Send message descriptor format

Format of snd_msg parameter:

*snd msg/4 -- message descriptor address

$=0$ :

short message (no memory data)

$\neq 0$ :

address of message descriptor
m -- mapping bit

$=0$ :

by-value send operation
message string contains only by-value data

$\neq 0$ :

by-reference (mapping) send operation
beginning of message string contains fpage descriptors
(potentially followed by more by-value data)
d -- deceiving bit: lie about sender
turned on automatically by using deceiving send binding.

Gernot Heiser 2002-08-07