🚀 go-pugleaf

In article <MIB.91Jun25133212@geech.gnu.ai.mit.edu> mib@geech.gnu.ai.mit.edu (Michael I Bushnell) writes:

   In article <BUZ.91Jun24165007@buz.eng.ready.com> buz@@eng.ready.com (Greg Buzzard) writes:

      What is the reason for the mach_port_allcate_name function being in the
      kernel interface? ...

      Similarly, it seems that it would have been nice if
      mach_port_insert_right was restricted to only insert rights using a
      "name" that had been previously extracted.

   Here are two examples of this utility:

   A server can arrange, with mach_port_allocate_name, to have port
   rights correspond directly to addresses of relevant data structures in
   its address space, saving a table lookup.

Yuck! :-) I don't see how you can resolve the possibility of multiple
servers that might want to do this with the same virtual addresses.
If you pass the port numbers as ints (so the kernel wont remap them
for the receiver) then you lose the ability to lookup the object on
the receiving side, right?  Is this trick good for only a single
server?  Feel free to point me at some sample code to look at for further
"enlightenment", if you want...

   The GNU emulator uses mach_port_insert_right to copy some port rights
   to a child when a fork happens.  It wants to insert them into the
   child under the same name they had in the parent.  Your condition
   would prevent them from being inserted at all.

Ah, yes... good point.

So I guess sparse port spaces are unavoidable.  

Thanks folks,
--
Greg Buzzard	 			internet:  buz@eng.ready.com
Ready Systems
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