System V shared memory and sbrk(2)

[Danny]

Greetin's

    In Marc Rochkind's book, "Advanced Unix Programming," page 194,
he states that there may be conflicts between shmat(2) and sbrk(2)
(or brk(2)).  That once a shared-memory segment is attached, one
cannot call brk or sbrk again.

    My question is: why is this?  Why cannot the kernel respect previous
segments and honor new ones?  Is this a hardware limitation?  Security?
Kernel programmer laziness?  Recent solar flare activity?  Fixed in
System V Release 10 to the power 9?

                                        Thanks Loads,

                                        Danny
-- 
				Daniel S. Cox
				(seismo!gatech!itm!danny)