NetBSD/lib/libpthread/pthread_condattr.3

.\" $NetBSD: pthread_condattr.3,v 1.9 2012/11/03 09:20:36 wiz Exp $
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.\" $FreeBSD: src/lib/libpthread/man/pthread_condattr.3,v 1.10 2002/09/16 19:29:28 mini Exp $
.Dd November 2, 2012
.Dt PTHREAD_CONDATTR 3
.Os
.Sh NAME
.Nm pthread_condattr_init
.Nd condition attribute operations
.Sh LIBRARY
.Lb libpthread
.Sh SYNOPSIS
.In pthread.h
.Ft int
.Fn pthread_condattr_init "pthread_condattr_t *attr"
.Ft int
.Fn pthread_condattr_setclock "pthread_condattr_t *attr" "clockid_t clock"
.Ft int
.Fn pthread_condattr_destroy "pthread_condattr_t *attr"
.Sh DESCRIPTION
Condition attribute objects are used to specify parameters to the
.Xr pthread_cond_init 3
function.
The
.Fn pthread_condattr_init
function initializes a condition attribute object with the default attributes
and the
.Fn pthread_condattr_destroy
function destroys a condition attribute object.
The
.Fn pthread_condattr_setclock
function sets the system clock to be used for time comparisons to
the one specified in
.Fa clock .
Valid clock values are
.Dv CLOCK_MONOTONIC
and
.Dv CLOCK_REALTIME
(the default).
.Sh RETURN VALUES
If successful, these functions return 0.
Otherwise, an error number is returned to indicate the error.
.Sh ERRORS
No errors are defined for
.Fn pthread_condattr_init .
.Pp
The
.Fn pthread_condattr_destroy
function may fail if:
.Bl -tag -width Er
.It Bq Er EINVAL
The value specified by
.Fa attr
is invalid.
.El
.Sh SEE ALSO
.Xr pthread_cond_init 3
.Sh STANDARDS
Both functions conform to
.St -p1003.1-2001 .
.Sh CAVEATS
The usefulness of the functions is questionable as the
.Nx
implementation does not support any non-default attributes.
These functions do not conform to the
.St -p1003.1-2008
revision of the standard, which mandates two additional attributes,
the clock attribute and the process-shared attribute.