pthread_rwlockattr_getpshared.3   [plain text]


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.\" $FreeBSD: src/lib/libc_r/man/pthread_rwlockattr_getpshared.3,v 1.8 2001/10/01 16:09:09 ru Exp $
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.Dd March 22, 1999
.Dt PTHREAD_RWLOCKATTR_GETPSHARED 3
.Os
.Sh NAME
.Nm pthread_rwlockattr_getpshared
.Nd get the process shared attribute
.Sh SYNOPSIS
.In pthread.h
.Ft int
.Fn pthread_rwlockattr_getpshared "const pthread_rwlockattr_t *attr" "int *pshared"
.Sh DESCRIPTION
The
.Fn pthread_rwlockattr_getpshared
function is used to get the process shared setting of a read/write
lock attribute object.  The setting is returned via
.Fa pshared ,
and may be one of two values:
.Bl -tag -width PTHREAD_PROCESS_PRIVATE
.It Dv PTHREAD_PROCESS_SHARED
Any thread of any process that has access to the memory where the
read/write lock resides can manipulate the lock.
.It Dv PTHREAD_PROCESS_PRIVATE
Only threads created within the same process as the thread that
initialized the read/write lock can manipulate the lock.  This is
the default value.
.El
.Sh RETURN VALUES
If successful, the
.Fn pthread_rwlockattr_getpshared
function will return zero.  Otherwise an error number will be returned
to indicate the error.
.Sh SEE ALSO
.Xr pthread_rwlockattr_init 3 ,
.Xr pthread_rwlockattr_setpshared 3 ,
.Xr pthread_rwlock_init 3
.Sh STANDARDS
The
.Fn pthread_rwlockattr_getpshared
function is expected to conform to
.St -susv2 .
.Sh ERRORS
.Fn pthread_rwlockattr_getpshared
may fail if:
.Bl -tag -width Er
.It Bq Er EINVAL
The value specified by
.Fa attr
is invalid.
.El
.Sh HISTORY
The
.Fn pthread_rwlockattr_getpshared
function first appeared in
.Fx 3.0 .