1.\" $FreeBSD: src/lib/libc/sys/sched_get_priority_max.2,v 1.3.2.9 2001/12/14 18:34:01 ru Exp $ 2.\" $DragonFly: src/lib/libc/sys/sched_get_priority_max.2,v 1.5 2008/05/25 18:11:47 swildner Exp $ 3.\" Copyright (c) 1998 HD Associates, Inc. 4.\" All rights reserved. 5.\" 6.\" Redistribution and use in source and binary forms, with or without 7.\" modification, are permitted provided that the following conditions 8.\" are met: 9.\" 1. Redistributions of source code must retain the above copyright 10.\" notice, this list of conditions and the following disclaimer. 11.\" 2. Redistributions in binary form must reproduce the above copyright 12.\" notice, this list of conditions and the following disclaimer in the 13.\" documentation and/or other materials provided with the distribution. 14.\" 15.\" THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 16.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18.\" ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 19.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25.\" SUCH DAMAGE. 26.\" 27.Dd March 12, 1998 28.Dt SCHED_GET_PRIORITY_MAX 2 29.Os 30.Sh NAME 31.Nm sched_get_priority_max , 32.Nm sched_get_priority_min , 33.Nm sched_rr_get_interval 34.Nd get scheduling parameter limits 35.Sh LIBRARY 36.Lb libc 37.Sh SYNOPSIS 38.In sched.h 39.Ft int 40.Fn sched_get_priority_max "int policy" 41.Ft int 42.Fn sched_get_priority_min "int policy" 43.Ft int 44.Fn sched_rr_get_interval "pid_t pid" "struct timespec *interval" 45.Sh DESCRIPTION 46The 47.Fn sched_get_priority_max 48and 49.Fn sched_get_priority_min 50functions return the appropriate maximum or minimum, respectively, 51for the scheduling policy specified by 52.Fa policy . 53The 54.Fn sched_rr_get_interval 55function updates the 56.Fa timespec 57structure referenced by the 58.Fa interval 59argument to contain the current execution time limit (i.e., time 60quantum) for the process specified by 61.Fa pid . 62If 63.Fa pid 64is zero, the current execution time limit for the calling process is 65returned. 66.Pp 67The value of 68.Fa policy 69should be one of the scheduling policy values defined in 70.In sched.h : 71.Bl -tag -width ".Dv SCHED_OTHER" 72.It Dv SCHED_FIFO 73First-in-first-out fixed priority scheduling with no round robin scheduling; 74.It Dv SCHED_OTHER 75The standard time sharing scheduler; 76.It Dv SCHED_RR 77Round-robin scheduling across same priority processes. 78.El 79.Sh RETURN VALUES 80If successful, the 81.Fn sched_get_priority_max 82and 83.Fn sched_get_priority_min 84functions shall return the appropriate maximum or minimum values, 85respectively. If unsuccessful, they shall return a value of -1 and set 86.Va errno 87to indicate the error. 88.Pp 89.Rv -std sched_rr_get_interval 90.Sh ERRORS 91On failure 92.Va errno 93will be set to the corresponding value: 94.Bl -tag -width Er 95.It Bq Er EINVAL 96The value of the 97.Fa policy 98parameter does not represent a defined scheduling policy. 99.It Bq Er ENOSYS 100The 101.Fn sched_get_priority_max , 102.Fn sched_get_priority_min , 103and 104.Fn sched_rr_get_interval 105functions are not supported by the implementation. 106.It Bq Er ESRCH 107No process can be found corresponding to that specified by 108.Fa pid . 109.El 110.Sh SEE ALSO 111.Xr sched_getparam 2 , 112.Xr sched_getscheduler 2 , 113.Xr sched_setparam 2 , 114.Xr sched_setscheduler 2 115.Sh STANDARDS 116The 117.Fn sched_setscheduler 118and 119.Fn sched_getscheduler 120functions conform to 121.St -p1003.1b-93 . 122