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35 .Nd "get message queue attributes (REALTIME)"
41 .Fn mq_getattr "mqd_t mqdes" "struct mq_attr *mqstat"
45 system call obtains status information and attributes of the message queue and
46 the open message queue description associated with the message queue
51 argument specifies a message queue descriptor.
53 The results are returned in the
55 structure referenced by the
59 Upon return, the following members will have the values associated with the
60 open message queue description as set when the message queue was opened and
61 as modified by subsequent
66 The following attributes of the message queue will be returned as set at
67 message queue creation:
68 .Va mq_maxmsg , mq_msgsize .
70 Upon return, the following members within the
72 structure referenced by the
74 argument will be set to the current state
76 .Bl -tag -width ".Va mq_flags"
78 The number of messages currently on the queue.
91 argument is not a valid message queue descriptor.
101 system call conforms to
106 message queues first appeared in