send/receive confusion

[gernot at cse.unsw.edu.au]

Edmundo,

I think I now understand the source of your confusion. In the Intel
version of the L4 manual (at least in my copy of Sep 96), on p25 where
the "rcv descriptor" is explained, the option "mem" has the top 30 bits
of the descriptor word as "*snd msg/4". That should, of course, read
"*rcv msg/4".


Also, further to what I wrote in my previous mail:


GH> - one or more page mappings or grants, provided that
GH>    - the "m" bit is set in the send descriptor, and
GH>    - the beginning of the sender's direct string (starting with the
GH>      register part) contains at least one valid "send fpage", and
GH>    - the receive descriptor either has the form of a valid "receive
GH>      fpage", or points to a "message" struct containing a valid "receive
GH>      fpage", and
GH>    - there is no error

The second last bullet should read:

   - the receive descriptor either has the form of a valid "receive
     fpage" and the "m" bit is set, or points to a "message" struct
     containing a valid "receive fpage", and

Gernot
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