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 len argument was zero, 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)

STANDARDS

     The munmap() system call conforms to IEEE Std 1003.1-2024 ("POSIX.1").
     Portable programs should ensure that addr is a multiple of the page size
     as returned by sysconf(3).

HISTORY

     The munmap() system call first appeared in 4.4BSD.

FreeBSD 15.1-STABLE-HBSD       January 16, 2025                      MUNMAP(2)