NetBSD/lib/libpthread/pthread_attr_getinheritsched.3

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.\" $NetBSD: pthread_attr_getinheritsched.3,v 1.4 2017/10/22 16:37:24 abhinav Exp $
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.\" Copyright (c) 2010 Jukka Ruohonen <jruohonen@iki.fi>
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.Dd May 10, 2013
.Dt PTHREAD_ATTR_GETINHERITSCHED 3
.Os
.Sh NAME
.Nm pthread_attr_getinheritsched ,
.Nm pthread_attr_setinheritsched
.Nd get and set
.Dq inheritsched
attribute
.Sh LIBRARY
.Lb libpthread
.Sh SYNOPSIS
.In pthread.h
.Ft int
.Fn pthread_attr_getinheritsched \
"const pthread_attr_t * restrict attr" "int * restrict inheritsched"
.Ft int
.Fn pthread_attr_setinheritsched "pthread_attr_t *attr" "int inheritsched"
.Sh DESCRIPTION
The
.Fn pthread_attr_getinheritsched
and
.Fn pthread_attr_setinheritsched
functions get and set, respectively, the inherit scheduler attribute,
.Fa inheritsched ,
in the
.Fa attr
object.
The
.Fa inheritsched
parameter specifies whether a tread created by using
.Fa attr
will obtain its scheduling attributes directly from
.Fa attr
or whether it will inherit these from the calling thread.
.Pp
Two values are possible for
.Fa inheritsched :
.Bl -tag -width PTHREAD_EXPLICIT_SCHED -offset indent
.It Dv PTHREAD_INHERIT_SCHED
The thread scheduling attributes will be
inherited from the creating thread and the ones in
.Fa attr
are ignored.
.It Dv PTHREAD_EXPLICIT_SCHED
The thread scheduling attributes will be set to the corresponding values in
.Fa attr .
.El
.Pp
The following thread scheduling attributes are affected by
.Fa inheritsched :
.Bl -bullet -offset indent
.It
Scheduling policy; see
.Xr pthread_attr_setschedpolicy 3 .
.It
Scheduling parameter; see
.Xr pthread_attr_getschedparam 3 .
.It
Scheduling contention scope; see
.Xr pthread_attr_getscope 3 .
.El
.Sh RETURN VALUES
If successful, both functions return 0.
Otherwise, an error number is returned to indicate the error.
.Sh COMPATIBILITY
The standard leaves it unspecified which (if any) is the default
inherit scheduler attribute in a newly initialized attribute object.
.Sh ERRORS
No errors are defined for
.Fn pthread_attr_getinheritsched .
.Pp
The
.Fn pthread_attr_setinheritsched
function may fail if:
.Bl -tag -width Er
.It Bq Er EINVAL
The value specified by
.Fa inheritsched
is invalid.
.El
.Sh SEE ALSO
.Xr pthread_attr 3
.Sh STANDARDS
Both functions conform to
.St -p1003.1-2008 .