[comp.os.xinu] Stack allocation in PCXINU !!!

852026d@aucs.uucp (DAWD) (03/07/90)

    It is mentioned in Comer/Fossum's book ,XINU P.C edition, that
PCXINU allocates a stack area for each process, in a way that if more 
than one process starts, their stacks are allocated CONTIGUOUSLY upward.

I found out that PCXINU does not allocate processes' stacks CONTIGUOUSLY,
because when PCXINU creates a process it uses function getmem() to allocate 
it's stack , and function getmem() simply returns the first free block of
memory from the free list. The following code will show it clearly  : -


      ...
      resume(creat(process#2,......));
      userblock = getmem(100);
      resume(creat(process#2,......));
      ....
   

Please post any comments .

  Thank You