Hi, after PTS-DOS, the DR-DOS enhancement people have added an option to put more data structures of DOS into UMB (I guess this time we are talking about LoL / SDA). That way they get 626k of 640k low DOS RAM free after loading HIMEM/EMM386.
If you want to keep up with the game, we could add such an option to FreeDOS, too. However, we already do have 622k low DOS RAM free in a quite straightforward configuration (in DOSEMU, where HIMEM / EMM386 take almost no memory, even 627k), and I never met any program which really needed more than 590k, so this is only about bragging. Relocating LoL/SDA into UMB might be a bit tricky, and it will not work if programs outside the kernel start using it before it gets moved. However, HIMEM / EMM386 are usually loaded first, so... More interesting and useful would definitely be something like my suggested "checksum some/all SFT entry fields and force an update of the corresponding f_node if a SFT entry is found to be changed from outside. I believe this would be necessary to allow DOS boxes to work inside Win 3.x standard mode (DSWAP/WSWAP)." Eric PS: Other interesting details: Our STACKS data structure is very different from / simpler than classic DOS 3.x STACKS, and we support neither int 2f.13 (rehook int 13) nor offer an int 13 wrapper which avoids DMA problems (we just avoid them in the kernel BEFORE calling the disk device driver, so programs which call int 13 directly have to check for DMA boundaries themselves) nor do we have the "original int vectors 10/13/15/19/1b" data at 70:100 or the DDPT at 0:522 (we have it at 70:0). Hard to tell which compatibility problems those details could cause. Bonus question: Does MS DOS actually call int 25/26 itself or does it - like FreeDOS - only offer int 25/26 for disk tools, but calls the device drivers directly for everything else? ------------------------------------------------------- This SF.Net email is sponsored by: YOU BE THE JUDGE. Be one of 170 Project Admins to receive an Apple iPod Mini FREE for your judgement on who ports your project to Linux PPC the best. Sponsored by IBM. Deadline: Sept. 13. Go here: http://sf.net/ppc_contest.php _______________________________________________ Freedos-kernel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/freedos-kernel
