MQ_GETATTR(3C)MQ_GETATTR(3C)NAMEmq_getattr - get message queue attributes
SYNOPSIS
#include <mqueue.h>
int mq_getattr(mqd_t mqdes, struct mq_attr *mqstat);
DESCRIPTION
The mqdes argument specifies a message queue descriptor. The
mq_getattr() function is used to get status information and attributes
of the message queue and the open message queue description associated
with the message queue descriptor. The results are returned in the
mq_attr structure referenced by the mqstat argument.
Upon return, the following members will have the values associated with
the open message queue description as set when the message queue was
opened and as modified by subsequent mq_setattr(3C) calls:
mq_flags
message queue flags
The following attributes of the message queue are returned as set at
message queue creation:
mq_maxmsg
maximum number of messages
mq_msgsize
maximum message size
mq_curmsgs
number of messages currently on the queue.
RETURN VALUES
Upon successful completion, the mq_getattr() function returns 0. Oth‐
erwise, the function returns −1 and sets errno to indicate the error.
ERRORS
The mq_getattr() function will fail if:
EBADF
The mqdes argument is not a valid message queue descriptor.
ENOSYS
The mq_getattr() function is not supported by the system.
ATTRIBUTES
See attributes(5) for descriptions of the following attributes:
┌────────────────────┬───────────────────┐
│ ATTRIBUTE TYPE │ ATTRIBUTE VALUE │
├────────────────────┼───────────────────┤
│Interface Stability │ Committed │
├────────────────────┼───────────────────┤
│MT-Level │ MT-Safe │
├────────────────────┼───────────────────┤
│Standard │ See standards(5). │
└────────────────────┴───────────────────┘
SEE ALSOmsgctl(2), msgget(2), msgrcv(2), msgsnd(2), mqueue.h(3HEAD),
mq_open(3C), mq_send(3C), mq_setattr(3C), attributes(5), standards(5)NOTES
Solaris 2.6 was the first release to support the Asynchronous Input and
Output option. Prior to this release, this function always returned −1
and set errno to ENOSYS.
Feb 5, 2008 MQ_GETATTR(3C)