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SubjectRe: SysV IPC message queues
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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