1.\" $NetBSD: param.3,v 1.4 2011/04/10 10:02:34 jruoho Exp $ 2.\" 3.\" Copyright (c) 2011 Jukka Ruohonen <jruohonen@iki.fi> 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 NETBSD FOUNDATION, INC. AND CONTRIBUTORS 16.\" ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 17.\" TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 18.\" PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 19.\" BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 20.\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 21.\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 22.\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 23.\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 24.\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 25.\" POSSIBILITY OF SUCH DAMAGE. 26.\" 27.Dd April 10, 2011 28.Dt PARAM 3 29.Os 30.Sh NAME 31.Nm param 32.Nd common parameters 33.Sh SYNOPSIS 34.In sys/param.h 35.Ft size 36.Fn MAX "size a" "size b" 37.Ft size 38.Fn MIN "size a" "size b" 39.Sh DESCRIPTION 40The 41.In sys/param.h 42header includes some common definitions and macros specific to 43.Nx . 44The header is perhaps best characterized as a kernel equivalent of 45.In sys/types.h . 46The following list summarizes the provided definitions and macros. 47.Bl -bullet -offset indent 48.It 49First and foremost, the header defines the version of 50.Nx . 51This is defined as 52.Bd -literal -offset indent 53#define __NetBSD_Version__ 599004800 /* 5.99.48 */ 54.Ed 55.Pp 56The general format is 57.Dq MMmmrrpp00 , 58where 59.Sq MM 60and 61.Sq mm 62denote the major and minor version, respectively, 63.Sq rr 64is provided for compatibility, and 65.Sq pp 66defines the patch level. 67.It 68Common utility macros such as 69.Fn MAX 70and 71.Fn MIN 72as well as more specific macros such as 73.Xr STACK 9 , 74.Xr ctod 9 , 75.Xr mstohz 9 , 76.Xr roundup 9 , 77and 78.Xr setbit 9 . 79.It 80Numerous miscellaneous definitions such as limits, 81constants for the kernel 82.Xr memoryallocators 9 , 83scale factors used by the scheduler, 84.Xr kthread 9 85priorities, and many others. 86.It 87Definitions provided for historical and compatibility reasons. 88Examples range from definitions such as 89.Dq #define BSD 90to old priority levels used in the kernel. 91.El 92.Sh SEE ALSO 93.Xr bitops 3 , 94.Xr cdefs 3 , 95.Xr types 3 , 96.Xr unistd 3 97.Sh HISTORY 98A 99.In param.h 100header appeared already in the 101.At v4 . 102