IPC::SysV(3perl)       Perl Programmers Reference Guide       IPC::SysV(3perl)


NAME
       IPC::SysV - System V IPC constants and system calls

SYNOPSIS
         use IPC::SysV qw(IPC_STAT IPC_PRIVATE);

DESCRIPTION
       "IPC::SysV" defines and conditionally exports all the constants defined
       in your system include files which are needed by the SysV IPC calls.
       Common ones include

         IPC_CREAT IPC_EXCL IPC_NOWAIT IPC_PRIVATE IPC_RMID IPC_SET IPC_STAT
         GETVAL SETVAL GETPID GETNCNT GETZCNT GETALL SETALL
         SEM_A SEM_R SEM_UNDO
         SHM_RDONLY SHM_RND SHMLBA

       and auxiliary ones

         S_IRUSR S_IWUSR S_IRWXU
         S_IRGRP S_IWGRP S_IRWXG
         S_IROTH S_IWOTH S_IRWXO

       but your system might have more.

       ftok( PATH )
       ftok( PATH, ID )
           Return a key based on PATH and ID, which can be used as a key for
           "msgget", "semget" and "shmget". See ftok(3).

           If ID is omitted, it defaults to 1. If a single character is given
           for ID, the numeric value of that character is used.

       shmat( ID, ADDR, FLAG )
           Attach the shared memory segment identified by ID to the address
           space of the calling process. See shmat(2).

           ADDR should be "undef" unless you really know what you're doing.

       shmdt( ADDR )
           Detach the shared memory segment located at the address specified
           by ADDR from the address space of the calling process. See
           shmdt(2).

       memread( ADDR, VAR, POS, SIZE )
           Reads SIZE bytes from a memory segment at ADDR starting at position
           POS.  VAR must be a variable that will hold the data read. Returns
           true if successful, or false if there is an error. memread() taints
           the variable.

       memwrite( ADDR, STRING, POS, SIZE )
           Writes SIZE bytes from STRING to a memory segment at ADDR starting
           at position POS. If STRING is too long, only SIZE bytes are used;
           if STRING is too short, nulls are written to fill out SIZE bytes.
           Returns true if successful, or false if there is an error.

SEE ALSO
       IPC::Msg, IPC::Semaphore, IPC::SharedMem, ftok(3), shmat(2), shmdt(2)

AUTHORS
       Graham Barr <gbarr@pobox.com>, Jarkko Hietaniemi <jhi@iki.fi>, Marcus
       Holland-Moritz <mhx@cpan.org>

COPYRIGHT
       Version 2.x, Copyright (C) 2007-2013, Marcus Holland-Moritz.

       Version 1.x, Copyright (c) 1997, Graham Barr.

       This program is free software; you can redistribute it and/or modify it
       under the same terms as Perl itself.

perl v5.40.0                      2024-09-01                  IPC::SysV(3perl)