SETVER, but I would recommend a quick call to the manufacturer support line to check compatibility. -- Singing off, UNIX:/etc/ping instantiated (Ping Huang)