NetBSD/lib/libpthread/pthread_condattr.3

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.\" $NetBSD: pthread_condattr.3,v 1.12 2017/03/28 17:42:52 maya 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 March 28, 2017
.Dt PTHREAD_CONDATTR 3
.Os
.Sh NAME
.Nm pthread_condattr_init ,
.Nm pthread_condattr_getpshared ,
.Nm pthread_condattr_setpshared ,
.Nm pthread_condattr_getclock ,
.Nm pthread_condattr_setclock
.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_getclock "const pthread_condattr_t *__restrict attr" \
"clockid_t * __restrict clock_id"
.Ft int
.Fn pthread_condattr_setclock "pthread_condattr_t *attr" "clockid_t clock"
.Ft int
.Fn pthread_condattr_destroy "pthread_condattr_t *attr"
.Ft int
.Fn pthread_condattr_getpshared "const pthread_condattr_t * __restrict attr" "int * __restrict pshared"
.Ft int
.Fn pshared_condattr_setpshared "pthread_condattr_t *attr" "int pshared"
.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_getclock
function shall obtain the value of the
.Fa clock
attributes object referenced by
.Fa attr .
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).
The
.Fn pthread_condattr_getpshared
function shall obtain the value of the process-shared attribute from the
attributes object referenced by
.Fa attr .
The
.Fn pthread_condattr_setpshared
function shall set the process-shared attribute in an initialized attributes
object referenced by
.Fa attr .
.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
.Pp
The
.Fn pthread_condattr_getclock
and
.Fn pthread_condattr_setclock
may fail if:
.Bl -tag -width Er
.It Bq Er EINVAL
The value specified by
.Fa attr
is invalid.
.El
.Pp
The
.Fn pthread_condattr_getpshared
and
.Fn pthread_condattr_setpshared
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 BUGS
The
.Fn pthread_condattr_getpshared
and
.Fn pthread_condattr_setpshared
functions are hidden by default since only thread shared attributes
are supported.