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   alt.os.development      Operating system development chatter      4,255 messages   

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   Message 3,361 of 4,255   
   mutazilah@gmail.com to Joe Monk   
   Re: segmentation   
   23 Oct 22 16:20:04   
   
   From: muta...@gmail.com   
      
   On Monday, October 24, 2022 at 7:01:58 AM UTC+8, Joe Monk wrote:   
   > > The segments get loaded with values that were set by the OS   
   > > at load time, typically. The program wouldn't be relocatable   
   > > otherwise.   
   > >   
   > Thanks for proving my point. :)   
      
   No, I did no such thing.   
      
   > If the OS loads a program at 2B0:13 and 2C0:3, the OS will overwrite one   
   program with another.   
      
   But that's the whole point of the OS. It is required to manage   
   memory so that that doesn't happen.   
      
   Since the memory to be managed is more than 64k, the OS   
   needs to effectively using huge pointers, and as such the   
   huge memory model OS needs to generate code that is   
   aware of the segment shift value.   
      
   It may even be necessary to have a different version of MSDOS   
   (executables, not source code, at least if it is written in C) for   
   every shift value, plus another version for the 80286 and another   
   version for the 80386.   
      
   But that doesn't affect the applications which aren't affected   
   one iota.   
      
   BFN. Paul.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)   

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