[apple/libc.git] / pthreads / pthread_getschedparam.3

.\" Copyright (C) 2000 Jason Evans <jasone@FreeBSD.org>.
.\" All rights reserved.
.\"
.\" Redistribution and use in source and binary forms, with or without
.\" modification, are permitted provided that the following conditions
.\" are met:
.\" 1. Redistributions of source code must retain the above copyright
.\"    notice(s), this list of conditions and the following disclaimer as
.\"    the first lines of this file unmodified other than the possible
.\"    addition of one or more copyright notices.
.\" 2. Redistributions in binary form must reproduce the above copyright
.\"    notice(s), this list of conditions and the following disclaimer in
.\"    the documentation and/or other materials provided with the
.\"    distribution.
.\"
.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
.\" EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
.\" PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
.\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
.\" BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
.\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
.\" OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
.\" EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
.\"
.\" $FreeBSD: src/lib/libc_r/man/pthread_schedparam.3,v 1.2.2.4 2001/08/17 15:42:52 ru Exp $
.Dd May 1, 2000
.Dt PTHREAD_SCHEDPARAM 3
.Os
.Sh NAME
.Nm pthread_getschedparam ,
.Nm pthread_setschedparam
.Nd thread scheduling parameter manipulation
.Sh SYNOPSIS
.Fd #include <pthread.h>
.Ft int
.Fo pthread_getschedparam
.Fa "pthread_t thread"
.Fa "int *restrict policy"
.Fa "struct sched_param *restrict param"
.Fc
.Ft int
.Fo pthread_setschedparam
.Fa "pthread_t thread"
.Fa "int policy"
.Fa "const struct sched_param *param"
.Fc
.Sh DESCRIPTION
The
.Fn pthread_getschedparam
and
.Fn pthread_setschedparam
functions get and set the scheduling parameters of individual threads.
The scheduling policy for a thread can either be
.Dv SCHED_FIFO
(first in, first out) or
.Dv SCHED_RR
(round-robin).
The thread priority (accessed via
.Va param->sched_priority )
must be at least
.Dv PTHREAD_MIN_PRIORITY
and no more than
.Dv PTHREAD_MAX_PRIORITY .
.Sh RETURN VALUES
If successful, these functions return 0.
Otherwise, an error number is returned to indicate the error.
.Sh ERRORS
.Fn pthread_getschedparam
will fail if:
.Bl -tag -width Er
.It Bq Er ESRCH
Non-existent thread
.Va thread .
.El
.Pp
.Fn pthread_setschedparam
will fail if:
.Bl -tag -width Er
.It Bq Er EINVAL
Invalid value for
.Va policy .
.It Bq Er ENOTSUP
Invalid value for scheduling parameters.
.It Bq Er ESRCH
Non-existent thread
.Va thread .
.El
.Sh STANDARDS
.Fn pthread_setschedparam
and
.Fn pthread_getschedparam
conform to
.St -susv2
Commit	Line	Data
5b2abdfb A	1	.\" Copyright (C) 2000 Jason Evans <jasone@FreeBSD.org>.
	2	.\" All rights reserved.
	3	.\"
	4	.\" Redistribution and use in source and binary forms, with or without
	5	.\" modification, are permitted provided that the following conditions
	6	.\" are met:
	7	.\" 1. Redistributions of source code must retain the above copyright
	8	.\" notice(s), this list of conditions and the following disclaimer as
	9	.\" the first lines of this file unmodified other than the possible
	10	.\" addition of one or more copyright notices.
	11	.\" 2. Redistributions in binary form must reproduce the above copyright
	12	.\" notice(s), this list of conditions and the following disclaimer in
	13	.\" the documentation and/or other materials provided with the
	14	.\" distribution.
	15	.\"
	16	.\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDER(S) ``AS IS'' AND ANY
	17	.\" EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	18	.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
	19	.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER(S) BE
	20	.\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	21	.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	22	.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
	23	.\" BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
	24	.\" WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
	25	.\" OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE,
	26	.\" EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	27	.\"
	28	.\" $FreeBSD: src/lib/libc_r/man/pthread_schedparam.3,v 1.2.2.4 2001/08/17 15:42:52 ru Exp $
	29	.Dd May 1, 2000
	30	.Dt PTHREAD_SCHEDPARAM 3
	31	.Os
	32	.Sh NAME
224c7076 A	33	.Nm pthread_getschedparam ,
224c7076 A	34	.Nm pthread_setschedparam
5b2abdfb A	35	.Nd thread scheduling parameter manipulation
	36	.Sh SYNOPSIS
	37	.Fd #include <pthread.h>
	38	.Ft int
224c7076 A	39	.Fo pthread_getschedparam
	40	.Fa "pthread_t thread"
	41	.Fa "int *restrict policy"
	42	.Fa "struct sched_param *restrict param"
	43	.Fc
5b2abdfb	44	.Ft int
224c7076 A	45	.Fo pthread_setschedparam
	46	.Fa "pthread_t thread"
	47	.Fa "int policy"
	48	.Fa "const struct sched_param *param"
	49	.Fc
5b2abdfb A	50	.Sh DESCRIPTION
5b2abdfb A	51	The
5b2abdfb	52	.Fn pthread_getschedparam
224c7076 A	53	and
	54	.Fn pthread_setschedparam
	55	functions get and set the scheduling parameters of individual threads.
5b2abdfb A	56	The scheduling policy for a thread can either be
	57	.Dv SCHED_FIFO
	58	(first in, first out) or
	59	.Dv SCHED_RR
	60	(round-robin).
	61	The thread priority (accessed via
	62	.Va param->sched_priority )
	63	must be at least
	64	.Dv PTHREAD_MIN_PRIORITY
	65	and no more than
	66	.Dv PTHREAD_MAX_PRIORITY .
	67	.Sh RETURN VALUES
	68	If successful, these functions return 0.
	69	Otherwise, an error number is returned to indicate the error.
	70	.Sh ERRORS
224c7076	71	.Fn pthread_getschedparam
5b2abdfb A	72	will fail if:
5b2abdfb A	73	.Bl -tag -width Er
5b2abdfb A	74	.It Bq Er ESRCH
	75	Non-existent thread
	76	.Va thread .
	77	.El
	78	.Pp
224c7076	79	.Fn pthread_setschedparam
5b2abdfb A	80	will fail if:
5b2abdfb A	81	.Bl -tag -width Er
224c7076 A	82	.It Bq Er EINVAL
	83	Invalid value for
	84	.Va policy .
	85	.It Bq Er ENOTSUP
	86	Invalid value for scheduling parameters.
5b2abdfb A	87	.It Bq Er ESRCH
	88	Non-existent thread
	89	.Va thread .
	90	.El
	91	.Sh STANDARDS
	92	.Fn pthread_setschedparam
	93	and
	94	.Fn pthread_getschedparam
	95	conform to
	96	.St -susv2