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A3 - seq

On Tue, 10 Mar 1998, Fei Wang wrote:

> in struct ipc_perm, there is a field called "ushort seq", could you
> explain what seq = slot usage sequence number is for? We found seq in a
> few function, e.g semget is supposed to return the id of the semaphore set
> found with the given key, however, it returns 
> (unsigned int) sma->sem_perm.seq * SEMMNI + id. 

That's because seq is, by definition, the sequence number of the slot
taken by an ipc permission struct. Have a look at sys_semctl first,
to see how it is manupulated.

Ciao
Franco