1.\" $OpenBSD: pthread_schedparam.3,v 1.2 2007/05/31 19:19:37 jmc Exp $
2.\" Copyright (C) 2000 Jason Evans <jasone@freebsd.org>.
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29.\" $FreeBSD: src/lib/libc_r/man/pthread_schedparam.3,v 1.4 2001/07/15 07:53:27 dd Exp $
30.Dd $Mdocdate: May 31 2007 $
31.Dt PTHREAD_SCHEDPARAM 3
32.Os
33.Sh NAME
34.Nm pthread_setschedparam ,
35.Nm pthread_getschedparam
36.Nd thread scheduling parameter manipulation
37.Sh SYNOPSIS
38.Fd #include <pthread.h>
39.Ft int
40.Fn pthread_setschedparam "pthread_t thread" "int policy" "const struct sched_param *param"
41.Ft int
42.Fn pthread_getschedparam "pthread_t thread" "int *policy" "struct sched_param *param"
43.Sh DESCRIPTION
44The
45.Fn pthread_setschedparam
46and
47.Fn pthread_getschedparam
48functions set and get the scheduling parameters of individual threads.
49The scheduling policy for a thread can either be
50.Dv SCHED_FIFO
51(first in, first out) or
52.Dv SCHED_RR
53(round-robin).
54The thread priority (accessed via
55.Va param->sched_priority )
56must be at least
57.Dv PTHREAD_MIN_PRIORITY
58and no more than
59.Dv PTHREAD_MAX_PRIORITY .
60.Sh RETURN VALUES
61If successful, these functions return 0.
62Otherwise, an error number is returned to indicate the error.
63.Sh ERRORS
64.Fn pthread_setschedparam
65will fail if:
66.Bl -tag -width Er
67.It Bq Er EINVAL
68Invalid value for
69.Va policy .
70.It Bq Er ENOTSUP
71Invalid value for scheduling parameters.
72.It Bq Er ESRCH
73Non-existent thread
74.Va thread .
75.El
76.Pp
77.Fn pthread_getschedparam
78will fail if:
79.Bl -tag -width Er
80.It Bq Er ESRCH
81Non-existent thread
82.Va thread .
83.El
84.Sh STANDARDS
85.Fn pthread_setschedparam
86and
87.Fn pthread_getschedparam
88conform to
89.St -susv2
90