18269e767SBrooks Davis.\" Copyright (c) 1991, 1993 28269e767SBrooks Davis.\" The Regents of the University of California. All rights reserved. 38269e767SBrooks Davis.\" 48269e767SBrooks Davis.\" Redistribution and use in source and binary forms, with or without 58269e767SBrooks Davis.\" modification, are permitted provided that the following conditions 68269e767SBrooks Davis.\" are met: 78269e767SBrooks Davis.\" 1. Redistributions of source code must retain the above copyright 88269e767SBrooks Davis.\" notice, this list of conditions and the following disclaimer. 98269e767SBrooks Davis.\" 2. Redistributions in binary form must reproduce the above copyright 108269e767SBrooks Davis.\" notice, this list of conditions and the following disclaimer in the 118269e767SBrooks Davis.\" documentation and/or other materials provided with the distribution. 128269e767SBrooks Davis.\" 3. Neither the name of the University nor the names of its contributors 138269e767SBrooks Davis.\" may be used to endorse or promote products derived from this software 148269e767SBrooks Davis.\" without specific prior written permission. 158269e767SBrooks Davis.\" 168269e767SBrooks Davis.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 178269e767SBrooks Davis.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 188269e767SBrooks Davis.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 198269e767SBrooks Davis.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 208269e767SBrooks Davis.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 218269e767SBrooks Davis.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 228269e767SBrooks Davis.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 238269e767SBrooks Davis.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 248269e767SBrooks Davis.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 258269e767SBrooks Davis.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 268269e767SBrooks Davis.\" SUCH DAMAGE. 278269e767SBrooks Davis.\" 28*724e383bSEd Maste.Dd January 16, 2025 298269e767SBrooks Davis.Dt MUNMAP 2 308269e767SBrooks Davis.Os 318269e767SBrooks Davis.Sh NAME 328269e767SBrooks Davis.Nm munmap 338269e767SBrooks Davis.Nd remove a mapping 348269e767SBrooks Davis.Sh LIBRARY 358269e767SBrooks Davis.Lb libc 368269e767SBrooks Davis.Sh SYNOPSIS 378269e767SBrooks Davis.In sys/mman.h 388269e767SBrooks Davis.Ft int 398269e767SBrooks Davis.Fn munmap "void *addr" "size_t len" 408269e767SBrooks Davis.Sh DESCRIPTION 418269e767SBrooks DavisThe 428269e767SBrooks Davis.Fn munmap 438269e767SBrooks Davissystem call 448269e767SBrooks Davisdeletes the mappings and guards for the specified address range, 458269e767SBrooks Davisand causes further references to addresses within the range 468269e767SBrooks Davisto generate invalid memory references. 478269e767SBrooks Davis.Sh RETURN VALUES 488269e767SBrooks Davis.Rv -std munmap 498269e767SBrooks Davis.Sh ERRORS 508269e767SBrooks DavisThe 518269e767SBrooks Davis.Fn munmap 528269e767SBrooks Davissystem call 538269e767SBrooks Daviswill fail if: 548269e767SBrooks Davis.Bl -tag -width Er 558269e767SBrooks Davis.It Bq Er EINVAL 568269e767SBrooks DavisThe 578269e767SBrooks Davis.Fa len 58fab411c4SEd Masteargument was zero, or 598269e767SBrooks Davissome part of the region being unmapped is outside the 608269e767SBrooks Davisvalid address range for a process. 618269e767SBrooks Davis.El 628269e767SBrooks Davis.Sh "SEE ALSO" 638269e767SBrooks Davis.Xr madvise 2 , 648269e767SBrooks Davis.Xr mincore 2 , 658269e767SBrooks Davis.Xr mmap 2 , 668269e767SBrooks Davis.Xr mprotect 2 , 678269e767SBrooks Davis.Xr msync 2 , 688269e767SBrooks Davis.Xr getpagesize 3 69*724e383bSEd Maste.Sh STANDARDS 70*724e383bSEd MasteThe 71*724e383bSEd Maste.Fn munmap 72*724e383bSEd Mastesystem call conforms to 73*724e383bSEd Maste.St -p1003.1-2024 . 74*724e383bSEd MastePortable programs should ensure that 75*724e383bSEd Maste.Fa addr 76*724e383bSEd Masteis a multiple of the page size as returned by 77*724e383bSEd Maste.Xr sysconf 3 . 788269e767SBrooks Davis.Sh HISTORY 798269e767SBrooks DavisThe 808269e767SBrooks Davis.Fn munmap 818269e767SBrooks Davissystem call first appeared in 828269e767SBrooks Davis.Bx 4.4 . 83