mq_setattr(3)						     Library Functions Manual						     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 block-
       ing  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 delim off

																     mq_setattr(3)