Re: SysV IPC message queues

[David Newall]

Kyle,

Processes do not open nor close message queues, rather they place 
messages on and fetch them from queues.  Let me say this again: you do 
not open a queue like you must for a file, but go directly to the 
equivalent of read and write.  There is no refcount to indicate how many 
processes are "using" a queue, although there may be one indicating how 
many are actively waiting to receive a message.  Removing a queue when 
that count reaches zero would be quite wrong because a process stops 
waiting as soon as it receives a message; so the count would be zero 
more often than not.

Do not allow IPC_PRIVATE to lead you into false understanding of what a 
message queue is.  IPC_PRIVATE does not cause creation of a private 
queue, as indicated in msgget(2): "The name choice IPC_PRIVATE was 
perhaps unfortunate, IPC_NEW would more clearly show  its  function."  
Queues are not accessed by key but by id.  You do not need to know the 
key for a queue to access it, neither do you need to use msgget(2) to 
find a queue's id.

So, no, sorry, but your idea must be rejected.

David
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