.\" $NetBSD: munmap.2,v 1.5 1995/02/27 12:35:03 cgd Exp $ .\" .\" Copyright (c) 1991, 1993 .\" The Regents of the University of California. All rights reserved. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions .\" are met: .\" 1. Redistributions of source code must retain the above copyright .\" notice, this list of conditions and the following disclaimer. .\" 2. Redistributions in binary form must reproduce the above copyright .\" notice, this list of conditions and the following disclaimer in the .\" documentation and/or other materials provided with the distribution. .\" 3. All advertising materials mentioning features or use of this software .\" must display the following acknowledgement: .\" This product includes software developed by the University of .\" California, Berkeley and its contributors. .\" 4. Neither the name of the University nor the names of its contributors .\" may be used to endorse or promote products derived from this software .\" without specific prior written permission. .\" .\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND .\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE .\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL .\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS .\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) .\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT .\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY .\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF .\" SUCH DAMAGE. .\" .\" @(#)munmap.2 8.2 (Berkeley) 4/15/94 .\" .Dd April 15, 1994 .Dt MUNMAP 2 .Os .Sh NAME .Nm munmap .Nd remove a mapping .Sh SYNOPSIS .Fd #include <sys/mman.h> .Ft int .Fo munmap .Fa "void *addr" .Fa "size_t len" .Fc .Sh DESCRIPTION The .Fn munmap system call deletes the mappings for the specified address range, causing further references to addresses within the range to generate invalid memory references. .Sh RETURN VALUES Upon successful completion, .Nm munmap returns zero. Otherwise, a value of -1 is returned and .Va errno is set to indicate the error. .Sh ERRORS .Fn Munmap will fail if: .Bl -tag -width Er .\" =========== .It Bq Er EINVAL The .Fa addr parameter was not page aligned (i.e., a multiple of the page size). .\" =========== .It Bq Er EINVAL The .Fa len parameter was negative or zero. .\" =========== .It Bq Er EINVAL Some part of the region being unmapped is not part of the currently valid address space. .El .Sh LEGACY SYNOPSIS .Fd #include <sys/types.h> .Fd #include <sys/mman.h> .Pp The include file .In sys/types.h is necessary. .Pp .Ft int .br .Fo munmap .Fa "caddr_t addr" .Fa "size_t len" .Fc ; .Pp The type of .Fa addr has changed. .Sh "SEE ALSO" .Xr getpagesize 3 , .Xr msync 2 , .Xr munmap 2 , .Xr mprotect 2 , .Xr madvise 2 , .Xr mincore 2 , .Xr compat 5 .Sh HISTORY The .Fn munmap function first appeared in 4.4BSD.