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