'\" te
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.TH mq_getattr 3C "5 Feb 2008" "SunOS 5.11" "Standard C Library Functions"
.SH NAME
mq_getattr \- get message queue attributes
.SH SYNOPSIS
.LP
.nf
#include <mqueue.h>

\fBint\fR \fBmq_getattr\fR(\fBmqd_t\fR \fImqdes\fR, \fBstruct mq_attr *\fR\fImqstat\fR);
.fi

.SH DESCRIPTION
.sp
.LP
The \fImqdes\fR argument specifies a message queue descriptor. The
\fBmq_getattr()\fR function is used to get status information and attributes of
the message queue and the open message queue description associated with the
message queue descriptor. The results are returned in the \fImq_attr\fR
structure referenced by the \fImqstat\fR argument.
.sp
.LP
Upon return, the following members will have the values associated with the
open message queue description as set when the message queue was opened and as
modified by subsequent \fBmq_setattr\fR(3C) calls:
.sp
.ne 2
.mk
.na
\fB\fBmq_flags\fR\fR
.ad
.RS 12n
.rt  
message queue flags
.RE

.sp
.LP
The following attributes of the message queue are returned as set at message
queue creation:
.sp
.ne 2
.mk
.na
\fB\fBmq_maxmsg\fR\fR
.ad
.RS 14n
.rt  
maximum number of messages
.RE

.sp
.ne 2
.mk
.na
\fB\fBmq_msgsize\fR\fR
.ad
.RS 14n
.rt  
maximum message size
.RE

.sp
.ne 2
.mk
.na
\fB\fBmq_curmsgs\fR\fR
.ad
.RS 14n
.rt  
number of messages currently on the queue.
.RE

.SH RETURN VALUES
.sp
.LP
Upon successful completion, the \fBmq_getattr()\fR function returns \fB0\fR.
Otherwise, the function returns \fB\(mi1\fR and sets \fBerrno\fR to indicate
the error.
.SH ERRORS
.sp
.LP
The  \fBmq_getattr()\fR function will fail if:
.sp
.ne 2
.mk
.na
\fB\fBEBADF\fR\fR
.ad
.RS 10n
.rt  
The \fImqdes\fR argument is not a valid message queue descriptor.
.RE

.sp
.ne 2
.mk
.na
\fB\fBENOSYS\fR\fR
.ad
.RS 10n
.rt  
The \fBmq_getattr()\fR function is not supported by the system.
.RE

.SH ATTRIBUTES
.sp
.LP
See \fBattributes\fR(5) for descriptions of the following attributes:
.sp

.sp
.TS
tab() box;
lw(2.75i) |lw(2.75i) 
lw(2.75i) |lw(2.75i) 
.
\fBATTRIBUTE TYPE\fR\fBATTRIBUTE VALUE\fR
_
Interface StabilityCommitted
_
MT-LevelMT-Safe
_
StandardSee \fBstandards\fR(5).
.TE

.SH SEE ALSO
.sp
.LP
\fBmsgctl\fR(2), \fBmsgget\fR(2), \fBmsgrcv\fR(2), \fBmsgsnd\fR(2),
\fBmqueue.h\fR(3HEAD), \fBmq_open\fR(3C), \fBmq_send\fR(3C),
\fBmq_setattr\fR(3C), \fBattributes\fR(5), \fBstandards\fR(5)
.SH NOTES
.sp
.LP
Solaris 2.6 was the first release to support the Asynchronous Input and Output
option. Prior to this release, this function always returned \fB\(mi1\fR and
set \fBerrno\fR to \fBENOSYS\fR.