From: cross@spitfire.i.gajendra.net   
      
   In article <873474p1an.fsf@atr2.ath.cx>,   
   jayjwa   wrote:   
   >Arne Vajhøj  writes:   
   >[snip]   
   >> My understanding about VAXELN (based on what I have been told - no   
   >> personal experience) is that you link the OS into the application   
   >> and deploy the application (with embedded OS) directly on   
   >> the VAX.   
   >   
   >It's an SDK but no one calls it that. It would be much easier to   
   >understand if they did. One creates an application in C or Pascal. Then   
   >you compile/link it with ELN libraries. Maybe it supports other   
   >languages but the docs mention C and Pascal.   
      
   According to the VAXELN Technical Summary, it also contains a   
   runtime component that includes the kernel, which manages tasks   
   and provides synchronization/concurrency primitives, and little   
   else.  Even drivers are userspace processes; it's very   
   microkernelesque.   
   https://archive.org/details/h42_DEC_VAXELN_Technical_Summary/   
      
   I suspect something that throws people unfamiliar with embedded   
   and/or real-time systems for a loop is that the system is   
   statically configured at build time.  That is, one builds a   
   system configured with exactly those services, drivers, programs   
   etc, that are actually going to run on the target system.  And   
   yet there still is a real kernel there, unlike a pure "bare   
   metal" program written by an end user that has, essentially, no   
   runtime at all other than one the programmer provides.   
      
   	- Dan C.   
      
   --- SoupGate-Win32 v1.05   
    * Origin: you cannot sedate... all the things you hate (1:229/2)