Index for Section 2

Alphabetical listing for M

Bottom of page

munmap(2)
NAME
  munmap - Unmap a mapped region

SYNOPSIS
  #include <sys/mman.h>

  int munmap(
	  void *addr,
	  size_t len );

  [Tru64 UNIX]	The following definition of the munmap() function does not
  conform to current standards and is supported only for backward
  compatibility. See standards(5).

  #include <sys/mman.h>

  int munmap(
	  caddr_t addr,
	  size_t len );

STANDARDS
  Interfaces documented on this reference page conform to industry standards
  as follows:

  munmap(): XSH4.2, XSH5.0

  Refer to the standards(5) reference page for more information about
  industry standards and associated tags.

PARAMETERS
  addr
      Specifies the address of the region to be unmapped.

  len Specifies the length in bytes of the region to be unmapped.

DESCRIPTION
  The munmap() function unmaps a mapped file or shared memory region.

  The addr and len parameters specify the address and length in bytes,
  respectively, of the region to be unmapped. The len parameter must be a
  multiple of the page size as returned by sysconf(_SC_PAGE_SIZE). If len is
  not a multiple of the page size as returned by sysconf(_SC_PAGE_SIZE), the
  length of the region will be rounded up to the next multiple of the page
  size.

  The result of using an address which lies in an unmapped region and not in
  any subsequently mapped region is undefined.

RETURN VALUES
  Upon successful completion, the munmap() function returns 0 (zero).
  Otherwise, munmap() returns -1 and sets errno to indicate the error.

ERRORS
  If the munmap() function fails, errno is set as follows:

  [EINVAL]
      One of the following conditions applies:

	·  The addr parameter is not a multiple of the page size as returned
	   by sysconf(_SC_PAGE_SIZE).

	·  The len parameter is 0 (zero).

	·  Addresses in the range [addr, addr + len) are outside the valid
	   range for the address space of a process.

SEE ALSO
  Functions: mmap(2), sysconf(3)

  Standards: standards(5)

Index for Section 2

Alphabetical listing for M

Top of page