1MQ_SETATTR(P)              POSIX Programmer's Manual             MQ_SETATTR(P)
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NAME

6       mq_setattr - set message queue attributes (REALTIME)
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SYNOPSIS

9       #include <mqueue.h>
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11       int mq_setattr(mqd_t mqdes, const struct mq_attr *restrict mqstat,
12              struct mq_attr *restrict omqstat);
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DESCRIPTION

16       The mq_setattr() function shall set attributes associated with the open
17       message queue description referenced by the  message  queue  descriptor
18       specified by mqdes.
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20       The  message  queue  attributes  corresponding to the following members
21       defined in the mq_attr structure shall be set to the  specified  values
22       upon successful completion of mq_setattr():
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24       mq_flags
25              The  value  of  this member is the bitwise-logical OR of zero or
26              more of O_NONBLOCK and any implementation-defined flags.
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29       The values of the mq_maxmsg, mq_msgsize, and mq_curmsgs members of  the
30       mq_attr structure shall be ignored by mq_setattr().
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32       If  omqstat  is non-NULL, the mq_setattr() function shall store, in the
33       location referenced by omqstat, the previous message  queue  attributes
34       and  the  current queue status. These values shall be the same as would
35       be returned by a call to mq_getattr() at that point.
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RETURN VALUE

38       Upon successful completion, the function shall return a value  of  zero
39       and  the  attributes  of  the  message queue shall have been changed as
40       specified.
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42       Otherwise, the message queue attributes shall  be  unchanged,  and  the
43       function  shall  return  a  value  of  -1 and set errno to indicate the
44       error.
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ERRORS

47       The mq_setattr() function shall fail if:
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49       EBADF  The mqdes argument is not a valid message queue descriptor.
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52       The following sections are informative.
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EXAMPLES

55       None.
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APPLICATION USAGE

58       None.
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RATIONALE

61       None.
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FUTURE DIRECTIONS

64       None.
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SEE ALSO

67       mq_open() , mq_send() , mq_timedsend() , msgctl() , msgget() , msgrcv()
68       ,  msgsnd()  ,  the  Base  Definitions  volume of IEEE Std 1003.1-2001,
69       <mqueue.h>
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72       Portions of this text are reprinted and reproduced in  electronic  form
73       from IEEE Std 1003.1, 2003 Edition, Standard for Information Technology
74       -- Portable Operating System Interface (POSIX),  The  Open  Group  Base
75       Specifications  Issue  6,  Copyright  (C) 2001-2003 by the Institute of
76       Electrical and Electronics Engineers, Inc and The Open  Group.  In  the
77       event of any discrepancy between this version and the original IEEE and
78       The Open Group Standard, the original IEEE and The Open Group  Standard
79       is  the  referee document. The original Standard can be obtained online
80       at http://www.opengroup.org/unix/online.html .
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84IEEE/The Open Group                  2003                        MQ_SETATTR(P)
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