freebsd-dev/share/man/man3/pthread_schedparam.3

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.Dd May 1, 2000
.Dt PTHREAD_SCHEDPARAM 3
.Os
.Sh NAME
.Nm pthread_setschedparam ,
.Nm pthread_getschedparam
.Nd thread scheduling parameter manipulation
.Sh LIBRARY
.Lb libc_r
.Lb libpthread
.Lb libthr
.Sh SYNOPSIS
.In pthread.h
.Ft int
.Fn pthread_setschedparam "pthread_t thread" "int policy" "const struct sched_param *param"
.Ft int
.Fn pthread_getschedparam "pthread_t thread" "int *policy" "struct sched_param *param"
.Sh DESCRIPTION
The
.Fn pthread_setschedparam
and
.Fn pthread_getschedparam
functions set and get 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
The
.Fn pthread_setschedparam
function 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
.Pp
The
.Fn pthread_getschedparam
function will fail if:
.Bl -tag -width Er
.It Bq Er ESRCH
Non-existent thread
.Va thread .
.El
.Sh STANDARDS
The
.Fn pthread_setschedparam
and
.Fn pthread_getschedparam
functions conform to
.St -susv2