mirror of
https://git.FreeBSD.org/src.git
synced 2024-12-24 11:29:10 +00:00
123 lines
3.6 KiB
Groff
123 lines
3.6 KiB
Groff
.\" Copyright (c) 1998 HD Associates, Inc.
|
|
.\" 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, this list of conditions and the following disclaimer.
|
|
.\" 2. Redistributions in binary form must reproduce the above copyright
|
|
.\" notice, 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 AUTHOR AND CONTRIBUTORS ``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 AUTHOR OR CONTRIBUTORS 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.
|
|
.\"
|
|
.\" $FreeBSD$
|
|
.\"
|
|
.Dd March 12, 1998
|
|
.Dt SCHED_GET_PRIORITY_MAX 2
|
|
.Os
|
|
.Sh NAME
|
|
.Nm sched_get_priority_max ,
|
|
.Nm sched_get_priority_min ,
|
|
.Nm sched_rr_get_interval
|
|
.Nd get scheduling parameter limits
|
|
.Sh LIBRARY
|
|
.Lb libc
|
|
.Sh SYNOPSIS
|
|
.In sched.h
|
|
.Ft int
|
|
.Fn sched_get_priority_max "int policy"
|
|
.Ft int
|
|
.Fn sched_get_priority_min "int policy"
|
|
.Ft int
|
|
.Fn sched_rr_get_interval "pid_t pid" "struct timespec *interval"
|
|
.Sh DESCRIPTION
|
|
The
|
|
.Fn sched_get_priority_max
|
|
and
|
|
.Fn sched_get_priority_min
|
|
system calls return the appropriate maximum or minimum, respectively,
|
|
for the scheduling policy specified by
|
|
.Fa policy .
|
|
The
|
|
.Fn sched_rr_get_interval
|
|
system call updates the
|
|
.Fa timespec
|
|
structure referenced by the
|
|
.Fa interval
|
|
argument to contain the current execution time limit (i.e., time
|
|
quantum) for the process specified by
|
|
.Fa pid .
|
|
If
|
|
.Fa pid
|
|
is zero, the current execution time limit for the calling process is
|
|
returned.
|
|
.Pp
|
|
The value of
|
|
.Fa policy
|
|
should be one of the scheduling policy values defined in
|
|
.Fa <sched.h> :
|
|
.Bl -tag -width [SCHED_OTHER]
|
|
.It Bq Er SCHED_FIFO
|
|
First-in-first-out fixed priority scheduling with no round robin scheduling;
|
|
.It Bq Er SCHED_OTHER
|
|
The standard time sharing scheduler;
|
|
.It Bq Er SCHED_RR
|
|
Round-robin scheduling across same priority processes.
|
|
.El
|
|
.Sh RETURN VALUES
|
|
If successful, the
|
|
.Fn sched_get_priority_max
|
|
and
|
|
.Fn sched_get_priority_min
|
|
system calls shall return the appropriate maximum or minimum values,
|
|
respectively. If unsuccessful, they shall return a value of -1 and set
|
|
.Fa errno
|
|
to indicate the error.
|
|
.Pp
|
|
.Rv -std sched_rr_get_interval
|
|
.Sh ERRORS
|
|
On failure
|
|
.Va errno
|
|
will be set to the corresponding value:
|
|
.Bl -tag -width Er
|
|
.It Bq Er EINVAL
|
|
The value of the
|
|
.Fa policy
|
|
argument does not represent a defined scheduling policy.
|
|
.It Bq Er ENOSYS
|
|
The
|
|
.Fn sched_get_priority_max ,
|
|
.Fn sched_get_priority_min ,
|
|
and
|
|
.Fn sched_rr_get_interval
|
|
system calls are not supported by the implementation.
|
|
.It Bq Er ESRCH
|
|
No process can be found corresponding to that specified by
|
|
.Fa pid .
|
|
.El
|
|
.Sh SEE ALSO
|
|
.Xr sched_getparam 2 ,
|
|
.Xr sched_getscheduler 2 ,
|
|
.Xr sched_setparam 2 ,
|
|
.Xr sched_setscheduler 2
|
|
.Sh STANDARDS
|
|
The
|
|
.Fn sched_get_priority_max ,
|
|
.Fn sched_get_priority_min ,
|
|
and
|
|
.Fn sched_rr_get_interval
|
|
system calls conform to
|
|
.St -p1003.1b-93 .
|