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shmdt(2)
NAME
  shmdt - Detach a shared memory region

SYNOPSIS
  #include <sys/shm.h>

  int shmdt(
	  const void *addr );

  Application developers may want to specify an #include statement for
  <sys/types.h> and <sys/ipc.h> before the one for <sys/shm.h> if programs
  are being developed for multiple platforms.  The additional #include
  statements are not required on Tru64 UNIX systems or by ISO or XSH
  standards, but may be on other vendors' systems that conform to these
  standards.

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

  shmdt():  XSH4.0, XSH4.2, XSH5.0

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

PARAMETERS
  addr	  Specifies the starting virtual address for the shared memory region
	  to be detached. This is the address returned by a previous shmat()
	  call.

DESCRIPTION
  The shmdt() function detaches the shared memory region at the address
  specified by the addr parameter from the address space of the calling
  process. Other instances of the region attached at other addresses are
  unaffected.

NOTES
  The librt library contains alternative interfaces for interprocess
  communication. The names of these routines adhere to the format shm_* and
  their reference pages are listed in SEE ALSO.

RETURN VALUES
  Upon successful completion, the shmdt() function decrements the value of
  shm_nattach in the data structure associated with the shared memory ID of
  the attached shared memory segment and returns 0 (zero). Upon failure, the
  shared memory segment is not detached, -1 is returned, and errno is set to
  indicate the error.

ERRORS
  The shmdt() function sets errno to the specified values for the following
  conditions:

  [EINVAL]
	  The addr parameter does not specify the starting address of a
	  shared memory region.

SEE ALSO
  Functions: shmat(2), shmctl(2), shmget(2), shm_open(3), shm_unlink(3)

  Data structures: shmid_ds(4)

  Standards: standards(5)

Index for Section 2

Alphabetical listing for S

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