pthread_getschedparam.3   [plain text]

.\" Copyright (C) 2000 Jason Evans <jasone@FreeBSD.org>.
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.\" $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