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.\" @(#)munmap.2 8.3 (Berkeley) 5/27/94
.\" $FreeBSD$
.\"
.Dd June 22, 2017
.Dt MUNMAP 2
.Os
.Sh NAME
.Nm munmap
.Nd remove a mapping
.Sh LIBRARY
.Lb libc
.Sh SYNOPSIS
.In sys/mman.h
.Ft int
.Fn munmap "void *addr" "size_t len"
.Sh DESCRIPTION
The
.Fn munmap
system call
deletes the mappings and guards for the specified address range,
and causes further references to addresses within the range
to generate invalid memory references.
.Sh RETURN VALUES
.Rv -std munmap
.Sh ERRORS
The
.Fn munmap
system call
will fail if:
.Bl -tag -width Er
.It Bq Er EINVAL
The
.Fa addr
argument was not page aligned, the
.Fa len
argument was zero or negative, or
some part of the region being unmapped is outside the
valid address range for a process.
.El
.Sh "SEE ALSO"
.Xr madvise 2 ,
.Xr mincore 2 ,
.Xr mmap 2 ,
.Xr mprotect 2 ,
.Xr msync 2 ,
.Xr getpagesize 3
.Sh HISTORY
The
.Fn munmap
system call first appeared in
.Bx 4.4 .
