1.\" $NetBSD: munmap.2,v 1.21 2014/05/30 16:11:01 njoly Exp $ 2.\" 3.\" Copyright (c) 1991, 1993 4.\" The Regents of the University of California. 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.\" 3. Neither the name of the University nor the names of its contributors 15.\" may be used to endorse or promote products derived from this software 16.\" without specific prior written permission. 17.\" 18.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 19.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 20.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 21.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 22.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 23.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 24.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 25.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 26.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 27.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 28.\" SUCH DAMAGE. 29.\" 30.\" @(#)munmap.2 8.3 (Berkeley) 5/27/94 31.\" 32.Dd May 27, 1994 33.Dt MUNMAP 2 34.Os 35.Sh NAME 36.Nm munmap 37.Nd remove a mapping 38.Sh LIBRARY 39.Lb libc 40.Sh SYNOPSIS 41.In sys/mman.h 42.Ft int 43.Fn munmap "void *addr" "size_t len" 44.Sh DESCRIPTION 45The 46.Fn munmap 47system call 48deletes the mappings for the specified address range, 49and causes further references to addresses within the range 50to generate invalid memory references. 51.Sh RETURN VALUES 52Upon successful completion, 53.Nm munmap 54returns zero. 55Otherwise, a value of \-1 is returned and 56.Va errno 57is set to indicate the error. 58.Sh ERRORS 59.Fn munmap 60will fail if: 61.Bl -tag -width Er 62.It Bq Er EINVAL 63The 64.Fa addr 65parameter was not page aligned, or 66some part of the region being unmapped is outside the 67valid address range for a process. 68.El 69.Sh SEE ALSO 70.Xr madvise 2 , 71.Xr mincore 2 , 72.Xr mlock 2 , 73.Xr mmap 2 , 74.Xr mprotect 2 , 75.Xr msync 2 , 76.Xr getpagesize 3 77.Sh STANDARDS 78The 79.Fn munmap 80function conforms to 81.St -p1003.1b-93 . 82.Sh HISTORY 83The 84.Fn munmap 85function first appeared in 86.Bx 4.4 . 87