On 2004-03-01, Bart Oldeman wrote: > I don't think dx=ffff is a problem for floppies / <32MB for any DOS >= > 3.31. But I'm not a 100% sure; I know for sure that people have used > sys successfully from DOS 6.22
Yep. For maximum compatibility with 3rd-party DOSes such as DR DOS 3.xx you should always use the 'new' form of INT 25h/INT 26h when running on DOS 3.31+. If you would use the old call, it will crash under older issues of DR DOS unless you would special case them. On the other hand, always using the new form on any DOS 3.31+ the least does not cause any problems under DR DOS, PC DOS or MS-DOS, even if the disk is smaller than 32 Mb. I'm not sure if the absread()/abswrite() TC RTL functions get this right, so I would better not trust on them because they might have been tested under then-current issues of MS-DOS/PC DOS only. And things have changed a bit with DOS 7.10+, anyway. On a different note: Somewhen some weeks ago, Eric mentioned that he wouldn't trust RBIL in regard to the special case of error code 0408h mentioned there under INT 25h, and that in one of his tools he planned to retry with bit7 of the drive number set on 0207h or something like this (sorry, if I mix this up now, I cannot find the original post right now, it's just that I still remember the issue a little because I was working on absolute disk read/write stuff myself around this time, and now that I read INT 25h it springs back into my mind). I had wanted to drop a note on this in this forum, but didn't found the time. I don't know what further happened in regard to this issue, but if it helps to clarify the issue a little, the value given in RBIL61 is in fact correct as it is. Purpose unknown, though. Hope it helps, Matthias -- <mailto:[EMAIL PROTECTED]>; <mailto:[EMAIL PROTECTED]> http://www.uni-bonn.de/~uzs180/mpdokeng.html; http://mpaul.drdos.org "Programs are poems for computers." ------------------------------------------------------- This SF.Net email is sponsored by: IBM Linux Tutorials Free Linux tutorial presented by Daniel Robbins, President and CEO of GenToo technologies. Learn everything from fundamentals to system administration.http://ads.osdn.com/?ad_id=1470&alloc_id=3638&op=click _______________________________________________ Freedos-kernel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/freedos-kernel
