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   comp.lang.c      Meh, in C you gotta define EVERYTHING      243,242 messages   

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   Message 241,805 of 243,242   
   Lawrence =?iso-8859-13?q?D=FFOlivei to Peter Flass   
   Re: 16:32 far pointers in OpenWatcom C/C   
   04 Nov 25 22:17:44   
   
   XPost: alt.folklore.computers, openwatcom.users.c_cpp   
   From: ldo@nz.invalid   
      
   On Tue, 4 Nov 2025 09:39:41 -0700, Peter Flass wrote:   
      
   > I was thinking, are there any segmented architectures today?   
      
   Two different meanings of segmentation. It is possible to use segmentation   
   in a flat address space, as a memory-management technique. Think paging,   
   but with variable-length pages. (E.g. Burroughs machines did this. Also   
   think of how program code on the old 680x0-based Macintosh machines could   
   be divided up into individually-swappable “CODE” segments.)   
      
   The trouble was, such a scheme was prone to fragmentation, where the total   
   free memory might be larger than the segment you want to load, but it’s   
   broken up into discontiguous pieces that are too small to use. This is why   
   paging was preferred instead.   
      
   But now, with 64-bit architectures commonplace, you have multi-level page   
   tables. Think of these as a form of segmentation, where each segment is   
   made up of whole pages.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)   

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