See the current Perl documentation for IPC::SysV.
Here is our local, out-dated (pre-5.6) version:

IPC::SysV - SysV IPC constants

use IPC::SysV qw(IPC_STAT IPC_PRIVATE);

IPC::SysV defines and conditionally exports all the constants defined in your system include files which are needed by the SysV
IPC calls.
Graham Barr <gbarr@pobox.com> Jarkko Hietaniemi <jhi@iki.fi>
Copyright (c) 1997 Graham Barr. All rights reserved. This program is free software; you can redistribute it and/or modify it under the same terms as Perl itself.