xref: /freebsd-14.2/lib/libc/sys/munmap.2 (revision fbc400a6)
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32.\"	@(#)munmap.2	8.3 (Berkeley) 5/27/94
33.\"	$Id$
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35.Dd May 27, 1994
36.Dt MUNMAP 2
37.Os
38.Sh NAME
39.Nm munmap
40.Nd remove a mapping
41.Sh SYNOPSIS
42.Fd #include <sys/types.h>
43.Fd #include <sys/mman.h>
44.Ft int
45.Fn munmap "void *addr" "size_t len"
46.Sh DESCRIPTION
47The
48.Fn munmap
49system call
50deletes the mappings for the specified address range,
51and causes further references to addresses within the range
52to generate invalid memory references.
53.Sh RETURN VALUES
54Upon successful completion,
55.Fn munmap
56returns zero.
57Otherwise, a value of -1 is returned and
58.Va errno
59is set to indicate the error.
60.Sh ERRORS
61.Fn Munmap
62will fail if:
63.Bl -tag -width Er
64.It Bq Er EINVAL
65The
66.Fa addr
67parameter was not page aligned, the
68.Fa len
69parameter was negative, or
70some part of the region being unmapped is outside the
71valid address range for a process.
72.Sh "SEE ALSO"
73.Xr madvise 2 ,
74.Xr mincore 2 ,
75.Xr mprotect 2 ,
76.Xr msync 2 ,
77.Xr munmap 2 ,
78.Xr getpagesize 3
79.Sh HISTORY
80The
81.Fn munmap
82function first appeared in
83.Bx 4.4 .
84