Hi Lucho, Tom, others, I think before we all start buying SoftICE (yes, it is a bit old but seems to be very useful), try something else: BOCHS. http://bochs.sourceforge.net/ or something... Bochs has a BUILTIN debugger. Like you start Bochs on a Windows or Linux shell window (DOS box, xterm, ...). Then a new window shows up (the "screen" of the simulated PC) and - if configured to do so - the debugger starts up in the shell window. You can do some debugging FIRST if you want, or just type "continue" (or similar, check the help function of the debugger) to let the virtual PC boot. You can debug virtually everything. For example you can even set a breakpoint at the moment where protected mode is entered without knowing at which address this will happen. And you can continue debugging inside protected mode. All nice features, but based on the SIMULATED processor inside Bochs which - bad feature - makes the simulation slow.
On the other hand you can "boot" several Bochs windows at the same time and "reboot" quickly. And you get crash dumps in the logfile. Now about licenses: There are some nice short licenses like X11/Expat/BSD'/Artistic'/ Perl. Check the list on the gnu.org pages for more details. And of course there is public domain. Public domain is fine for small programs (like my CPULEVEL one). However, it does not protect anything. Somebody could take the code, cut and paste it into some other product and start selling it as closed source. So for bigger projects I prefer more "forced open" licenses like GPL and LGPL/BSD. The point about LGPL / BSD is that you can use the code in closed source projects (I think Windows contains parts under BSD license) as long as you keep a way open for the user to get the source code of those parts at no excessive extra costs (e.g. MS has some code online for download). GPL is more restrictive: You have to make the WHOLE sources open source if you compile something with GPLed sources inside. As others already told this does not mean that the compiler itself or the runtime libraries of the compiler are forced to be open source. Even GPL allows you (of course) to put some closed source or even non-free binaries and some binaries made from GPLed code together on one disk, to create a Linux / FreeDOS / ... distro. As long as you do not compile open and closed together into one binary, GPL is happy, roughly speaking. For executable packers this means: You could call the unpacking stub part of what is added due to the compilation process. Or you could open the sources of the (usually very short) unpacking stub. In either case you do not need to open the sources of the executable packer itself. Yes, GPL is very long. But people know it and it seems to be carefully designed so that even lawyers can understand it. This does not stop you from using much simpler licenses if you prefer to do so. I personally would like to have a short license like: You can use this code for free but have to keep the original copyright notice ... if you combine it with other code to create a single binary, you have to open that other source code, too. You can of course put my program on a disk with other programs with other licenses. You shall not remove any copyright messages from my program. You may not use the program for military, "intelligence" or other potentially inhumane or violent purposes. You are encouraged to tell me both if the program works fine and if it does not (e.g. because it has a bug or you have enhancement suggestions). I do not promise anything about the program. It seems to work for me, but if your computer falls into pieces then you cannot blame me - although I would be happy about a bug report if it really is my program which caused that. GPL comes pretty close to that, but uses longish legalese language. And I miss a statement about "humane" use. I know that some people think that violence can help to prevent other violence. But in most wars, BOTH parties feel like having the more noble reasons, so... If you have questions about Bochs, please start another thread. Just wanted to point at an alternative to SoftICE. If Borland 386 optimization uses 386 registers, you better do "pushad" - but then, is it WORTH the hassles? Just use 286 optimization. More interesting topic might be the license issue, so THAT part of this thread is encouraged to grow a bit :-). Eric. ------------------------------------------------------- The SF.Net email is sponsored by EclipseCon 2004 Premiere Conference on Open Tools Development and Integration See the breadth of Eclipse activity. February 3-5 in Anaheim, CA. http://www.eclipsecon.org/osdn _______________________________________________ Freedos-kernel mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/freedos-kernel
