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MUNMAP(2) FreeBSD System Calls Manual MUNMAP(2)
NAME
munmap - remove a mapping
LIBRARY
Standard C Library (libc, -lc)
SYNOPSIS
#include <sys/mman.h>
int
munmap(void *addr, size_t len);
DESCRIPTION
The 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.
RETURN VALUES
The munmap() function returns the value 0 if successful; otherwise the
value -1 is returned and the global variable errno is set to indicate the
error.
ERRORS
The munmap() system call will fail if:
[EINVAL] The addr argument was not page aligned, the len
argument was zero or negative, or some part of the
region being unmapped is outside the valid address
range for a process.
SEE ALSO
madvise(2), mincore(2), mmap(2), mprotect(2), msync(2), getpagesize(3)
HISTORY
The munmap() system call first appeared in 4.4BSD.
FreeBSD 14.2-RELEASE June 22, 2017 FreeBSD 14.2-RELEASE