1.\" Copyright (c) 1991, 1993 2.\" The Regents of the University of California. 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.\" 3. All advertising materials mentioning features or use of this software 13.\" must display the following acknowledgement: 14.\" This product includes software developed by the University of 15.\" California, Berkeley and its contributors. 16.\" 4. Neither the name of the University nor the names of its contributors 17.\" may be used to endorse or promote products derived from this software 18.\" without specific prior written permission. 19.\" 20.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30.\" SUCH DAMAGE. 31.\" 32.\" @(#)munmap.2 8.3 (Berkeley) 5/27/94 33.\" $FreeBSD: src/lib/libc/sys/munmap.2,v 1.10.2.5 2002/01/09 14:29:24 ru Exp $ 34.\" 35.Dd May 27, 1994 36.Dt MUNMAP 2 37.Os 38.Sh NAME 39.Nm munmap 40.Nd remove a mapping 41.Sh LIBRARY 42.Lb libc 43.Sh SYNOPSIS 44.In sys/types.h 45.In sys/mman.h 46.Ft int 47.Fn munmap "void *addr" "size_t len" 48.Sh DESCRIPTION 49The 50.Fn munmap 51system call 52deletes the mappings for the specified address range, 53and causes further references to addresses within the range 54to generate invalid memory references. 55.Sh RETURN VALUES 56.Rv -std munmap 57.Sh ERRORS 58.Fn Munmap 59will fail if: 60.Bl -tag -width Er 61.It Bq Er EINVAL 62The 63.Fa addr 64parameter was not page aligned, the 65.Fa len 66parameter was negative, or 67some part of the region being unmapped is outside the 68valid address range for a process. 69.El 70.Sh "SEE ALSO" 71.Xr madvise 2 , 72.Xr mincore 2 , 73.Xr mmap 2 , 74.Xr mprotect 2 , 75.Xr msync 2 , 76.Xr getpagesize 3 77.Sh HISTORY 78The 79.Fn munmap 80function first appeared in 81.Bx 4.4 . 82