1.\" -*- nroff -*- 2.\" 3.\" Copyright (c) 2000 Jonathan M. Bresler 4.\" 5.\" All rights reserved. 6.\" 7.\" This program is free software. 8.\" 9.\" Redistribution and use in source and binary forms, with or without 10.\" modification, are permitted provided that the following conditions 11.\" are met: 12.\" 1. Redistributions of source code must retain the above copyright 13.\" notice, this list of conditions and the following disclaimer. 14.\" 2. Redistributions in binary form must reproduce the above copyright 15.\" notice, this list of conditions and the following disclaimer in the 16.\" documentation and/or other materials provided with the distribution. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE DEVELOPERS ``AS IS'' AND ANY EXPRESS OR 19.\" IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 20.\" OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 21.\" IN NO EVENT SHALL THE DEVELOPERS BE LIABLE FOR ANY DIRECT, INDIRECT, 22.\" INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 23.\" NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24.\" DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25.\" THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26.\" (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 27.\" THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28.\" 29.\" $FreeBSD: src/share/man/man9/KASSERT.9,v 1.1.2.4 2001/07/21 09:16:54 schweikh Exp $ 30.\" 31.Dd January 14, 2000 32.Os 33.Dt KASSERT 9 34.Sh NAME 35.Nm KASSERT 36.Nd kernel expression verification macro 37.Sh SYNOPSIS 38.Cd options INVARIANTS 39.Fn KASSERT expression "const char *msg" 40.Sh DESCRIPTION 41In a kernel compiled with "options INVARIANTS", 42the 43.Fn KASSERT 44macro tests the given 45.Ar expression 46and if it is false, 47calls the 48.Fn panic 49syscall, terminating the running system. 50.Pp 51In a kernel that does not have "options INVARIANTS", 52the 53.Fn KASSERT 54macro is defined to be a no-op. 55.Sh EXAMPLES 56The kernel function 57.Fn vput 58must not be called with a NULL pointer. 59.Bd -literal -offset indent 60void 61vput(vp) 62 struct vnode *vp; 63{ 64 struct proc *p = curproc; 65 KASSERT(vp != NULL, ("vput: null vp")); 66 ... 67} 68.Ed 69.Sh SEE ALSO 70.Xr config 8 , 71.Xr panic 9 72.Sh AUTHORS 73This manual page was written by 74.An Jonathan M. Bresler 75.Aq jmb@FreeBSD.org . 76