1.\" $NetBSD: munmap.2,v 1.13 1999/12/02 21:42:38 kleink 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. All advertising materials mentioning features or use of this software 15.\" must display the following acknowledgement: 16.\" This product includes software developed by the University of 17.\" California, Berkeley and its contributors. 18.\" 4. Neither the name of the University nor the names of its contributors 19.\" may be used to endorse or promote products derived from this software 20.\" without specific prior written permission. 21.\" 22.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32.\" SUCH DAMAGE. 33.\" 34.\" @(#)munmap.2 8.3 (Berkeley) 5/27/94 35.\" 36.Dd May 27, 1994 37.Dt MUNMAP 2 38.Os 39.Sh NAME 40.Nm munmap 41.Nd remove a mapping 42.Sh LIBRARY 43.Lb libc 44.Sh SYNOPSIS 45.Fd #include <sys/types.h> 46.Fd #include <sys/mman.h> 47.Ft int 48.Fn munmap "void *addr" "size_t len" 49.Sh DESCRIPTION 50The 51.Fn munmap 52system call 53deletes the mappings for the specified address range, 54and causes further references to addresses within the range 55to generate invalid memory references. 56.Sh RETURN VALUES 57Upon successful completion, 58.Nm munmap 59returns zero. 60Otherwise, a value of -1 is returned and 61.Va errno 62is set to indicate the error. 63.Sh ERRORS 64.Fn munmap 65will fail if: 66.Bl -tag -width Er 67.It Bq Er EINVAL 68The 69.Fa addr 70parameter was not page aligned, the 71.Fa len 72parameter was negative, or 73some part of the region being unmapped is outside the 74valid address range for a process. 75.El 76.Sh SEE ALSO 77.Xr madvise 2 , 78.Xr mincore 2 , 79.Xr mlock 2 , 80.Xr mmap 2 , 81.Xr mprotect 2 , 82.Xr msync 2 , 83.Xr getpagesize 3 84.Sh HISTORY 85The 86.Fn munmap 87function first appeared in 88.Bx 4.4 . 89