xref: /freebsd/share/man/man3/pthread_schedparam.3 (revision fa9896e082a1046ff4fbc75fcba4d18d1f2efc19)

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.Dd October 17, 2022
.Dt PTHREAD_SCHEDPARAM 3
.Os
.Sh NAME
.Nm pthread_setschedparam ,
.Nm pthread_getschedparam
.Nd thread scheduling parameter manipulation
.Sh LIBRARY
.Lb libpthread
.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 *restrict policy" "struct sched_param *restrict 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),
.Dv SCHED_RR
(round-robin), or
.Dv SCHED_OTHER
(timesharing).
Valid thread priorities (accessed via
.Va param->sched_priority )
must be within the range returned by the
.Xr sched_get_priority_min 2
and
.Xr sched_get_priority_max 2
system calls.
.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
.Fa policy .
.It Bq Er ENOTSUP
Invalid value for scheduling parameters.
.It Bq Er EPERM
The calling thread does not have sufficient privilege to perform the operation.
.It Bq Er ESRCH
Non-existent thread
.Fa thread .
.El
.Pp
The
.Fn pthread_getschedparam
function will fail if:
.Bl -tag -width Er
.It Bq Er ESRCH
Non-existent thread
.Fa thread .
.El
.Sh SEE ALSO
.Xr sched_get_priority_max 2 ,
.Xr sched_get_priority_min 2
.Sh STANDARDS
The
.Fn pthread_setschedparam
and
.Fn pthread_getschedparam
functions conform to
.St -susv2 .