From: "John M. Aldrich" Newsgroups: comp.os.msdos.djgpp Subject: Re: Extender compatibility and bootstrapping DJGPP Date: Sat, 30 Nov 1996 00:08:54 -0800 Organization: Three pounds of chaos and a pinch of salt Lines: 85 Message-ID: <329FEB96.3FC3@cs.com> References: <57nt0i$k92 AT hacgate2 DOT hac DOT com> Reply-To: fighteer AT cs DOT com NNTP-Posting-Host: ppp102.cs.com Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit To: Stephen Pushak DJ-Gateway: from newsgroup comp.os.msdos.djgpp Stephen Pushak wrote: > > Ok, a few dumb questions from a newbie. My internet > access is limited so I don't have the full FAQ yet. (take > pity on me and mail it to spush AT hcsd DOT hac DOT com if you have it) The FAQ is _far_ too big to post on the newsgroup or send via email, but you can read it online at http://www.delorie.com/djgpp. Once your net access is working, you can get it from ftp://ftp.simtel.net/pub/simtelnet/gnu/djgpp/v2/faq202b.zip. > What extenders is DJGPP compatible with? Does it come with its own? DJGPP does not use a DOS extender; it uses a full-fledged DPMI host. Programs written under DJGPP v2 can run in any enviroment where DPMI exists, or they can use the freeware "cwsdpmi" program which comes with the distribution. The differences between the various hosts are subtle, but can sometimes be problematic if you depend too heavily on certain types of operations. In general, CWSDPMI gives you the best overall performance both speed-, reliability-, and space-wise. DJGPP is not compatible with any kind of DOS extenders, specifically DOS4G. There isn't really anything that can be done about this, but fortunately it isn't possible to make DOS4G a resident host. :) > What are the license restrictions if so? (typical GNU?) DJGPP itself is completely freeware, and does not fall directly under the GNU GPL. However, it does have some basic licensing restrictions, and many of the sources and libraries DO fall under the GPL. The various documents, particularly the FAQ, cover this subject in much greater detail. > Is it DPMI version 1 or 2? compatible under VCMI? Third party > or in GNU source form? The vast majority of DPMI hosts only support DPMI 0.9 functions. Some, like CWSDPMI, implement some, but not all of the 1.0 functions, while I think 386MAX is the only one that supports all of the 1.0 spec. DPMI is capable of running under any kind of memory management, except that only one DPMI host can be running at any given time (thus, if you run programs under Windoze, you're stuck with the Windoze DPMI). Note: the above applies only to DJGPP v2.x. DJGPP v1.x was able to run in a non-DPMI environment using a quasi-extender (go32), but had so many flaws because of it that v2.x was moved to DPMI-only. > If I get the CD-ROM, does it include binaries or do I need a > 32 bit compiler to bootstrap the source into binaries? I don't know for sure, but I don't think the CD-ROM includes the most current version of DJGPP. In any case, it does have the full binaries. > Does one use the DJGPP cc compiler typically to compile the GNU sources? > or are other C compilers acceptable? Intel offered a 32 bit > DPMI compiler for a while there at low cost. It's extender wasn't terribly > good as DPMI extenders go and lacked the compatibility we needed > at that time but it might be a good choice if one had to bootstrap > from source. The GNU sources _can_ be compiled out of the box with DJGPP, but in general most Unixy programs require some degree of modification to work _well_ under MS-DOS. DJGPP's distribution includes the source code to all the GNU packages as separate zipfiles, and this source has already been completely ported to DOS/DJGPP. OTOH, since GNU development is an ongoing process, I think many of the MS-DOSish changes are in the process of being added to the original sources themselves, but Eli Zaretskii knows more about this than I. As far as other compilers go, AFAIK the GNU sources require a fully POSIX-compliant compiler to build properly on MS-DOS, which Borland, et. al. are not. The Cygnus-Win32 project supposedly provides a GNU-based compiler that is native to Win95, but it is not yet close to completion. I don't know anything about the Intel compiler. Nevertheless, since DJGPP comes with pre-compiled binaries, you should be set to go just by downloading the distribution. DJGPP was designed specifically so as not to require any form of bootstrapping. ;) -- --------------------------------------------------------------------- | John M. Aldrich, aka Fighteer I | fighteer AT cs DOT com | | Proud owner of what might one | http://www.cs.com/fighteer | | day be a spectacular MUD... | Plan: To make Bill Gates suffer | ---------------------------------------------------------------------