CompuServe Thread

#Sherlock: Give us a clue

6 messages in this thread
#47698From: Ron WodaskiMay 4, 1993 11:47 PM
General Protection Faults occur in environments that switch the CPU into protected mode. Windows does this, as do many DOS-extender technologies such as Phar Lap. In protected mode, a program can only use memory that it owns. That's where the "protected" comes from — the memory pool is protected from ill-behaving programs that try to get at memory addresses that haven't signed up for. A GPF occurs when a request is made for memory a program doesn't own. Ron
#47706From: Lynne EllinwoodMay 5, 1993 2:03 AM
Ron, Now that's probably the clearest explanation I've read of "protected" mode. I knew that GPFs were related to "off-limits" memory, but had no real idea of how they related to Windows. Obviously, I need to do more reading, but it helps a lot to have the field narrowed. Thanks a lot. Lynne
#47715From: Jack L. ChalkerMay 5, 1993 4:33 AM
Interesting. I knew of a lot of error messages but never saw a GPF message outside of Windows….
#47732From: Ron WodaskiMay 5, 1993 9:52 AM
When I was working with OS/2 before there was a thing called Program manager, we'd get them all the time at the company I worked for. I also did a lot of debugging work on a major software package we all know and hate using a DOS extender, and therefor also using protected mode. GPFs are a great way to uncover bugs that otherwise won't show up until the user gets the product. <g> I believe there is a product out that deliberately runs your software under protected mode so it can find memory walk-overs. Ron
#47797From: Jack L. ChalkerMay 6, 1993 4:27 AM
Well, the original OS/2 code was MicroSoft's, so you'd expect much the same error codes there. I have a certain grudging admiration for MicroSoft. Remember how they promised no more UAEs if you went from WIN30 to WIN31? And they kept their word. They renamed them….
#47816From: Ron WodaskiMay 6, 1993 9:15 AM
Yeah, I love it. I actually do have a gruding admiration for Microsoft. They may be a lot of things, but some good software does come out of there. Now if it only started there… <vicious evil grin> Ron