From: ldo@nz.invalid   
      
   On Thu, 3 Jul 2025 10:56:26 -0400, Arne Vajhøj wrote:   
      
   > 5) The idea of emulating one OS on another OS is questionable   
   >     in itself. It is not that difficult to achieve 90-95%   
   >     compatibility. But 100% compatibility is very hard. Because   
   >     the core OS design tend to spill over into   
   >     userland semantics. It is always tricky to emulate *nix   
   >     on VMS and it would be be tricky to emulate VMS on *nix.   
      
   It was always tricky to emulate *nix on proprietary OSes. But emulating   
   proprietary OSes on Linux does actually work a lot better. Look at WINE,   
   which has progressed to the point where it can be the basis of a   
   successful shipping product (the Steam Deck) that lets users run Windows   
   games without Windows. That works so well, it puts true Windows-based   
   handheld competitors in the shade.   
      
   That has never been done before. And it’s got to be a more difficult job   
   than emulating VMS, with its much simpler APIs.   
      
   > Getting DCL, image activation, process permanent files,   
   > subprocesses, logicals and symbols working 100% compatible on a   
   > Linux kernel would not be easy. A lot hang on the 4 mode design and   
   > DCL being in S.   
      
   We don’t need to emulate the internals of DCL. We just need to be able to   
   run users’ command procedures.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)