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mq_setattr(3rt) [sunos man page]

mq_setattr(3RT) 					    Realtime Library Functions						   mq_setattr(3RT)

NAME

       mq_setattr - set/get message queue attributes

SYNOPSIS

       cc [ flag... ] file... -lrt [ library... ]
       #include <mqueue.h>

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

DESCRIPTION

       The  mq_setattr()  function  is	used  to set attributes associated with the open message queue description referenced by the message queue
       descriptor specified by mqdes.

       The message queue attributes corresponding to the following members defined in the mq_attr structure are set to the specified  values  upon
       successful completion of mq_setattr():

       mq_flags        The value of this member is either 0 or	O_NONBLOCK.

       The values of mq_maxmsg, mq_msgsize, and mq_curmsgs are ignored by mq_setattr().

       If  omqstat  is non-NULL, mq_setattr() stores, in the location referenced by omqstat, the previous message queue attributes and the current
       queue status. These values are the same as would be returned by a call to mq_getattr() at that point.

RETURN VALUES

       Upon successful completion, mq_setattr() returns 0 and the attributes of the message queue will have been changed as specified.	Otherwise,
       the message queue attributes are unchanged, and the function returns -1 and sets errno to indicate the error.

ERRORS

       The mq_setattr() function will fail if:

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

       ENOSYS	       The mq_setattr() function is not supported by the system.

ATTRIBUTES

       See attributes(5) for descriptions of the following attributes:

       +-----------------------------+-----------------------------+
       |      ATTRIBUTE TYPE	     |	    ATTRIBUTE VALUE	   |
       +-----------------------------+-----------------------------+
       |Interface Stability	     |Standard			   |
       +-----------------------------+-----------------------------+
       |MT-Level		     |MT-Safe			   |
       +-----------------------------+-----------------------------+

SEE ALSO

       msgctl(2),  msgget(2),  msgrcv(2), msgsnd(2), mq_getattr(3RT), mq_open(3RT), mq_receive(3RT), mq_send(3RT), mqueue.h(3HEAD), 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.

SunOS 5.10							    14 May 2002 						   mq_setattr(3RT)

Check Out this Related Man Page

mq_getattr(3)						     Library Functions Manual						     mq_getattr(3)

NAME

       mq_getattr - Returns the status and attributes of a message queue (P1003.1b)

LIBRARY

       Realtime Library (librt.so, librt.a)

SYNOPSIS

       #include <mqueue.h>

       int mq_getattr (
       mqd_t mqdes,
       struct mq_attr *mqstat);

PARAMETERS

       mqdes	   Specifies the message queue descriptor whose attributes are obtained.

       *mqstat	   Specifies  a  pointer  to a structure that is updated to contain the values that were set when the message queue was created or
		   modified by a call to the mq_setattr function.

       When the mq_getattr function returns, the following three members of the mq_attr structure specified by mqstat will have  the  values  that
       were set when the message queue was created, but with modifications made by subsequent calls to the mq_setattr function:

	  o  The mq_maxmsg member specifies the maximum number of messages that can be held in the queue specified by the mqdes argument.

	  o  The mq_msgsize member specifies the maximum size of any message in the queue.

	  o  The mq_flags member specifies whether the message operation is blocking or nonblocking (MQ_NONBLOCK).

       The mq_curmsgs member of the mq_attr structure indicates the number of messages currently on the queue.

DESCRIPTION

       The mq_getattr function returns the status and attributes of a message queue. Use the mq_setattr function to set message queue attributes.

RETURN VALUES

       On  successful completion, the function returns the value 0 (zero); otherwise, the function returns the value -1 and sets errno to indicate
       the error.

ERRORS

       The mq_getattr function fails under the following conditions:

       [EBADF]	      The fildes argument is an invalid file descriptor.

       [EINVAL]       The mqstat argument is a null pointer.

RELATED INFORMATION

       Functions: mq_open(3), mq_receive(3), mq_send(3), mq_setattr(3)

       Guide to Realtime Programming delim off

																     mq_getattr(3)
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