NAME    [Toc]    [Back]

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

SYNOPSIS    [Toc]    [Back]

       #include <mqueue.h>

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

LIBRARY    [Toc]    [Back]

       Realtime Library (librt.so, librt.a)

PARAMETERS    [Toc]    [Back]

       Describes the message queue for which attributes are to be
       set.  Specifies a pointer  to  a  mq_attr  structure  that
       specifies  attributes  to be set for the specified message
       queue.  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    [Toc]    [Back]

       The mq_setattr function  sets  the  mq_options  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    [Toc]    [Back]

       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    [Toc]    [Back]

       The  mq_setattr  function fails under the following conditions:
 The mqdes argument is not  a  valid  message  queue
       descriptor.  The mqstat argument is a NULL pointer.

SEE ALSO    [Toc]    [Back]

       Functions: mq_open(3), mq_send(3)

       Guide to Realtime Programming



                                                    mq_setattr(3)