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mq_setattr(3)
NAME
  mq_setattr - Sets the mq_flags attributes associated with a message queue
  (P1003.1b)

LIBRARY
  Realtime Library (librt.so, librt.a)

SYNOPSIS
  #include <mqueue.h>

  int mq_setattr (
  mqd_t mqdes,
  const struct mq_attr *mqstat,
  struct mq_attr *omqstat);

PARAMETERS
  mqdes	      Describes the message queue for which attributes are to be set.

  *mqstat     Specifies a pointer to a mq_attr structure that specifies
	      attributes to be set for the specified message queue.

  *omqstat    Specifies a pointer to a mq_attr structure that stores the
	      previous message queue attributes and the current queue status.
	      These are the values that would be returned by a call to the
	      mq_getattr function at that point.

DESCRIPTION
  The mq_setattr function sets the mq_flags attributes associated with the
  message queue descriptor for the calling process.  Only the blocking
  attribute of the queue for the calling process can be modified through this
  call.	 Modifying the blocking attribute for a queue has no effect on
  currently blocked processes.	Other members of the mq_attr structure are
  ignored by the mq_setattr function.

RETURN VALUES
  On successful completion, the function returns the value 0 (zero) and the
  message queue attributes will have been changed as specified.

  Otherwise, the value -1 is returned, errno is set to indicate the error,
  and the message queue attributes remain unchanged.

ERRORS
  The mq_setattr function fails under the following conditions:

  [EBADF]	 The mqdes argument is not a valid message queue descriptor.

  [EINVAL]	 The mqstat argument is a NULL pointer.

RELATED INFORMATION
  Functions: mq_open(3), mq_send(3)

  Guide to Realtime Programming

Index for Section 3

Alphabetical listing for M

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