'\" te
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.TH pthread_rwlockattr_init 3C "11 Jan 2012" "SunOS 5.11" "Standard C Library Functions"
.SH NAME
pthread_rwlockattr_init, pthread_rwlockattr_destroy \- initialize or destroy read-write lock attributes object
.SH SYNOPSIS
.LP
.nf
cc -mt [ \fIflag\fR... ] \fIfile\fR... [ \fIlibrary\fR... ]
#include <pthread.h>

\fBint\fR \fBpthread_rwlockattr_init\fR(\fBpthread_rwlockattr_t\fR \fI*attr\fR);
.fi

.LP
.nf
\fBint\fR \fBpthread_rwlockattr_destroy\fR(\fBpthread_rwlockattr_t\fR \fI*attr\fR);
.fi

.SH DESCRIPTION
.sp
.LP
The \fBpthread_rwlockattr_init()\fR function initializes a read-write lock attributes object \fIattr\fR with the default value for all of the attributes defined by the implementation.
.sp
.LP
Results are undefined if \fBpthread_rwlockattr_init()\fR is called specifying an already initialized read-write lock attributes object.
.sp
.LP
After a read-write lock attributes object has been used to initialize one or more read-write locks, any function affecting the attributes object (including destruction) does not affect any previously initialized read-write locks.
.sp
.LP
The \fBpthread_rwlockattr_destroy()\fR function destroys a read-write lock attributes object. The effect of subsequent use of the object is undefined until the object is re-initialized by another call to \fBpthread_rwlockattr_init()\fR. An implementation can cause \fBpthread_rwlockattr_destroy()\fR to set the object referenced by \fIattr\fR to an invalid value.
.SH RETURN VALUES
.sp
.LP
If successful, the \fBpthread_rwlockattr_init()\fR and \fBpthread_rwlockattr_destroy()\fR functions return \fB0\fR. Otherwise, an error number is returned to indicate the error.
.SH ERRORS
.sp
.LP
The \fBpthread_rwlockattr_init()\fR function will fail if:
.sp
.ne 2
.mk
.na
\fB\fBENOMEM\fR\fR
.ad
.RS 10n
.rt  
Insufficient memory exists to initialize the read-write lock attributes object.
.RE

.sp
.LP
The \fBpthread_rwlockattr_destroy()\fR function may fail if:
.sp
.ne 2
.mk
.na
\fB\fBEINVAL\fR\fR
.ad
.RS 10n
.rt  
The value specified by \fIattr\fR is invalid.
.RE

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

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

.SH SEE ALSO
.sp
.LP
\fBpthread_rwlock_init\fR(3C), \fBpthread_rwlock_rdlock\fR(3C), \fBpthread_rwlock_unlock\fR(3C), \fBpthread_rwlock_wrlock\fR(3C), \fBpthread_rwlockattr_getpshared\fR(3C), \fBattributes\fR(5), \fBstandards\fR(5)